diff --git a/plugins/calendar/calendar.php b/plugins/calendar/calendar.php
index f8c5036c..fa2bc5ad 100644
--- a/plugins/calendar/calendar.php
+++ b/plugins/calendar/calendar.php
@@ -1,3311 +1,3311 @@
 <?php
 
 /**
  * Calendar plugin for Roundcube webmail
  *
  * @author Lazlo Westerhof <hello@lazlo.me>
  * @author Thomas Bruederli <bruederli@kolabsys.com>
  *
  * Copyright (C) 2010, Lazlo Westerhof <hello@lazlo.me>
  * Copyright (C) 2014-2015, Kolab Systems AG <contact@kolabsys.com>
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
  * published by the Free Software Foundation, either version 3 of the
  * License, or (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  * GNU Affero General Public License for more details.
  *
  * You should have received a copy of the GNU Affero General Public License
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 
 class calendar extends rcube_plugin
 {
   const FREEBUSY_UNKNOWN = 0;
   const FREEBUSY_FREE = 1;
   const FREEBUSY_BUSY = 2;
   const FREEBUSY_TENTATIVE = 3;
   const FREEBUSY_OOF = 4;
 
   const SESSION_KEY = 'calendar_temp';
 
   public $task = '?(?!logout).*';
   public $rc;
   public $lib;
   public $resources_dir;
   public $home;  // declare public to be used in other classes
   public $urlbase;
   public $timezone;
   public $timezone_offset;
   public $gmt_offset;
   public $ui;
 
   public $defaults = array(
     'calendar_default_view' => "agendaWeek",
     'calendar_timeslots'    => 2,
     'calendar_work_start'   => 6,
     'calendar_work_end'     => 18,
     'calendar_agenda_range' => 60,
     'calendar_agenda_sections' => 'smart',
     'calendar_event_coloring'  => 0,
     'calendar_time_indicator'  => true,
     'calendar_allow_invite_shared' => false,
     'calendar_itip_send_option'    => 3,
     'calendar_itip_after_action'   => 0,
   );
 
   private $ical;
   private $itip;
   private $driver;
 
 
   /**
    * Plugin initialization.
    */
   function init()
   {
     $this->require_plugin('libcalendaring');
 
     $this->rc = rcube::get_instance();
     $this->lib = libcalendaring::get_instance();
 
     $this->register_task('calendar', 'calendar');
 
     // load calendar configuration
     $this->load_config();
 
     // load localizations
     $this->add_texts('localization/', $this->rc->task == 'calendar' && (!$this->rc->action || $this->rc->action == 'print'));
 
     $this->timezone = $this->lib->timezone;
     $this->gmt_offset = $this->lib->gmt_offset;
     $this->dst_active = $this->lib->dst_active;
     $this->timezone_offset = $this->gmt_offset / 3600 - $this->dst_active;
 
     require($this->home . '/lib/calendar_ui.php');
     $this->ui = new calendar_ui($this);
 
     // catch iTIP confirmation requests that don're require a valid session
     if ($this->rc->action == 'attend' && !empty($_REQUEST['_t'])) {
       $this->add_hook('startup', array($this, 'itip_attend_response'));
     }
     else if ($this->rc->action == 'feed' && !empty($_REQUEST['_cal'])) {
       $this->add_hook('startup', array($this, 'ical_feed_export'));
     }
     else {
       // default startup routine
       $this->add_hook('startup', array($this, 'startup'));
     }
 
     $this->add_hook('user_delete', array($this, 'user_delete'));
   }
 
   /**
    * Startup hook
    */
   public function startup($args)
   {
     // the calendar module can be enabled/disabled by the kolab_auth plugin
     if ($this->rc->config->get('calendar_disabled', false) || !$this->rc->config->get('calendar_enabled', true))
         return;
 
     // load Calendar user interface
     if (!$this->rc->output->ajax_call && (!$this->rc->output->env['framed'] || $args['action'] == 'preview')) {
       $this->ui->init();
 
       // settings are required in (almost) every GUI step
       if ($args['action'] != 'attend')
         $this->rc->output->set_env('calendar_settings', $this->load_settings());
     }
 
     if ($args['task'] == 'calendar' && $args['action'] != 'save-pref') {
       if ($args['action'] != 'upload') {
         $this->load_driver();
       }
 
       // register calendar actions
       $this->register_action('index', array($this, 'calendar_view'));
       $this->register_action('event', array($this, 'event_action'));
       $this->register_action('calendar', array($this, 'calendar_action'));
       $this->register_action('count', array($this, 'count_events'));
       $this->register_action('load_events', array($this, 'load_events'));
       $this->register_action('export_events', array($this, 'export_events'));
       $this->register_action('import_events', array($this, 'import_events'));
       $this->register_action('upload', array($this, 'attachment_upload'));
       $this->register_action('get-attachment', array($this, 'attachment_get'));
       $this->register_action('freebusy-status', array($this, 'freebusy_status'));
       $this->register_action('freebusy-times', array($this, 'freebusy_times'));
       $this->register_action('randomdata', array($this, 'generate_randomdata'));
       $this->register_action('print', array($this,'print_view'));
       $this->register_action('mailimportitip', array($this, 'mail_import_itip'));
       $this->register_action('mailimportattach', array($this, 'mail_import_attachment'));
       $this->register_action('mailtoevent', array($this, 'mail_message2event'));
       $this->register_action('inlineui', array($this, 'get_inline_ui'));
       $this->register_action('check-recent', array($this, 'check_recent'));
       $this->register_action('itip-status', array($this, 'event_itip_status'));
       $this->register_action('itip-remove', array($this, 'event_itip_remove'));
       $this->register_action('itip-decline-reply', array($this, 'mail_itip_decline_reply'));
       $this->register_action('itip-delegate', array($this, 'mail_itip_delegate'));
       $this->register_action('resources-list', array($this, 'resources_list'));
       $this->register_action('resources-owner', array($this, 'resources_owner'));
       $this->register_action('resources-calendar', array($this, 'resources_calendar'));
       $this->register_action('resources-autocomplete', array($this, 'resources_autocomplete'));
       $this->add_hook('refresh', array($this, 'refresh'));
 
       // remove undo information...
       if ($undo = $_SESSION['calendar_event_undo']) {
         // ...after timeout
         $undo_time = $this->rc->config->get('undo_timeout', 0);
         if ($undo['ts'] < time() - $undo_time) {
           $this->rc->session->remove('calendar_event_undo');
           // @TODO: do EXPUNGE on kolab objects?
         }
       }
     }
     else if ($args['task'] == 'settings') {
       // add hooks for Calendar settings
       $this->add_hook('preferences_sections_list', array($this, 'preferences_sections_list'));
       $this->add_hook('preferences_list', array($this, 'preferences_list'));
       $this->add_hook('preferences_save', array($this, 'preferences_save')); 
     }
     else if ($args['task'] == 'mail') {
       // hooks to catch event invitations on incoming mails
       if ($args['action'] == 'show' || $args['action'] == 'preview') {
         $this->add_hook('template_object_messagebody', array($this, 'mail_messagebody_html'));
       }
 
       // add 'Create event' item to message menu
       if ($this->api->output->type == 'html') {
         $this->api->add_content(html::tag('li', null, 
           $this->api->output->button(array(
             'command'  => 'calendar-create-from-mail',
             'label'    => 'calendar.createfrommail',
             'type'     => 'link',
             'classact' => 'icon calendarlink active',
             'class'    => 'icon calendarlink',
             'innerclass' => 'icon calendar',
           ))),
           'messagemenu');
 
         $this->api->output->add_label('calendar.createfrommail');
       }
 
       $this->add_hook('messages_list', array($this, 'mail_messages_list'));
       $this->add_hook('message_compose', array($this, 'mail_message_compose'));
     }
     else if ($args['task'] == 'addressbook') {
       if ($this->rc->config->get('calendar_contact_birthdays')) {
         $this->add_hook('contact_update', array($this, 'contact_update'));
         $this->add_hook('contact_create', array($this, 'contact_update'));
       }
     }
 
     // add hooks to display alarms
     $this->add_hook('pending_alarms', array($this, 'pending_alarms'));
     $this->add_hook('dismiss_alarms', array($this, 'dismiss_alarms'));
   }
 
   /**
    * Helper method to load the backend driver according to local config
    */
   private function load_driver()
   {
     if (is_object($this->driver))
       return;
 
     $driver_name = $this->rc->config->get('calendar_driver', 'database');
     $driver_class = $driver_name . '_driver';
 
     require_once($this->home . '/drivers/calendar_driver.php');
     require_once($this->home . '/drivers/' . $driver_name . '/' . $driver_class . '.php');
 
     $this->driver = new $driver_class($this);
 
     if ($this->driver->undelete)
       $this->driver->undelete = $this->rc->config->get('undo_timeout', 0) > 0;
   }
 
   /**
    * Load iTIP functions
    */
   private function load_itip()
   {
     if (!$this->itip) {
       require_once($this->home . '/lib/calendar_itip.php');
       $this->itip = new calendar_itip($this);
       
       if ($this->rc->config->get('kolab_invitation_calendars'))
         $this->itip->set_rsvp_actions(array('accepted','tentative','declined','delegated','needs-action'));
     }
 
     return $this->itip;
   }
 
   /**
    * Load iCalendar functions
    */
   public function get_ical()
   {
     if (!$this->ical) {
       $this->ical = libcalendaring::get_ical();
     }
     
     return $this->ical;
   }
 
   /**
    * Get properties of the calendar this user has specified as default
    */
   public function get_default_calendar($sensitivity = null)
   {
     $default_id = $this->rc->config->get('calendar_default_calendar');
     $calendars = $this->driver->list_calendars(calendar_driver::FILTER_PERSONAL | calendar_driver::FILTER_WRITEABLE);
     $calendar = $calendars[$default_id] ?: null;
     if (!$calendar || $sensitivity) {
       foreach ($calendars as $cal) {
         if ($sensitivity && $cal['subtype'] == $sensitivity) {
           $calendar = $cal;
           break;
         }
         if ($cal['default'] && $cal['editable']) {
           $calendar = $cal;
         }
         if ($cal['editable']) {
           $first = $cal;
         }
       }
     }
 
     return $calendar ?: $first;
   }
 
 
   /**
    * Render the main calendar view from skin template
    */
   function calendar_view()
   {
     $this->rc->output->set_pagetitle($this->gettext('calendar'));
 
     // Add CSS stylesheets to the page header
     $this->ui->addCSS();
 
     // Add JS files to the page header
     $this->ui->addJS();
 
     $this->ui->init_templates();
     $this->rc->output->add_label('lowest','low','normal','high','highest','delete','cancel','uploading','noemailwarning','close');
     $this->rc->output->add_label('libcalendaring.itipaccepted','libcalendaring.itiptentative','libcalendaring.itipdeclined','libcalendaring.itipdelegated','libcalendaring.expandattendeegroup','libcalendaring.expandattendeegroupnodata');
 
     // initialize attendees autocompletion
-    rcube_autocomplete_init();
+    $this->rc->autocomplete_init();
 
     $this->rc->output->set_env('timezone', $this->timezone->getName());
     $this->rc->output->set_env('calendar_driver', $this->rc->config->get('calendar_driver'), false);
     $this->rc->output->set_env('calendar_resources', (bool)$this->rc->config->get('calendar_resources_driver'));
     $this->rc->output->set_env('mscolors', jqueryui::get_color_values());
     $this->rc->output->set_env('identities-selector', $this->ui->identity_select(array('id' => 'edit-identities-list', 'aria-label' => $this->gettext('roleorganizer'))));
 
     $view = rcube_utils::get_input_value('view', rcube_utils::INPUT_GPC);
     if (in_array($view, array('agendaWeek', 'agendaDay', 'month', 'table')))
       $this->rc->output->set_env('view', $view);
 
     if ($date = rcube_utils::get_input_value('date', rcube_utils::INPUT_GPC))
       $this->rc->output->set_env('date', $date);
 
     if ($msgref = rcube_utils::get_input_value('itip', rcube_utils::INPUT_GPC))
       $this->rc->output->set_env('itip_events', $this->itip_events($msgref));
 
     $this->rc->output->send("calendar.calendar");
   }
 
   /**
    * Handler for preferences_sections_list hook.
    * Adds Calendar settings sections into preferences sections list.
    *
    * @param array Original parameters
    * @return array Modified parameters
    */
   function preferences_sections_list($p)
   {
     $p['list']['calendar'] = array(
       'id' => 'calendar', 'section' => $this->gettext('calendar'),
     );
 
     return $p;
   }
 
   /**
    * Handler for preferences_list hook.
    * Adds options blocks into Calendar settings sections in Preferences.
    *
    * @param array Original parameters
    * @return array Modified parameters
    */
   function preferences_list($p)
   {
     if ($p['section'] != 'calendar') {
       return $p;
     }
 
     $no_override = array_flip((array)$this->rc->config->get('dont_override'));
 
     $p['blocks']['view']['name'] = $this->gettext('mainoptions');
 
     if (!isset($no_override['calendar_default_view'])) {
       if (!$p['current']) {
         $p['blocks']['view']['content'] = true;
         return $p;
       }
 
       $field_id = 'rcmfd_default_view';
       $select = new html_select(array('name' => '_default_view', 'id' => $field_id));
       $select->add($this->gettext('day'), "agendaDay");
       $select->add($this->gettext('week'), "agendaWeek");
       $select->add($this->gettext('month'), "month");
       $select->add($this->gettext('agenda'), "table");
       $p['blocks']['view']['options']['default_view'] = array(
         'title' => html::label($field_id, rcube::Q($this->gettext('default_view'))),
         'content' => $select->show($this->rc->config->get('calendar_default_view', $this->defaults['calendar_default_view'])),
       );
     }
 
     if (!isset($no_override['calendar_timeslots'])) {
       if (!$p['current']) {
         $p['blocks']['view']['content'] = true;
         return $p;
       }
 
       $field_id = 'rcmfd_timeslot';
       $choices = array('1', '2', '3', '4', '6');
       $select = new html_select(array('name' => '_timeslots', 'id' => $field_id));
       $select->add($choices);
       $p['blocks']['view']['options']['timeslots'] = array(
         'title' => html::label($field_id, rcube::Q($this->gettext('timeslots'))),
         'content' => $select->show(strval($this->rc->config->get('calendar_timeslots', $this->defaults['calendar_timeslots']))),
       );
     }
 
     if (!isset($no_override['calendar_first_day'])) {
       if (!$p['current']) {
         $p['blocks']['view']['content'] = true;
         return $p;
       }
 
       $field_id = 'rcmfd_firstday';
       $select = new html_select(array('name' => '_first_day', 'id' => $field_id));
-      $select->add(rcube_label('sunday'), '0');
-      $select->add(rcube_label('monday'), '1');
-      $select->add(rcube_label('tuesday'), '2');
-      $select->add(rcube_label('wednesday'), '3');
-      $select->add(rcube_label('thursday'), '4');
-      $select->add(rcube_label('friday'), '5');
-      $select->add(rcube_label('saturday'), '6');
+      $select->add($this->gettext('sunday'), '0');
+      $select->add($this->gettext('monday'), '1');
+      $select->add($this->gettext('tuesday'), '2');
+      $select->add($this->gettext('wednesday'), '3');
+      $select->add($this->gettext('thursday'), '4');
+      $select->add($this->gettext('friday'), '5');
+      $select->add($this->gettext('saturday'), '6');
       $p['blocks']['view']['options']['first_day'] = array(
         'title' => html::label($field_id, rcube::Q($this->gettext('first_day'))),
         'content' => $select->show(strval($this->rc->config->get('calendar_first_day', $this->defaults['calendar_first_day']))),
       );
     }
 
     if (!isset($no_override['calendar_first_hour'])) {
       if (!$p['current']) {
         $p['blocks']['view']['content'] = true;
         return $p;
       }
 
       $time_format = $this->rc->config->get('time_format', libcalendaring::to_php_date_format($this->rc->config->get('calendar_time_format', $this->defaults['calendar_time_format'])));
       $select_hours = new html_select();
       for ($h = 0; $h < 24; $h++)
         $select_hours->add(date($time_format, mktime($h, 0, 0)), $h);
 
       $field_id = 'rcmfd_firsthour';
       $p['blocks']['view']['options']['first_hour'] = array(
         'title' => html::label($field_id, rcube::Q($this->gettext('first_hour'))),
         'content' => $select_hours->show($this->rc->config->get('calendar_first_hour', $this->defaults['calendar_first_hour']), array('name' => '_first_hour', 'id' => $field_id)),
       );
     }
 
     if (!isset($no_override['calendar_work_start'])) {
       if (!$p['current']) {
         $p['blocks']['view']['content'] = true;
         return $p;
       }
 
       $field_id = 'rcmfd_workstart';
       $p['blocks']['view']['options']['workinghours'] = array(
         'title' => html::label($field_id, rcube::Q($this->gettext('workinghours'))),
         'content' => $select_hours->show($this->rc->config->get('calendar_work_start', $this->defaults['calendar_work_start']), array('name' => '_work_start', 'id' => $field_id)) .
         ' &mdash; ' . $select_hours->show($this->rc->config->get('calendar_work_end', $this->defaults['calendar_work_end']), array('name' => '_work_end', 'id' => $field_id)),
       );
     }
 
     if (!isset($no_override['calendar_event_coloring'])) {
       if (!$p['current']) {
         $p['blocks']['view']['content'] = true;
         return $p;
       }
 
       $field_id = 'rcmfd_coloring';
       $select_colors = new html_select(array('name' => '_event_coloring', 'id' => $field_id));
       $select_colors->add($this->gettext('coloringmode0'), 0);
       $select_colors->add($this->gettext('coloringmode1'), 1);
       $select_colors->add($this->gettext('coloringmode2'), 2);
       $select_colors->add($this->gettext('coloringmode3'), 3);
 
       $p['blocks']['view']['options']['eventcolors'] = array(
         'title' => html::label($field_id . 'value', rcube::Q($this->gettext('eventcoloring'))),
         'content' => $select_colors->show($this->rc->config->get('calendar_event_coloring', $this->defaults['calendar_event_coloring'])),
       );
     }
 
     // loading driver is expensive, don't do it if not needed
     $this->load_driver();
 
     if (!isset($no_override['calendar_default_alarm_type'])) {
       if (!$p['current']) {
         $p['blocks']['view']['content'] = true;
         return $p;
       }
 
       $field_id = 'rcmfd_alarm';
       $select_type = new html_select(array('name' => '_alarm_type', 'id' => $field_id));
       $select_type->add($this->gettext('none'), '');
       foreach ($this->driver->alarm_types as $type)
-        $select_type->add(rcube_label(strtolower("alarm{$type}option"), 'libcalendaring'), $type);
+        $select_type->add($this->gettext(strtolower("alarm{$type}option"), 'libcalendaring'), $type);
 
       $p['blocks']['view']['options']['alarmtype'] = array(
         'title' => html::label($field_id, rcube::Q($this->gettext('defaultalarmtype'))),
         'content' => $select_type->show($this->rc->config->get('calendar_default_alarm_type', '')),
       );
     }
 
     if (!isset($no_override['calendar_default_alarm_offset'])) {
       if (!$p['current']) {
         $p['blocks']['view']['content'] = true;
         return $p;
       }
 
       $field_id = 'rcmfd_alarm';
       $input_value = new html_inputfield(array('name' => '_alarm_value', 'id' => $field_id . 'value', 'size' => 3));
       $select_offset = new html_select(array('name' => '_alarm_offset', 'id' => $field_id . 'offset'));
       foreach (array('-M','-H','-D','+M','+H','+D') as $trigger)
-        $select_offset->add(rcube_label('trigger' . $trigger, 'libcalendaring'), $trigger);
+        $select_offset->add($this->gettext('trigger' . $trigger, 'libcalendaring'), $trigger);
 
       $preset = libcalendaring::parse_alarm_value($this->rc->config->get('calendar_default_alarm_offset', '-15M'));
       $p['blocks']['view']['options']['alarmoffset'] = array(
         'title' => html::label($field_id . 'value', rcube::Q($this->gettext('defaultalarmoffset'))),
         'content' => $input_value->show($preset[0]) . ' ' . $select_offset->show($preset[1]),
       );
     }
 
     if (!isset($no_override['calendar_default_calendar'])) {
       if (!$p['current']) {
         $p['blocks']['view']['content'] = true;
         return $p;
       }
       // default calendar selection
       $field_id = 'rcmfd_default_calendar';
       $select_cal = new html_select(array('name' => '_default_calendar', 'id' => $field_id, 'is_escaped' => true));
       foreach ((array)$this->driver->list_calendars(calendar_driver::FILTER_PERSONAL) as $id => $prop) {
         $select_cal->add($prop['name'], strval($id));
         if ($prop['default'])
           $default_calendar = $id;
       }
       $p['blocks']['view']['options']['defaultcalendar'] = array(
         'title' => html::label($field_id . 'value', rcube::Q($this->gettext('defaultcalendar'))),
         'content' => $select_cal->show($this->rc->config->get('calendar_default_calendar', $default_calendar)),
       );
     }
 
     $p['blocks']['itip']['name'] = $this->gettext('itipoptions');
 
     // Invitations handling
     if (!isset($no_override['calendar_itip_after_action'])) {
       if (!$p['current']) {
         $p['blocks']['itip']['content'] = true;
         return $p;
       }
 
       $field_id = 'rcmfd_after_action';
       $select   = new html_select(array('name' => '_after_action', 'id' => $field_id,
         'onchange' => "\$('#{$field_id}_select')[this.value == 4 ? 'show' : 'hide']()"));
 
       $select->add($this->gettext('afternothing'), '');
       $select->add($this->gettext('aftertrash'), 1);
       $select->add($this->gettext('afterdelete'), 2);
       $select->add($this->gettext('afterflagdeleted'), 3);
       $select->add($this->gettext('aftermoveto'), 4);
 
       $val = $this->rc->config->get('calendar_itip_after_action', $this->defaults['calendar_itip_after_action']);
       if ($val !== null && $val !== '' && !is_int($val)) {
         $folder = $val;
         $val    = 4;
       }
 
       $folders = $this->rc->folder_selector(array(
           'id'            => $field_id . '_select',
           'name'          => '_after_action_folder',
           'maxlength'     => 30,
           'folder_filter' => 'mail',
           'folder_rights' => 'w',
           'style'         => $val !== 4 ? 'display:none' : '',
       ));
 
       $p['blocks']['itip']['options']['after_action'] = array(
         'title'   => html::label($field_id, rcube::Q($this->gettext('afteraction'))),
         'content' => $select->show($val) . $folders->show($folder),
       );
     }
 
     // category definitions
     if (!$this->driver->nocategories && !isset($no_override['calendar_categories'])) {
         $p['blocks']['categories']['name'] = $this->gettext('categories');
 
         if (!$p['current']) {
           $p['blocks']['categories']['content'] = true;
           return $p;
         }
 
         $categories = (array) $this->driver->list_categories();
         $categories_list = '';
         foreach ($categories as $name => $color) {
           $key = md5($name);
           $field_class = 'rcmfd_category_' . str_replace(' ', '_', $name);
           $category_remove = new html_inputfield(array('type' => 'button', 'value' => 'X', 'class' => 'button', 'onclick' => '$(this).parent().remove()', 'title' => $this->gettext('remove_category')));
           $category_name  = new html_inputfield(array('name' => "_categories[$key]", 'class' => $field_class, 'size' => 30, 'disabled' => $this->driver->categoriesimmutable));
           $category_color = new html_inputfield(array('name' => "_colors[$key]", 'class' => "$field_class colors", 'size' => 6));
           $hidden = $this->driver->categoriesimmutable ? html::tag('input', array('type' => 'hidden', 'name' => "_categories[$key]", 'value' => $name)) : '';
           $categories_list .= html::div(null, $hidden . $category_name->show($name) . '&nbsp;' . $category_color->show($color) . '&nbsp;' . $category_remove->show());
         }
 
         $p['blocks']['categories']['options']['category_' . $name] = array(
           'content' => html::div(array('id' => 'calendarcategories'), $categories_list),
         );
 
         $field_id = 'rcmfd_new_category';
         $new_category = new html_inputfield(array('name' => '_new_category', 'id' => $field_id, 'size' => 30));
         $add_category = new html_inputfield(array('type' => 'button', 'class' => 'button', 'value' => $this->gettext('add_category'),  'onclick' => "rcube_calendar_add_category()"));
         $p['blocks']['categories']['options']['categories'] = array(
           'content' => $new_category->show('') . '&nbsp;' . $add_category->show(),
         );
 
         $this->rc->output->add_script('function rcube_calendar_add_category(){
           var name = $("#rcmfd_new_category").val();
           if (name.length) {
             var input = $("<input>").attr("type", "text").attr("name", "_categories[]").attr("size", 30).val(name);
             var color = $("<input>").attr("type", "text").attr("name", "_colors[]").attr("size", 6).addClass("colors").val("000000");
             var button = $("<input>").attr("type", "button").attr("value", "X").addClass("button").click(function(){ $(this).parent().remove() });
             $("<div>").append(input).append("&nbsp;").append(color).append("&nbsp;").append(button).appendTo("#calendarcategories");
             color.miniColors({ colorValues:(rcmail.env.mscolors || []) });
             $("#rcmfd_new_category").val("");
           }
         }');
 
         $this->rc->output->add_script('$("#rcmfd_new_category").keypress(function(event){
           if (event.which == 13) {
             rcube_calendar_add_category();
             event.preventDefault();
           }
         });
         ', 'docready');
 
         // load miniColors js/css files
         jqueryui::miniColors();
     }
 
     // virtual birthdays calendar
     if (!isset($no_override['calendar_contact_birthdays'])) {
       $p['blocks']['birthdays']['name'] = $this->gettext('birthdayscalendar');
 
       if (!$p['current']) {
         $p['blocks']['birthdays']['content'] = true;
         return $p;
       }
 
       $field_id = 'rcmfd_contact_birthdays';
       $input    = new html_checkbox(array('name' => '_contact_birthdays', 'id' => $field_id, 'value' => 1, 'onclick' => '$(".calendar_birthday_props").prop("disabled",!this.checked)'));
 
       $p['blocks']['birthdays']['options']['contact_birthdays'] = array(
         'title'   => html::label($field_id, $this->gettext('displaybirthdayscalendar')),
         'content' => $input->show($this->rc->config->get('calendar_contact_birthdays')?1:0),
       );
 
       $input_attrib = array(
         'class' => 'calendar_birthday_props',
         'disabled' => !$this->rc->config->get('calendar_contact_birthdays'),
       );
 
       $sources = array();
       $checkbox = new html_checkbox(array('name' => '_birthday_adressbooks[]') + $input_attrib);
       foreach ($this->rc->get_address_sources(false, true) as $source) {
         $active = in_array($source['id'], (array)$this->rc->config->get('calendar_birthday_adressbooks', array())) ? $source['id'] : '';
         $sources[] = html::label(null, $checkbox->show($active, array('value' => $source['id'])) . '&nbsp;' . rcube::Q($source['realname'] ?: $source['name']));
       }
 
       $p['blocks']['birthdays']['options']['birthday_adressbooks'] = array(
         'title'   => rcube::Q($this->gettext('birthdayscalendarsources')),
         'content' => join(html::br(), $sources),
       );
 
       $field_id = 'rcmfd_birthdays_alarm';
       $select_type = new html_select(array('name' => '_birthdays_alarm_type', 'id' => $field_id) + $input_attrib);
       $select_type->add($this->gettext('none'), '');
       foreach ($this->driver->alarm_types as $type) {
-        $select_type->add(rcube_label(strtolower("alarm{$type}option"), 'libcalendaring'), $type);
+        $select_type->add($this->gettext(strtolower("alarm{$type}option"), 'libcalendaring'), $type);
       }
 
       $input_value = new html_inputfield(array('name' => '_birthdays_alarm_value', 'id' => $field_id . 'value', 'size' => 3) + $input_attrib);
       $select_offset = new html_select(array('name' => '_birthdays_alarm_offset', 'id' => $field_id . 'offset') + $input_attrib);
       foreach (array('-M','-H','-D') as $trigger)
-        $select_offset->add(rcube_label('trigger' . $trigger, 'libcalendaring'), $trigger);
+        $select_offset->add($this->gettext('trigger' . $trigger, 'libcalendaring'), $trigger);
 
       $preset = libcalendaring::parse_alarm_value($this->rc->config->get('calendar_birthdays_alarm_offset', '-1D'));
       $p['blocks']['birthdays']['options']['birthdays_alarmoffset'] = array(
         'title' => html::label($field_id . 'value', rcube::Q($this->gettext('showalarms'))),
         'content' => $select_type->show($this->rc->config->get('calendar_birthdays_alarm_type', '')) . ' ' . $input_value->show($preset[0]) . '&nbsp;' . $select_offset->show($preset[1]),
       );
     }
 
     return $p;
   }
 
   /**
    * Handler for preferences_save hook.
    * Executed on Calendar settings form submit.
    *
    * @param array Original parameters
    * @return array Modified parameters
    */
   function preferences_save($p)
   {
     if ($p['section'] == 'calendar') {
       $this->load_driver();
 
       // compose default alarm preset value
       $alarm_offset  = rcube_utils::get_input_value('_alarm_offset', rcube_utils::INPUT_POST);
       $alarm_value   = rcube_utils::get_input_value('_alarm_value', rcube_utils::INPUT_POST);
       $default_alarm = $alarm_offset[0] . intval($alarm_value) . $alarm_offset[1];
 
       $birthdays_alarm_offset = rcube_utils::get_input_value('_birthdays_alarm_offset', rcube_utils::INPUT_POST);
       $birthdays_alarm_value  = rcube_utils::get_input_value('_birthdays_alarm_value', rcube_utils::INPUT_POST);
       $birthdays_alarm_value  = $birthdays_alarm_offset[0] . intval($birthdays_alarm_value) . $birthdays_alarm_offset[1];
 
       $p['prefs'] = array(
         'calendar_default_view' => rcube_utils::get_input_value('_default_view', rcube_utils::INPUT_POST),
         'calendar_timeslots'    => intval(rcube_utils::get_input_value('_timeslots', rcube_utils::INPUT_POST)),
         'calendar_first_day'    => intval(rcube_utils::get_input_value('_first_day', rcube_utils::INPUT_POST)),
         'calendar_first_hour'   => intval(rcube_utils::get_input_value('_first_hour', rcube_utils::INPUT_POST)),
         'calendar_work_start'   => intval(rcube_utils::get_input_value('_work_start', rcube_utils::INPUT_POST)),
         'calendar_work_end'     => intval(rcube_utils::get_input_value('_work_end', rcube_utils::INPUT_POST)),
         'calendar_event_coloring'       => intval(rcube_utils::get_input_value('_event_coloring', rcube_utils::INPUT_POST)),
         'calendar_default_alarm_type'   => rcube_utils::get_input_value('_alarm_type', rcube_utils::INPUT_POST),
         'calendar_default_alarm_offset' => $default_alarm,
         'calendar_default_calendar'     => rcube_utils::get_input_value('_default_calendar', rcube_utils::INPUT_POST),
         'calendar_date_format' => null,  // clear previously saved values
         'calendar_time_format' => null,
         'calendar_contact_birthdays'    => rcube_utils::get_input_value('_contact_birthdays', rcube_utils::INPUT_POST) ? true : false,
         'calendar_birthday_adressbooks' => (array) rcube_utils::get_input_value('_birthday_adressbooks', rcube_utils::INPUT_POST),
         'calendar_birthdays_alarm_type'   => rcube_utils::get_input_value('_birthdays_alarm_type', rcube_utils::INPUT_POST),
         'calendar_birthdays_alarm_offset' => $birthdays_alarm_value ?: null,
         'calendar_itip_after_action'      => intval(rcube_utils::get_input_value('_after_action', rcube_utils::INPUT_POST)),
       );
 
       if ($p['prefs']['calendar_itip_after_action'] == 4) {
         $p['prefs']['calendar_itip_after_action'] = rcube_utils::get_input_value('_after_action_folder', rcube_utils::INPUT_POST, true);
       }
 
       // categories
       if (!$this->driver->nocategories) {
         $old_categories = $new_categories = array();
         foreach ($this->driver->list_categories() as $name => $color) {
           $old_categories[md5($name)] = $name;
         }
 
         $categories = (array) rcube_utils::get_input_value('_categories', rcube_utils::INPUT_POST);
         $colors     = (array) rcube_utils::get_input_value('_colors', rcube_utils::INPUT_POST);
 
         foreach ($categories as $key => $name) {
           $color = preg_replace('/^#/', '', strval($colors[$key]));
 
           // rename categories in existing events -> driver's job
           if ($oldname = $old_categories[$key]) {
             $this->driver->replace_category($oldname, $name, $color);
             unset($old_categories[$key]);
           }
           else
             $this->driver->add_category($name, $color);
 
           $new_categories[$name] = $color;
         }
 
         // these old categories have been removed, alter events accordingly -> driver's job
         foreach ((array)$old_categories[$key] as $key => $name) {
           $this->driver->remove_category($name);
         }
 
         $p['prefs']['calendar_categories'] = $new_categories;
       }
     }
 
     return $p;
   }
 
   /**
    * Dispatcher for calendar actions initiated by the client
    */
   function calendar_action()
   {
     $action = rcube_utils::get_input_value('action', rcube_utils::INPUT_GPC);
     $cal    = rcube_utils::get_input_value('c', rcube_utils::INPUT_GPC);
     $success = $reload = false;
 
     if (isset($cal['showalarms']))
       $cal['showalarms'] = intval($cal['showalarms']);
 
     switch ($action) {
       case "form-new":
       case "form-edit":
         echo $this->ui->calendar_editform($action, $cal);
         exit;
       case "new":
         $success = $this->driver->create_calendar($cal);
         $reload = true;
         break;
       case "edit":
         $success = $this->driver->edit_calendar($cal);
         $reload = true;
         break;
       case "delete":
         if ($success = $this->driver->delete_calendar($cal))
           $this->rc->output->command('plugin.destroy_source', array('id' => $cal['id']));
         break;
       case "subscribe":
         if (!$this->driver->subscribe_calendar($cal))
           $this->rc->output->show_message($this->gettext('errorsaving'), 'error');
         return;
       case "search":
         $results    = array();
         $color_mode = $this->rc->config->get('calendar_event_coloring', $this->defaults['calendar_event_coloring']);
         $query      = rcube_utils::get_input_value('q', rcube_utils::INPUT_GPC);
         $source     = rcube_utils::get_input_value('source', rcube_utils::INPUT_GPC);
 
         foreach ((array) $this->driver->search_calendars($query, $source) as $id => $prop) {
           $editname = $prop['editname'];
           unset($prop['editname']);  // force full name to be displayed
           $prop['active'] = false;
 
           // let the UI generate HTML and CSS representation for this calendar
           $html = $this->ui->calendar_list_item($id, $prop, $jsenv);
           $cal = $jsenv[$id];
           $cal['editname'] = $editname;
           $cal['html'] = $html;
           if (!empty($prop['color']))
             $cal['css'] = $this->ui->calendar_css_classes($id, $prop, $color_mode);
 
           $results[] = $cal;
         }
         // report more results available
         if ($this->driver->search_more_results)
           $this->rc->output->show_message('autocompletemore', 'info');
 
         $this->rc->output->command('multi_thread_http_response', $results, rcube_utils::get_input_value('_reqid', rcube_utils::INPUT_GPC));
         return;
     }
     
     if ($success)
       $this->rc->output->show_message('successfullysaved', 'confirmation');
     else {
       $error_msg = $this->gettext('errorsaving') . ($this->driver->last_error ? ': ' . $this->driver->last_error :'');
       $this->rc->output->show_message($error_msg, 'error');
     }
 
     $this->rc->output->command('plugin.unlock_saving');
 
     if ($success && $reload)
       $this->rc->output->command('plugin.reload_view');
   }
   
   
   /**
    * Dispatcher for event actions initiated by the client
    */
   function event_action()
   {
     $action = rcube_utils::get_input_value('action', rcube_utils::INPUT_GPC);
     $event  = rcube_utils::get_input_value('e', rcube_utils::INPUT_POST, true);
     $success = $reload = $got_msg = false;
     
     // force notify if hidden + active
     if ((int)$this->rc->config->get('calendar_itip_send_option', $this->defaults['calendar_itip_send_option']) === 1)
       $event['_notify'] = 1;
 
     // read old event data in order to find changes
     if (($event['_notify'] || $event['_decline']) && $action != 'new') {
       $old = $this->driver->get_event($event);
 
       // load main event if savemode is 'all' or if deleting 'future' events
       if (($event['_savemode'] == 'all' || ($event['_savemode'] == 'future' && $action == 'remove' && !$event['_decline'])) && $old['recurrence_id']) {
         $old['id'] = $old['recurrence_id'];
         $old = $this->driver->get_event($old);
       }
     }
 
     switch ($action) {
       case "new":
         // create UID for new event
         $event['uid'] = $this->generate_uid();
         $this->write_preprocess($event, $action);
         if ($success = $this->driver->new_event($event)) {
           $event['id'] = $event['uid'];
           $event['_savemode'] = 'all';
           $this->cleanup_event($event);
           $this->event_save_success($event, null, $action, true);
         }
         $reload = $success && $event['recurrence'] ? 2 : 1;
         break;
         
       case "edit":
         $this->write_preprocess($event, $action);
         if ($success = $this->driver->edit_event($event)) {
           $this->cleanup_event($event);
           $this->event_save_success($event, $old, $action, $success);
         }
         $reload = $success && ($event['recurrence'] || $event['_savemode'] || $event['_fromcalendar']) ? 2 : 1;
         break;
       
       case "resize":
         $this->write_preprocess($event, $action);
         if ($success = $this->driver->resize_event($event)) {
           $this->event_save_success($event, $old, $action, $success);
         }
         $reload = $event['_savemode'] ? 2 : 1;
         break;
       
       case "move":
         $this->write_preprocess($event, $action);
         if ($success = $this->driver->move_event($event)) {
           $this->event_save_success($event, $old, $action, $success);
         }
         $reload  = $success && $event['_savemode'] ? 2 : 1;
         break;
       
       case "remove":
         // remove previous deletes
         $undo_time = $this->driver->undelete ? $this->rc->config->get('undo_timeout', 0) : 0;
         $this->rc->session->remove('calendar_event_undo');
         
         // search for event if only UID is given
         if (!isset($event['calendar']) && $event['uid']) {
           if (!($event = $this->driver->get_event($event, calendar_driver::FILTER_WRITEABLE))) {
             break;
           }
           $undo_time = 0;
         }
 
         $success = $this->driver->remove_event($event, $undo_time < 1);
         $reload = (!$success || $event['_savemode']) ? 2 : 1;
 
         if ($undo_time > 0 && $success) {
           $_SESSION['calendar_event_undo'] = array('ts' => time(), 'data' => $event);
           // display message with Undo link.
           $msg = html::span(null, $this->gettext('successremoval'))
             . ' ' . html::a(array('onclick' => sprintf("%s.http_request('event', 'action=undo', %s.display_message('', 'loading'))",
               rcmail_output::JS_OBJECT_NAME, rcmail_output::JS_OBJECT_NAME)), $this->gettext('undo'));
           $this->rc->output->show_message($msg, 'confirmation', null, true, $undo_time);
           $got_msg = true;
         }
         else if ($success) {
           $this->rc->output->show_message('calendar.successremoval', 'confirmation');
           $got_msg = true;
         }
 
         // send cancellation for the main event
         if ($event['_savemode'] == 'all') {
           unset($old['_instance'], $old['recurrence_date'], $old['recurrence_id']);
         }
         // send an update for the main event's recurrence rule instead of a cancellation message
         else if ($event['_savemode'] == 'future' && $success !== false && $success !== true) {
           $event['_savemode'] = 'all';  // force event_save_success() to load master event
           $action = 'edit';
           $success = true;
         }
 
         // send iTIP reply that participant has declined the event
         if ($success && $event['_decline']) {
           $emails = $this->get_user_emails();
           foreach ($old['attendees'] as $i => $attendee) {
             if ($attendee['role'] == 'ORGANIZER')
               $organizer = $attendee;
             else if ($attendee['email'] && in_array(strtolower($attendee['email']), $emails)) {
               $old['attendees'][$i]['status'] = 'DECLINED';
               $reply_sender = $attendee['email'];
             }
           }
 
           if ($event['_savemode'] == 'future' && $event['id'] != $old['id']) {
             $old['thisandfuture'] = true;
           }
 
           $itip = $this->load_itip();
           $itip->set_sender_email($reply_sender);
           if ($organizer && $itip->send_itip_message($old, 'REPLY', $organizer, 'itipsubjectdeclined', 'itipmailbodydeclined'))
             $this->rc->output->command('display_message', $this->gettext(array('name' => 'sentresponseto', 'vars' => array('mailto' => $organizer['name'] ? $organizer['name'] : $organizer['email']))), 'confirmation');
           else
             $this->rc->output->command('display_message', $this->gettext('itipresponseerror'), 'error');
         }
         else if ($success) {
           $this->event_save_success($event, $old, $action, $success);
         }
         break;
 
       case "undo":
         // Restore deleted event
         $event  = $_SESSION['calendar_event_undo']['data'];
 
         if ($event)
           $success = $this->driver->restore_event($event);
 
         if ($success) {
           $this->rc->session->remove('calendar_event_undo');
           $this->rc->output->show_message('calendar.successrestore', 'confirmation');
           $got_msg = true;
           $reload = 2;
         }
 
         break;
 
       case "rsvp":
         $itip_sending  = $this->rc->config->get('calendar_itip_send_option', $this->defaults['calendar_itip_send_option']);
         $status        = rcube_utils::get_input_value('status', rcube_utils::INPUT_POST);
         $attendees     = rcube_utils::get_input_value('attendees', rcube_utils::INPUT_POST);
         $reply_comment = $event['comment'];
 
         $this->write_preprocess($event, 'edit');
         $ev = $this->driver->get_event($event);
         $ev['attendees'] = $event['attendees'];
         $ev['free_busy'] = $event['free_busy'];
         $ev['_savemode'] = $event['_savemode'];
 
         // send invitation to delegatee + add it as attendee
         if ($status == 'delegated' && $event['to']) {
           $itip = $this->load_itip();
           if ($itip->delegate_to($ev, $event['to'], (bool)$event['rsvp'], $attendees)) {
             $this->rc->output->show_message('calendar.itipsendsuccess', 'confirmation');
             $noreply = false;
           }
         }
 
         $event = $ev;
 
         // compose a list of attendees affected by this change
         $updated_attendees = array_filter(array_map(function($j) use ($event) {
           return $event['attendees'][$j];
         }, $attendees));
 
         if ($success = $this->driver->edit_rsvp($event, $status, $updated_attendees)) {
           $noreply = rcube_utils::get_input_value('noreply', rcube_utils::INPUT_GPC);
           $noreply = intval($noreply) || $status == 'needs-action' || $itip_sending === 0;
           $reload  = $event['calendar'] != $ev['calendar'] || $event['recurrence'] ? 2 : 1;
           $organizer = null;
           $emails = $this->get_user_emails();
 
           foreach ($event['attendees'] as $i => $attendee) {
             if ($attendee['role'] == 'ORGANIZER') {
               $organizer = $attendee;
             }
             else if ($attendee['email'] && in_array(strtolower($attendee['email']), $emails)) {
               $reply_sender = $attendee['email'];
             }
           }
 
           if (!$noreply) {
             $itip = $this->load_itip();
             $itip->set_sender_email($reply_sender);
             $event['comment'] = $reply_comment;
             $event['thisandfuture'] = $event['_savemode'] == 'future';
             if ($organizer && $itip->send_itip_message($event, 'REPLY', $organizer, 'itipsubject' . $status, 'itipmailbody' . $status))
               $this->rc->output->command('display_message', $this->gettext(array('name' => 'sentresponseto', 'vars' => array('mailto' => $organizer['name'] ? $organizer['name'] : $organizer['email']))), 'confirmation');
             else
               $this->rc->output->command('display_message', $this->gettext('itipresponseerror'), 'error');
           }
 
           // refresh all calendars
           if ($event['calendar'] != $ev['calendar']) {
             $this->rc->output->command('plugin.refresh_calendar', array('source' => null, 'refetch' => true));
             $reload = 0;
           }
         }
         break;
 
       case "dismiss":
         $event['ids'] = explode(',', $event['id']);
         $plugin = $this->rc->plugins->exec_hook('dismiss_alarms', $event);
         $success = $plugin['success'];
         foreach ($event['ids'] as $id) {
             if (strpos($id, 'cal:') === 0)
                 $success |= $this->driver->dismiss_alarm(substr($id, 4), $event['snooze']);
         }
         break;
 
       case "changelog":
         $data = $this->driver->get_event_changelog($event);
         if (is_array($data) && !empty($data)) {
           $lib = $this->lib;
           $dtformat = $this->rc->config->get('date_format') . ' ' . $this->rc->config->get('time_format');
           array_walk($data, function(&$change) use ($lib, $dtformat) {
             if ($change['date']) {
               $dt = $lib->adjust_timezone($change['date']);
               if ($dt instanceof DateTime)
                 $change['date'] = $this->rc->format_date($dt, $dtformat, false);
             }
           });
           $this->rc->output->command('plugin.render_event_changelog', $data);
         }
         else {
           $this->rc->output->command('plugin.render_event_changelog', false);
         }
         $got_msg = true;
         $reload = false;
         break;
 
       case "diff":
         $data = $this->driver->get_event_diff($event, $event['rev1'], $event['rev2']);
         if (is_array($data)) {
           // convert some properties, similar to self::_client_event()
           $lib = $this->lib;
           array_walk($data['changes'], function(&$change, $i) use ($event, $lib) {
             // convert date cols
             foreach (array('start','end','created','changed') as $col) {
               if ($change['property'] == $col) {
                 $change['old'] = $lib->adjust_timezone($change['old'], strlen($change['old']) == 10)->format('c');
                 $change['new'] = $lib->adjust_timezone($change['new'], strlen($change['new']) == 10)->format('c');
               }
             }
             // create textual representation for alarms and recurrence
             if ($change['property'] == 'alarms') {
               if (is_array($change['old']))
                 $change['old_'] = libcalendaring::alarm_text($change['old']);
               if (is_array($change['new']))
                 $change['new_'] = libcalendaring::alarm_text(array_merge((array)$change['old'], $change['new']));
             }
             if ($change['property'] == 'recurrence') {
               if (is_array($change['old']))
                 $change['old_'] = $lib->recurrence_text($change['old']);
               if (is_array($change['new']))
                 $change['new_'] = $lib->recurrence_text(array_merge((array)$change['old'], $change['new']));
             }
             if ($change['property'] == 'attachments') {
               if (is_array($change['old']))
                 $change['old']['classname'] = rcube_utils::file2class($change['old']['mimetype'], $change['old']['name']);
               if (is_array($change['new']))
                 $change['new']['classname'] = rcube_utils::file2class($change['new']['mimetype'], $change['new']['name']);
             }
             // compute a nice diff of description texts
             if ($change['property'] == 'description') {
               $change['diff_'] = libkolab::html_diff($change['old'], $change['new']);
             }
           });
           $this->rc->output->command('plugin.event_show_diff', $data);
         }
         else {
           $this->rc->output->command('display_message', $this->gettext('objectdiffnotavailable'), 'error');
         }
         $got_msg = true;
         $reload = false;
         break;
 
       case "show":
         if ($event = $this->driver->get_event_revison($event, $event['rev'])) {
           $this->rc->output->command('plugin.event_show_revision', $this->_client_event($event));
         }
         else {
           $this->rc->output->command('display_message', $this->gettext('objectnotfound'), 'error');
         }
         $got_msg = true;
         $reload = false;
         break;
 
       case "restore":
         if ($success = $this->driver->restore_event_revision($event, $event['rev'])) {
           $_event = $this->driver->get_event($event);
           $reload = $_event['recurrence'] ? 2 : 1;
           $this->rc->output->command('display_message', $this->gettext(array('name' => 'objectrestoresuccess', 'vars' => array('rev' => $event['rev']))), 'confirmation');
           $this->rc->output->command('plugin.close_history_dialog');
         }
         else {
           $this->rc->output->command('display_message', $this->gettext('objectrestoreerror'), 'error');
           $reload = 0;
         }
         $got_msg = true;
         break;
     }
 
     // show confirmation/error message
     if (!$got_msg) {
       if ($success)
         $this->rc->output->show_message('successfullysaved', 'confirmation');
       else
         $this->rc->output->show_message('calendar.errorsaving', 'error');
     }
 
     // unlock client
     $this->rc->output->command('plugin.unlock_saving');
 
     // update event object on the client or trigger a complete refretch if too complicated
     if ($reload) {
       $args = array('source' => $event['calendar']);
       if ($reload > 1)
         $args['refetch'] = true;
       else if ($success && $action != 'remove')
         $args['update'] = $this->_client_event($this->driver->get_event($event), true);
       $this->rc->output->command('plugin.refresh_calendar', $args);
     }
   }
 
   /**
    * Helper method sending iTip notifications after successful event updates
    */
   private function event_save_success(&$event, $old, $action, $success)
   {
     // $success is a new event ID
     if ($success !== true) {
       // send update notification on the main event
       if ($event['_savemode'] == 'future' && $event['_notify'] && $old['attendees'] && $old['recurrence_id']) {
         $master = $this->driver->get_event(array('id' => $old['recurrence_id'], 'calendar' => $old['calendar']), 0, true);
         unset($master['_instance'], $master['recurrence_date']);
 
         $sent = $this->notify_attendees($master, null, $action, $event['_comment'], false);
         if ($sent < 0)
           $this->rc->output->show_message('calendar.errornotifying', 'error');
 
         $event['attendees'] = $master['attendees'];  // this tricks us into the next if clause
       }
 
       // delete old reference if saved as new
       if ($event['_savemode'] == 'future' || $event['_savemode'] == 'new') {
         $old = null;
       }
 
       $event['id'] = $success;
       $event['_savemode'] = 'all';
     }
 
     // send out notifications
     if ($event['_notify'] && ($event['attendees'] || $old['attendees'])) {
       $_savemode = $event['_savemode'];
 
       // send notification for the main event when savemode is 'all'
       if ($action != 'remove' && $_savemode == 'all' && ($event['recurrence_id'] || $old['recurrence_id'] || ($old && $old['id'] != $event['id']))) {
         $event['id'] = $event['recurrence_id'] ?: ($old['recurrence_id'] ?: $old['id']);
         $event = $this->driver->get_event($event, 0, true);
         unset($event['_instance'], $event['recurrence_date']);
       }
       else {
         // make sure we have the complete record
         $event = $action == 'remove' ? $old : $this->driver->get_event($event, 0, true);
       }
 
       $event['_savemode'] = $_savemode;
 
       if ($old) {
         $old['thisandfuture'] = $_savemode == 'future';
       }
 
       // only notify if data really changed (TODO: do diff check on client already)
       if (!$old || $action == 'remove' || self::event_diff($event, $old)) {
         $sent = $this->notify_attendees($event, $old, $action, $event['_comment']);
         if ($sent > 0)
           $this->rc->output->show_message('calendar.itipsendsuccess', 'confirmation');
         else if ($sent < 0)
           $this->rc->output->show_message('calendar.errornotifying', 'error');
       }
     }
   }
 
   /**
    * Handler for load-requests from fullcalendar
    * This will return pure JSON formatted output
    */
   function load_events()
   {
     $events = $this->driver->load_events(
       rcube_utils::get_input_value('start', rcube_utils::INPUT_GET),
       rcube_utils::get_input_value('end', rcube_utils::INPUT_GET),
       ($query = rcube_utils::get_input_value('q', rcube_utils::INPUT_GET)),
       rcube_utils::get_input_value('source', rcube_utils::INPUT_GET)
     );
     echo $this->encode($events, !empty($query));
     exit;
   }
 
   /**
    * Handler for requests fetching event counts for calendars
    */
   public function count_events()
   {
     // don't update session on these requests (avoiding race conditions)
     $this->rc->session->nowrite = true;
 
     $start = rcube_utils::get_input_value('start', rcube_utils::INPUT_GET);
     if (!$start) {
       $start = new DateTime('today 00:00:00', $this->timezone);
       $start = $start->format('U');
     }
 
     $counts = $this->driver->count_events(
       rcube_utils::get_input_value('source', rcube_utils::INPUT_GET),
       $start,
       rcube_utils::get_input_value('end', rcube_utils::INPUT_GET)
     );
 
     $this->rc->output->command('plugin.update_counts', array('counts' => $counts));
   }
 
   /**
    * Load event data from an iTip message attachment
    */
   public function itip_events($msgref)
   {
     $path = explode('/', $msgref);
     $msg = array_pop($path);
     $mbox = join('/', $path);
     list($uid, $mime_id) = explode('#', $msg);
     $events = array();
 
     if ($event = $this->lib->mail_get_itip_object($mbox, $uid, $mime_id, 'event')) {
       $partstat = 'NEEDS-ACTION';
 /*
       $user_emails = $this->lib->get_user_emails();
       foreach ($event['attendees'] as $attendee) {
         if (in_array($attendee['email'], $user_emails)) {
           $partstat = $attendee['status'];
           break;
         }
       }
 */
       $event['id'] = $event['uid'];
       $event['temporary'] = true;
       $event['readonly'] = true;
       $event['calendar'] = '--invitation--itip';
       $event['className'] = 'fc-invitation-' . strtolower($partstat);
       $event['_mbox'] = $mbox;
       $event['_uid']  = $uid;
       $event['_part'] = $mime_id;
 
       $events[] = $this->_client_event($event, true);
 
       // add recurring instances
       if (!empty($event['recurrence'])) {
         foreach ($this->driver->get_recurring_events($event, $event['start']) as $recurring) {
           $recurring['temporary'] = true;
           $recurring['readonly'] = true;
           $recurring['calendar'] = '--invitation--itip';
           $events[] = $this->_client_event($recurring, true);
         }
       }
     }
 
     return $events;
   }
 
   /**
    * Handler for keep-alive requests
    * This will check for updated data in active calendars and sync them to the client
    */
   public function refresh($attr)
   {
      // refresh the entire calendar every 10th time to also sync deleted events
     if (rand(0,10) == 10) {
         $this->rc->output->command('plugin.refresh_calendar', array('refetch' => true));
         return;
     }
 
     $counts = array();
 
     foreach ($this->driver->list_calendars(calendar_driver::FILTER_ACTIVE) as $cal) {
       $events = $this->driver->load_events(
         rcube_utils::get_input_value('start', rcube_utils::INPUT_GPC),
         rcube_utils::get_input_value('end', rcube_utils::INPUT_GPC),
         rcube_utils::get_input_value('q', rcube_utils::INPUT_GPC),
         $cal['id'],
         1,
         $attr['last']
       );
 
       foreach ($events as $event) {
         $this->rc->output->command('plugin.refresh_calendar',
           array('source' => $cal['id'], 'update' => $this->_client_event($event)));
       }
 
       // refresh count for this calendar
       if ($cal['counts']) {
         $today = new DateTime('today 00:00:00', $this->timezone);
         $counts += $this->driver->count_events($cal['id'], $today->format('U'));
       }
     }
 
     if (!empty($counts)) {
       $this->rc->output->command('plugin.update_counts', array('counts' => $counts));
     }
   }
 
   /**
    * Handler for pending_alarms plugin hook triggered by the calendar module on keep-alive requests.
    * This will check for pending notifications and pass them to the client
    */
   public function pending_alarms($p)
   {
     $this->load_driver();
     $time = $p['time'] ?: time();
     if ($alarms = $this->driver->pending_alarms($time)) {
       foreach ($alarms as $alarm) {
         $alarm['id'] = 'cal:' . $alarm['id'];  // prefix ID with cal:
         $p['alarms'][] = $alarm;
       }
     }
 
     // get alarms for birthdays calendar
     if ($this->rc->config->get('calendar_contact_birthdays') && $this->rc->config->get('calendar_birthdays_alarm_type') == 'DISPLAY') {
       $cache = $this->rc->get_cache('calendar.birthdayalarms', 'db');
 
       foreach ($this->driver->load_birthday_events($time, $time + 86400 * 60) as $e) {
         $alarm = libcalendaring::get_next_alarm($e);
 
         // overwrite alarm time with snooze value (or null if dismissed)
         if ($dismissed = $cache->get($e['id']))
           $alarm['time'] = $dismissed['notifyat'];
 
         // add to list if alarm is set
         if ($alarm && $alarm['time'] && $alarm['time'] <= $time) {
           $e['id'] = 'cal:bday:' . $e['id'];
           $e['notifyat'] = $alarm['time'];
           $p['alarms'][] = $e;
         }
       }
     }
 
     return $p;
   }
 
   /**
    * Handler for alarm dismiss hook triggered by libcalendaring
    */
   public function dismiss_alarms($p)
   {
       $this->load_driver();
       foreach ((array)$p['ids'] as $id) {
           if (strpos($id, 'cal:bday:') === 0) {
               $p['success'] |= $this->driver->dismiss_birthday_alarm(substr($id, 9), $p['snooze']);
           }
           else if (strpos($id, 'cal:') === 0) {
               $p['success'] |= $this->driver->dismiss_alarm(substr($id, 4), $p['snooze']);
           }
       }
 
       return $p;
   }
 
   /**
    * Handler for check-recent requests which are accidentally sent to calendar taks
    */
   function check_recent()
   {
     // NOP
     $this->rc->output->send();
   }
 
   /**
    * Hook triggered when a contact is saved
    */
   function contact_update($p)
   {
     // clear birthdays calendar cache
     if (!empty($p['record']['birthday'])) {
       $cache = $this->rc->get_cache('calendar.birthdays', 'db');
       $cache->remove();
     }
   }
 
   /**
    *
    */
   function import_events()
   {
     // Upload progress update
     if (!empty($_GET['_progress'])) {
       rcube_upload_progress();
     }
 
     @set_time_limit(0);
 
     // process uploaded file if there is no error
     $err = $_FILES['_data']['error'];
 
     if (!$err && $_FILES['_data']['tmp_name']) {
       $calendar   = rcube_utils::get_input_value('calendar', rcube_utils::INPUT_GPC);
       $rangestart = $_REQUEST['_range'] ? date_create("now -" . intval($_REQUEST['_range']) . " months") : 0;
 
       // extract zip file
       if ($_FILES['_data']['type'] == 'application/zip') {
         $count = 0;
         if (class_exists('ZipArchive', false)) {
           $zip = new ZipArchive();
           if ($zip->open($_FILES['_data']['tmp_name'])) {
             $randname = uniqid('zip-' . session_id(), true);
             $tmpdir = slashify($this->rc->config->get('temp_dir', sys_get_temp_dir())) . $randname;
             mkdir($tmpdir, 0700);
 
             // extract each ical file from the archive and import it
             for ($i = 0; $i < $zip->numFiles; $i++) { 
               $filename = $zip->getNameIndex($i);
               if (preg_match('/\.ics$/i', $filename)) {
                 $tmpfile = $tmpdir . '/' . basename($filename);
                 if (copy('zip://' . $_FILES['_data']['tmp_name'] . '#'.$filename, $tmpfile)) {
                   $count += $this->import_from_file($tmpfile, $calendar, $rangestart, $errors);
                   unlink($tmpfile);
                 }
               }
             }
 
             rmdir($tmpdir);
             $zip->close();
           }
           else {
             $errors = 1;
             $msg = 'Failed to open zip file.';
           }
         }
         else {
           $errors = 1;
           $msg = 'Zip files are not supported for import.';
         }
       }
       else {
         // attempt to import teh uploaded file directly
         $count = $this->import_from_file($_FILES['_data']['tmp_name'], $calendar, $rangestart, $errors);
       }
 
       if ($count) {
         $this->rc->output->command('display_message', $this->gettext(array('name' => 'importsuccess', 'vars' => array('nr' => $count))), 'confirmation');
         $this->rc->output->command('plugin.import_success', array('source' => $calendar, 'refetch' => true));
       }
       else if (!$errors) {
         $this->rc->output->command('display_message', $this->gettext('importnone'), 'notice');
         $this->rc->output->command('plugin.import_success', array('source' => $calendar));
       }
       else {
         $this->rc->output->command('plugin.import_error', array('message' => $this->gettext('importerror') . ($msg ? ': ' . $msg : '')));
       }
     }
     else {
       if ($err == UPLOAD_ERR_INI_SIZE || $err == UPLOAD_ERR_FORM_SIZE) {
-        $msg = rcube_label(array('name' => 'filesizeerror', 'vars' => array(
+        $msg = $this->gettext(array('name' => 'filesizeerror', 'vars' => array(
             'size' => show_bytes(parse_bytes(ini_get('upload_max_filesize'))))));
       }
       else {
-        $msg = rcube_label('fileuploaderror');
+        $msg = $this->gettext('fileuploaderror');
       }
 
       $this->rc->output->command('plugin.import_error', array('message' => $msg));
     }
 
     $this->rc->output->send('iframe');
   }
 
   /**
    * Helper function to parse and import a single .ics file
    */
   private function import_from_file($filepath, $calendar, $rangestart, &$errors)
   {
     $user_email = $this->rc->user->get_username();
 
     $ical = $this->get_ical();
     $errors = !$ical->fopen($filepath);
     $count = $i = 0;
     foreach ($ical as $event) {
       // keep the browser connection alive on long import jobs
       if (++$i > 100 && $i % 100 == 0) {
           echo "<!-- -->";
           ob_flush();
       }
 
       // TODO: correctly handle recurring events which start before $rangestart
       if ($event['end'] < $rangestart && (!$event['recurrence'] || ($event['recurrence']['until'] && $event['recurrence']['until'] < $rangestart)))
         continue;
 
       $event['_owner'] = $user_email;
       $event['calendar'] = $calendar;
       if ($this->driver->new_event($event)) {
         $count++;
       }
       else {
         $errors++;
       }
     }
 
     return $count;
   }
 
 
   /**
    * Construct the ics file for exporting events to iCalendar format;
    */
   function export_events($terminate = true)
   {
     $start = rcube_utils::get_input_value('start', rcube_utils::INPUT_GET);
     $end   = rcube_utils::get_input_value('end', rcube_utils::INPUT_GET);
 
     if (!isset($start))
       $start = 'today -1 year';
     if (!is_numeric($start))
       $start = strtotime($start . ' 00:00:00');
     if (!$end)
       $end = 'today +10 years';
     if (!is_numeric($end))
       $end = strtotime($end . ' 23:59:59');
 
     $event_id    = rcube_utils::get_input_value('id', rcube_utils::INPUT_GET);
     $attachments = rcube_utils::get_input_value('attachments', rcube_utils::INPUT_GET);
     $calid = $filename = rcube_utils::get_input_value('source', rcube_utils::INPUT_GET);
 
     $calendars = $this->driver->list_calendars();
     $events = array();
 
     if ($calendars[$calid]) {
       $filename = $calendars[$calid]['name'] ? $calendars[$calid]['name'] : $calid;
       $filename = asciiwords(html_entity_decode($filename));  // to 7bit ascii
       if (!empty($event_id)) {
         if ($event = $this->driver->get_event(array('calendar' => $calid, 'id' => $event_id), 0, true)) {
           if ($event['recurrence_id']) {
             $event = $this->driver->get_event(array('calendar' => $calid, 'id' => $event['recurrence_id']), 0, true);
           }
           $events = array($event);
           $filename = asciiwords($event['title']);
           if (empty($filename))
             $filename = 'event';
         }
       }
       else {
          $events = $this->driver->load_events($start, $end, null, $calid, 0);
          if (empty($filename))
            $filename = $calid;
       }
     }
 
     header("Content-Type: text/calendar");
     header("Content-Disposition: inline; filename=".$filename.'.ics');
 
     $this->get_ical()->export($events, '', true, $attachments ? array($this->driver, 'get_attachment_body') : null);
 
     if ($terminate)
       exit;
   }
 
 
   /**
    * Handler for iCal feed requests
    */
   function ical_feed_export()
   {
     $session_exists = !empty($_SESSION['user_id']);
 
     // process HTTP auth info
     if (!empty($_SERVER['PHP_AUTH_USER']) && isset($_SERVER['PHP_AUTH_PW'])) {
       $_POST['_user'] = $_SERVER['PHP_AUTH_USER']; // used for rcmail::autoselect_host()
       $auth = $this->rc->plugins->exec_hook('authenticate', array(
         'host' => $this->rc->autoselect_host(),
         'user' => trim($_SERVER['PHP_AUTH_USER']),
         'pass' => $_SERVER['PHP_AUTH_PW'],
         'cookiecheck' => true,
         'valid' => true,
       ));
       if ($auth['valid'] && !$auth['abort'])
         $this->rc->login($auth['user'], $auth['pass'], $auth['host']);
     }
 
     // require HTTP auth
     if (empty($_SESSION['user_id'])) {
       header('WWW-Authenticate: Basic realm="Roundcube Calendar"');
       header('HTTP/1.0 401 Unauthorized');
       exit;
     }
 
     // decode calendar feed hash
     $format = 'ics';
     $calhash = rcube_utils::get_input_value('_cal', rcube_utils::INPUT_GET);
     if (preg_match(($suff_regex = '/\.([a-z0-9]{3,5})$/i'), $calhash, $m)) {
       $format = strtolower($m[1]);
       $calhash = preg_replace($suff_regex, '', $calhash);
     }
 
     if (!strpos($calhash, ':'))
       $calhash = base64_decode($calhash);
 
     list($user, $_GET['source']) = explode(':', $calhash, 2);
 
     // sanity check user
     if ($this->rc->user->get_username() == $user) {
       $this->load_driver();
       $this->export_events(false);
     }
     else {
       header('HTTP/1.0 404 Not Found');
     }
 
     // don't save session data
     if (!$session_exists)
       session_destroy();
     exit;
   }
 
 
   /**
    *
    */
   function load_settings()
   {
     $this->lib->load_settings();
     $this->defaults += $this->lib->defaults;
 
     $settings = array();
 
     // configuration
     $settings['default_calendar'] = $this->rc->config->get('calendar_default_calendar');
     $settings['default_view'] = (string)$this->rc->config->get('calendar_default_view', $this->defaults['calendar_default_view']);
     $settings['date_agenda'] = (string)$this->rc->config->get('calendar_date_agenda', $this->defaults['calendar_date_agenda']);
 
     $settings['timeslots'] = (int)$this->rc->config->get('calendar_timeslots', $this->defaults['calendar_timeslots']);
     $settings['first_day'] = (int)$this->rc->config->get('calendar_first_day', $this->defaults['calendar_first_day']);
     $settings['first_hour'] = (int)$this->rc->config->get('calendar_first_hour', $this->defaults['calendar_first_hour']);
     $settings['work_start'] = (int)$this->rc->config->get('calendar_work_start', $this->defaults['calendar_work_start']);
     $settings['work_end'] = (int)$this->rc->config->get('calendar_work_end', $this->defaults['calendar_work_end']);
     $settings['agenda_range'] = (int)$this->rc->config->get('calendar_agenda_range', $this->defaults['calendar_agenda_range']);
     $settings['agenda_sections'] = $this->rc->config->get('calendar_agenda_sections', $this->defaults['calendar_agenda_sections']);
     $settings['event_coloring'] = (int)$this->rc->config->get('calendar_event_coloring', $this->defaults['calendar_event_coloring']);
     $settings['time_indicator'] = (int)$this->rc->config->get('calendar_time_indicator', $this->defaults['calendar_time_indicator']);
     $settings['invite_shared'] = (int)$this->rc->config->get('calendar_allow_invite_shared', $this->defaults['calendar_allow_invite_shared']);
     $settings['invitation_calendars'] = (bool)$this->rc->config->get('kolab_invitation_calendars', false);
     $settings['itip_notify'] = (int)$this->rc->config->get('calendar_itip_send_option', $this->defaults['calendar_itip_send_option']);
 
     // get user identity to create default attendee
     if ($this->ui->screen == 'calendar') {
       foreach ($this->rc->user->list_emails() as $rec) {
         if (!$identity)
           $identity = $rec;
         $identity['emails'][] = $rec['email'];
         $settings['identities'][$rec['identity_id']] = $rec['email'];
       }
       $identity['emails'][] = $this->rc->user->get_username();
       $settings['identity'] = array('name' => $identity['name'], 'email' => strtolower($identity['email']), 'emails' => ';' . strtolower(join(';', $identity['emails'])));
     }
 
     return $settings;
   }
 
   /**
    * Encode events as JSON
    *
    * @param  array  Events as array
    * @param  boolean Add CSS class names according to calendar and categories
    * @return string JSON encoded events
    */
   function encode($events, $addcss = false)
   {
     $json = array();
     foreach ($events as $event) {
       $json[] = $this->_client_event($event, $addcss);
     }
     return json_encode($json);
   }
 
   /**
    * Convert an event object to be used on the client
    */
   private function _client_event($event, $addcss = false)
   {
     // compose a human readable strings for alarms_text and recurrence_text
     if ($event['valarms']) {
       $event['alarms_text'] = libcalendaring::alarms_text($event['valarms']);
       $event['valarms'] = libcalendaring::to_client_alarms($event['valarms']);
     }
     if ($event['recurrence']) {
       $event['recurrence_text'] = $this->lib->recurrence_text($event['recurrence']);
       $event['recurrence'] = $this->lib->to_client_recurrence($event['recurrence'], $event['allday']);
       unset($event['recurrence_date']);
     }
 
     foreach ((array)$event['attachments'] as $k => $attachment) {
       $event['attachments'][$k]['classname'] = rcube_utils::file2class($attachment['mimetype'], $attachment['name']);
     }
 
     // convert link URIs references into structs
     if (array_key_exists('links', $event)) {
       foreach ((array)$event['links'] as $i => $link) {
         if (strpos($link, 'imap://') === 0 && ($msgref = $this->driver->get_message_reference($link))) {
           $event['links'][$i] = $msgref;
         }
       }
     }
 
     // check for organizer in attendees list
     $organizer = null;
     foreach ((array)$event['attendees'] as $i => $attendee) {
       if ($attendee['role'] == 'ORGANIZER') {
         $organizer = $attendee;
       }
       if ($attendee['status'] == 'DELEGATED' && $attendee['rsvp'] == false) {
         $event['attendees'][$i]['noreply'] = true;
       }
       else {
         unset($event['attendees'][$i]['noreply']);
       }
     }
 
     if ($organizer === null && !empty($event['organizer'])) {
       $organizer = $event['organizer'];
       $organizer['role'] = 'ORGANIZER';
       if (!is_array($event['attendees']))
         $event['attendees'] = array();
       array_unshift($event['attendees'], $organizer);
     }
 
     // Convert HTML description into plain text
     if ($this->is_html($event)) {
       $h2t = new rcube_html2text($event['description'], false, true, 0);
       $event['description'] = trim($h2t->get_text());
     }
 
     // mapping url => vurl because of the fullcalendar client script
     $event['vurl'] = $event['url'];
     unset($event['url']);
 
     return array(
       '_id'   => $event['calendar'] . ':' . $event['id'],  // unique identifier for fullcalendar
       'start' => $this->lib->adjust_timezone($event['start'], $event['allday'])->format('c'),
       'end'   => $this->lib->adjust_timezone($event['end'], $event['allday'])->format('c'),
       // 'changed' might be empty for event recurrences (Bug #2185)
       'changed' => $event['changed'] ? $this->lib->adjust_timezone($event['changed'])->format('c') : null,
       'created' => $event['created'] ? $this->lib->adjust_timezone($event['created'])->format('c') : null,
       'title'       => strval($event['title']),
       'description' => strval($event['description']),
       'location'    => strval($event['location']),
       'className'   => ($addcss ? 'fc-event-cal-'.asciiwords($event['calendar'], true).' ' : '') .
           'fc-event-cat-' . asciiwords(strtolower(join('-', (array)$event['categories'])), true) .
           rtrim(' ' . $event['className']),
       'allDay'      => ($event['allday'] == 1),
     ) + $event;
   }
 
 
   /**
    * Generate a unique identifier for an event
    */
   public function generate_uid()
   {
     return strtoupper(md5(time() . uniqid(rand())) . '-' . substr(md5($this->rc->user->get_username()), 0, 16));
   }
 
 
   /**
    * TEMPORARY: generate random event data for testing
    * Create events by opening http://<roundcubeurl>/?_task=calendar&_action=randomdata&_num=500&_date=2014-08-01&_dev=120
    */
   public function generate_randomdata()
   {
     @set_time_limit(0);
 
     $num   = $_REQUEST['_num'] ? intval($_REQUEST['_num']) : 100;
     $date  = $_REQUEST['_date'] ?: 'now';
     $dev   = $_REQUEST['_dev'] ?: 30;
     $cats  = array_keys($this->driver->list_categories());
     $cals  = $this->driver->list_calendars(calendar_driver::FILTER_ACTIVE);
     $count = 0;
 
     while ($count++ < $num) {
       $spread = intval($dev) * 86400; // days
       $refdate = strtotime($date);
       $start = round(($refdate + rand(-$spread, $spread)) / 600) * 600;
       $duration = round(rand(30, 360) / 30) * 30 * 60;
       $allday = rand(0,20) > 18;
       $alarm = rand(-30,12) * 5;
       $fb = rand(0,2);
       
       if (date('G', $start) > 23)
         $start -= 3600;
       
       if ($allday) {
         $start = strtotime(date('Y-m-d 00:00:00', $start));
         $duration = 86399;
       }
       
       $title = '';
       $len = rand(2, 12);
       $words = explode(" ", "The Hough transform is named after Paul Hough who patented the method in 1962. It is a technique which can be used to isolate features of a particular shape within an image. Because it requires that the desired features be specified in some parametric form, the classical Hough transform is most commonly used for the de- tection of regular curves such as lines, circles, ellipses, etc. A generalized Hough transform can be employed in applications where a simple analytic description of a feature(s) is not possible. Due to the computational complexity of the generalized Hough algorithm, we restrict the main focus of this discussion to the classical Hough transform. Despite its domain restrictions, the classical Hough transform (hereafter referred to without the classical prefix ) retains many applications, as most manufac- tured parts (and many anatomical parts investigated in medical imagery) contain feature boundaries which can be described by regular curves. The main advantage of the Hough transform technique is that it is tolerant of gaps in feature boundary descriptions and is relatively unaffected by image noise.");
 //      $chars = "!# abcdefghijklmnopqrstuvwxyz ABCDEFGHIJKLMNOPQRSTUVWXYZ 1234567890";
       for ($i = 0; $i < $len; $i++)
         $title .= $words[rand(0,count($words)-1)] . " ";
       
       $this->driver->new_event(array(
         'uid' => $this->generate_uid(),
         'start' => new DateTime('@'.$start),
         'end' => new DateTime('@'.($start + $duration)),
         'allday' => $allday,
         'title' => rtrim($title),
         'free_busy' => $fb == 2 ? 'outofoffice' : ($fb ? 'busy' : 'free'),
         'categories' => $cats[array_rand($cats)],
         'calendar' => array_rand($cals),
         'alarms' => $alarm > 0 ? "-{$alarm}M:DISPLAY" : '',
         'priority' => rand(0,9),
       ));
     }
     
     $this->rc->output->redirect('');
   }
 
   /**
    * Handler for attachments upload
    */
   public function attachment_upload()
   {
     $this->lib->attachment_upload(self::SESSION_KEY, 'cal-');
   }
 
   /**
    * Handler for attachments download/displaying
    */
   public function attachment_get()
   {
     // show loading page
     if (!empty($_GET['_preload'])) {
         return $this->lib->attachment_loading_page();
     }
 
     $event_id = rcube_utils::get_input_value('_event', rcube_utils::INPUT_GPC);
     $calendar = rcube_utils::get_input_value('_cal', rcube_utils::INPUT_GPC);
     $id       = rcube_utils::get_input_value('_id', rcube_utils::INPUT_GPC);
     $rev      = rcube_utils::get_input_value('_rev', rcube_utils::INPUT_GPC);
 
     $event = array('id' => $event_id, 'calendar' => $calendar, 'rev' => $rev);
     $attachment = $this->driver->get_attachment($id, $event);
 
     // show part page
     if (!empty($_GET['_frame'])) {
         $this->lib->attachment = $attachment;
         $this->register_handler('plugin.attachmentframe', array($this->lib, 'attachment_frame'));
         $this->register_handler('plugin.attachmentcontrols', array($this->lib, 'attachment_header'));
         $this->rc->output->send('calendar.attachment');
     }
     // deliver attachment content
     else if ($attachment) {
         $attachment['body'] = $this->driver->get_attachment_body($id, $event);
         $this->lib->attachment_get($attachment);
     }
 
     // if we arrive here, the requested part was not found
     header('HTTP/1.1 404 Not Found');
     exit;
   }
 
   /**
    * Determine whether the given event description is HTML formatted
    */
   private function is_html($event)
   {
       // check for opening and closing <html> or <body> tags
       return (preg_match('/<(html|body)(\s+[a-z]|>)/', $event['description'], $m) && strpos($event['description'], '</'.$m[1].'>') > 0);
   }
 
   /**
    * Prepares new/edited event properties before save
    */
   private function write_preprocess(&$event, $action)
   {
     // convert dates into DateTime objects in user's current timezone
     $event['start'] = new DateTime($event['start'], $this->timezone);
     $event['end'] = new DateTime($event['end'], $this->timezone);
     $event['allday'] = (bool)$event['allday'];
 
     // start/end is all we need for 'move' action (#1480)
     if ($action == 'move') {
       return;
     }
 
     // convert the submitted recurrence settings
     if (is_array($event['recurrence'])) {
       $event['recurrence'] = $this->lib->from_client_recurrence($event['recurrence'], $event['start']);
     }
 
     // convert the submitted alarm values
     if ($event['valarms']) {
       $event['valarms'] = libcalendaring::from_client_alarms($event['valarms']);
     }
 
     $attachments = array();
     $eventid     = 'cal-'.$event['id'];
 
     if (is_array($_SESSION[self::SESSION_KEY]) && $_SESSION[self::SESSION_KEY]['id'] == $eventid) {
       if (!empty($_SESSION[self::SESSION_KEY]['attachments'])) {
         foreach ($_SESSION[self::SESSION_KEY]['attachments'] as $id => $attachment) {
           if (is_array($event['attachments']) && in_array($id, $event['attachments'])) {
             $attachments[$id] = $this->rc->plugins->exec_hook('attachment_get', $attachment);
           }
         }
       }
     }
 
     $event['attachments'] = $attachments;
 
     // convert link references into simple URIs
     if (array_key_exists('links', $event)) {
       $event['links'] = array_map(function($link) {
           return is_array($link) ? $link['uri'] : strval($link);
         }, (array)$event['links']);
     }
 
     // check for organizer in attendees
     if ($action == 'new' || $action == 'edit') {
       if (!$event['attendees'])
         $event['attendees'] = array();
 
       $emails = $this->get_user_emails();
       $organizer = $owner = false;
       foreach ((array)$event['attendees'] as $i => $attendee) {
         if ($attendee['role'] == 'ORGANIZER')
           $organizer = $i;
         if ($attendee['email'] == in_array(strtolower($attendee['email']), $emails))
           $owner = $i;
         if (!isset($attendee['rsvp']))
           $event['attendees'][$i]['rsvp'] = true;
         else if (is_string($attendee['rsvp']))
           $event['attendees'][$i]['rsvp'] = $attendee['rsvp'] == 'true' || $attendee['rsvp'] == '1';
       }
 
       // set new organizer identity
       if ($organizer !== false && !empty($event['_identity']) && ($identity = $this->rc->user->get_identity($event['_identity']))) {
         $event['attendees'][$organizer]['name'] = $identity['name'];
         $event['attendees'][$organizer]['email'] = $identity['email'];
       }
 
       // set owner as organizer if yet missing
       if ($organizer === false && $owner !== false) {
         $event['attendees'][$owner]['role'] = 'ORGANIZER';
         unset($event['attendees'][$owner]['rsvp']);
       }
     }
 
     // mapping url => vurl because of the fullcalendar client script
     if (array_key_exists('vurl', $event)) {
       $event['url'] = $event['vurl'];
       unset($event['vurl']);
     }
   }
 
   /**
    * Releases some resources after successful event save
    */
   private function cleanup_event(&$event)
   {
     // remove temp. attachment files
     if (!empty($_SESSION[self::SESSION_KEY]) && ($eventid = $_SESSION[self::SESSION_KEY]['id'])) {
       $this->rc->plugins->exec_hook('attachments_cleanup', array('group' => $eventid));
       $this->rc->session->remove(self::SESSION_KEY);
     }
   }
 
   /**
    * Send out an invitation/notification to all event attendees
    */
   private function notify_attendees($event, $old, $action = 'edit', $comment = null, $rsvp = null)
   {
     if ($action == 'remove' || ($event['status'] == 'CANCELLED' && $old['status'] != $event['status'])) {
       $event['cancelled'] = true;
       $is_cancelled = true;
     }
 
     if ($rsvp === null)
       $rsvp = !$old || $event['sequence'] > $old['sequence'];
 
     $itip = $this->load_itip();
     $emails = $this->get_user_emails();
     $itip_notify = (int)$this->rc->config->get('calendar_itip_send_option', $this->defaults['calendar_itip_send_option']);
 
     // add comment to the iTip attachment
     $event['comment'] = $comment;
 
     // set a valid recurrence-id if this is a recurrence instance
     libcalendaring::identify_recurrence_instance($event);
 
     // compose multipart message using PEAR:Mail_Mime
     $method = $action == 'remove' ? 'CANCEL' : 'REQUEST';
     $message = $itip->compose_itip_message($event, $method, $rsvp);
 
     // list existing attendees from $old event
     $old_attendees = array();
     foreach ((array)$old['attendees'] as $attendee) {
       $old_attendees[] = $attendee['email'];
     }
 
     // send to every attendee
     $sent = 0; $current = array();
     foreach ((array)$event['attendees'] as $attendee) {
       $current[] = strtolower($attendee['email']);
       
       // skip myself for obvious reasons
       if (!$attendee['email'] || in_array(strtolower($attendee['email']), $emails))
         continue;
 
       // skip if notification is disabled for this attendee
       if ($attendee['noreply'] && $itip_notify & 2)
         continue;
 
       // skip if this attendee has delegated and set RSVP=FALSE
       if ($attendee['status'] == 'DELEGATED' && $attendee['rsvp'] === false)
         continue;
 
       // which template to use for mail text
       $is_new = !in_array($attendee['email'], $old_attendees);
       $is_rsvp = $is_new || $event['sequence'] > $old['sequence'];
       $bodytext = $is_cancelled ? 'eventcancelmailbody' : ($is_new ? 'invitationmailbody' : 'eventupdatemailbody');
       $subject  = $is_cancelled ? 'eventcancelsubject'  : ($is_new ? 'invitationsubject' : ($event['title'] ? 'eventupdatesubject':'eventupdatesubjectempty'));
 
       $event['comment'] = $comment;
 
       // finally send the message
       if ($itip->send_itip_message($event, $method, $attendee, $subject, $bodytext, $message, $is_rsvp))
         $sent++;
       else
         $sent = -100;
     }
 
     // TODO: on change of a recurring (main) event, also send updates to differing attendess of recurrence exceptions
 
     // send CANCEL message to removed attendees
     foreach ((array)$old['attendees'] as $attendee) {
       if ($attendee['role'] == 'ORGANIZER' || !$attendee['email'] || in_array(strtolower($attendee['email']), $current))
         continue;
 
       $vevent = $old;
       $vevent['cancelled'] = $is_cancelled;
       $vevent['attendees'] = array($attendee);
       $vevent['comment']   = $comment;
       if ($itip->send_itip_message($vevent, 'CANCEL', $attendee, 'eventcancelsubject', 'eventcancelmailbody'))
         $sent++;
       else
         $sent = -100;
     }
 
     return $sent;
   }
 
   /**
    * Echo simple free/busy status text for the given user and time range
    */
   public function freebusy_status()
   {
     $email = rcube_utils::get_input_value('email', rcube_utils::INPUT_GPC);
     $start = rcube_utils::get_input_value('start', rcube_utils::INPUT_GPC);
     $end   = rcube_utils::get_input_value('end', rcube_utils::INPUT_GPC);
 
     // convert dates into unix timestamps
     if (!empty($start) && !is_numeric($start)) {
       $dts = new DateTime($start, $this->timezone);
       $start = $dts->format('U');
     }
     if (!empty($end) && !is_numeric($end)) {
       $dte = new DateTime($end, $this->timezone);
       $end = $dte->format('U');
     }
     
     if (!$start) $start = time();
     if (!$end) $end = $start + 3600;
     
     $fbtypemap = array(calendar::FREEBUSY_UNKNOWN => 'UNKNOWN', calendar::FREEBUSY_FREE => 'FREE', calendar::FREEBUSY_BUSY => 'BUSY', calendar::FREEBUSY_TENTATIVE => 'TENTATIVE', calendar::FREEBUSY_OOF => 'OUT-OF-OFFICE');
     $status = 'UNKNOWN';
     
     // if the backend has free-busy information
     $fblist = $this->driver->get_freebusy_list($email, $start, $end);
     if (is_array($fblist)) {
       $status = 'FREE';
       
       foreach ($fblist as $slot) {
         list($from, $to, $type) = $slot;
         if ($from < $end && $to > $start) {
           $status = isset($type) && $fbtypemap[$type] ? $fbtypemap[$type] : 'BUSY';
           break;
         }
       }
     }
     
     // let this information be cached for 5min
     send_future_expire_header(300);
     
     echo $status;
     exit;
   }
   
   /**
    * Return a list of free/busy time slots within the given period
    * Echo data in JSON encoding
    */
   public function freebusy_times()
   {
     $email = rcube_utils::get_input_value('email', rcube_utils::INPUT_GPC);
     $start = rcube_utils::get_input_value('start', rcube_utils::INPUT_GPC);
     $end   = rcube_utils::get_input_value('end', rcube_utils::INPUT_GPC);
     $interval  = intval(rcube_utils::get_input_value('interval', rcube_utils::INPUT_GPC));
     $strformat = $interval > 60 ? 'Ymd' : 'YmdHis';
 
     // convert dates into unix timestamps
     if (!empty($start) && !is_numeric($start)) {
       $dts = rcube_utils::anytodatetime($start, $this->timezone);
       $start = $dts ? $dts->format('U') : null;
     }
     if (!empty($end) && !is_numeric($end)) {
       $dte = rcube_utils::anytodatetime($end, $this->timezone);
       $end = $dte ? $dte->format('U') : null;
     }
 
     if (!$start) $start = time();
     if (!$end)   $end = $start + 86400 * 30;
     if (!$interval) $interval = 60;  // 1 hour
     
     if (!$dte) {
       $dts = new DateTime('@'.$start);
       $dts->setTimezone($this->timezone);
     }
     
     $fblist = $this->driver->get_freebusy_list($email, $start, $end);
     $slots = array();
     
     // build a list from $start till $end with blocks representing the fb-status
     for ($s = 0, $t = $start; $t <= $end; $s++) {
       $status = self::FREEBUSY_UNKNOWN;
       $t_end = $t + $interval * 60;
       $dt = new DateTime('@'.$t);
       $dt->setTimezone($this->timezone);
 
       // determine attendee's status
       if (is_array($fblist)) {
         $status = self::FREEBUSY_FREE;
         foreach ($fblist as $slot) {
           list($from, $to, $type) = $slot;
 
           // check for possible all-day times
           if (gmdate('His', $from) == '000000' && gmdate('His', $to) == '235959') {
               // shift into the user's timezone for sane matching
               $from -= $this->gmt_offset;
               $to   -= $this->gmt_offset;
           }
 
           if ($from < $t_end && $to > $t) {
             $status = isset($type) ? $type : self::FREEBUSY_BUSY;
             if ($status == self::FREEBUSY_BUSY)  // can't get any worse :-)
               break;
           }
         }
       }
       
       $slots[$s] = $status;
       $times[$s] = intval($dt->format($strformat));
       $t = $t_end;
     }
     
     $dte = new DateTime('@'.$t_end);
     $dte->setTimezone($this->timezone);
     
     // let this information be cached for 5min
     send_future_expire_header(300);
     
     echo json_encode(array(
       'email' => $email,
       'start' => $dts->format('c'),
       'end'   => $dte->format('c'),
       'interval' => $interval,
       'slots' => $slots,
       'times' => $times,
     ));
     exit;
   }
 
   /**
    * Handler for printing calendars
    */
   public function print_view()
   {
     $title = $this->gettext('print');
 
     $view = rcube_utils::get_input_value('view', rcube_utils::INPUT_GPC);
     if (!in_array($view, array('agendaWeek', 'agendaDay', 'month', 'table')))
       $view = 'agendaDay';
 
     $this->rc->output->set_env('view',$view);
 
     if ($date = rcube_utils::get_input_value('date', rcube_utils::INPUT_GPC))
       $this->rc->output->set_env('date', $date);
 
     if ($range = rcube_utils::get_input_value('range', rcube_utils::INPUT_GPC))
       $this->rc->output->set_env('listRange', intval($range));
 
     if (isset($_REQUEST['sections']))
       $this->rc->output->set_env('listSections', rcube_utils::get_input_value('sections', rcube_utils::INPUT_GPC));
 
     if ($search = rcube_utils::get_input_value('search', rcube_utils::INPUT_GPC)) {
       $this->rc->output->set_env('search', $search);
       $title .= ' "' . $search . '"';
     }
 
     // Add CSS stylesheets to the page header
     $skin_path = $this->local_skin_path();
     $this->include_stylesheet($skin_path . '/fullcalendar.css');
     $this->include_stylesheet($skin_path . '/print.css');
     
     // Add JS files to the page header
     $this->include_script('print.js');
     $this->include_script('lib/js/fullcalendar.js');
     
     $this->register_handler('plugin.calendar_css', array($this->ui, 'calendar_css'));
     $this->register_handler('plugin.calendar_list', array($this->ui, 'calendar_list'));
     
     $this->rc->output->set_pagetitle($title);
     $this->rc->output->send("calendar.print");
   }
 
   /**
    *
    */
   public function get_inline_ui()
   {
     foreach (array('save','cancel','savingdata') as $label)
       $texts['calendar.'.$label] = $this->gettext($label);
     
     $texts['calendar.new_event'] = $this->gettext('createfrommail');
     
     $this->ui->init_templates();
     $this->ui->calendar_list();  # set env['calendars']
     echo $this->api->output->parse('calendar.eventedit', false, false);
     echo html::tag('script', array('type' => 'text/javascript'),
       "rcmail.set_env('calendars', " . json_encode($this->api->output->env['calendars']) . ");\n".
       "rcmail.set_env('deleteicon', '" . $this->api->output->env['deleteicon'] . "');\n".
       "rcmail.set_env('cancelicon', '" . $this->api->output->env['cancelicon'] . "');\n".
       "rcmail.set_env('loadingicon', '" . $this->api->output->env['loadingicon'] . "');\n".
       "rcmail.gui_object('attachmentlist', '"  . $this->ui->attachmentlist_id . "');\n".
       "rcmail.add_label(" . json_encode($texts) . ");\n"
     );
     exit;
   }
 
   /**
    * Compare two event objects and return differing properties
    *
    * @param array Event A
    * @param array Event B
    * @return array List of differing event properties
    */
   public static function event_diff($a, $b)
   {
     $diff = array();
     $ignore = array('changed' => 1, 'attachments' => 1);
     foreach (array_unique(array_merge(array_keys($a), array_keys($b))) as $key) {
       if (!$ignore[$key] && $key[0] != '_' && $a[$key] != $b[$key])
         $diff[] = $key;
     }
     
     // only compare number of attachments
     if (count($a['attachments']) != count($b['attachments']))
       $diff[] = 'attachments';
     
     return $diff;
   }
 
   /**
    * Update attendee properties on the given event object
    *
    * @param array The event object to be altered
    * @param array List of hash arrays each represeting an updated/added attendee
    */
   public static function merge_attendee_data(&$event, $attendees, $removed = null)
   {
     if (!empty($attendees) && !is_array($attendees[0])) {
       $attendees = array($attendees);
     }
 
     foreach ($attendees as $attendee) {
       $found = false;
 
       foreach ($event['attendees'] as $i => $candidate) {
         if ($candidate['email'] == $attendee['email']) {
           $event['attendees'][$i] = $attendee;
           $found = true;
           break;
         }
       }
 
       if (!$found) {
         $event['attendees'][] = $attendee;
       }
     }
 
     // filter out removed attendees
     if (!empty($removed)) {
       $event['attendees'] = array_filter($event['attendees'], function($attendee) use ($removed) {
         return !in_array($attendee['email'], $removed);
       });
     }
   }
 
 
   /****  Resource management functions  ****/
 
   /**
    * Getter for the configured implementation of the resource directory interface
    */
   private function resources_directory()
   {
     if (is_object($this->resources_dir)) {
       return $this->resources_dir;
     }
 
     if ($driver_name = $this->rc->config->get('calendar_resources_driver')) {
       $driver_class = 'resources_driver_' . $driver_name;
 
       require_once($this->home . '/drivers/resources_driver.php');
       require_once($this->home . '/drivers/' . $driver_name . '/' . $driver_class . '.php');
 
       $this->resources_dir = new $driver_class($this);
     }
 
     return $this->resources_dir;
   }
 
   /**
    * Handler for resoruce autocompletion requests
    */
   public function resources_autocomplete()
   {
     $search = rcube_utils::get_input_value('_search', rcube_utils::INPUT_GPC, true);
     $sid    = rcube_utils::get_input_value('_reqid', rcube_utils::INPUT_GPC);
     $maxnum = (int)$this->rc->config->get('autocomplete_max', 15);
     $results = array();
 
     if ($directory = $this->resources_directory()) {
       foreach ($directory->load_resources($search, $maxnum) as $rec) {
         $results[]  = array(
             'name'  => $rec['name'],
             'email' => $rec['email'],
             'type'  => $rec['_type'],
         );
       }
     }
 
     $this->rc->output->command('ksearch_query_results', $results, $search, $sid);
     $this->rc->output->send();
   }
 
   /**
    * Handler for load-requests for resource data
    */
   function resources_list()
   {
     $data = array();
 
     if ($directory = $this->resources_directory()) {
       foreach ($directory->load_resources() as $rec) {
         $data[] = $rec;
       }
     }
 
     $this->rc->output->command('plugin.resource_data', $data);
     $this->rc->output->send();
   }
 
   /**
    * Handler for requests loading resource owner information
    */
   function resources_owner()
   {
     if ($directory = $this->resources_directory()) {
       $id = rcube_utils::get_input_value('_id', rcube_utils::INPUT_GPC);
       $data = $directory->get_resource_owner($id);
     }
 
     $this->rc->output->command('plugin.resource_owner', $data);
     $this->rc->output->send();
   }
 
   /**
    * Deliver event data for a resource's calendar
    */
   function resources_calendar()
   {
     $events = array();
 
     if ($directory = $this->resources_directory()) {
       $events = $directory->get_resource_calendar(
         rcube_utils::get_input_value('_id', rcube_utils::INPUT_GPC),
         rcube_utils::get_input_value('start', rcube_utils::INPUT_GET),
         rcube_utils::get_input_value('end', rcube_utils::INPUT_GET));
     }
 
     echo $this->encode($events);
     exit;
   }
 
 
   /****  Event invitation plugin hooks ****/
 
   /**
    * Handler for calendar/itip-status requests
    */
   function event_itip_status()
   {
     $data = rcube_utils::get_input_value('data', rcube_utils::INPUT_POST, true);
 
     // find local copy of the referenced event
     $this->load_driver();
     $existing = $this->driver->get_event($data, calendar_driver::FILTER_WRITEABLE | calendar_driver::FILTER_PERSONAL);
 
     $itip = $this->load_itip();
     $response = $itip->get_itip_status($data, $existing);
 
     // get a list of writeable calendars to save new events to
     if (!$existing && !$data['nosave'] && $response['action'] == 'rsvp' || $response['action'] == 'import') {
       $calendars = $this->driver->list_calendars(calendar_driver::FILTER_PERSONAL);
       $calendar_select = new html_select(array('name' => 'calendar', 'id' => 'itip-saveto', 'is_escaped' => true));
       $calendar_select->add('--', '');
       $numcals = 0;
       foreach ($calendars as $calendar) {
         if ($calendar['editable']) {
           $calendar_select->add($calendar['name'], $calendar['id']);
           $numcals++;
         }
       }
       if ($numcals <= 1)
         $calendar_select = null;
     }
 
     if ($calendar_select) {
       $default_calendar = $this->get_default_calendar($data['sensitivity']);
       $response['select'] = html::span('folder-select', $this->gettext('saveincalendar') . '&nbsp;' .
         $calendar_select->show($default_calendar['id']));
     }
     else if ($data['nosave']) {
       $response['select'] = html::tag('input', array('type' => 'hidden', 'name' => 'calendar', 'id' => 'itip-saveto', 'value' => ''));
     }
 
     // render small agenda view for the respective day
     if ($data['method'] == 'REQUEST' && !empty($data['date']) && $response['action'] == 'rsvp') {
       $event_start = rcube_utils::anytodatetime($data['date']);
       $day_start = new Datetime(gmdate('Y-m-d 00:00', $data['date']), $this->lib->timezone);
       $day_end = new Datetime(gmdate('Y-m-d 23:59', $data['date']), $this->lib->timezone);
 
       // get events on that day from the user's personal calendars
       $calendars = $this->driver->list_calendars(calendar_driver::FILTER_PERSONAL);
       $events = $this->driver->load_events($day_start->format('U'), $day_end->format('U'), null, array_keys($calendars));
       usort($events, function($a, $b) { return $a['start'] > $b['start'] ? 1 : -1; });
 
       $before = $after = array();
       foreach ($events as $event) {
         // TODO: skip events with free_busy == 'free' ?
         if ($event['uid'] == $data['uid'] || $event['end'] < $day_start || $event['start'] > $day_end)
           continue;
         else if ($event['start'] < $event_start)
           $before[] = $this->mail_agenda_event_row($event);
         else
           $after[] = $this->mail_agenda_event_row($event);
       }
 
       $response['append'] = array(
         'selector' => '.calendar-agenda-preview',
         'replacements' => array(
           '%before%' => !empty($before) ? join("\n", array_slice($before,  -3)) : html::div('event-row no-event', $this->gettext('noearlierevents')),
           '%after%'  => !empty($after)  ? join("\n", array_slice($after, 0, 3)) : html::div('event-row no-event', $this->gettext('nolaterevents')),
         ),
       );
     }
 
     $this->rc->output->command('plugin.update_itip_object_status', $response);
   }
 
   /**
    * Handler for calendar/itip-remove requests
    */
   function event_itip_remove()
   {
     $success  = false;
     $uid      = rcube_utils::get_input_value('uid', rcube_utils::INPUT_POST);
     $instance = rcube_utils::get_input_value('_instance', rcube_utils::INPUT_POST);
     $savemode = rcube_utils::get_input_value('_savemode', rcube_utils::INPUT_POST);
 
     // search for event if only UID is given
     if ($event = $this->driver->get_event(array('uid' => $uid, '_instance' => $instance), calendar_driver::FILTER_WRITEABLE)) {
       $event['_savemode'] = $savemode;
       $success = $this->driver->remove_event($event, true);
     }
 
     if ($success) {
       $this->rc->output->show_message('calendar.successremoval', 'confirmation');
     }
     else {
       $this->rc->output->show_message('calendar.errorsaving', 'error');
     }
   }
 
   /**
    * Handler for URLs that allow an invitee to respond on his invitation mail
    */
   public function itip_attend_response($p)
   {
     if ($p['action'] == 'attend') {
       $this->ui->init();
 
       $this->rc->output->set_env('task', 'calendar');  // override some env vars
       $this->rc->output->set_env('refresh_interval', 0);
       $this->rc->output->set_pagetitle($this->gettext('calendar'));
 
       $itip  = $this->load_itip();
       $token = rcube_utils::get_input_value('_t', rcube_utils::INPUT_GPC);
 
       // read event info stored under the given token
       if ($invitation = $itip->get_invitation($token)) {
         $this->token = $token;
         $this->event = $invitation['event'];
 
         // show message about cancellation
         if ($invitation['cancelled']) {
           $this->invitestatus = html::div('rsvp-status declined', $itip->gettext('eventcancelled'));
         }
         // save submitted RSVP status
         else if (!empty($_POST['rsvp'])) {
           $status = null;
           foreach (array('accepted','tentative','declined') as $method) {
             if ($_POST['rsvp'] == $itip->gettext('itip' . $method)) {
               $status = $method;
               break;
             }
           }
 
           // send itip reply to organizer
           $invitation['event']['comment'] = rcube_utils::get_input_value('_comment', rcube_utils::INPUT_POST);
           if ($status && $itip->update_invitation($invitation, $invitation['attendee'], strtoupper($status))) {
             $this->invitestatus = html::div('rsvp-status ' . strtolower($status), $itip->gettext('youhave'.strtolower($status)));
           }
           else
             $this->rc->output->command('display_message', $this->gettext('errorsaving'), 'error', -1);
 
           // if user is logged in...
           if ($this->rc->user->ID) {
             $this->load_driver();
             $invitation = $itip->get_invitation($token);
 
             // save the event to his/her default calendar if not yet present
             if (!$this->driver->get_event($this->event) && ($calendar = $this->get_default_calendar($invitation['event']['sensitivity']))) {
               $invitation['event']['calendar'] = $calendar['id'];
               if ($this->driver->new_event($invitation['event']))
                 $this->rc->output->command('display_message', $this->gettext(array('name' => 'importedsuccessfully', 'vars' => array('calendar' => $calendar['name']))), 'confirmation');
             }
           }
         }
         
         $this->register_handler('plugin.event_inviteform', array($this, 'itip_event_inviteform'));
         $this->register_handler('plugin.event_invitebox', array($this->ui, 'event_invitebox'));
         
         if (!$this->invitestatus) {
           $this->itip->set_rsvp_actions(array('accepted','tentative','declined'));
           $this->register_handler('plugin.event_rsvp_buttons', array($this->ui, 'event_rsvp_buttons'));
         }
         
         $this->rc->output->set_pagetitle($itip->gettext('itipinvitation') . ' ' . $this->event['title']);
       }
       else
         $this->rc->output->command('display_message', $this->gettext('itipinvalidrequest'), 'error', -1);
       
       $this->rc->output->send('calendar.itipattend');
     }
   }
   
   /**
    *
    */
   public function itip_event_inviteform($attrib)
   {
     $hidden = new html_hiddenfield(array('name' => "_t", 'value' => $this->token));
     return html::tag('form', array('action' => $this->rc->url(array('task' => 'calendar', 'action' => 'attend')), 'method' => 'post', 'noclose' => true) + $attrib) . $hidden->show();
   }
 
   /**
    * 
    */
   private function mail_agenda_event_row($event, $class = '')
   {
     $time = $event['allday'] ? $this->gettext('all-day') :
       $this->rc->format_date($event['start'], $this->rc->config->get('time_format')) . ' - ' .
         $this->rc->format_date($event['end'], $this->rc->config->get('time_format'));
 
     return html::div(rtrim('event-row ' . $class),
       html::span('event-date', $time) .
       html::span('event-title', rcube::Q($event['title']))
     );
   }
   
   /**
    * 
    */
   public function mail_messages_list($p)
   {
     if (in_array('attachment', (array)$p['cols']) && !empty($p['messages'])) {
       foreach ($p['messages'] as $header) {
         $part = new StdClass;
         $part->mimetype = $header->ctype;
         if (libcalendaring::part_is_vcalendar($part)) {
           $header->list_flags['attachmentClass'] = 'ical';
         }
         else if (in_array($header->ctype, array('multipart/alternative', 'multipart/mixed'))) {
           // TODO: fetch bodystructure and search for ical parts. Maybe too expensive?
 
           if (!empty($header->structure) && is_array($header->structure->parts)) {
             foreach ($header->structure->parts as $part) {
               if (libcalendaring::part_is_vcalendar($part) && !empty($part->ctype_parameters['method'])) {
                 $header->list_flags['attachmentClass'] = 'ical';
                 break;
               }
             }
           }
         }
       }
     }
   }
 
   /**
    * Add UI element to copy event invitations or updates to the calendar
    */
   public function mail_messagebody_html($p)
   {
     // load iCalendar functions (if necessary)
     if (!empty($this->lib->ical_parts)) {
       $this->get_ical();
       $this->load_itip();
     }
 
     $html = '';
     $has_events = false;
     $ical_objects = $this->lib->get_mail_ical_objects();
 
     // show a box for every event in the file
     foreach ($ical_objects as $idx => $event) {
       if ($event['_type'] != 'event')  // skip non-event objects (#2928)
         continue;
 
       $has_events = true;
 
       // get prepared inline UI for this event object
       if ($ical_objects->method) {
         $append = '';
 
         // prepare a small agenda preview to be filled with actual event data on async request
         if ($ical_objects->method == 'REQUEST') {
           $append = html::div('calendar-agenda-preview',
             html::tag('h3', 'preview-title', $this->gettext('agenda') . ' ' .
               html::span('date', $this->rc->format_date($event['start'], $this->rc->config->get('date_format')))
             ) . '%before%' . $this->mail_agenda_event_row($event, 'current') . '%after%');
         }
 
         $html .= html::div('calendar-invitebox',
           $this->itip->mail_itip_inline_ui(
             $event,
             $ical_objects->method,
             $ical_objects->mime_id . ':' . $idx,
             'calendar',
             rcube_utils::anytodatetime($ical_objects->message_date),
             $this->rc->url(array('task' => 'calendar')) . '&view=agendaDay&date=' . $event['start']->format('U')
           ) . $append
         );
       }
 
       // limit listing
       if ($idx >= 3)
         break;
     }
 
     // prepend event boxes to message body
     if ($html) {
       $this->ui->init();
       $p['content'] = $html . $p['content'];
       $this->rc->output->add_label('calendar.savingdata','calendar.deleteventconfirm','calendar.declinedeleteconfirm');
     }
 
     // add "Save to calendar" button into attachment menu
     if ($has_events) {
       $this->add_button(array(
         'id'         => 'attachmentsavecal',
         'name'       => 'attachmentsavecal',
         'type'       => 'link',
         'wrapper'    => 'li',
         'command'    => 'attachment-save-calendar',
         'class'      => 'icon calendarlink',
         'classact'   => 'icon calendarlink active',
         'innerclass' => 'icon calendar',
         'label'      => 'calendar.savetocalendar',
         ), 'attachmentmenu');
     }
 
     return $p;
   }
 
 
   /**
    * Handler for POST request to import an event attached to a mail message
    */
   public function mail_import_itip()
   {
     $itip_sending = $this->rc->config->get('calendar_itip_send_option', $this->defaults['calendar_itip_send_option']);
 
     $uid     = rcube_utils::get_input_value('_uid', rcube_utils::INPUT_POST);
     $mbox    = rcube_utils::get_input_value('_mbox', rcube_utils::INPUT_POST);
     $mime_id = rcube_utils::get_input_value('_part', rcube_utils::INPUT_POST);
     $status  = rcube_utils::get_input_value('_status', rcube_utils::INPUT_POST);
     $delete  = intval(rcube_utils::get_input_value('_del', rcube_utils::INPUT_POST));
     $noreply = intval(rcube_utils::get_input_value('_noreply', rcube_utils::INPUT_POST));
     $noreply = $noreply || $status == 'needs-action' || $itip_sending === 0;
     $instance = rcube_utils::get_input_value('_instance', rcube_utils::INPUT_POST);
     $savemode = rcube_utils::get_input_value('_savemode', rcube_utils::INPUT_POST);
 
     $error_msg = $this->gettext('errorimportingevent');
     $success = false;
     $delegate = null;
 
     if ($status == 'delegated') {
       $delegates = rcube_mime::decode_address_list(rcube_utils::get_input_value('_to', rcube_utils::INPUT_POST, true), 1, false);
       $delegate  = reset($delegates);
 
       if (empty($delegate) || empty($delegate['mailto'])) {
         $this->rc->output->command('display_message', $this->gettext('libcalendaring.delegateinvalidaddress'), 'error');
         return;
       }
     }
 
     // successfully parsed events?
     if ($event = $this->lib->mail_get_itip_object($mbox, $uid, $mime_id, 'event')) {
       // forward iTip request to delegatee
       if ($delegate) {
         $rsvpme = intval(rcube_utils::get_input_value('_rsvp', rcube_utils::INPUT_POST));
 
         $itip = $this->load_itip();
         if ($itip->delegate_to($event, $delegate, $rsvpme ? true : false)) {
           $this->rc->output->show_message('calendar.itipsendsuccess', 'confirmation');
         }
         else {
           $this->rc->output->command('display_message', $this->gettext('itipresponseerror'), 'error');
         }
 
         // the delegator is set to non-participant, thus save as non-blocking
         $event['free_busy'] = 'free';
       }
 
       // find writeable calendar to store event
       $cal_id = !empty($_REQUEST['_folder']) ? rcube_utils::get_input_value('_folder', rcube_utils::INPUT_POST) : null;
       $dontsave = ($_REQUEST['_folder'] === '' && $event['_method'] == 'REQUEST');
       $calendars = $this->driver->list_calendars(calendar_driver::FILTER_PERSONAL);
       $calendar = $calendars[$cal_id];
 
       // select default calendar except user explicitly selected 'none'
       if (!$calendar && !$dontsave)
          $calendar = $this->get_default_calendar($event['sensitivity']);
 
       $metadata = array(
         'uid' => $event['uid'],
         '_instance' => $event['_instance'],
         'changed' => is_object($event['changed']) ? $event['changed']->format('U') : 0,
         'sequence' => intval($event['sequence']),
         'fallback' => strtoupper($status),
         'method' => $event['_method'],
         'task' => 'calendar',
       );
 
       // update my attendee status according to submitted method
       if (!empty($status)) {
         $organizer = null;
         $emails = $this->get_user_emails();
         foreach ($event['attendees'] as $i => $attendee) {
           if ($attendee['role'] == 'ORGANIZER') {
             $organizer = $attendee;
           }
           else if ($attendee['email'] && in_array(strtolower($attendee['email']), $emails)) {
             $event['attendees'][$i]['status'] = strtoupper($status);
             if (!in_array($event['attendees'][$i]['status'], array('NEEDS-ACTION','DELEGATED')))
               $event['attendees'][$i]['rsvp'] = false;  // unset RSVP attribute
 
             $metadata['attendee'] = $attendee['email'];
             $metadata['rsvp'] = $attendee['role'] != 'NON-PARTICIPANT';
             $reply_sender = $attendee['email'];
             $event_attendee = $attendee;
           }
         }
 
         // add attendee with this user's default identity if not listed
         if (!$reply_sender) {
           $sender_identity = $this->rc->user->list_emails(true);
           $event['attendees'][] = array(
             'name' => $sender_identity['name'],
             'email' => $sender_identity['email'],
             'role' => 'OPT-PARTICIPANT',
             'status' => strtoupper($status),
           );
           $metadata['attendee'] = $sender_identity['email'];
         }
       }
       
       // save to calendar
       if ($calendar && $calendar['editable']) {
         // check for existing event with the same UID
         $existing = $this->driver->get_event($event, calendar_driver::FILTER_WRITEABLE | calendar_driver::FILTER_PERSONAL);
 
         if ($existing) {
           // forward savemode for correct updates of recurring events
           $existing['_savemode'] = $savemode ?: $event['_savemode'];
 
           // only update attendee status
           if ($event['_method'] == 'REPLY') {
             // try to identify the attendee using the email sender address
             $existing_attendee = -1;
             $existing_attendee_emails = array();
             foreach ($existing['attendees'] as $i => $attendee) {
               $existing_attendee_emails[] = $attendee['email'];
               if ($event['_sender'] && ($attendee['email'] == $event['_sender'] || $attendee['email'] == $event['_sender_utf'])) {
                 $existing_attendee = $i;
               }
             }
             $event_attendee = null;
             $update_attendees = array();
             foreach ($event['attendees'] as $attendee) {
               if ($event['_sender'] && ($attendee['email'] == $event['_sender'] || $attendee['email'] == $event['_sender_utf'])) {
                 $event_attendee = $attendee;
                 $update_attendees[] = $attendee;
                 $metadata['fallback'] = $attendee['status'];
                 $metadata['attendee'] = $attendee['email'];
                 $metadata['rsvp'] = $attendee['rsvp'] || $attendee['role'] != 'NON-PARTICIPANT';
                 if ($attendee['status'] != 'DELEGATED') {
                   break;
                 }
               }
               // also copy delegate attendee
               else if (!empty($attendee['delegated-from']) &&
                        (stripos($attendee['delegated-from'], $event['_sender']) !== false ||
                         stripos($attendee['delegated-from'], $event['_sender_utf']) !== false)) {
                 $update_attendees[] = $attendee;
                 if (!in_array($attendee['email'], $existing_attendee_emails)) {
                   $existing['attendees'][] = $attendee;
                 }
               }
             }
 
             // if delegatee has declined, set delegator's RSVP=True
             if ($event_attendee && $event_attendee['status'] == 'DECLINED' && $event_attendee['delegated-from']) {
               foreach ($existing['attendees'] as $i => $attendee) {
                 if ($attendee['email'] == $event_attendee['delegated-from']) {
                   $existing['attendees'][$i]['rsvp'] = true;
                   break;
                 }
               }
             }
 
             // found matching attendee entry in both existing and new events
             if ($existing_attendee >= 0 && $event_attendee) {
               $existing['attendees'][$existing_attendee] = $event_attendee;
               $success = $this->driver->update_attendees($existing, $update_attendees);
             }
             // update the entire attendees block
             else if (($event['sequence'] >= $existing['sequence'] || $event['changed'] >= $existing['changed']) && $event_attendee) {
               $existing['attendees'][] = $event_attendee;
               $success = $this->driver->update_attendees($existing, $update_attendees);
             }
             else {
               $error_msg = $this->gettext('newerversionexists');
             }
           }
           // delete the event when declined (#1670)
           else if ($status == 'declined' && $delete) {
              $deleted = $this->driver->remove_event($existing, true);
              $success = true;
           }
           // import the (newer) event
           else if ($event['sequence'] >= $existing['sequence'] || $event['changed'] >= $existing['changed']) {
             $event['id'] = $existing['id'];
             $event['calendar'] = $existing['calendar'];
 
             // preserve my participant status for regular updates
             if (empty($status)) {
               $emails = $this->get_user_emails();
               foreach ($event['attendees'] as $i => $attendee) {
                 if ($attendee['email'] && in_array(strtolower($attendee['email']), $emails)) {
                   foreach ($existing['attendees'] as $j => $_attendee) {
                     if ($attendee['email'] == $_attendee['email']) {
                       $event['attendees'][$i] = $existing['attendees'][$j];
                       break;
                     }
                   }
                 }
               }
             }
 
             // set status=CANCELLED on CANCEL messages
             if ($event['_method'] == 'CANCEL')
               $event['status'] = 'CANCELLED';
             // show me as free when declined (#1670)
             if ($status == 'declined' || $event['status'] == 'CANCELLED' || $event_attendee['role'] == 'NON-PARTICIPANT')
               $event['free_busy'] = 'free';
 
             $success = $this->driver->edit_event($event);
           }
           else if (!empty($status)) {
             $existing['attendees'] = $event['attendees'];
             if ($status == 'declined' || $event_attendee['role'] == 'NON-PARTICIPANT')  // show me as free when declined (#1670)
               $existing['free_busy'] = 'free';
             $success = $this->driver->edit_event($existing);
           }
           else
             $error_msg = $this->gettext('newerversionexists');
         }
         else if (!$existing && ($status != 'declined' || $this->rc->config->get('kolab_invitation_calendars'))) {
           if ($status == 'declined' || $event['status'] == 'CANCELLED' || $event_attendee['role'] == 'NON-PARTICIPANT') {
             $event['free_busy'] = 'free';
           }
 
           // if the RSVP reply only refers to a single instance:
           // store unmodified master event with current instance as exception
           if (!empty($instance) && !empty($savemode) && $savemode != 'all') {
             $master = $this->lib->mail_get_itip_object($mbox, $uid, $mime_id, 'event');
             if ($master['recurrence'] && !$master['_instance']) {
               // compute recurring events until this instance's date
               if ($recurrence_date = rcube_utils::anytodatetime($instance, $master['start']->getTimezone())) {
                 $recurrence_date->setTime(23,59,59);
 
                 foreach ($this->driver->get_recurring_events($master, $master['start'], $recurrence_date) as $recurring) {
                   if ($recurring['_instance'] == $instance) {
                     // copy attendees block with my partstat to exception
                     $recurring['attendees'] = $event['attendees'];
                     $master['recurrence']['EXCEPTIONS'][] = $recurring;
                     $event = $recurring;  // set reference for iTip reply
                     break;
                   }
                 }
 
                 $master['calendar'] = $event['calendar'] = $calendar['id'];
                 $success = $this->driver->new_event($master);
               }
               else {
                 $master = null;
               }
             }
             else {
               $master = null;
             }
           }
 
           // save to the selected/default calendar
           if (!$master) {
             $event['calendar'] = $calendar['id'];
             $success = $this->driver->new_event($event);
           }
         }
         else if ($status == 'declined')
           $error_msg = null;
       }
       else if ($status == 'declined' || $dontsave)
         $error_msg = null;
       else
         $error_msg = $this->gettext('nowritecalendarfound');
     }
 
     if ($success) {
       $message = $event['_method'] == 'REPLY' ? 'attendeupdateesuccess' : ($deleted ? 'successremoval' : ($existing ? 'updatedsuccessfully' : 'importedsuccessfully'));
       $this->rc->output->command('display_message', $this->gettext(array('name' => $message, 'vars' => array('calendar' => $calendar['name']))), 'confirmation');
     }
 
     if ($success || $dontsave) {
       $metadata['calendar'] = $event['calendar'];
       $metadata['nosave'] = $dontsave;
       $metadata['rsvp'] = intval($metadata['rsvp']);
       $metadata['after_action'] = $this->rc->config->get('calendar_itip_after_action', $this->defaults['calendar_itip_after_action']);
       $this->rc->output->command('plugin.itip_message_processed', $metadata);
       $error_msg = null;
     }
     else if ($error_msg) {
       $this->rc->output->command('display_message', $error_msg, 'error');
     }
 
     // send iTip reply
     if ($event['_method'] == 'REQUEST' && $organizer && !$noreply && !in_array(strtolower($organizer['email']), $emails) && !$error_msg) {
       $event['comment'] = rcube_utils::get_input_value('_comment', rcube_utils::INPUT_POST);
       $itip = $this->load_itip();
       $itip->set_sender_email($reply_sender);
       if ($itip->send_itip_message($event, 'REPLY', $organizer, 'itipsubject' . $status, 'itipmailbody' . $status))
         $this->rc->output->command('display_message', $this->gettext(array('name' => 'sentresponseto', 'vars' => array('mailto' => $organizer['name'] ? $organizer['name'] : $organizer['email']))), 'confirmation');
       else
         $this->rc->output->command('display_message', $this->gettext('itipresponseerror'), 'error');
     }
 
     $this->rc->output->send();
   }
 
 
   /**
    * Handler for calendar/itip-remove requests
    */
   function mail_itip_decline_reply()
   {
     $uid     = rcube_utils::get_input_value('_uid', rcube_utils::INPUT_POST);
     $mbox    = rcube_utils::get_input_value('_mbox', rcube_utils::INPUT_POST);
     $mime_id = rcube_utils::get_input_value('_part', rcube_utils::INPUT_POST);
 
     if (($event = $this->lib->mail_get_itip_object($mbox, $uid, $mime_id, 'event')) && $event['_method'] == 'REPLY') {
       $event['comment'] = rcube_utils::get_input_value('_comment', rcube_utils::INPUT_POST);
 
       foreach ($event['attendees'] as $_attendee) {
         if ($_attendee['role'] != 'ORGANIZER') {
           $attendee = $_attendee;
           break;
         }
       }
 
       $itip = $this->load_itip();
       if ($itip->send_itip_message($event, 'CANCEL', $attendee, 'itipsubjectcancel', 'itipmailbodycancel'))
         $this->rc->output->command('display_message', $this->gettext(array('name' => 'sentresponseto', 'vars' => array('mailto' => $attendee['name'] ? $attendee['name'] : $attendee['email']))), 'confirmation');
       else
         $this->rc->output->command('display_message', $this->gettext('itipresponseerror'), 'error');
     }
     else {
       $this->rc->output->command('display_message', $this->gettext('itipresponseerror'), 'error');
     }
   }
 
   /**
    * Handler for calendar/itip-delegate requests
    */
   function mail_itip_delegate()
   {
     // forward request to mail_import_itip() with the right status
     $_POST['_status'] = $_REQUEST['_status'] = 'delegated';
     $this->mail_import_itip();
   }
 
   /**
    * Import the full payload from a mail message attachment
    */
   public function mail_import_attachment()
   {
     $uid     = rcube_utils::get_input_value('_uid', rcube_utils::INPUT_POST);
     $mbox    = rcube_utils::get_input_value('_mbox', rcube_utils::INPUT_POST);
     $mime_id = rcube_utils::get_input_value('_part', rcube_utils::INPUT_POST);
     $charset = RCUBE_CHARSET;
 
     // establish imap connection
     $imap = $this->rc->get_storage();
     $imap->set_mailbox($mbox);
 
     if ($uid && $mime_id) {
       $part = $imap->get_message_part($uid, $mime_id);
       if ($part->ctype_parameters['charset'])
         $charset = $part->ctype_parameters['charset'];
 //      $headers = $imap->get_message_headers($uid);
 
       if ($part) {
         $events = $this->get_ical()->import($part, $charset);
       }
     }
 
     $success = $existing = 0;
     if (!empty($events)) {
       // find writeable calendar to store event
       $cal_id = !empty($_REQUEST['_calendar']) ? rcube_utils::get_input_value('_calendar', rcube_utils::INPUT_POST) : null;
       $calendars = $this->driver->list_calendars(calendar_driver::FILTER_PERSONAL);
 
       foreach ($events as $event) {
         // save to calendar
         $calendar = $calendars[$cal_id] ?: $this->get_default_calendar($event['sensitivity']);
         if ($calendar && $calendar['editable'] && $event['_type'] == 'event') {
           $event['calendar'] = $calendar['id'];
 
           if (!$this->driver->get_event($event['uid'], calendar_driver::FILTER_WRITEABLE)) {
             $success += (bool)$this->driver->new_event($event);
           }
           else {
             $existing++;
           }
         }
       }
     }
 
     if ($success) {
       $this->rc->output->command('display_message', $this->gettext(array(
         'name' => 'importsuccess',
         'vars' => array('nr' => $success),
       )), 'confirmation');
     }
     else if ($existing) {
       $this->rc->output->command('display_message', $this->gettext('importwarningexists'), 'warning');
     }
     else {
       $this->rc->output->command('display_message', $this->gettext('errorimportingevent'), 'error');
     }
   }
 
   /**
    * Read email message and return contents for a new event based on that message
    */
   public function mail_message2event()
   {
     $uid   = rcube_utils::get_input_value('_uid', rcube_utils::INPUT_POST);
     $mbox  = rcube_utils::get_input_value('_mbox', rcube_utils::INPUT_POST);
     $event = array();
 
     // establish imap connection
     $imap = $this->rc->get_storage();
     $imap->set_mailbox($mbox);
     $message = new rcube_message($uid);
 
     if ($message->headers) {
       $event['title'] = trim($message->subject);
       $event['description'] = trim($message->first_text_part());
 
       $this->load_driver();
 
       // add a reference to the email message
       if ($msgref = $this->driver->get_message_reference($message->headers, $mbox)) {
         $event['links'] = array($msgref);
       }
       // copy mail attachments to event
       else if ($message->attachments) {
         $eventid = 'cal-';
         if (!is_array($_SESSION[self::SESSION_KEY]) || $_SESSION[self::SESSION_KEY]['id'] != $eventid) {
           $_SESSION[self::SESSION_KEY] = array();
           $_SESSION[self::SESSION_KEY]['id'] = $eventid;
           $_SESSION[self::SESSION_KEY]['attachments'] = array();
         }
 
         foreach ((array)$message->attachments as $part) {
           $attachment = array(
             'data' => $imap->get_message_part($uid, $part->mime_id, $part),
             'size' => $part->size,
             'name' => $part->filename,
             'mimetype' => $part->mimetype,
             'group' => $eventid,
           );
 
           $attachment = $this->rc->plugins->exec_hook('attachment_save', $attachment);
 
           if ($attachment['status'] && !$attachment['abort']) {
             $id = $attachment['id'];
             $attachment['classname'] = rcube_utils::file2class($attachment['mimetype'], $attachment['name']);
 
             // store new attachment in session
             unset($attachment['status'], $attachment['abort'], $attachment['data']);
             $_SESSION[self::SESSION_KEY]['attachments'][$id] = $attachment;
 
             $attachment['id'] = 'rcmfile' . $attachment['id'];  // add prefix to consider it 'new'
             $event['attachments'][] = $attachment;
           }
         }
       }
       
       $this->rc->output->command('plugin.mail2event_dialog', $event);
     }
     else {
       $this->rc->output->command('display_message', $this->gettext('messageopenerror'), 'error');
     }
     
     $this->rc->output->send();
   }
 
   /**
    * Handler for the 'message_compose' plugin hook. This will check for
    * a compose parameter 'calendar_event' and create an attachment with the
    * referenced event in iCal format
    */
   public function mail_message_compose($args)
   {
     // set the submitted event ID as attachment
     if (!empty($args['param']['calendar_event'])) {
       $this->load_driver();
 
       list($cal, $id) = explode(':', $args['param']['calendar_event'], 2);
       if ($event = $this->driver->get_event(array('id' => $id, 'calendar' => $cal))) {
         $filename = asciiwords($event['title']);
         if (empty($filename))
           $filename = 'event';
 
         // save ics to a temp file and register as attachment
         $tmp_path = tempnam($this->rc->config->get('temp_dir'), 'rcmAttmntCal');
         file_put_contents($tmp_path, $this->get_ical()->export(array($event), '', false, array($this->driver, 'get_attachment_body')));
 
         $args['attachments'][] = array('path' => $tmp_path, 'name' => $filename . '.ics', 'mimetype' => 'text/calendar');
         $args['param']['subject'] = $event['title'];
       }
     }
 
     return $args;
   }
 
 
   /**
    * Get a list of email addresses of the current user (from login and identities)
    */
   public function get_user_emails()
   {
     return $this->lib->get_user_emails();
   }
 
 
   /**
    * Build an absolute URL with the given parameters
    */
   public function get_url($param = array())
   {
     $param += array('task' => 'calendar');
     return $this->rc->url($param, true, true);
   }
 
 
   public function ical_feed_hash($source)
   {
     return base64_encode($this->rc->user->get_username() . ':' . $source);
   }
 
   /**
    * Handler for user_delete plugin hook
    */
   public function user_delete($args)
   {
      // delete itipinvitations entries related to this user
      $db = $this->rc->get_dbh();
      $table_itipinvitations = $db->table_name('itipinvitations', true);
      $db->query("DELETE FROM $table_itipinvitations WHERE `user_id` = ?", $args['user']->ID);
 
      $this->load_driver();
      return $this->driver->user_delete($args);
   }
 
   /**
    * Magic getter for public access to protected members
    */
   public function __get($name)
   {
     switch ($name) {
       case 'ical':
         return $this->get_ical();
 
       case 'itip':
         return $this->load_itip();
 
       case 'driver':
         $this->load_driver();
         return $this->driver;
     }
 
     return null;
   }
 
 }
diff --git a/plugins/calendar/drivers/kolab/kolab_driver.php b/plugins/calendar/drivers/kolab/kolab_driver.php
index 1c52fbab..b4c2978c 100644
--- a/plugins/calendar/drivers/kolab/kolab_driver.php
+++ b/plugins/calendar/drivers/kolab/kolab_driver.php
@@ -1,2525 +1,2525 @@
 <?php
 
 /**
  * Kolab driver for the Calendar plugin
  *
  * @version @package_version@
  * @author Thomas Bruederli <bruederli@kolabsys.com>
  * @author Aleksander Machniak <machniak@kolabsys.com>
  *
  * Copyright (C) 2012-2015, Kolab Systems AG <contact@kolabsys.com>
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
  * published by the Free Software Foundation, either version 3 of the
  * License, or (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  * GNU Affero General Public License for more details.
  *
  * You should have received a copy of the GNU Affero General Public License
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 
 class kolab_driver extends calendar_driver
 {
   const INVITATIONS_CALENDAR_PENDING  = '--invitation--pending';
   const INVITATIONS_CALENDAR_DECLINED = '--invitation--declined';
 
   // features this backend supports
   public $alarms = true;
   public $attendees = true;
   public $freebusy = true;
   public $attachments = true;
   public $undelete = true;
   public $alarm_types = array('DISPLAY','AUDIO');
   public $categoriesimmutable = true;
 
   private $rc;
   private $cal;
   private $calendars;
   private $has_writeable = false;
   private $freebusy_trigger = false;
   private $bonnie_api = false;
 
   /**
    * Default constructor
    */
   public function __construct($cal)
   {
     $cal->require_plugin('libkolab');
 
     // load helper classes *after* libkolab has been loaded (#3248)
     require_once(dirname(__FILE__) . '/kolab_calendar.php');
     require_once(dirname(__FILE__) . '/kolab_user_calendar.php');
     require_once(dirname(__FILE__) . '/kolab_invitation_calendar.php');
 
     $this->cal = $cal;
     $this->rc = $cal->rc;
     $this->_read_calendars();
     
     $this->cal->register_action('push-freebusy', array($this, 'push_freebusy'));
     $this->cal->register_action('calendar-acl', array($this, 'calendar_acl'));
     
     $this->freebusy_trigger = $this->rc->config->get('calendar_freebusy_trigger', false);
 
     if (kolab_storage::$version == '2.0') {
         $this->alarm_types = array('DISPLAY');
         $this->alarm_absolute = false;
     }
 
     // get configuration for the Bonnie API
     $this->bonnie_api = libkolab::get_bonnie_api();
 
     // calendar uses fully encoded identifiers
     kolab_storage::$encode_ids = true;
   }
 
 
   /**
    * Read available calendars from server
    */
   private function _read_calendars()
   {
     // already read sources
     if (isset($this->calendars))
       return $this->calendars;
 
     // get all folders that have "event" type, sorted by namespace/name
     $folders = kolab_storage::sort_folders(kolab_storage::get_folders('event') + kolab_storage::get_user_folders('event', true));
     $this->calendars = array();
 
     foreach ($folders as $folder) {
       if ($folder instanceof kolab_storage_folder_user) {
         $calendar = new kolab_user_calendar($folder->name, $this->cal);
         $calendar->subscriptions = count($folder->children) > 0;
       }
       else {
         $calendar = new kolab_calendar($folder->name, $this->cal);
       }
 
       if ($calendar->ready) {
         $this->calendars[$calendar->id] = $calendar;
         if ($calendar->editable)
           $this->has_writeable = true;
       }
     }
 
     return $this->calendars;
   }
 
   /**
    * Get a list of available calendars from this source
    *
    * @param integer $filter Bitmask defining filter criterias
    * @param object $tree   Reference to hierarchical folder tree object
    *
    * @return array List of calendars
    */
   public function list_calendars($filter = 0, &$tree = null)
   {
     // attempt to create a default calendar for this user
     if (!$this->has_writeable) {
       if ($this->create_calendar(array('name' => 'Calendar', 'color' => 'cc0000'))) {
          unset($this->calendars);
         $this->_read_calendars();
       }
     }
 
     $delim = $this->rc->get_storage()->get_hierarchy_delimiter();
     $folders = $this->filter_calendars($filter);
     $calendars = array();
 
     // include virtual folders for a full folder tree
     if (!is_null($tree))
       $folders = kolab_storage::folder_hierarchy($folders, $tree);
 
     foreach ($folders as $id => $cal) {
       $fullname = $cal->get_name();
       $listname = $cal->get_foldername();
       $imap_path = explode($delim, $cal->name);
 
       // find parent
       do {
         array_pop($imap_path);
         $parent_id = kolab_storage::folder_id(join($delim, $imap_path));
       }
       while (count($imap_path) > 1 && !$this->calendars[$parent_id]);
 
       // restore "real" parent ID
       if ($parent_id && !$this->calendars[$parent_id]) {
           $parent_id = kolab_storage::folder_id($cal->get_parent());
       }
 
       // turn a kolab_storage_folder object into a kolab_calendar
       if ($cal instanceof kolab_storage_folder) {
           $cal = new kolab_calendar($cal->name, $this->cal);
           $this->calendars[$cal->id] = $cal;
       }
 
       // special handling for user or virtual folders
       if ($cal instanceof kolab_storage_folder_user) {
         $calendars[$cal->id] = array(
           'id' => $cal->id,
           'name' => kolab_storage::object_name($fullname),
           'listname' => $listname,
           'editname' => $cal->get_foldername(),
           'color'    => $cal->get_color(),
           'active'   => $cal->is_active(),
           'title'    => $cal->get_owner(),
           'owner'    => $cal->get_owner(),
           'history'  => false,
           'virtual'  => false,
           'editable' => false,
           'group'     => 'other',
           'class'     => 'user',
           'removable' => true,
         );
       }
       else if ($cal->virtual) {
         $calendars[$cal->id] = array(
           'id' => $cal->id,
           'name' => $fullname,
           'listname' => $listname,
           'editname' => $cal->get_foldername(),
           'virtual'  => true,
           'editable' => false,
           'group'     => $cal->get_namespace(),
           'class'     => 'folder',
         );
       }
       else {
         $calendars[$cal->id] = array(
           'id'       => $cal->id,
           'name'     => $fullname,
           'listname' => $listname,
           'editname' => $cal->get_foldername(),
           'title'    => $cal->get_title(),
           'color'    => $cal->get_color(),
           'editable' => $cal->editable,
           'rights'    => $cal->rights,
           'showalarms' => $cal->alarms,
           'history'  => !empty($this->bonnie_api),
           'group'    => $cal->get_namespace(),
           'default'  => $cal->default,
           'active'   => $cal->is_active(),
           'owner'    => $cal->get_owner(),
           'children' => true,  // TODO: determine if that folder indeed has child folders
           'parent'   => $parent_id,
           'subtype'  => $cal->subtype,
           'caldavurl' => $cal->get_caldav_url(),
           'removable' => !$cal->default,
         );
       }
 
       if ($cal->subscriptions) {
         $calendars[$cal->id]['subscribed'] = $cal->is_subscribed();
       }
     }
 
     // list virtual calendars showing invitations
     if ($this->rc->config->get('kolab_invitation_calendars')) {
       foreach (array(self::INVITATIONS_CALENDAR_PENDING, self::INVITATIONS_CALENDAR_DECLINED) as $id) {
         $cal = new kolab_invitation_calendar($id, $this->cal);
         $this->calendars[$cal->id] = $cal;
         if (!($filter & self::FILTER_ACTIVE) || $cal->is_active()) {
           $calendars[$id] = array(
             'id'       => $cal->id,
             'name'     => $cal->get_name(),
             'listname' => $cal->get_name(),
             'editname' => $cal->get_foldername(),
             'title'    => $cal->get_title(),
             'color'    => $cal->get_color(),
             'editable' => $cal->editable,
             'rights'    => $cal->rights,
             'showalarms' => $cal->alarms,
             'history'  => !empty($this->bonnie_api),
             'group'    => 'x-invitations',
             'default'  => false,
             'active'   => $cal->is_active(),
             'owner'    => $cal->get_owner(),
             'children' => false,
           );
 
           if ($id == self::INVITATIONS_CALENDAR_PENDING) {
             $calendars[$id]['counts'] = true;
           }
 
           if (is_object($tree)) {
             $tree->children[] = $cal;
           }
         }
       }
     }
 
     // append the virtual birthdays calendar
     if ($this->rc->config->get('calendar_contact_birthdays', false)) {
       $id = self::BIRTHDAY_CALENDAR_ID;
       $prefs = $this->rc->config->get('kolab_calendars', array());  // read local prefs
       if (!($filter & self::FILTER_ACTIVE) || $prefs[$id]['active']) {
         $calendars[$id] = array(
           'id'         => $id,
           'name'       => $this->cal->gettext('birthdays'),
           'listname'   => $this->cal->gettext('birthdays'),
           'color'      => $prefs[$id]['color'] ?: '87CEFA',
           'active'     => (bool)$prefs[$id]['active'],
           'showalarms' => (bool)$this->rc->config->get('calendar_birthdays_alarm_type'),
           'group'      => 'x-birthdays',
           'editable'  => false,
           'default'    => false,
           'children'   => false,
           'history'    => false,
         );
       }
     }
 
     return $calendars;
   }
 
   /**
    * Get list of calendars according to specified filters
    *
    * @param integer Bitmask defining restrictions. See FILTER_* constants for possible values.
    *
    * @return array List of calendars
    */
   protected function filter_calendars($filter)
   {
     $calendars = array();
 
     $plugin = $this->rc->plugins->exec_hook('calendar_list_filter', array(
       'list'      => $this->calendars,
       'calendars' => $calendars,
       'filter'    => $filter,
       'editable'  => ($filter & self::FILTER_WRITEABLE),
       'insert'    => ($filter & self::FILTER_INSERTABLE),
       'active'    => ($filter & self::FILTER_ACTIVE),
       'personal'  => ($filter & self::FILTER_PERSONAL)
     ));
 
     if ($plugin['abort']) {
       return $plugin['calendars'];
     }
 
     foreach ($this->calendars as $cal) {
       if (!$cal->ready) {
         continue;
       }
       if (($filter & self::FILTER_WRITEABLE) && !$cal->editable) {
         continue;
       }
       if (($filter & self::FILTER_INSERTABLE) && !$cal->insert) {
         continue;
       }
       if (($filter & self::FILTER_ACTIVE) && !$cal->is_active()) {
         continue;
       }
       if (($filter & self::FILTER_PRIVATE) && $cal->subtype != 'private') {
         continue;
       }
       if (($filter & self::FILTER_CONFIDENTIAL) && $cal->subtype != 'confidential') {
         continue;
       }
       if (($filter & self::FILTER_PERSONAL) && $cal->get_namespace() != 'personal') {
         continue;
       }
       $calendars[$cal->id] = $cal;
     }
 
     return $calendars;
   }
 
 
   /**
    * Get the kolab_calendar instance for the given calendar ID
    *
    * @param string Calendar identifier (encoded imap folder name)
    * @return object kolab_calendar Object nor null if calendar doesn't exist
    */
   public function get_calendar($id)
   {
     // create calendar object if necesary
     if (!$this->calendars[$id] && in_array($id, array(self::INVITATIONS_CALENDAR_PENDING, self::INVITATIONS_CALENDAR_DECLINED))) {
       $this->calendars[$id] = new kolab_invitation_calendar($id, $this->cal);
     }
     else if (!$this->calendars[$id] && $id !== self::BIRTHDAY_CALENDAR_ID) {
       $calendar = kolab_calendar::factory($id, $this->cal);
       if ($calendar->ready)
         $this->calendars[$calendar->id] = $calendar;
     }
 
     return $this->calendars[$id];
   }
 
   /**
    * Create a new calendar assigned to the current user
    *
    * @param array Hash array with calendar properties
    *    name: Calendar name
    *   color: The color of the calendar
    * @return mixed ID of the calendar on success, False on error
    */
   public function create_calendar($prop)
   {
     $prop['type'] = 'event';
     $prop['active'] = true;
     $prop['subscribed'] = true;
     $folder = kolab_storage::folder_update($prop);
 
     if ($folder === false) {
       $this->last_error = $this->cal->gettext(kolab_storage::$last_error);
       return false;
     }
 
     // create ID
     $id = kolab_storage::folder_id($folder);
 
     // save color in user prefs (temp. solution)
     $prefs['kolab_calendars'] = $this->rc->config->get('kolab_calendars', array());
 
     if (isset($prop['color']))
       $prefs['kolab_calendars'][$id]['color'] = $prop['color'];
     if (isset($prop['showalarms']))
       $prefs['kolab_calendars'][$id]['showalarms'] = $prop['showalarms'] ? true : false;
 
     if ($prefs['kolab_calendars'][$id])
       $this->rc->user->save_prefs($prefs);
 
     return $id;
   }
 
 
   /**
    * Update properties of an existing calendar
    *
    * @see calendar_driver::edit_calendar()
    */
   public function edit_calendar($prop)
   {
     if ($prop['id'] && ($cal = $this->get_calendar($prop['id']))) {
       $id = $cal->update($prop);
     }
     else {
       $id = $prop['id'];
     }
 
     // fallback to local prefs
     $prefs['kolab_calendars'] = $this->rc->config->get('kolab_calendars', array());
     unset($prefs['kolab_calendars'][$prop['id']]['color'], $prefs['kolab_calendars'][$prop['id']]['showalarms']);
 
     if (isset($prop['color']))
       $prefs['kolab_calendars'][$id]['color'] = $prop['color'];
 
     if (isset($prop['showalarms']) && $id == self::BIRTHDAY_CALENDAR_ID)
       $prefs['calendar_birthdays_alarm_type'] = $prop['showalarms'] ? $this->alarm_types[0] : '';
     else if (isset($prop['showalarms']))
       $prefs['kolab_calendars'][$id]['showalarms'] = $prop['showalarms'] ? true : false;
 
     if (!empty($prefs['kolab_calendars'][$id]))
       $this->rc->user->save_prefs($prefs);
 
     return true;
   }
 
 
   /**
    * Set active/subscribed state of a calendar
    *
    * @see calendar_driver::subscribe_calendar()
    */
   public function subscribe_calendar($prop)
   {
     if ($prop['id'] && ($cal = $this->get_calendar($prop['id'])) && is_object($cal->storage)) {
       $ret = false;
       if (isset($prop['permanent']))
         $ret |= $cal->storage->subscribe(intval($prop['permanent']));
       if (isset($prop['active']))
         $ret |= $cal->storage->activate(intval($prop['active']));
 
       // apply to child folders, too
       if ($prop['recursive']) {
         foreach ((array)kolab_storage::list_folders($cal->storage->name, '*', 'event') as $subfolder) {
           if (isset($prop['permanent']))
             ($prop['permanent'] ? kolab_storage::folder_subscribe($subfolder) : kolab_storage::folder_unsubscribe($subfolder));
           if (isset($prop['active']))
             ($prop['active'] ? kolab_storage::folder_activate($subfolder) : kolab_storage::folder_deactivate($subfolder));
         }
       }
       return $ret;
     }
     else {
       // save state in local prefs
       $prefs['kolab_calendars'] = $this->rc->config->get('kolab_calendars', array());
       $prefs['kolab_calendars'][$prop['id']]['active'] = (bool)$prop['active'];
       $this->rc->user->save_prefs($prefs);
       return true;
     }
 
     return false;
   }
 
 
   /**
    * Delete the given calendar with all its contents
    *
    * @see calendar_driver::delete_calendar()
    */
   public function delete_calendar($prop)
   {
     if ($prop['id'] && ($cal = $this->get_calendar($prop['id']))) {
       $folder = $cal->get_realname();
       // TODO: unsubscribe if no admin rights
       if (kolab_storage::folder_delete($folder)) {
         // remove color in user prefs (temp. solution)
         $prefs['kolab_calendars'] = $this->rc->config->get('kolab_calendars', array());
         unset($prefs['kolab_calendars'][$prop['id']]);
 
         $this->rc->user->save_prefs($prefs);
         return true;
       }
       else
         $this->last_error = kolab_storage::$last_error;
     }
 
     return false;
   }
 
 
   /**
    * Search for shared or otherwise not listed calendars the user has access
    *
    * @param string Search string
    * @param string Section/source to search
    * @return array List of calendars
    */
   public function search_calendars($query, $source)
   {
     if (!kolab_storage::setup())
       return array();
 
     $this->calendars = array();
     $this->search_more_results = false;
 
     // find unsubscribed IMAP folders that have "event" type
     if ($source == 'folders') {
       foreach ((array)kolab_storage::search_folders('event', $query, array('other')) as $folder) {
         $calendar = new kolab_calendar($folder->name, $this->cal);
         $this->calendars[$calendar->id] = $calendar;
       }
     }
     // find other user's virtual calendars
     else if ($source == 'users') {
       $limit = $this->rc->config->get('autocomplete_max', 15) * 2;  // we have slightly more space, so display twice the number
       foreach (kolab_storage::search_users($query, 0, array(), $limit, $count) as $user) {
         $calendar = new kolab_user_calendar($user, $this->cal);
         $this->calendars[$calendar->id] = $calendar;
 
         // search for calendar folders shared by this user
         foreach (kolab_storage::list_user_folders($user, 'event', false) as $foldername) {
           $cal = new kolab_calendar($foldername, $this->cal);
           $this->calendars[$cal->id] = $cal;
           $calendar->subscriptions = true;
         }
       }
 
       if ($count > $limit) {
         $this->search_more_results = true;
       }
     }
 
     // don't list the birthday calendar
     $this->rc->config->set('calendar_contact_birthdays', false);
     $this->rc->config->set('kolab_invitation_calendars', false);
 
     return $this->list_calendars();
   }
 
 
   /**
    * Fetch a single event
    *
    * @see calendar_driver::get_event()
    * @return array Hash array with event properties, false if not found
    */
   public function get_event($event, $scope = 0, $full = false)
   {
     if (is_array($event)) {
       $id = $event['id'] ?: $event['uid'];
       $cal = $event['calendar'];
 
       // we're looking for a recurring instance: expand the ID to our internal convention for recurring instances
       if (!$event['id'] && $event['_instance']) {
         $id .= '-' . $event['_instance'];
       }
     }
     else {
       $id = $event;
     }
 
     if ($cal) {
       if ($storage = $this->get_calendar($cal)) {
         $result = $storage->get_event($id);
         return self::to_rcube_event($result);
       }
       // get event from the address books birthday calendar
       else if ($cal == self::BIRTHDAY_CALENDAR_ID) {
         return $this->get_birthday_event($id);
       }
     }
     // iterate over all calendar folders and search for the event ID
     else {
       foreach ($this->filter_calendars($scope) as $calendar) {
         if ($result = $calendar->get_event($id)) {
           return self::to_rcube_event($result);
         }
       }
     }
 
     return false;
   }
 
   /**
    * Add a single event to the database
    *
    * @see calendar_driver::new_event()
    */
   public function new_event($event)
   {
     if (!$this->validate($event))
       return false;
 
     $event = self::from_rcube_event($event);
 
     $cid = $event['calendar'] ? $event['calendar'] : reset(array_keys($this->calendars));
     if ($storage = $this->get_calendar($cid)) {
       // if this is a recurrence instance, append as exception to an already existing object for this UID
       if (!empty($event['recurrence_date']) && ($master = $storage->get_event($event['uid']))) {
         self::add_exception($master, $event);
         $success = $storage->update_event($master);
       }
       else {
         $success = $storage->insert_event($event);
       }
 
       if ($success && $this->freebusy_trigger) {
         $this->rc->output->command('plugin.ping_url', array('action' => 'calendar/push-freebusy', 'source' => $storage->id));
         $this->freebusy_trigger = false; // disable after first execution (#2355)
       }
       
       return $success;
     }
 
     return false;
   }
 
   /**
    * Update an event entry with the given data
    *
    * @see calendar_driver::new_event()
    * @return boolean True on success, False on error
    */
   public function edit_event($event)
   {
      if (!($storage = $this->get_calendar($event['calendar'])))
        return false;
 
     return $this->update_event(self::from_rcube_event($event, $storage->get_event($event['id'])));
   }
 
   /**
    * Extended event editing with possible changes to the argument
    *
    * @param array  Hash array with event properties
    * @param string New participant status
    * @param array  List of hash arrays with updated attendees
    * @return boolean True on success, False on error
    */
   public function edit_rsvp(&$event, $status, $attendees)
   {
     $update_event = $event;
 
     // apply changes to master (and all exceptions)
     if ($event['_savemode'] == 'all' && $event['recurrence_id']) {
       if ($storage = $this->get_calendar($event['calendar'])) {
         $update_event = $storage->get_event($event['recurrence_id']);
         $update_event['_savemode'] = $event['_savemode'];
         $update_event['id'] = $update_event['uid'];
         unset($update_event['recurrence_id']);
         calendar::merge_attendee_data($update_event, $attendees);
       }
     }
 
     if ($ret = $this->update_attendees($update_event, $attendees)) {
       // replace with master event (for iTip reply)
       $event = self::to_rcube_event($update_event);
 
       // re-assign to the according (virtual) calendar
       if ($this->rc->config->get('kolab_invitation_calendars')) {
         if (strtoupper($status) == 'DECLINED')
           $event['calendar'] = self::INVITATIONS_CALENDAR_DECLINED;
         else if (strtoupper($status) == 'NEEDS-ACTION')
           $event['calendar'] = self::INVITATIONS_CALENDAR_PENDING;
         else if ($event['_folder_id'])
           $event['calendar'] = $event['_folder_id'];
       }
     }
 
     return $ret;
   }
 
   /**
    * Update the participant status for the given attendees
    *
    * @see calendar_driver::update_attendees()
    */
   public function update_attendees(&$event, $attendees)
   {
     // for this-and-future updates, merge the updated attendees onto all exceptions in range
     if (($event['_savemode'] == 'future' && $event['recurrence_id']) || (!empty($event['recurrence']) && !$event['recurrence_id'])) {
       if (!($storage = $this->get_calendar($event['calendar'])))
         return false;
 
       // load master event
       $master = $event['recurrence_id'] ? $storage->get_event($event['recurrence_id']) : $event;
 
       // apply attendee update to each existing exception
       if ($master['recurrence'] && !empty($master['recurrence']['EXCEPTIONS'])) {
         $saved = false;
         foreach ($master['recurrence']['EXCEPTIONS'] as $i => $exception) {
           // merge the new event properties onto future exceptions
           if ($exception['_instance'] >= strval($event['_instance'])) {
             calendar::merge_attendee_data($master['recurrence']['EXCEPTIONS'][$i], $attendees);
           }
           // update a specific instance
           if ($exception['_instance'] == $event['_instance'] && $exception['thisandfuture']) {
             $saved = true;
           }
         }
 
         // add the given event as new exception
         if (!$saved && $event['id'] != $master['id']) {
           $event['thisandfuture'] = true;
           $master['recurrence']['EXCEPTIONS'][] = $event;
         }
 
         // set link to top-level exceptions
         $master['exceptions'] = &$master['recurrence']['EXCEPTIONS'];
 
         return $this->update_event($master);
       }
     }
 
     // just update the given event (instance)
     return $this->update_event($event);
   }
 
   /**
    * Move a single event
    *
    * @see calendar_driver::move_event()
    * @return boolean True on success, False on error
    */
   public function move_event($event)
   {
     if (($storage = $this->get_calendar($event['calendar'])) && ($ev = $storage->get_event($event['id']))) {
       unset($ev['sequence']);
       self::clear_attandee_noreply($ev);
       return $this->update_event($event + $ev);
     }
 
     return false;
   }
 
   /**
    * Resize a single event
    *
    * @see calendar_driver::resize_event()
    * @return boolean True on success, False on error
    */
   public function resize_event($event)
   {
     if (($storage = $this->get_calendar($event['calendar'])) && ($ev = $storage->get_event($event['id']))) {
       unset($ev['sequence']);
       self::clear_attandee_noreply($ev);
       return $this->update_event($event + $ev);
     }
 
     return false;
   }
 
   /**
    * Remove a single event
    *
    * @param array   Hash array with event properties:
    *      id: Event identifier
    * @param boolean Remove record(s) irreversible (mark as deleted otherwise)
    *
    * @return boolean True on success, False on error
    */
   public function remove_event($event, $force = true)
   {
     $ret = true;
     $success = false;
     $savemode = $event['_savemode'];
     $decline  = $event['_decline'];
 
     if (($storage = $this->get_calendar($event['calendar'])) && ($event = $storage->get_event($event['id']))) {
       $event['_savemode'] = $savemode;
       $savemode = 'all';
       $master = $event;
 
       $this->rc->session->remove('calendar_restore_event_data');
 
       // read master if deleting a recurring event
       if ($event['recurrence'] || $event['recurrence_id'] || $event['isexception']) {
         $master = $storage->get_event($event['uid']);
         $savemode = $event['_savemode'] ?: ($event['_instance'] || $event['isexception'] ? 'current' : 'all');
 
         // force 'current' mode for single occurrences stored as exception
         if (!$event['recurrence'] && !$event['recurrence_id'] && $event['isexception'])
           $savemode = 'current';
       }
 
       // removing an exception instance
       if (($event['recurrence_id'] || $event['isexception']) && is_array($master['exceptions'])) {
         foreach ($master['exceptions'] as $i => $exception) {
           if ($exception['_instance'] == $event['_instance']) {
             unset($master['exceptions'][$i]);
             // set event date back to the actual occurrence
             if ($exception['recurrence_date'])
               $event['start'] = $exception['recurrence_date'];
           }
         }
 
         if (is_array($master['recurrence'])) {
           $master['recurrence']['EXCEPTIONS'] = &$master['exceptions'];
         }
       }
 
       switch ($savemode) {
         case 'current':
           $_SESSION['calendar_restore_event_data'] = $master;
 
           // removing the first instance => just move to next occurence
           if ($master['recurrence'] && $event['_instance'] == libcalendaring::recurrence_instance_identifier($master)) {
             $recurring = reset($storage->get_recurring_events($event, $event['start'], null, $event['id'].'-1'));
 
             // no future instances found: delete the master event (bug #1677)
             if (!$recurring['start']) {
               $success = $storage->delete_event($master, $force);
               break;
             }
 
             $master['start'] = $recurring['start'];
             $master['end'] = $recurring['end'];
             if ($master['recurrence']['COUNT'])
               $master['recurrence']['COUNT']--;
           }
           // remove the matching RDATE entry
           else if ($master['recurrence']['RDATE']) {
             foreach ($master['recurrence']['RDATE'] as $j => $rdate) {
               if ($rdate->format('Ymd') == $event['start']->format('Ymd')) {
                 unset($master['recurrence']['RDATE'][$j]);
                 break;
               }
             }
           }
           else {  // add exception to master event
             $master['recurrence']['EXDATE'][] = $event['start'];
           }
           $success = $storage->update_event($master);
           break;
 
         case 'future':
           $master['_instance'] = libcalendaring::recurrence_instance_identifier($master);
           if ($master['_instance'] != $event['_instance']) {
             $_SESSION['calendar_restore_event_data'] = $master;
             
             // set until-date on master event
             $master['recurrence']['UNTIL'] = clone $event['start'];
             $master['recurrence']['UNTIL']->sub(new DateInterval('P1D'));
             unset($master['recurrence']['COUNT']);
 
             // if all future instances are deleted, remove recurrence rule entirely (bug #1677)
             if ($master['recurrence']['UNTIL']->format('Ymd') == $master['start']->format('Ymd')) {
               $master['recurrence'] = array();
             }
             // remove matching RDATE entries
             else if ($master['recurrence']['RDATE']) {
               foreach ($master['recurrence']['RDATE'] as $j => $rdate) {
                 if ($rdate->format('Ymd') == $event['start']->format('Ymd')) {
                   $master['recurrence']['RDATE'] = array_slice($master['recurrence']['RDATE'], 0, $j);
                   break;
                 }
               }
             }
 
             $success = $storage->update_event($master);
             $ret = $master['uid'];
             break;
           }
 
         default:  // 'all' is default
           // removing the master event with loose exceptions (not recurring though)
           if (!empty($event['recurrence_date']) && empty($master['recurrence']) && !empty($master['exceptions'])) {
             // make the first exception the new master
             $newmaster = array_shift($master['exceptions']);
             $newmaster['exceptions'] = $master['exceptions'];
             $newmaster['_attachments'] = $master['_attachments'];
             $newmaster['_mailbox'] = $master['_mailbox'];
             $newmaster['_msguid'] = $master['_msguid'];
 
             $success = $storage->update_event($newmaster);
           }
           else if ($decline && $this->rc->config->get('kolab_invitation_calendars')) {
             // don't delete but set PARTSTAT=DECLINED
             if ($this->cal->lib->set_partstat($master, 'DECLINED')) {
               $success = $storage->update_event($master);
             }
           }
 
           if (!$success)
             $success = $storage->delete_event($master, $force);
           break;
       }
     }
     
     if ($success && $this->freebusy_trigger)
       $this->rc->output->command('plugin.ping_url', array('action' => 'calendar/push-freebusy', 'source' => $storage->id));
 
     return $success ? $ret : false;
   }
 
   /**
    * Restore a single deleted event
    *
    * @param array Hash array with event properties:
    *      id: Event identifier
    * @return boolean True on success, False on error
    */
   public function restore_event($event)
   {
     if ($storage = $this->get_calendar($event['calendar'])) {
       if (!empty($_SESSION['calendar_restore_event_data']))
         $success = $storage->update_event($_SESSION['calendar_restore_event_data']);
       else
         $success = $storage->restore_event($event);
       
       if ($success && $this->freebusy_trigger)
         $this->rc->output->command('plugin.ping_url', array('action' => 'calendar/push-freebusy', 'source' => $storage->id));
       
       return $success;
     }
 
     return false;
   }
 
   /**
    * Wrapper to update an event object depending on the given savemode
    */
   private function update_event($event)
   {
     if (!($storage = $this->get_calendar($event['calendar'])))
       return false;
 
     // move event to another folder/calendar
     if ($event['_fromcalendar'] && $event['_fromcalendar'] != $event['calendar']) {
       if (!($fromcalendar = $this->get_calendar($event['_fromcalendar'])))
         return false;
 
       $old = $fromcalendar->get_event($event['id']);
 
       if ($event['_savemode'] != 'new') {
         if (!$fromcalendar->storage->move($old['uid'], $storage->storage)) {
           return false;
         }
 
         $fromcalendar = $storage;
       }
     }
     else
       $fromcalendar = $storage;
 
     $success = false;
     $savemode = 'all';
     $attachments = array();
     $old = $master = $storage->get_event($event['id']);
 
     if (!$old || !$old['start']) {
       rcube::raise_error(array(
         'code' => 600, 'type' => 'php',
         'file' => __FILE__, 'line' => __LINE__,
         'message' => "Failed to load event object to update: id=" . $event['id']),
         true, false);
       return false;
     }
 
     // modify a recurring event, check submitted savemode to do the right things
     if ($old['recurrence'] || $old['recurrence_id'] || $old['isexception']) {
       $master = $storage->get_event($old['uid']);
       $savemode = $event['_savemode'] ?: ($old['recurrence_id'] || $old['isexception'] ? 'current' : 'all');
 
       // this-and-future on the first instance equals to 'all'
       if ($savemode == 'future' && $master['start'] && $old['_instance'] == libcalendaring::recurrence_instance_identifier($master))
         $savemode = 'all';
       // force 'current' mode for single occurrences stored as exception
       else if (!$old['recurrence'] && !$old['recurrence_id'] && $old['isexception'])
         $savemode = 'current';
     }
 
     // check if update affects scheduling and update attendee status accordingly
     $reschedule = $this->check_scheduling($event, $old, true);
 
     // keep saved exceptions (not submitted by the client)
     if ($old['recurrence']['EXDATE'] && !isset($event['recurrence']['EXDATE']))
       $event['recurrence']['EXDATE'] = $old['recurrence']['EXDATE'];
     if (isset($event['recurrence']['EXCEPTIONS']))
       $with_exceptions = true;  // exceptions already provided (e.g. from iCal import)
     else if ($old['recurrence']['EXCEPTIONS'])
       $event['recurrence']['EXCEPTIONS'] = $old['recurrence']['EXCEPTIONS'];
     else if ($old['exceptions'])
       $event['exceptions'] = $old['exceptions'];
 
     // remove some internal properties which should not be saved
     unset($event['_savemode'], $event['_fromcalendar'], $event['_identity'], $event['_owner'],
         $event['_notify'], $event['_method'], $event['_sender'], $event['_sender_utf'], $event['_size']);
 
     switch ($savemode) {
       case 'new':
         // save submitted data as new (non-recurring) event
         $event['recurrence'] = array();
         $event['_copyfrom'] = $master['_msguid'];
         $event['_mailbox'] = $master['_mailbox'];
         $event['uid'] = $this->cal->generate_uid();
         unset($event['recurrence_id'], $event['recurrence_date'], $event['_instance'], $event['id']);
 
         // copy attachment metadata to new event
         $event = self::from_rcube_event($event, $master);
 
         self::clear_attandee_noreply($event);
         if ($success = $storage->insert_event($event))
           $success = $event['uid'];
         break;
 
       case 'future':
         // create a new recurring event
         $event['_copyfrom'] = $master['_msguid'];
         $event['_mailbox'] = $master['_mailbox'];
         $event['uid'] = $this->cal->generate_uid();
         unset($event['recurrence_id'], $event['recurrence_date'], $event['_instance'], $event['id']);
 
         // copy attachment metadata to new event
         $event = self::from_rcube_event($event, $master);
   
         // remove recurrence exceptions on re-scheduling
         if ($reschedule) {
           unset($event['recurrence']['EXCEPTIONS'], $event['exceptions'], $master['recurrence']['EXDATE']);
         }
         else if (is_array($event['recurrence']['EXCEPTIONS'])) {
           // only keep relevant exceptions
           $event['recurrence']['EXCEPTIONS'] = array_filter($event['recurrence']['EXCEPTIONS'], function($exception) use ($event) {
             return $exception['start'] > $event['start'];
           });
           if (is_array($event['recurrence']['EXDATE'])) {
             $event['recurrence']['EXDATE'] = array_filter($event['recurrence']['EXDATE'], function($exdate) use ($event) {
               return $exdate > $event['start'];
             });
           }
           // set link to top-level exceptions
           $event['exceptions'] = &$event['recurrence']['EXCEPTIONS'];
         }
 
         // compute remaining occurrences
         if ($event['recurrence']['COUNT']) {
           if (!$old['_count'])
             $old['_count'] = $this->get_recurrence_count($master, $old['start']);
           $event['recurrence']['COUNT'] -= intval($old['_count']);
         }
 
         // remove fixed weekday when date changed
         if ($old['start']->format('Y-m-d') != $event['start']->format('Y-m-d')) {
           if (strlen($event['recurrence']['BYDAY']) == 2)
             unset($event['recurrence']['BYDAY']);
           if ($old['recurrence']['BYMONTH'] == $old['start']->format('n'))
             unset($event['recurrence']['BYMONTH']);
         }
 
         // set until-date on master event
         $master['recurrence']['UNTIL'] = clone $old['start'];
         $master['recurrence']['UNTIL']->sub(new DateInterval('P1D'));
         unset($master['recurrence']['COUNT']);
 
         // remove all exceptions after $event['start']
         if (is_array($master['recurrence']['EXCEPTIONS'])) {
           $master['recurrence']['EXCEPTIONS'] = array_filter($master['recurrence']['EXCEPTIONS'], function($exception) use ($event) {
             return $exception['start'] < $event['start'];
           });
           // set link to top-level exceptions
           $master['exceptions'] = &$master['recurrence']['EXCEPTIONS'];
         }
         if (is_array($master['recurrence']['EXDATE'])) {
           $master['recurrence']['EXDATE'] = array_filter($master['recurrence']['EXDATE'], function($exdate) use ($event) {
             return $exdate < $event['start'];
           });
         }
 
         // save new event
         if ($success = $storage->insert_event($event)) {
           $success = $event['uid'];
 
           // update master event (no rescheduling!)
           self::clear_attandee_noreply($master);
           $storage->update_event($master);
         }
         break;
 
       case 'current':
         // recurring instances shall not store recurrence rules and attachments
         $event['recurrence'] = array();
         $event['thisandfuture'] = $savemode == 'future';
         unset($event['attachments'], $event['id']);
 
         // increment sequence of this instance if scheduling is affected
         if ($reschedule) {
           $event['sequence'] = max($old['sequence'], $master['sequence']) + 1;
         }
         else if (!isset($event['sequence'])) {
           $event['sequence'] = $old['sequence'] ?: $master['sequence'];
         }
 
         // save properties to a recurrence exception instance
         if ($old['_instance'] && is_array($master['recurrence']['EXCEPTIONS'])) {
           if ($this->update_recurrence_exceptions($master, $event, $old, $savemode)) {
             $success = $storage->update_event($master, $old['id']);
             break;
           }
         }
 
         $add_exception = true;
 
         // adjust matching RDATE entry if dates changed
         if (is_array($master['recurrence']['RDATE']) && ($old_date = $old['start']->format('Ymd')) != $event['start']->format('Ymd')) {
           foreach ($master['recurrence']['RDATE'] as $j => $rdate) {
             if ($rdate->format('Ymd') == $old_date) {
               $master['recurrence']['RDATE'][$j] = $event['start'];
               sort($master['recurrence']['RDATE']);
               $add_exception = false;
               break;
             }
           }
         }
 
         // save as new exception to master event
         if ($add_exception) {
           self::add_exception($master, $event, $old);
         }
 
         $success = $storage->update_event($master);
         break;
 
       default:  // 'all' is default
         $event['id'] = $master['uid'];
         $event['uid'] = $master['uid'];
 
         // use start date from master but try to be smart on time or duration changes
         $old_start_date = $old['start']->format('Y-m-d');
         $old_start_time = $old['allday'] ? '' : $old['start']->format('H:i');
         $old_duration = $old['end']->format('U') - $old['start']->format('U');
         
         $new_start_date = $event['start']->format('Y-m-d');
         $new_start_time = $event['allday'] ? '' : $event['start']->format('H:i');
         $new_duration = $event['end']->format('U') - $event['start']->format('U');
         
         $diff = $old_start_date != $new_start_date || $old_start_time != $new_start_time || $old_duration != $new_duration;
         $date_shift = $old['start']->diff($event['start']);
         
         // shifted or resized
         if ($diff && ($old_start_date == $new_start_date || $old_duration == $new_duration)) {
           $event['start'] = $master['start']->add($date_shift);
           $event['end'] = clone $event['start'];
           $event['end']->add(new DateInterval('PT'.$new_duration.'S'));
           
           // remove fixed weekday, will be re-set to the new weekday in kolab_calendar::update_event()
           if ($old_start_date != $new_start_date) {
             if (strlen($event['recurrence']['BYDAY']) == 2)
               unset($event['recurrence']['BYDAY']);
             if ($old['recurrence']['BYMONTH'] == $old['start']->format('n'))
               unset($event['recurrence']['BYMONTH']);
           }
         }
         // dates did not change, use the ones from master
         else if ($new_start_date . $new_start_time == $old_start_date . $old_start_time) {
           $event['start'] = $master['start'];
           $event['end'] = $master['end'];
         }
 
         // when saving an instance in 'all' mode, copy recurrence exceptions over
         if ($old['recurrence_id']) {
           $event['recurrence']['EXCEPTIONS'] = $master['recurrence']['EXCEPTIONS'];
         }
         else if ($master['_instance']) {
           $event['_instance'] = $master['_instance'];
           $event['recurrence_date'] = $master['recurrence_date'];
         }
 
         // TODO: forward changes to exceptions (which do not yet have differing values stored)
         if (is_array($event['recurrence']) && is_array($event['recurrence']['EXCEPTIONS']) && !$with_exceptions) {
           // determine added and removed attendees
           $old_attendees = $current_attendees = $added_attendees = array();
           foreach ((array)$old['attendees'] as $attendee) {
             $old_attendees[] = $attendee['email'];
           }
           foreach ((array)$event['attendees'] as $attendee) {
             $current_attendees[] = $attendee['email'];
             if (!in_array($attendee['email'], $old_attendees)) {
               $added_attendees[] = $attendee;
             }
           }
           $removed_attendees = array_diff($old_attendees, $current_attendees);
 
           foreach ($event['recurrence']['EXCEPTIONS'] as $i => $exception) {
             calendar::merge_attendee_data($event['recurrence']['EXCEPTIONS'][$i], $added_attendees, $removed_attendees);
           }
 
           // adjust recurrence-id when start changed and therefore the entire recurrence chain changes
           if ($old_start_date != $new_start_date || $old_start_time != $new_start_time) {
             $recurrence_id_format = libcalendaring::recurrence_id_format($event);
             foreach ($event['recurrence']['EXCEPTIONS'] as $i => $exception) {
               $recurrence_id = is_a($exception['recurrence_date'], 'DateTime') ? $exception['recurrence_date'] :
                   rcube_utils::anytodatetime($exception['_instance'], $old['start']->getTimezone());
               if (is_a($recurrence_id, 'DateTime')) {
                 $recurrence_id->add($date_shift);
                 $event['recurrence']['EXCEPTIONS'][$i]['recurrence_date'] = $recurrence_id;
                 $event['recurrence']['EXCEPTIONS'][$i]['_instance'] = $recurrence_id->format($recurrence_id_format);
               }
             }
           }
 
           // set link to top-level exceptions
           $event['exceptions'] = &$event['recurrence']['EXCEPTIONS'];
         }
 
         // unset _dateonly flags in (cached) date objects
         unset($event['start']->_dateonly, $event['end']->_dateonly);
 
         $success = $storage->update_event($event) ? $event['id'] : false;  // return master UID
         break;
     }
 
     if ($success && $this->freebusy_trigger)
       $this->rc->output->command('plugin.ping_url', array('action' => 'calendar/push-freebusy', 'source' => $storage->id));
     
     return $success;
   }
 
   /**
    * Determine whether the current change affects scheduling and reset attendee status accordingly
    */
   public function check_scheduling(&$event, $old, $update = true)
   {
     // skip this check when importing iCal/iTip events
     if (isset($event['sequence']) || !empty($event['_method'])) {
       return false;
     }
 
     // iterate through the list of properties considered 'significant' for scheduling
     $kolab_event = $old['_formatobj'] ?: new kolab_format_event();
     $reschedule = $kolab_event->check_rescheduling($event, $old);
 
     // reset all attendee status to needs-action (#4360)
     if ($update && $reschedule && is_array($event['attendees'])) {
       $is_organizer = false;
       $emails = $this->cal->get_user_emails();
       $attendees = $event['attendees'];
       foreach ($attendees as $i => $attendee) {
         if ($attendee['role'] == 'ORGANIZER' && $attendee['email'] && in_array(strtolower($attendee['email']), $emails)) {
           $is_organizer = true;
         }
         else if ($attendee['role'] != 'ORGANIZER' && $attendee['role'] != 'NON-PARTICIPANT' && $attendee['status'] != 'DELEGATED') {
           $attendees[$i]['status'] = 'NEEDS-ACTION';
           $attendees[$i]['rsvp'] = true;
         }
       }
 
       // update attendees only if I'm the organizer
       if ($is_organizer || ($event['organizer'] && in_array(strtolower($event['organizer']['email']), $emails))) {
         $event['attendees'] = $attendees;
       }
     }
 
     return $reschedule;
   }
 
   /**
    * Apply the given changes to already existing exceptions
    */
   protected function update_recurrence_exceptions(&$master, $event, $old, $savemode)
   {
     $saved = false;
     $existing = null;
 
     // determine added and removed attendees
     $added_attendees = $removed_attendees = array();
     if ($savemode == 'future') {
       $old_attendees = $current_attendees = array();
       foreach ((array)$old['attendees'] as $attendee) {
         $old_attendees[] = $attendee['email'];
       }
       foreach ((array)$event['attendees'] as $attendee) {
         $current_attendees[] = $attendee['email'];
         if (!in_array($attendee['email'], $old_attendees)) {
           $added_attendees[] = $attendee;
         }
       }
       $removed_attendees = array_diff($old_attendees, $current_attendees);
     }
 
     foreach ($master['recurrence']['EXCEPTIONS'] as $i => $exception) {
       // update a specific instance
       if ($exception['_instance'] == $old['_instance']) {
         $existing = $i;
 
         // check savemode against existing exception mode.
         // if matches, we can update this existing exception
         if ((bool)$exception['thisandfuture'] === ($savemode == 'future')) {
           $event['_instance'] = $old['_instance'];
           $event['thisandfuture'] = $old['thisandfuture'];
           $event['recurrence_date'] = $old['recurrence_date'];
           $master['recurrence']['EXCEPTIONS'][$i] = $event;
           $saved = true;
         }
       }
       // merge the new event properties onto future exceptions
       if ($savemode == 'future' && $exception['_instance'] >= $old['_instance']) {
         unset($event['thisandfuture']);
         self::merge_exception_data($master['recurrence']['EXCEPTIONS'][$i], $event, array('attendees'));
 
         if (!empty($added_attendees) || !empty($removed_attendees)) {
           calendar::merge_attendee_data($master['recurrence']['EXCEPTIONS'][$i], $added_attendees, $removed_attendees);
         }
       }
     }
 /*
     // we could not update the existing exception due to savemode mismatch...
     if (!$saved && $existing !== null && $master['recurrence']['EXCEPTIONS'][$existing]['thisandfuture']) {
       // ... try to move the existing this-and-future exception to the next occurrence
       foreach ($this->get_recurring_events($master, $existing['start']) as $candidate) {
         // our old this-and-future exception is obsolete
         if ($candidate['thisandfuture']) {
           unset($master['recurrence']['EXCEPTIONS'][$existing]);
           $saved = true;
           break;
         }
         // this occurrence doesn't yet have an exception
         else if (!$candidate['isexception']) {
           $event['_instance'] = $candidate['_instance'];
           $event['recurrence_date'] = $candidate['recurrence_date'];
           $master['recurrence']['EXCEPTIONS'][$i] = $event;
           $saved = true;
           break;
         }
       }
     }
 */
 
     // set link to top-level exceptions
     $master['exceptions'] = &$master['recurrence']['EXCEPTIONS'];
 
     // returning false here will add a new exception
     return $saved;
   }
 
   /**
    * Add or update the given event as an exception to $master
    */
   public static function add_exception(&$master, $event, $old = null)
   {
     if ($old) {
       $event['_instance'] = $old['_instance'];
       if (!$event['recurrence_date'])
         $event['recurrence_date'] = $old['recurrence_date'] ?: $old['start'];
     }
     else if (!$event['recurrence_date']) {
       $event['recurrence_date'] = $event['start'];
     }
 
     if (!$event['_instance'] && is_a($event['recurrence_date'], 'DateTime')) {
       $event['_instance'] = libcalendaring::recurrence_instance_identifier($event);
     }
 
     if (!is_array($master['exceptions']) && is_array($master['recurrence']['EXCEPTIONS'])) {
       $master['exceptions'] = &$master['recurrence']['EXCEPTIONS'];
     }
 
     $existing = false;
     foreach ((array)$master['exceptions'] as $i => $exception) {
       if ($exception['_instance'] == $event['_instance']) {
         $master['exceptions'][$i] = $event;
         $existing = true;
       }
     }
 
     if (!$existing) {
       $master['exceptions'][] = $event;
     }
 
     return true;
   }
 
   /**
    * Remove the noreply flags from attendees
    */
   public static function clear_attandee_noreply(&$event)
   {
     foreach ((array)$event['attendees'] as $i => $attendee) {
       unset($event['attendees'][$i]['noreply']);
     }
   }
 
 
   /**
    * Merge certain properties from the overlay event to the base event object
    *
    * @param array The event object to be altered
    * @param array The overlay event object to be merged over $event
    * @param array List of properties not allowed to be overwritten
    */
   public static function merge_exception_data(&$event, $overlay, $blacklist = null)
   {
     $forbidden = array('id','uid','recurrence','recurrence_date','thisandfuture','organizer','_attachments');
 
     if (is_array($blacklist))
       $forbidden = array_merge($forbidden, $blacklist);
 
     // compute date offset from the exception
     if ($overlay['start'] instanceof DateTime && $overlay['recurrence_date'] instanceof DateTime) {
       $date_offset = $overlay['recurrence_date']->diff($overlay['start']);
     }
 
     foreach ($overlay as $prop => $value) {
       if ($prop == 'start' || $prop == 'end') {
         if (is_object($event[$prop]) && $event[$prop] instanceof DateTime) {
           // set date value if overlay is an exception of the current instance
           if (substr($overlay['_instance'], 0, 8) == substr($event['_instance'], 0, 8)) {
             $event[$prop]->setDate(intval($value->format('Y')), intval($value->format('n')), intval($value->format('j')));
           }
           // apply date offset
           else if ($date_offset) {
             $event[$prop]->add($date_offset);
           }
           // adjust time of the recurring event instance
           $event[$prop]->setTime($value->format('G'), intval($value->format('i')), intval($value->format('s')));
         }
       }
       else if ($prop == 'thisandfuture' && $overlay['_instance'] == $event['_instance']) {
         $event[$prop] = $value;
       }
       else if ($prop[0] != '_' && !in_array($prop, $forbidden))
         $event[$prop] = $value;
     }
   }
 
   /**
    * Get events from source.
    *
    * @param  integer Event's new start (unix timestamp)
    * @param  integer Event's new end (unix timestamp)
    * @param  string  Search query (optional)
    * @param  mixed   List of calendar IDs to load events from (either as array or comma-separated string)
    * @param  boolean Include virtual events (optional)
    * @param  integer Only list events modified since this time (unix timestamp)
    * @return array A list of event records
    */
   public function load_events($start, $end, $search = null, $calendars = null, $virtual = 1, $modifiedsince = null)
   {
     if ($calendars && is_string($calendars))
       $calendars = explode(',', $calendars);
     else if (!$calendars)
       $calendars = array_keys($this->calendars);
 
     $query = array();
     if ($modifiedsince)
       $query[] = array('changed', '>=', $modifiedsince);
 
     $events = $categories = array();
     foreach ($calendars as $cid) {
       if ($storage = $this->get_calendar($cid)) {
         $events = array_merge($events, $storage->list_events($start, $end, $search, $virtual, $query));
         $categories += $storage->categories;
       }
     }
 
     // add events from the address books birthday calendar
     if (in_array(self::BIRTHDAY_CALENDAR_ID, $calendars)) {
       $events = array_merge($events, $this->load_birthday_events($start, $end, $search, $modifiedsince));
     }
 
     // add new categories to user prefs
     $old_categories = $this->rc->config->get('calendar_categories', $this->default_categories);
     if ($newcats = array_udiff(array_keys($categories), array_keys($old_categories), function($a, $b){ return strcasecmp($a, $b); })) {
       foreach ($newcats as $category)
         $old_categories[$category] = '';  // no color set yet
       $this->rc->user->save_prefs(array('calendar_categories' => $old_categories));
     }
 
     array_walk($events, 'kolab_driver::to_rcube_event');
     return $events;
   }
 
   /**
    * Get number of events in the given calendar
    *
    * @param  mixed   List of calendar IDs to count events (either as array or comma-separated string)
    * @param  integer Date range start (unix timestamp)
    * @param  integer Date range end (unix timestamp)
    * @return array   Hash array with counts grouped by calendar ID
    */
   public function count_events($calendars, $start, $end = null)
   {
       $counts = array();
 
       if ($calendars && is_string($calendars))
         $calendars = explode(',', $calendars);
       else if (!$calendars)
         $calendars = array_keys($this->calendars);
 
       foreach ($calendars as $cid) {
         if ($storage = $this->get_calendar($cid)) {
             $counts[$cid] = $storage->count_events($start, $end);
         }
       }
 
       return $counts;
   }
 
   /**
    * Get a list of pending alarms to be displayed to the user
    *
    * @see calendar_driver::pending_alarms()
    */
   public function pending_alarms($time, $calendars = null)
   {
     $interval = 300;
     $time -= $time % 60;
     
     $slot = $time;
     $slot -= $slot % $interval;
     
     $last = $time - max(60, $this->rc->config->get('refresh_interval', 0));
     $last -= $last % $interval;
     
     // only check for alerts once in 5 minutes
     if ($last == $slot)
       return array();
     
     if ($calendars && is_string($calendars))
       $calendars = explode(',', $calendars);
     
     $time = $slot + $interval;
     
     $candidates = array();
     $query = array(array('tags', '=', 'x-has-alarms'));
     foreach ($this->calendars as $cid => $calendar) {
       // skip calendars with alarms disabled
       if (!$calendar->alarms || ($calendars && !in_array($cid, $calendars)))
         continue;
 
       foreach ($calendar->list_events($time, $time + 86400 * 365, null, 1, $query) as $e) {
         // add to list if alarm is set
         $alarm = libcalendaring::get_next_alarm($e);
         if ($alarm && $alarm['time'] && $alarm['time'] >= $last && in_array($alarm['action'], $this->alarm_types)) {
           $id = $alarm['id'];  // use alarm-id as primary identifier
           $candidates[$id] = array(
             'id'       => $id,
             'title'    => $e['title'],
             'location' => $e['location'],
             'start'    => $e['start'],
             'end'      => $e['end'],
             'notifyat' => $alarm['time'],
             'action'   => $alarm['action'],
           );
         }
       }
     }
 
     // get alarm information stored in local database
     if (!empty($candidates)) {
       $alarm_ids = array_map(array($this->rc->db, 'quote'), array_keys($candidates));
       $result = $this->rc->db->query("SELECT *"
         . " FROM " . $this->rc->db->table_name('kolab_alarms', true)
         . " WHERE `alarm_id` IN (" . join(',', $alarm_ids) . ")"
           . " AND `user_id` = ?",
         $this->rc->user->ID
       );
 
       while ($result && ($e = $this->rc->db->fetch_assoc($result))) {
         $dbdata[$e['alarm_id']] = $e;
       }
     }
     
     $alarms = array();
     foreach ($candidates as $id => $alarm) {
       // skip dismissed alarms
       if ($dbdata[$id]['dismissed'])
         continue;
       
       // snooze function may have shifted alarm time
       $notifyat = $dbdata[$id]['notifyat'] ? strtotime($dbdata[$id]['notifyat']) : $alarm['notifyat'];
       if ($notifyat <= $time)
         $alarms[] = $alarm;
     }
     
     return $alarms;
   }
 
   /**
    * Feedback after showing/sending an alarm notification
    *
    * @see calendar_driver::dismiss_alarm()
    */
   public function dismiss_alarm($alarm_id, $snooze = 0)
   {
     $alarms_table = $this->rc->db->table_name('kolab_alarms', true);
     // delete old alarm entry
     $this->rc->db->query("DELETE FROM $alarms_table"
       . " WHERE `alarm_id` = ? AND `user_id` = ?",
       $alarm_id,
       $this->rc->user->ID
     );
 
     // set new notifyat time or unset if not snoozed
     $notifyat = $snooze > 0 ? date('Y-m-d H:i:s', time() + $snooze) : null;
 
     $query = $this->rc->db->query("INSERT INTO $alarms_table"
       . " (`alarm_id`, `user_id`, `dismissed`, `notifyat`)"
       . " VALUES (?, ?, ?, ?)",
       $alarm_id,
       $this->rc->user->ID,
       $snooze > 0 ? 0 : 1,
       $notifyat
     );
 
     return $this->rc->db->affected_rows($query);
   }
 
   /**
    * List attachments from the given event
    */
   public function list_attachments($event)
   {
     if (!($storage = $this->get_calendar($event['calendar'])))
       return false;
 
     $event = $storage->get_event($event['id']);
 
     return $event['attachments'];
   }
 
   /**
    * Get attachment properties
    */
   public function get_attachment($id, $event)
   {
     if (!($storage = $this->get_calendar($event['calendar'])))
       return false;
 
     // get old revision of event
     if ($event['rev']) {
       $event = $this->get_event_revison($event, $event['rev'], true);
     }
     else {
       $event = $storage->get_event($event['id']);
     }
 
     if ($event && !empty($event['_attachments'])) {
       foreach ($event['_attachments'] as $att) {
         if ($att['id'] == $id) {
           return $att;
         }
       }
     }
 
     return null;
   }
 
   /**
    * Get attachment body
    * @see calendar_driver::get_attachment_body()
    */
   public function get_attachment_body($id, $event)
   {
     if (!($cal = $this->get_calendar($event['calendar'])))
       return false;
 
     // get old revision of event
     if ($event['rev']) {
       if (empty($this->bonnie_api)) {
         return false;
       }
 
       $cid = substr($id, 4);
 
       // call Bonnie API and get the raw mime message
       list($uid, $mailbox, $msguid) = $this->_resolve_event_identity($event);
       if ($msg_raw = $this->bonnie_api->rawdata('event', $uid, $event['rev'], $mailbox, $msguid)) {
         // parse the message and find the part with the matching content-id
         $message = rcube_mime::parse_message($msg_raw);
         foreach ((array)$message->parts as $part) {
           if ($part->headers['content-id'] && trim($part->headers['content-id'], '<>') == $cid) {
             return $part->body;
           }
         }
       }
 
       return false;
     }
 
     return $cal->get_attachment_body($id, $event);
   }
 
   /**
    * Build a struct representing the given message reference
    *
    * @see calendar_driver::get_message_reference()
    */
   public function get_message_reference($uri_or_headers, $folder = null)
   {
       if (is_object($uri_or_headers)) {
           $uri_or_headers = kolab_storage_config::get_message_uri($uri_or_headers, $folder);
       }
 
       if (is_string($uri_or_headers)) {
           return kolab_storage_config::get_message_reference($uri_or_headers, 'event');
       }
 
       return false;
   }
 
   /**
    * List availabale categories
    * The default implementation reads them from config/user prefs
    */
   public function list_categories()
   {
     // FIXME: complete list with categories saved in config objects (KEP:12)
     return $this->rc->config->get('calendar_categories', $this->default_categories);
   }
 
   /**
    * Create instances of a recurring event
    *
    * @param array  Hash array with event properties
    * @param object DateTime Start date of the recurrence window
    * @param object DateTime End date of the recurrence window
    * @return array List of recurring event instances
    */
   public function get_recurring_events($event, $start, $end = null)
   {
     // load the given event data into a libkolabxml container
     if (!$event['_formatobj']) {
       $event_xml = new kolab_format_event();
       $event_xml->set($event);
       $event['_formatobj'] = $event_xml;
     }
 
     $this->_read_calendars();
     $storage = reset($this->calendars);
     return $storage->get_recurring_events($event, $start, $end);
   }
 
   /**
    *
    */
   private function get_recurrence_count($event, $dtstart)
   {
     // use libkolab to compute recurring events
     if (class_exists('kolabcalendaring') && $event['_formatobj']) {
         $recurrence = new kolab_date_recurrence($event['_formatobj']);
     }
     else {
       // fallback to local recurrence implementation
       require_once($this->cal->home . '/lib/calendar_recurrence.php');
       $recurrence = new calendar_recurrence($this->cal, $event);
     }
 
     $count = 0;
     while (($next_event = $recurrence->next_instance()) && $next_event['start'] <= $dtstart && $count < 1000) {
       $count++;
     }
 
     return $count;
   }
 
   /**
    * Fetch free/busy information from a person within the given range
    */
   public function get_freebusy_list($email, $start, $end)
   {
     if (empty($email)/* || $end < time()*/)
       return false;
 
     // map vcalendar fbtypes to internal values
     $fbtypemap = array(
       'FREE' => calendar::FREEBUSY_FREE,
       'BUSY-TENTATIVE' => calendar::FREEBUSY_TENTATIVE,
       'X-OUT-OF-OFFICE' => calendar::FREEBUSY_OOF,
       'OOF' => calendar::FREEBUSY_OOF);
 
     // ask kolab server first
     try {
       $request_config = array(
         'store_body'       => true,
         'follow_redirects' => true,
       );
       $request  = libkolab::http_request(kolab_storage::get_freebusy_url($email), 'GET', $request_config);
       $response = $request->send();
 
       // authentication required
       if ($response->getStatus() == 401) {
         $request->setAuth($this->rc->user->get_username(), $this->rc->decrypt($_SESSION['password']));
         $response = $request->send();
       }
 
       if ($response->getStatus() == 200)
         $fbdata = $response->getBody();
 
       unset($request, $response);
     }
     catch (Exception $e) {
       PEAR::raiseError("Error fetching free/busy information: " . $e->getMessage());
     }
 
     // get free-busy url from contacts
     if (!$fbdata) {
       $fburl = null;
       foreach ((array)$this->rc->config->get('autocomplete_addressbooks', 'sql') as $book) {
         $abook = $this->rc->get_address_book($book);
 
         if ($result = $abook->search(array('email'), $email, true, true, true/*, 'freebusyurl'*/)) {
           while ($contact = $result->iterate()) {
             if ($fburl = $contact['freebusyurl']) {
               $fbdata = @file_get_contents($fburl);
               break;
             }
           }
         }
 
         if ($fbdata)
           break;
       }
     }
 
     // parse free-busy information using Horde classes
     if ($fbdata) {
       $ical = $this->cal->get_ical();
       $ical->import($fbdata);
       if ($fb = $ical->freebusy) {
         $result = array();
         foreach ($fb['periods'] as $tuple) {
           list($from, $to, $type) = $tuple;
           $result[] = array($from->format('U'), $to->format('U'), isset($fbtypemap[$type]) ? $fbtypemap[$type] : calendar::FREEBUSY_BUSY);
         }
 
         // we take 'dummy' free-busy lists as "unknown"
         if (empty($result) && !empty($fb['comment']) && stripos($fb['comment'], 'dummy'))
           return false;
 
         // set period from $start till the begin of the free-busy information as 'unknown'
         if ($fb['start'] && ($fbstart = $fb['start']->format('U')) && $start < $fbstart) {
           array_unshift($result, array($start, $fbstart, calendar::FREEBUSY_UNKNOWN));
         }
         // pad period till $end with status 'unknown'
         if ($fb['end'] && ($fbend = $fb['end']->format('U')) && $fbend < $end) {
           $result[] = array($fbend, $end, calendar::FREEBUSY_UNKNOWN);
         }
 
         return $result;
       }
     }
 
     return false;
   }
 
   /**
    * Handler to push folder triggers when sent from client.
    * Used to push free-busy changes asynchronously after updating an event
    */
   public function push_freebusy()
   {
     // make shure triggering completes
     set_time_limit(0);
     ignore_user_abort(true);
 
     $cal = rcube_utils::get_input_value('source', rcube_utils::INPUT_GPC);
     if (!($cal = $this->get_calendar($cal)))
       return false;
 
     // trigger updates on folder
     $trigger = $cal->storage->trigger();
     if (is_object($trigger) && is_a($trigger, 'PEAR_Error')) {
       rcube::raise_error(array(
         'code' => 900, 'type' => 'php',
         'file' => __FILE__, 'line' => __LINE__,
         'message' => "Failed triggering folder. Error was " . $trigger->getMessage()),
         true, false);
     }
 
     exit;
   }
 
 
   /**
    * Convert from driver format to external caledar app data
    */
   public static function to_rcube_event(&$record)
   {
     if (!is_array($record))
       return $record;
 
     $record['id'] = $record['uid'];
 
     if ($record['_instance']) {
       $record['id'] .= '-' . $record['_instance'];
 
       if (!$record['recurrence_id'] && !empty($record['recurrence']))
         $record['recurrence_id'] = $record['uid'];
     }
 
     // all-day events go from 12:00 - 13:00
     if (is_a($record['start'], 'DateTime') && $record['end'] <= $record['start'] && $record['allday']) {
       $record['end'] = clone $record['start'];
       $record['end']->add(new DateInterval('PT1H'));
     }
 
     // translate internal '_attachments' to external 'attachments' list
     if (!empty($record['_attachments'])) {
       foreach ($record['_attachments'] as $key => $attachment) {
         if ($attachment !== false) {
           if (!$attachment['name'])
             $attachment['name'] = $key;
 
           unset($attachment['path'], $attachment['content']);
           $attachments[] = $attachment;
         }
       }
 
       $record['attachments'] = $attachments;
     }
 
     if (!empty($record['attendees'])) {
       foreach ((array)$record['attendees'] as $i => $attendee) {
         if (is_array($attendee['delegated-from'])) {
           $record['attendees'][$i]['delegated-from'] = join(', ', $attendee['delegated-from']);
         }
         if (is_array($attendee['delegated-to'])) {
           $record['attendees'][$i]['delegated-to'] = join(', ', $attendee['delegated-to']);
         }
       }
     }
 
     // Roundcube only supports one category assignment
     if (is_array($record['categories']))
       $record['categories'] = $record['categories'][0];
 
     // the cancelled flag transltes into status=CANCELLED
     if ($record['cancelled'])
       $record['status'] = 'CANCELLED';
 
     // The web client only supports DISPLAY type of alarms
     if (!empty($record['alarms']))
       $record['alarms'] = preg_replace('/:[A-Z]+$/', ':DISPLAY', $record['alarms']);
 
     // remove empty recurrence array
     if (empty($record['recurrence']))
       unset($record['recurrence']);
 
     // clean up exception data
     if (is_array($record['recurrence']['EXCEPTIONS'])) {
       array_walk($record['recurrence']['EXCEPTIONS'], function(&$exception) {
         unset($exception['_mailbox'], $exception['_msguid'], $exception['_formatobj'], $exception['_attachments']);
       });
     }
 
     unset($record['_mailbox'], $record['_msguid'], $record['_type'], $record['_size'],
       $record['_formatobj'], $record['_attachments'], $record['exceptions'], $record['x-custom']);
 
     return $record;
   }
 
   /**
    *
    */
   public static function from_rcube_event($event, $old = array())
   {
     // in kolab_storage attachments are indexed by content-id
     if (is_array($event['attachments']) || !empty($event['deleted_attachments'])) {
       $event['_attachments'] = array();
 
       foreach ($event['attachments'] as $attachment) {
         $key = null;
         // Roundcube ID has nothing to do with the storage ID, remove it
         if ($attachment['content'] || $attachment['path']) {
           unset($attachment['id']);
         }
         else {
           foreach ((array)$old['_attachments'] as $cid => $oldatt) {
             if ($attachment['id'] == $oldatt['id'])
               $key = $cid;
           }
         }
 
         // flagged for deletion => set to false
         if ($attachment['_deleted'] || in_array($attachment['id'], (array)$event['deleted_attachments'])) {
           $event['_attachments'][$key] = false;
         }
         // replace existing entry
         else if ($key) {
           $event['_attachments'][$key] = $attachment;
         }
         // append as new attachment
         else {
           $event['_attachments'][] = $attachment;
         }
       }
 
       $event['_attachments'] = array_merge((array)$old['_attachments'], $event['_attachments']);
 
       // attachments flagged for deletion => set to false
       foreach ($event['_attachments'] as $key => $attachment) {
         if ($attachment['_deleted'] || in_array($attachment['id'], (array)$event['deleted_attachments'])) {
           $event['_attachments'][$key] = false;
         }
       }
     }
 
     return $event;
   }
 
 
   /**
    * Set CSS class according to the event's attendde partstat
    */
   public static function add_partstat_class($event, $partstats, $user = null)
   {
     // set classes according to PARTSTAT
     if (is_array($event['attendees'])) {
       $user_emails = libcalendaring::get_instance()->get_user_emails($user);
       $partstat = 'UNKNOWN';
       foreach ($event['attendees'] as $attendee) {
         if (in_array($attendee['email'], $user_emails)) {
           $partstat = $attendee['status'];
           break;
         }
       }
 
       if (in_array($partstat, $partstats)) {
         $event['className'] = trim($event['className'] . ' fc-invitation-' . strtolower($partstat));
       }
     }
 
     return $event;
   }
 
   /**
    * Provide a list of revisions for the given event
    *
    * @param array  $event Hash array with event properties
    *
    * @return array List of changes, each as a hash array
    * @see calendar_driver::get_event_changelog()
    */
   public function get_event_changelog($event)
   {
     if (empty($this->bonnie_api)) {
       return false;
     }
 
     list($uid, $mailbox, $msguid) = $this->_resolve_event_identity($event);
 
     $result = $this->bonnie_api->changelog('event', $uid, $mailbox, $msguid);
     if (is_array($result) && $result['uid'] == $uid) {
       return $result['changes'];
     }
 
     return false;
   }
 
   /**
    * Get a list of property changes beteen two revisions of an event
    *
    * @param array  $event Hash array with event properties
    * @param mixed  $rev1  Old Revision
    * @param mixed  $rev2  New Revision
    *
    * @return array List of property changes, each as a hash array
    * @see calendar_driver::get_event_diff()
    */
   public function get_event_diff($event, $rev1, $rev2)
   {
     if (empty($this->bonnie_api)) {
       return false;
     }
 
     list($uid, $mailbox, $msguid) = $this->_resolve_event_identity($event);
 
     // get diff for the requested recurrence instance
     $instance_id = $event['id'] != $uid ? substr($event['id'], strlen($uid) + 1) : null;
 
     // call Bonnie API
     $result = $this->bonnie_api->diff('event', $uid, $rev1, $rev2, $mailbox, $msguid, $instance_id);
     if (is_array($result) && $result['uid'] == $uid) {
       $result['rev1'] = $rev1;
       $result['rev2'] = $rev2;
 
       $keymap = array(
         'dtstart'  => 'start',
         'dtend'    => 'end',
         'dstamp'   => 'changed',
         'summary'  => 'title',
         'alarm'    => 'alarms',
         'attendee' => 'attendees',
         'attach'   => 'attachments',
         'rrule'    => 'recurrence',
         'transparency' => 'free_busy',
         'classification' => 'sensitivity',
         'lastmodified-date' => 'changed',
       );
       $prop_keymaps = array(
         'attachments' => array('fmttype' => 'mimetype', 'label' => 'name'),
         'attendees'   => array('partstat' => 'status'),
       );
       $special_changes = array();
 
       // map kolab event properties to keys the client expects
       array_walk($result['changes'], function(&$change, $i) use ($keymap, $prop_keymaps, $special_changes) {
         if (array_key_exists($change['property'], $keymap)) {
           $change['property'] = $keymap[$change['property']];
         }
         // translate free_busy values
         if ($change['property'] == 'free_busy') {
           $change['old'] = $old['old'] ? 'free' : 'busy';
           $change['new'] = $old['new'] ? 'free' : 'busy';
         }
         // map alarms trigger value
         if ($change['property'] == 'alarms') {
           if (is_array($change['old']) && is_array($change['old']['trigger']))
             $change['old']['trigger'] = $change['old']['trigger']['value'];
           if (is_array($change['new']) && is_array($change['new']['trigger']))
             $change['new']['trigger'] = $change['new']['trigger']['value'];
         }
         // make all property keys uppercase
         if ($change['property'] == 'recurrence') {
           $special_changes['recurrence'] = $i;
           foreach (array('old','new') as $m) {
             if (is_array($change[$m])) {
               $props = array();
               foreach ($change[$m] as $k => $v)
                 $props[strtoupper($k)] = $v;
               $change[$m] = $props;
             }
           }
         }
         // map property keys names
         if (is_array($prop_keymaps[$change['property']])) {
           foreach ($prop_keymaps[$change['property']] as $k => $dest) {
             if (is_array($change['old']) && array_key_exists($k, $change['old'])) {
               $change['old'][$dest] = $change['old'][$k];
               unset($change['old'][$k]);
             }
             if (is_array($change['new']) && array_key_exists($k, $change['new'])) {
               $change['new'][$dest] = $change['new'][$k];
               unset($change['new'][$k]);
             }
           }
         }
 
         if ($change['property'] == 'exdate') {
           $special_changes['exdate'] = $i;
         }
         else if ($change['property'] == 'rdate') {
           $special_changes['rdate'] = $i;
         }
       });
 
       // merge some recurrence changes
       foreach (array('exdate','rdate') as $prop) {
         if (array_key_exists($prop, $special_changes)) {
           $exdate = $result['changes'][$special_changes[$prop]];
           if (array_key_exists('recurrence', $special_changes)) {
             $recurrence = &$result['changes'][$special_changes['recurrence']];
           }
           else {
             $i = count($result['changes']);
             $result['changes'][$i] = array('property' => 'recurrence', 'old' => array(), 'new' => array());
             $recurrence = &$result['changes'][$i]['recurrence'];
           }
           $key = strtoupper($prop);
           $recurrence['old'][$key] = $exdate['old'];
           $recurrence['new'][$key] = $exdate['new'];
           unset($result['changes'][$special_changes[$prop]]);
         }
       }
 
       return $result;
     }
 
     return false;
   }
 
   /**
    * Return full data of a specific revision of an event
    *
    * @param array  Hash array with event properties
    * @param mixed  $rev Revision number
    *
    * @return array Event object as hash array
    * @see calendar_driver::get_event_revison()
    */
   public function get_event_revison($event, $rev, $internal = false)
   {
     if (empty($this->bonnie_api)) {
       return false;
     }
 
     $eventid = $event['id'];
     $calid = $event['calendar'];
     list($uid, $mailbox, $msguid) = $this->_resolve_event_identity($event);
 
     // call Bonnie API
     $result = $this->bonnie_api->get('event', $uid, $rev, $mailbox, $msguid);
     if (is_array($result) && $result['uid'] == $uid && !empty($result['xml'])) {
       $format = kolab_format::factory('event');
       $format->load($result['xml']);
       $event = $format->to_array();
       $format->get_attachments($event, true);
 
       // get the right instance from a recurring event
       if ($eventid != $event['uid']) {
         $instance_id = substr($eventid, strlen($event['uid']) + 1);
 
         // check for recurrence exception first
         if ($instance = $format->get_instance($instance_id)) {
           $event = $instance;
         }
         else {
           // not a exception, compute recurrence...
           $event['_formatobj'] = $format;
           $recurrence_date = rcube_utils::anytodatetime($instance_id, $event['start']->getTimezone());
           foreach ($this->get_recurring_events($event, $event['start'], $recurrence_date) as $instance) {
             if ($instance['id'] == $eventid) {
               $event = $instance;
               break;
             }
           }
         }
       }
 
       if ($format->is_valid()) {
         $event['calendar'] = $calid;
         $event['rev'] = $result['rev'];
         return $internal ? $event : self::to_rcube_event($event);
       }
     }
 
     return false;
   }
 
   /**
    * Command the backend to restore a certain revision of an event.
    * This shall replace the current event with an older version.
    *
    * @param mixed  UID string or hash array with event properties:
    *        id: Event identifier
    *  calendar: Calendar identifier
    * @param mixed  $rev Revision number
    *
    * @return boolean True on success, False on failure
    */
   public function restore_event_revision($event, $rev)
   {
     if (empty($this->bonnie_api)) {
       return false;
     }
 
     list($uid, $mailbox, $msguid) = $this->_resolve_event_identity($event);
     $calendar = $this->get_calendar($event['calendar']);
     $success = false;
 
     if ($calendar && $calendar->storage && $calendar->editable) {
       if ($raw_msg = $this->bonnie_api->rawdata('event', $uid, $rev, $mailbox)) {
         $imap = $this->rc->get_storage();
 
         // insert $raw_msg as new message
         if ($imap->save_message($calendar->storage->name, $raw_msg, null, false)) {
           $success = true;
 
           // delete old revision from imap and cache
           $imap->delete_message($msguid, $calendar->storage->name);
           $calendar->storage->cache->set($msguid, false);
         }
       }
     }
 
     return $success;
   }
 
   /**
    * Helper method to resolved the given event identifier into uid and folder
    *
    * @return array (uid,folder,msguid) tuple
    */
   private function _resolve_event_identity($event)
   {
     $mailbox = $msguid = null;
     if (is_array($event)) {
       $uid = $event['uid'] ?: $event['id'];
       if (($cal = $this->get_calendar($event['calendar'])) && !($cal instanceof kolab_invitation_calendar)) {
         $mailbox = $cal->get_mailbox_id();
 
         // get event object from storage in order to get the real object uid an msguid
         if ($ev = $cal->get_event($event['id'])) {
           $msguid = $ev['_msguid'];
           $uid = $ev['uid'];
         }
       }
     }
     else {
       $uid = $event;
 
       // get event object from storage in order to get the real object uid an msguid
       if ($ev = $this->get_event($event)) {
         $mailbox = $ev['_mailbox'];
         $msguid = $ev['_msguid'];
         $uid = $ev['uid'];
       }
     }
 
     return array($uid, $mailbox, $msguid);
   }
 
   /**
    * Callback function to produce driver-specific calendar create/edit form
    *
    * @param string Request action 'form-edit|form-new'
    * @param array  Calendar properties (e.g. id, color)
    * @param array  Edit form fields
    *
    * @return string HTML content of the form
    */
   public function calendar_form($action, $calendar, $formfields)
   {
     // show default dialog for birthday calendar
     if (in_array($calendar['id'], array(self::BIRTHDAY_CALENDAR_ID, self::INVITATIONS_CALENDAR_PENDING, self::INVITATIONS_CALENDAR_DECLINED))) {
       if ($calendar['id'] != self::BIRTHDAY_CALENDAR_ID)
         unset($formfields['showalarms']);
       return parent::calendar_form($action, $calendar, $formfields);
     }
 
     if ($calendar['id'] && ($cal = $this->calendars[$calendar['id']])) {
       $folder = $cal->get_realname(); // UTF7
       $color  = $cal->get_color();
     }
     else {
       $folder = '';
       $color  = '';
     }
 
     $hidden_fields[] = array('name' => 'oldname', 'value' => $folder);
 
     $storage = $this->rc->get_storage();
     $delim   = $storage->get_hierarchy_delimiter();
     $form   = array();
 
     if (strlen($folder)) {
       $path_imap = explode($delim, $folder);
       array_pop($path_imap);  // pop off name part
       $path_imap = implode($path_imap, $delim);
 
       $options = $storage->folder_info($folder);
     }
     else {
       $path_imap = '';
     }
 
     // General tab
     $form['props'] = array(
       'name' => $this->rc->gettext('properties'),
     );
 
     // Disable folder name input
     if (!empty($options) && ($options['norename'] || $options['protected'])) {
       $input_name = new html_hiddenfield(array('name' => 'name', 'id' => 'calendar-name'));
       $formfields['name']['value'] = kolab_storage::object_name($folder)
         . $input_name->show($folder);
     }
 
     // calendar name (default field)
     $form['props']['fieldsets']['location'] = array(
       'name'  => $this->rc->gettext('location'),
       'content' => array(
         'name' => $formfields['name']
       ),
     );
 
     if (!empty($options) && ($options['norename'] || $options['protected'])) {
       // prevent user from moving folder
       $hidden_fields[] = array('name' => 'parent', 'value' => $path_imap);
     }
     else {
       $select = kolab_storage::folder_selector('event', array('name' => 'parent', 'id' => 'calendar-parent'), $folder);
       $form['props']['fieldsets']['location']['content']['path'] = array(
         'id' => 'calendar-parent',
         'label' => $this->cal->gettext('parentcalendar'),
         'value' => $select->show(strlen($folder) ? $path_imap : ''),
       );
     }
 
     // calendar color (default field)
     $form['props']['fieldsets']['settings'] = array(
       'name'  => $this->rc->gettext('settings'),
       'content' => array(
         'color' => $formfields['color'],
         'showalarms' => $formfields['showalarms'],
       ),
     );
     
     
     if ($action != 'form-new') {
       $form['sharing'] = array(
           'name'    => rcube::Q($this->cal->gettext('tabsharing')),
           'content' => html::tag('iframe', array(
             'src' => $this->cal->rc->url(array('_action' => 'calendar-acl', 'id' => $calendar['id'], 'framed' => 1)),
             'width' => '100%',
             'height' => 350,
             'border' => 0,
             'style' => 'border:0'),
         ''),
       );
     }
 
     $this->form_html = '';
     if (is_array($hidden_fields)) {
         foreach ($hidden_fields as $field) {
             $hiddenfield = new html_hiddenfield($field);
             $this->form_html .= $hiddenfield->show() . "\n";
         }
     }
 
     // Create form output
     foreach ($form as $tab) {
       if (!empty($tab['fieldsets']) && is_array($tab['fieldsets'])) {
         $content = '';
         foreach ($tab['fieldsets'] as $fieldset) {
           $subcontent = $this->get_form_part($fieldset);
           if ($subcontent) {
             $content .= html::tag('fieldset', null, html::tag('legend', null, rcube::Q($fieldset['name'])) . $subcontent) ."\n";
           }
         }
       }
       else {
         $content = $this->get_form_part($tab);
       }
 
       if ($content) {
         $this->form_html .= html::tag('fieldset', null, html::tag('legend', null, rcube::Q($tab['name'])) . $content) ."\n";
       }
     }
 
     // Parse form template for skin-dependent stuff
     $this->rc->output->add_handler('calendarform', array($this, 'calendar_form_html'));
     return $this->rc->output->parse('calendar.kolabform', false, false);
   }
 
   /**
    * Handler for template object
    */
   public function calendar_form_html()
   {
     return $this->form_html;
   }
 
   /**
    * Helper function used in calendar_form_content(). Creates a part of the form.
    */
   private function get_form_part($form)
   {
     $content = '';
 
     if (is_array($form['content']) && !empty($form['content'])) {
       $table = new html_table(array('cols' => 2));
       foreach ($form['content'] as $col => $colprop) {
-        $label = !empty($colprop['label']) ? $colprop['label'] : rcube_label($col);
+        $label = !empty($colprop['label']) ? $colprop['label'] : $this->rc->gettext($col);
 
         $table->add('title', html::label($colprop['id'], rcube::Q($label)));
         $table->add(null, $colprop['value']);
       }
       $content = $table->show();
     }
     else {
       $content = $form['content'];
     }
 
     return $content;
   }
 
 
   /**
    * Handler to render ACL form for a calendar folder
    */
   public function calendar_acl()
   {
     $this->rc->output->add_handler('folderacl', array($this, 'calendar_acl_form'));
     $this->rc->output->send('calendar.kolabacl');
   }
 
   /**
    * Handler for ACL form template object
    */
   public function calendar_acl_form()
   {
     $calid = rcube_utils::get_input_value('_id', rcube_utils::INPUT_GPC);
     if ($calid && ($cal = $this->get_calendar($calid))) {
       $folder = $cal->get_realname(); // UTF7
       $color  = $cal->get_color();
     }
     else {
       $folder = '';
       $color  = '';
     }
 
     $storage = $this->rc->get_storage();
     $delim   = $storage->get_hierarchy_delimiter();
     $form   = array();
 
     if (strlen($folder)) {
       $path_imap = explode($delim, $folder);
       array_pop($path_imap);  // pop off name part
       $path_imap = implode($path_imap, $delim);
 
       $options = $storage->folder_info($folder);
 
       // Allow plugins to modify the form content (e.g. with ACL form)
       $plugin = $this->rc->plugins->exec_hook('calendar_form_kolab',
         array('form' => $form, 'options' => $options, 'name' => $folder));
     }
 
     if (!$plugin['form']['sharing']['content'])
         $plugin['form']['sharing']['content'] = html::div('hint', $this->cal->gettext('aclnorights'));
 
     return $plugin['form']['sharing']['content'];
   }
 
   /**
    * Handler for user_delete plugin hook
    */
   public function user_delete($args)
   {
     $db = $this->rc->get_dbh();
     foreach (array('kolab_alarms', 'itipinvitations') as $table) {
       $db->query("DELETE FROM " . $this->rc->db->table_name($table, true)
         . " WHERE `user_id` = ?", $args['user']->ID);
     }
   }
 }
diff --git a/plugins/calendar/lib/calendar_ui.php b/plugins/calendar/lib/calendar_ui.php
index 6ca19c97..49594a79 100644
--- a/plugins/calendar/lib/calendar_ui.php
+++ b/plugins/calendar/lib/calendar_ui.php
@@ -1,881 +1,881 @@
 <?php
 /**
  * User Interface class for the Calendar plugin
  *
  * @author Lazlo Westerhof <hello@lazlo.me>
  * @author Thomas Bruederli <bruederli@kolabsys.com>
  *
  * Copyright (C) 2010, Lazlo Westerhof <hello@lazlo.me>
  * Copyright (C) 2014, Kolab Systems AG <contact@kolabsys.com>
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
  * published by the Free Software Foundation, either version 3 of the
  * License, or (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  * GNU Affero General Public License for more details.
  *
  * You should have received a copy of the GNU Affero General Public License
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 
 
 class calendar_ui
 {
   private $rc;
   private $cal;
   private $ready = false;
   public $screen;
 
   function __construct($cal)
   {
     $this->cal = $cal;
     $this->rc = $cal->rc;
     $this->screen = $this->rc->task == 'calendar' ? ($this->rc->action ? $this->rc->action: 'calendar') : 'other';
   }
     
   /**
    * Calendar UI initialization and requests handlers
    */
   public function init()
   {
     if ($this->ready)  // already done
       return;
       
     // add taskbar button
     $this->cal->add_button(array(
       'command' => 'calendar',
       'class'   => 'button-calendar',
       'classsel' => 'button-calendar button-selected',
       'innerclass' => 'button-inner',
       'label'   => 'calendar.calendar',
       ), 'taskbar');
     
     // load basic client script
     $this->cal->include_script('calendar_base.js');
     
     $skin_path = $this->cal->local_skin_path();
     $this->cal->include_stylesheet($skin_path . '/calendar.css');
     
     $this->ready = true;
   }
 
   /**
    * Register handler methods for the template engine
    */
   public function init_templates()
   {
     $this->cal->register_handler('plugin.calendar_css', array($this, 'calendar_css'));
     $this->cal->register_handler('plugin.calendar_list', array($this, 'calendar_list'));
     $this->cal->register_handler('plugin.calendar_select', array($this, 'calendar_select'));
     $this->cal->register_handler('plugin.identity_select', array($this, 'identity_select'));
     $this->cal->register_handler('plugin.category_select', array($this, 'category_select'));
     $this->cal->register_handler('plugin.status_select', array($this, 'status_select'));
     $this->cal->register_handler('plugin.freebusy_select', array($this, 'freebusy_select'));
     $this->cal->register_handler('plugin.priority_select', array($this, 'priority_select'));
     $this->cal->register_handler('plugin.sensitivity_select', array($this, 'sensitivity_select'));
     $this->cal->register_handler('plugin.alarm_select', array($this, 'alarm_select'));
     $this->cal->register_handler('plugin.recurrence_form', array($this->cal->lib, 'recurrence_form'));
     $this->cal->register_handler('plugin.attachments_form', array($this, 'attachments_form'));
     $this->cal->register_handler('plugin.attachments_list', array($this, 'attachments_list'));
     $this->cal->register_handler('plugin.filedroparea', array($this, 'file_drop_area'));
     $this->cal->register_handler('plugin.attendees_list', array($this, 'attendees_list'));
     $this->cal->register_handler('plugin.attendees_form', array($this, 'attendees_form'));
     $this->cal->register_handler('plugin.resources_form', array($this, 'resources_form'));
     $this->cal->register_handler('plugin.resources_list', array($this, 'resources_list'));
     $this->cal->register_handler('plugin.resources_searchform', array($this, 'resources_search_form'));
     $this->cal->register_handler('plugin.resource_info', array($this, 'resource_info'));
     $this->cal->register_handler('plugin.resource_calendar', array($this, 'resource_calendar'));
     $this->cal->register_handler('plugin.attendees_freebusy_table', array($this, 'attendees_freebusy_table'));
     $this->cal->register_handler('plugin.edit_attendees_notify', array($this, 'edit_attendees_notify'));
     $this->cal->register_handler('plugin.edit_recurring_warning', array($this, 'recurring_event_warning'));
     $this->cal->register_handler('plugin.event_rsvp_buttons', array($this, 'event_rsvp_buttons'));
     $this->cal->register_handler('plugin.angenda_options', array($this, 'angenda_options'));
     $this->cal->register_handler('plugin.events_import_form', array($this, 'events_import_form'));
     $this->cal->register_handler('plugin.events_export_form', array($this, 'events_export_form'));
     $this->cal->register_handler('plugin.object_changelog_table', array('libkolab', 'object_changelog_table'));
     $this->cal->register_handler('plugin.searchform', array($this->rc->output, 'search_form'));  // use generic method from rcube_template
   }
 
   /**
    * Adds CSS stylesheets to the page header
    */
   public function addCSS()
   {
     $skin_path = $this->cal->local_skin_path();
     $this->cal->include_stylesheet($skin_path . '/fullcalendar.css');
   }
 
   /**
    * Adds JS files to the page header
    */
   public function addJS()
   {
     $this->cal->include_script('calendar_ui.js');
     $this->cal->include_script('lib/js/fullcalendar.js');
     $this->rc->output->include_script('treelist.js');
 
     // include kolab folderlist widget if available
     if (in_array('libkolab', $this->cal->api->loaded_plugins())) {
         $this->cal->api->include_script('libkolab/js/folderlist.js');
         $this->cal->api->include_script('libkolab/js/audittrail.js');
     }
 
     jqueryui::miniColors();
   }
 
   /**
    *
    */
   function calendar_css($attrib = array())
   {
     $mode = $this->rc->config->get('calendar_event_coloring', $this->cal->defaults['calendar_event_coloring']);
     $categories = $this->cal->driver->list_categories();
     $css = "\n";
     
     foreach ((array)$categories as $class => $color) {
       if (empty($color))
         continue;
       
       $class = 'cat-' . asciiwords(strtolower($class), true);
       $css  .= ".$class { color: #$color }\n";
       if ($mode > 0) {
         if ($mode == 2) {
           $css .= ".fc-event-$class .fc-event-bg {";
           $css .= " opacity: 0.9;";
           $css .= " filter: alpha(opacity=90);";
         }
         else {
           $css .= ".fc-event-$class.fc-event-skin, ";
           $css .= ".fc-event-$class .fc-event-skin, ";
           $css .= ".fc-event-$class .fc-event-inner {";
         }
         $css .= " background-color: #" . $color . ";";
         if ($mode % 2)
           $css .= " border-color: #$color;";
         $css .= "}\n";
       }
     }
     
     $calendars = $this->cal->driver->list_calendars();
     foreach ((array)$calendars as $id => $prop) {
       if (!$prop['color'])
         continue;
       $css .= $this->calendar_css_classes($id, $prop, $mode);
     }
     
     return html::tag('style', array('type' => 'text/css'), $css);
   }
 
   /**
    *
    */
   public function calendar_css_classes($id, $prop, $mode)
   {
     $color = $prop['color'];
     $class = 'cal-' . asciiwords($id, true);
     $css .= "li .$class, #eventshow .$class { color: #$color }\n";
 
     if ($mode != 1) {
       if ($mode == 3) {
         $css .= ".fc-event-$class .fc-event-bg {";
         $css .= " opacity: 0.9;";
         $css .= " filter: alpha(opacity=90);";
       }
       else {
         $css .= ".fc-event-$class, ";
         $css .= ".fc-event-$class .fc-event-inner {";
       }
       if (!$attrib['printmode'])
         $css .= " background-color: #$color;";
       if ($mode % 2 == 0)
       $css .= " border-color: #$color;";
       $css .= "}\n";
     }
 
     return $css . ".$class .handle { background-color: #$color; }\n";
   }
 
   /**
    *
    */
   function calendar_list($attrib = array())
   {
     $html = '';
     $jsenv = array();
     $tree = true;
     $calendars = $this->cal->driver->list_calendars(0, $tree);
 
     // walk folder tree
     if (is_object($tree)) {
       $html = $this->list_tree_html($tree, $calendars, $jsenv, $attrib);
 
       // append birthdays calendar which isn't part of $tree
       if ($bdaycal = $calendars[calendar_driver::BIRTHDAY_CALENDAR_ID]) {
         $calendars = array(calendar_driver::BIRTHDAY_CALENDAR_ID => $bdaycal);
       }
       else {
         $calendars = array();  // clear array for flat listing
       }
     }
     else {
       // fall-back to flat folder listing
       $attrib['class'] .= ' flat';
     }
 
     foreach ((array)$calendars as $id => $prop) {
       if ($attrib['activeonly'] && !$prop['active'])
         continue;
 
       $html .= html::tag('li', array('id' => 'rcmlical' . $id, 'class' => $prop['group']),
         $content = $this->calendar_list_item($id, $prop, $jsenv, $attrib['activeonly'])
       );
     }
 
     $this->rc->output->set_env('calendars', $jsenv);
     $this->rc->output->add_gui_object('calendarslist', $attrib['id']);
 
     return html::tag('ul', $attrib, $html, html::$common_attrib);
   }
 
   /**
    * Return html for a structured list <ul> for the folder tree
    */
   public function list_tree_html($node, $data, &$jsenv, $attrib)
   {
     $out = '';
     foreach ($node->children as $folder) {
       $id = $folder->id;
       $prop = $data[$id];
       $is_collapsed = false; // TODO: determine this somehow?
 
       $content = $this->calendar_list_item($id, $prop, $jsenv, $attrib['activeonly']);
 
       if (!empty($folder->children)) {
         $content .= html::tag('ul', array('style' => ($is_collapsed ? "display:none;" : null)),
           $this->list_tree_html($folder, $data, $jsenv, $attrib));
       }
 
       if (strlen($content)) {
         $out .= html::tag('li', array(
             'id' => 'rcmlical' . rcube_utils::html_identifier($id),
             'class' => $prop['group'] . ($prop['virtual'] ? ' virtual' : ''),
           ),
           $content);
       }
     }
 
     return $out;
   }
 
   /**
    * Helper method to build a calendar list item (HTML content and js data)
    */
   public function calendar_list_item($id, $prop, &$jsenv, $activeonly = false)
   {
     // enrich calendar properties with settings from the driver
     if (!$prop['virtual']) {
       unset($prop['user_id']);
       $prop['alarms']      = $this->cal->driver->alarms;
       $prop['attendees']   = $this->cal->driver->attendees;
       $prop['freebusy']    = $this->cal->driver->freebusy;
       $prop['attachments'] = $this->cal->driver->attachments;
       $prop['undelete']    = $this->cal->driver->undelete;
       $prop['feedurl']     = $this->cal->get_url(array('_cal' => $this->cal->ical_feed_hash($id) . '.ics', 'action' => 'feed'));
 
       $jsenv[$id] = $prop;
     }
 
     $classes = array('calendar', 'cal-'  . asciiwords($id, true));
     $title = $prop['title'] ?: ($prop['name'] != $prop['listname'] || strlen($prop['name']) > 25 ?
       html_entity_decode($prop['name'], ENT_COMPAT, RCUBE_CHARSET) : '');
 
     if ($prop['virtual'])
       $classes[] = 'virtual';
     else if (!$prop['editable'])
       $classes[] = 'readonly';
     if ($prop['subscribed'])
       $classes[] = 'subscribed';
     if ($prop['subscribed'] === 2)
       $classes[] = 'partial';
     if ($prop['class'])
       $classes[] = $prop['class'];
 
     $content = '';
     if (!$activeonly || $prop['active']) {
       $label_id = 'cl:' . $id;
       $content = html::div(join(' ', $classes),
         html::span(array('class' => 'calname', 'id' => $label_id, 'title' => $title), $prop['editname'] ? rcube::Q($prop['editname']) : $prop['listname']) .
         ($prop['virtual'] ? '' :
           html::tag('input', array('type' => 'checkbox', 'name' => '_cal[]', 'value' => $id, 'checked' => $prop['active'], 'aria-labelledby' => $label_id), '') .
           html::span('actions', 
             ($prop['removable'] ? html::a(array('href' => '#', 'class' => 'remove', 'title' => $this->cal->gettext('removelist')), ' ') : '') .
             html::a(array('href' => '#', 'class' => 'quickview', 'title' => $this->cal->gettext('quickview'), 'role' => 'checkbox', 'aria-checked' => 'false'), '') .
             (isset($prop['subscribed']) ? html::a(array('href' => '#', 'class' => 'subscribed', 'title' => $this->cal->gettext('calendarsubscribe'), 'role' => 'checkbox', 'aria-checked' => $prop['subscribed'] ? 'true' : 'false'), ' ') : '')
           ) .
           html::span(array('class' => 'handle', 'style' => "background-color: #" . ($prop['color'] ?: 'f00')), '&nbsp;')
         )
       );
     }
 
     return $content;
   }
 
   /**
    *
    */
   function angenda_options($attrib = array())
   {
     $attrib += array('id' => 'agendaoptions');
     $attrib['style'] .= 'display:none';
     
     $select_range = new html_select(array('name' => 'listrange', 'id' => 'agenda-listrange'));
     $select_range->add(1 . ' ' . preg_replace('/\(.+\)/', '', $this->cal->lib->gettext('days')), $days);
     foreach (array(2,5,7,14,30,60,90,180,365) as $days)
       $select_range->add($days . ' ' . preg_replace('/\(|\)/', '', $this->cal->lib->gettext('days')), $days);
     
     $html .= html::label('agenda-listrange', $this->cal->gettext('listrange'));
     $html .= $select_range->show($this->rc->config->get('calendar_agenda_range', $this->cal->defaults['calendar_agenda_range']));
     
     $select_sections = new html_select(array('name' => 'listsections', 'id' => 'agenda-listsections'));
     $select_sections->add('---', '');
     foreach (array('day' => 'libcalendaring.days', 'week' => 'libcalendaring.weeks', 'month' => 'libcalendaring.months', 'smart' => 'calendar.smartsections') as $val => $label)
       $select_sections->add(preg_replace('/\(|\)/', '', ucfirst($this->rc->gettext($label))), $val);
     
     $html .= html::span('spacer', '&nbsp;');
     $html .= html::label('agenda-listsections', $this->cal->gettext('listsections'));
     $html .= $select_sections->show($this->rc->config->get('calendar_agenda_sections', $this->cal->defaults['calendar_agenda_sections']));
     
     return html::div($attrib, $html);
   }
 
   /**
    * Render a HTML select box for calendar selection
    */
   function calendar_select($attrib = array())
   {
     $attrib['name']       = 'calendar';
     $attrib['is_escaped'] = true;
     $select = new html_select($attrib);
 
     foreach ((array)$this->cal->driver->list_calendars() as $id => $prop) {
       if ($prop['editable'] || strpos($prop['rights'], 'i') !== false)
         $select->add($prop['name'], $id);
     }
 
     return $select->show(null);
   }
 
   /**
    * Render a HTML select box for user identity selection
    */
   function identity_select($attrib = array())
   {
     $attrib['name'] = 'identity';
     $select         = new html_select($attrib);
     $identities     = $this->rc->user->list_emails();
 
     foreach ($identities as $ident) {
         $select->add(format_email_recipient($ident['email'], $ident['name']), $ident['identity_id']);
     }
 
     return $select->show(null);
   }
 
   /**
    * Render a HTML select box to select an event category
    */
   function category_select($attrib = array())
   {
     $attrib['name'] = 'categories';
     $select = new html_select($attrib);
     $select->add('---', '');
     foreach (array_keys((array)$this->cal->driver->list_categories()) as $cat) {
       $select->add($cat, $cat);
     }
 
     return $select->show(null);
   }
 
   /**
    * Render a HTML select box for status property
    */
   function status_select($attrib = array())
   {
     $attrib['name'] = 'status';
     $select = new html_select($attrib);
     $select->add('---', '');
     $select->add($this->cal->gettext('status-confirmed'), 'CONFIRMED');
     $select->add($this->cal->gettext('status-cancelled'), 'CANCELLED');
     //$select->add($this->cal->gettext('tentative'), 'TENTATIVE');
     return $select->show(null);
   }
 
   /**
    * Render a HTML select box for free/busy/out-of-office property
    */
   function freebusy_select($attrib = array())
   {
     $attrib['name'] = 'freebusy';
     $select = new html_select($attrib);
     $select->add($this->cal->gettext('free'), 'free');
     $select->add($this->cal->gettext('busy'), 'busy');
     // out-of-office is not supported by libkolabxml (#3220)
     // $select->add($this->cal->gettext('outofoffice'), 'outofoffice');
     $select->add($this->cal->gettext('tentative'), 'tentative');
     return $select->show(null);
   }
 
   /**
    * Render a HTML select for event priorities
    */
   function priority_select($attrib = array())
   {
     $attrib['name'] = 'priority';
     $select = new html_select($attrib);
     $select->add('---', '0');
     $select->add('1 '.$this->cal->gettext('highest'), '1');
     $select->add('2 '.$this->cal->gettext('high'),    '2');
     $select->add('3 ',                                '3');
     $select->add('4 ',                                '4');
     $select->add('5 '.$this->cal->gettext('normal'),  '5');
     $select->add('6 ',                                '6');
     $select->add('7 ',                                '7');
     $select->add('8 '.$this->cal->gettext('low'),     '8');
     $select->add('9 '.$this->cal->gettext('lowest'),  '9');
     return $select->show(null);
   }
   
   /**
    * Render HTML input for sensitivity selection
    */
   function sensitivity_select($attrib = array())
   {
     $attrib['name'] = 'sensitivity';
     $select = new html_select($attrib);
     $select->add($this->cal->gettext('public'), 'public');
     $select->add($this->cal->gettext('private'), 'private');
     $select->add($this->cal->gettext('confidential'), 'confidential');
     return $select->show(null);
   }
   
   /**
    * Render HTML form for alarm configuration
    */
   function alarm_select($attrib = array())
   {
     return $this->cal->lib->alarm_select($attrib, $this->cal->driver->alarm_types, $this->cal->driver->alarm_absolute);
   }
 
   /**
    *
    */
   function edit_attendees_notify($attrib = array())
   {
     $checkbox = new html_checkbox(array('name' => '_notify', 'id' => 'edit-attendees-donotify', 'value' => 1));
     return html::div($attrib, html::label(null, $checkbox->show(1) . ' ' . $this->cal->gettext('sendnotifications')));
   }
 
   /**
    * Generate the form for recurrence settings
    */
   function recurring_event_warning($attrib = array())
   {
     $attrib['id'] = 'edit-recurring-warning';
     
     $radio = new html_radiobutton(array('name' => '_savemode', 'class' => 'edit-recurring-savemode'));
     $form = html::label(null, $radio->show('', array('value' => 'current')) . $this->cal->gettext('currentevent')) . ' ' .
        html::label(null, $radio->show('', array('value' => 'future')) . $this->cal->gettext('futurevents')) . ' ' .
        html::label(null, $radio->show('all', array('value' => 'all')) . $this->cal->gettext('allevents')) . ' ' .
        html::label(null, $radio->show('', array('value' => 'new')) . $this->cal->gettext('saveasnew'));
        
     return html::div($attrib, html::div('message', html::span('ui-icon ui-icon-alert', '') . $this->cal->gettext('changerecurringeventwarning')) . html::div('savemode', $form));
   }
 
   /**
    * Form for uploading and importing events
    */
   function events_import_form($attrib = array())
   {
     if (!$attrib['id'])
       $attrib['id'] = 'rcmImportForm';
 
     // Get max filesize, enable upload progress bar
-    $max_filesize = rcube_upload_init();
+    $max_filesize = $this->rc->upload_init();
 
     $accept = '.ics, text/calendar, text/x-vcalendar, application/ics';
     if (class_exists('ZipArchive', false)) {
       $accept .= ', .zip, application/zip';
     }
 
     $input = new html_inputfield(array(
       'type' => 'file', 'name' => '_data', 'size' => $attrib['uploadfieldsize'],
       'accept' => $accept));
 
     $select = new html_select(array('name' => '_range', 'id' => 'event-import-range'));
     $select->add(array(
         $this->cal->gettext('onemonthback'),
         $this->cal->gettext(array('name' => 'nmonthsback', 'vars' => array('nr'=>2))),
         $this->cal->gettext(array('name' => 'nmonthsback', 'vars' => array('nr'=>3))),
         $this->cal->gettext(array('name' => 'nmonthsback', 'vars' => array('nr'=>6))),
         $this->cal->gettext(array('name' => 'nmonthsback', 'vars' => array('nr'=>12))),
         $this->cal->gettext('all'),
       ),
       array('1','2','3','6','12',0));
 
     $html .= html::div('form-section',
       html::div(null, $input->show()) .
-      html::div('hint', rcube_label(array('name' => 'maxuploadsize', 'vars' => array('size' => $max_filesize))))
+      html::div('hint', $this->rc->gettext(array('name' => 'maxuploadsize', 'vars' => array('size' => $max_filesize))))
     );
 
     $html .= html::div('form-section',
       html::label('event-import-calendar', $this->cal->gettext('calendar')) .
       $this->calendar_select(array('name' => 'calendar', 'id' => 'event-import-calendar'))
     );
 
     $html .= html::div('form-section',
       html::label('event-import-range', $this->cal->gettext('importrange')) .
       $select->show(1)
     );
 
     $this->rc->output->add_gui_object('importform', $attrib['id']);
     $this->rc->output->add_label('import');
 
     return html::tag('form', array('action' => $this->rc->url(array('task' => 'calendar', 'action' => 'import_events')),
       'method' => "post", 'enctype' => 'multipart/form-data', 'id' => $attrib['id']),
       $html
     );
   }
 
   /**
    * Form to select options for exporting events
    */
   function events_export_form($attrib = array())
   {
     if (!$attrib['id'])
       $attrib['id'] = 'rcmExportForm';
 
     $html .= html::div('form-section',
       html::label('event-export-calendar', $this->cal->gettext('calendar')) .
       $this->calendar_select(array('name' => 'calendar', 'id' => 'event-export-calendar'))
     );
 
     $select = new html_select(array('name' => 'range', 'id' => 'event-export-range'));
     $select->add(array(
         $this->cal->gettext('all'),
         $this->cal->gettext('onemonthback'),
         $this->cal->gettext(array('name' => 'nmonthsback', 'vars' => array('nr'=>2))),
         $this->cal->gettext(array('name' => 'nmonthsback', 'vars' => array('nr'=>3))),
         $this->cal->gettext(array('name' => 'nmonthsback', 'vars' => array('nr'=>6))),
         $this->cal->gettext(array('name' => 'nmonthsback', 'vars' => array('nr'=>12))),
         $this->cal->gettext('customdate'),
       ),
       array(0,'1','2','3','6','12','custom'));
 
     $startdate = new html_inputfield(array('name' => 'start', 'size' => 11, 'id' => 'event-export-startdate'));
 
     $html .= html::div('form-section',
       html::label('event-export-range', $this->cal->gettext('exportrange')) .
       $select->show(0) .
       html::span(array('style'=>'display:none'), $startdate->show())
     );
 
     $checkbox = new html_checkbox(array('name' => 'attachments', 'id' => 'event-export-attachments', 'value' => 1));
     $html .= html::div('form-section',
       html::label('event-export-range', $this->cal->gettext('exportattachments')) .
       $checkbox->show(1)
     );
 
     $this->rc->output->add_gui_object('exportform', $attrib['id']);
 
     return html::tag('form', array('action' => $this->rc->url(array('task' => 'calendar', 'action' => 'export_events')),
       'method' => "post", 'id' => $attrib['id']),
       $html
     );
   }
 
   /**
    * Generate the form for event attachments upload
    */
   function attachments_form($attrib = array())
   {
     // add ID if not given
     if (!$attrib['id'])
       $attrib['id'] = 'rcmUploadForm';
 
     // Get max filesize, enable upload progress bar
-    $max_filesize = rcube_upload_init();
+    $max_filesize =$this->rc->upload_init();
 
     $button = new html_inputfield(array('type' => 'button'));
     $input = new html_inputfield(array(
       'type' => 'file', 'name' => '_attachments[]',
       'multiple' => 'multiple', 'size' => $attrib['attachmentfieldsize']));
 
     return html::div($attrib,
       html::div(null, $input->show()) .
       html::div('formbuttons', $button->show($this->rc->gettext('upload'), array('class' => 'button mainaction',
         'onclick' => rcmail_output::JS_OBJECT_NAME . ".upload_file(this.form)"))) .
       html::div('hint', $this->rc->gettext(array('name' => 'maxuploadsize', 'vars' => array('size' => $max_filesize))))
     );
   }
 
   /**
    * Register UI object for HTML5 drag & drop file upload
    */
   function file_drop_area($attrib = array())
   {
       if ($attrib['id']) {
           $this->rc->output->add_gui_object('filedrop', $attrib['id']);
           $this->rc->output->set_env('filedrop', array('action' => 'upload', 'fieldname' => '_attachments'));
       }
   }
 
   /**
    * Generate HTML element for attachments list
    */
   function attachments_list($attrib = array())
   {
     if (!$attrib['id'])
       $attrib['id'] = 'rcmAttachmentList';
 
     $skin_path = $this->cal->local_skin_path();
     if ($attrib['deleteicon']) {
       $_SESSION[calendar::SESSION_KEY . '_deleteicon'] = $skin_path . $attrib['deleteicon'];
       $this->rc->output->set_env('deleteicon', $skin_path . $attrib['deleteicon']);
     }
     if ($attrib['cancelicon'])
       $this->rc->output->set_env('cancelicon', $skin_path . $attrib['cancelicon']);
     if ($attrib['loadingicon'])
       $this->rc->output->set_env('loadingicon', $skin_path . $attrib['loadingicon']);
 
     $this->rc->output->add_gui_object('attachmentlist', $attrib['id']);
     $this->attachmentlist_id = $attrib['id'];
 
     return html::tag('ul', $attrib, '', html::$common_attrib);
   }
 
   /**
    * Handler for calendar form template.
    * The form content could be overriden by the driver
    */
   function calendar_editform($action, $calendar = array())
   {
     // compose default calendar form fields
     $input_name = new html_inputfield(array('name' => 'name', 'id' => 'calendar-name', 'size' => 20));
     $input_color = new html_inputfield(array('name' => 'color', 'id' => 'calendar-color', 'size' => 6));
 
     $formfields = array(
       'name' => array(
         'label' => $this->cal->gettext('name'),
         'value' => $input_name->show($calendar['name']),
         'id' => 'calendar-name',
       ),
       'color' => array(
         'label' => $this->cal->gettext('color'),
         'value' => $input_color->show($calendar['color']),
         'id' => 'calendar-color',
       ),
     );
 
     if ($this->cal->driver->alarms) {
       $checkbox = new html_checkbox(array('name' => 'showalarms', 'id' => 'calendar-showalarms', 'value' => 1));
       $formfields['showalarms'] = array(
         'label' => $this->cal->gettext('showalarms'),
         'value' => $checkbox->show($calendar['showalarms']?1:0),
         'id' => 'calendar-showalarms',
       );
     }
 
     // allow driver to extend or replace the form content
     return html::tag('form', array('action' => "#", 'method' => "get", 'id' => 'calendarpropform'),
       $this->cal->driver->calendar_form($action, $calendar, $formfields)
     );
   }
 
   /**
    *
    */
   function attendees_list($attrib = array())
   {
     // add "noreply" checkbox to attendees table only
     $invitations = strpos($attrib['id'], 'attend') !== false;
 
     $invite = new html_checkbox(array('value' => 1, 'id' => 'edit-attendees-invite'));
     $table  = new html_table(array('cols' => 5 + intval($invitations), 'border' => 0, 'cellpadding' => 0, 'class' => 'rectable'));
 
     $table->add_header('role', $this->cal->gettext('role'));
     $table->add_header('name', $this->cal->gettext($attrib['coltitle'] ?: 'attendee'));
     $table->add_header('availability', $this->cal->gettext('availability'));
     $table->add_header('confirmstate', $this->cal->gettext('confirmstate'));
     if ($invitations) {
       $table->add_header(array('class' => 'invite', 'title' => $this->cal->gettext('sendinvitations')),
         $invite->show(1) . html::label('edit-attendees-invite', $this->cal->gettext('sendinvitations')));
     }
     $table->add_header('options', '');
 
     // hide invite column if disabled by config
     $itip_notify = (int)$this->rc->config->get('calendar_itip_send_option', $this->cal->defaults['calendar_itip_send_option']);
     if ($invitations && !($itip_notify & 2)) {
         $css = sprintf('#%s td.invite, #%s th.invite { display:none !important }', $attrib['id'], $attrib['id']);
         $this->rc->output->add_footer(html::tag('style', array('type' => 'text/css'), $css));
     }
 
     return $table->show($attrib);
   }
 
   /**
    *
    */
   function attendees_form($attrib = array())
   {
     $input    = new html_inputfield(array('name' => 'participant', 'id' => 'edit-attendee-name', 'size' => 30));
     $textarea = new html_textarea(array('name' => 'comment', 'id' => 'edit-attendees-comment',
         'rows' => 4, 'cols' => 55, 'title' => $this->cal->gettext('itipcommenttitle')));
 
     return html::div($attrib,
       html::div(null, $input->show() . " " .
         html::tag('input', array('type' => 'button', 'class' => 'button', 'id' => 'edit-attendee-add', 'value' => $this->cal->gettext('addattendee'))) . " " .
         html::tag('input', array('type' => 'button', 'class' => 'button', 'id' => 'edit-attendee-schedule', 'value' => $this->cal->gettext('scheduletime').'...'))) .
       html::p('attendees-commentbox', html::label(null, $this->cal->gettext('itipcomment') . $textarea->show()))
     );
   }
 
   /**
    *
    */
   function resources_form($attrib = array())
   {
     $input = new html_inputfield(array('name' => 'resource', 'id' => 'edit-resource-name', 'size' => 30));
 
     return html::div($attrib,
       html::div(null, $input->show() . " " .
         html::tag('input', array('type' => 'button', 'class' => 'button', 'id' => 'edit-resource-add', 'value' => $this->cal->gettext('addresource'))) . " " .
         html::tag('input', array('type' => 'button', 'class' => 'button', 'id' => 'edit-resource-find', 'value' => $this->cal->gettext('findresources').'...')))
       );
   }
 
   /**
    *
    */
   function resources_list($attrib = array())
   {
     $attrib += array('id' => 'calendar-resources-list');
 
     $this->rc->output->add_gui_object('resourceslist', $attrib['id']);
 
     return html::tag('ul', $attrib, '', html::$common_attrib);
   }
 
   /**
    *
    */
   public function resource_info($attrib = array())
   {
     $attrib += array('id' => 'calendar-resources-info');
 
     $this->rc->output->add_gui_object('resourceinfo', $attrib['id']);
     $this->rc->output->add_gui_object('resourceownerinfo', $attrib['id'] . '-owner');
 
     // copy address book labels for owner details to client
     $this->rc->output->add_label('name','firstname','surname','department','jobtitle','email','phone','address');
 
     $table_attrib = array('id','class','style','width','summary','cellpadding','cellspacing','border');
 
     return html::tag('table', $attrib,
         html::tag('tbody', null, ''), $table_attrib) .
 
       html::tag('table', array('id' => $attrib['id'] . '-owner', 'style' => 'display:none') + $attrib,
         html::tag('thead', null,
           html::tag('tr', null,
             html::tag('td', array('colspan' => 2), rcube::Q($this->cal->gettext('resourceowner')))
           )
         ) .
         html::tag('tbody', null, ''),
         $table_attrib);
   }
 
   /**
    *
    */
   public function resource_calendar($attrib = array())
   {
     $attrib += array('id' => 'calendar-resources-calendar');
 
     $this->rc->output->add_gui_object('resourceinfocalendar', $attrib['id']);
 
     return html::div($attrib, '');
   }
 
   /**
    * GUI object 'searchform' for the resource finder dialog
    *
    * @param array Named parameters
    * @return string HTML code for the gui object
    */
   function resources_search_form($attrib)
   {
     $attrib += array('command' => 'search-resource', 'id' => 'rcmcalresqsearchbox', 'autocomplete' => 'off');
     $attrib['name'] = '_q';
 
     $input_q = new html_inputfield($attrib);
     $out = $input_q->show();
 
     // add form tag around text field
     $out = $this->rc->output->form_tag(array(
       'name' => "rcmcalresoursqsearchform",
       'onsubmit' => rcmail_output::JS_OBJECT_NAME . ".command('" . $attrib['command'] . "'); return false",
       'style' => "display:inline"),
       $out);
 
     return $out;
   }
 
   /**
    *
    */
   function attendees_freebusy_table($attrib = array())
   {
     $table = new html_table(array('cols' => 2, 'border' => 0, 'cellspacing' => 0));
     $table->add('attendees',
       html::tag('h3', 'boxtitle', $this->cal->gettext('tabattendees')) .
       html::div('timesheader', '&nbsp;') .
       html::div(array('id' => 'schedule-attendees-list', 'class' => 'attendees-list'), '')
     );
     $table->add('times',
       html::div('scroll',
         html::tag('table', array('id' => 'schedule-freebusy-times', 'border' => 0, 'cellspacing' => 0), html::tag('thead') . html::tag('tbody')) .
         html::div(array('id' => 'schedule-event-time', 'style' => 'display:none'), '&nbsp;')
       )
     );
     
     return $table->show($attrib);
   }
 
   /**
    *
    */
   function event_invitebox($attrib = array())
   {
     if ($this->cal->event) {
       return html::div($attrib,
         $this->cal->itip->itip_object_details_table($this->cal->event, $this->cal->itip->gettext('itipinvitation')) .
         $this->cal->invitestatus
       );
     }
     
     return '';
   }
 
   function event_rsvp_buttons($attrib = array())
   {
     $actions = array('accepted','tentative','declined');
     if ($attrib['delegate'] !== 'false')
       $actions[] = 'delegated';
 
     return $this->cal->itip->itip_rsvp_buttons($attrib, $actions);
   }
 
 }
diff --git a/plugins/kolab_addressbook/lib/kolab_addressbook_ui.php b/plugins/kolab_addressbook/lib/kolab_addressbook_ui.php
index 5fab1540..bdfc8887 100644
--- a/plugins/kolab_addressbook/lib/kolab_addressbook_ui.php
+++ b/plugins/kolab_addressbook/lib/kolab_addressbook_ui.php
@@ -1,340 +1,340 @@
 <?php
 
 /**
  * Kolab address book UI
  *
  * @author Aleksander Machniak <machniak@kolabsys.com>
  *
  * Copyright (C) 2012, Kolab Systems AG <contact@kolabsys.com>
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
  * published by the Free Software Foundation, either version 3 of the
  * License, or (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  * GNU Affero General Public License for more details.
  *
  * You should have received a copy of the GNU Affero General Public License
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 class kolab_addressbook_ui
 {
     private $plugin;
     private $rc;
 
     /**
      * Class constructor
      *
      * @param kolab_addressbook $plugin Plugin object
      */
     public function __construct($plugin)
     {
         $this->rc     = rcube::get_instance();
         $this->plugin = $plugin;
 
         $this->init_ui();
     }
 
     /**
      * Adds folders management functionality to Addressbook UI
      */
     private function init_ui()
     {
         if (!empty($this->rc->action) && !preg_match('/^plugin\.book/', $this->rc->action) && $this->rc->action != 'show') {
             return;
         }
 
         // Include script
         $this->plugin->include_script('kolab_addressbook.js');
 
         if (empty($this->rc->action)) {
             // Include stylesheet (for directorylist)
             $this->plugin->include_stylesheet($this->plugin->local_skin_path().'/kolab_addressbook.css');
 
             // include kolab folderlist widget if available
             if (in_array('libkolab', $this->plugin->api->loaded_plugins())) {
                 $this->plugin->api->include_script('libkolab/js/folderlist.js');
             }
 
             // Add actions on address books
             $options = array('book-create', 'book-edit', 'book-delete', 'book-remove');
             $idx     = 0;
 
             if ($this->rc->config->get('kolab_addressbook_carddav_url')) {
               $options[] = 'book-showurl';
               $this->rc->output->set_env('kolab_addressbook_carddav_url', true);
             }
 
             foreach ($options as $command) {
                 $content = html::tag('li', $idx ? null : array('class' => 'separator_above'),
                     $this->plugin->api->output->button(array(
                         'label'    => 'kolab_addressbook.'.str_replace('-', '', $command),
                         'domain'   => $this->ID,
                         'classact' => 'active',
                         'command'  => $command
                 )));
                 $this->plugin->api->add_content($content, 'groupoptions');
                 $idx++;
             }
 
             // Link to Settings/Folders
             $content = html::tag('li', array('class' => 'separator_above'),
                 $this->plugin->api->output->button(array(
                     'label'    => 'managefolders',
                     'type'     => 'link',
                     'classact' => 'active',
                     'command'  => 'folders',
                     'task'     => 'settings',
             )));
             $this->plugin->api->add_content($content, 'groupoptions');
 
             $this->rc->output->add_label('kolab_addressbook.bookdeleteconfirm',
                 'kolab_addressbook.bookdeleting', 'kolab_addressbook.bookshowurl',
                 'kolab_addressbook.carddavurldescription',
                 'kolab_addressbook.bookedit',
                 'kolab_addressbook.bookdelete',
                 'kolab_addressbook.bookshowurl',
                 'kolab_addressbook.findaddressbooks',
                 'kolab_addressbook.searchterms',
                 'kolab_addressbook.foldersearchform',
                 'kolab_addressbook.listsearchresults',
                 'kolab_addressbook.nraddressbooksfound',
                 'kolab_addressbook.noaddressbooksfound',
                 'kolab_addressbook.foldersubscribe',
                 'resetsearch');
 
 
             if ($this->plugin->bonnie_api) {
                 $this->rc->output->set_env('kolab_audit_trail', true);
                 $this->plugin->api->include_script('libkolab/js/audittrail.js');
 
                 $this->rc->output->add_label(
                     'kolab_addressbook.showhistory',
                     'kolab_addressbook.objectchangelog',
                     'kolab_addressbook.objectdiff',
                     'kolab_addressbook.objectdiffnotavailable',
                     'kolab_addressbook.objectchangelognotavailable',
                     'kolab_addressbook.revisionrestoreconfirm'
                 );
 
                 $this->plugin->add_hook('render_page', array($this, 'render_audittrail_page'));
                 $this->plugin->register_handler('plugin.object_changelog_table', array('libkolab', 'object_changelog_table'));
             }
         }
         // include stylesheet for audit trail
         else if ($this->rc->action == 'show' && $this->plugin->bonnie_api) {
             $this->plugin->include_stylesheet($this->plugin->local_skin_path().'/kolab_addressbook.css');
             $this->rc->output->add_label('kolab_addressbook.showhistory');
         }
         // book create/edit form
         else {
             $this->rc->output->add_label('kolab_addressbook.nobooknamewarning',
                 'kolab_addressbook.booksaving');
         }
     }
 
 
     /**
      * Handler for address book create/edit action
      */
     public function book_edit()
     {
         $this->rc->output->add_handler('bookdetails', array($this, 'book_form'));
         $this->rc->output->send('kolab_addressbook.bookedit');
     }
 
 
     /**
      * Handler for 'bookdetails' object returning form content for book create/edit
      *
      * @param array $attr Object attributes
      *
      * @return string HTML output
      */
     public function book_form($attrib)
     {
         $action = trim(rcube_utils::get_input_value('_act', rcube_utils::INPUT_GPC));
         $folder = trim(rcube_utils::get_input_value('_source', rcube_utils::INPUT_GPC, true)); // UTF8
 
         $hidden_fields[] = array('name' => '_source', 'value' => $folder);
 
         $folder  = rcube_charset::convert($folder, RCUBE_CHARSET, 'UTF7-IMAP');
         $storage = $this->rc->get_storage();
         $delim   = $storage->get_hierarchy_delimiter();
 
         if ($this->rc->action == 'plugin.book-save') {
             // save error
             $name      = trim(rcube_utils::get_input_value('_name', rcube_utils::INPUT_GPC, true)); // UTF8
             $old       = trim(rcube_utils::get_input_value('_oldname', rcube_utils::INPUT_GPC, true)); // UTF7-IMAP
             $path_imap = trim(rcube_utils::get_input_value('_parent', rcube_utils::INPUT_GPC, true)); // UTF7-IMAP
 
             $hidden_fields[] = array('name' => '_oldname', 'value' => $old);
 
             $folder = $old;
         }
         else if ($action == 'edit') {
             $path_imap = explode($delim, $folder);
             $name      = rcube_charset::convert(array_pop($path_imap), 'UTF7-IMAP');
             $path_imap = implode($path_imap, $delim);
         }
         else { // create
             $path_imap = $folder;
             $name      = '';
             $folder    = '';
         }
 
         // Store old name, get folder options
         if (strlen($folder)) {
             $hidden_fields[] = array('name' => '_oldname', 'value' => $folder);
 
             $options = $storage->folder_info($folder);
         }
 
         $form   = array();
 
         // General tab
         $form['props'] = array(
             'name' => $this->rc->gettext('properties'),
         );
 
         if (!empty($options) && ($options['norename'] || $options['protected'])) {
             $foldername = rcube::Q(str_replace($delim, ' &raquo; ', kolab_storage::object_name($folder)));
         }
         else {
             $foldername = new html_inputfield(array('name' => '_name', 'id' => '_name', 'size' => 30));
             $foldername = $foldername->show($name);
         }
 
         $form['props']['fieldsets']['location'] = array(
             'name'  => $this->rc->gettext('location'),
             'content' => array(
                 'name' => array(
                     'label' => $this->plugin->gettext('bookname'),
                     'value' => $foldername,
                 ),
             ),
         );
 
         if (!empty($options) && ($options['norename'] || $options['protected'])) {
             // prevent user from moving folder
             $hidden_fields[] = array('name' => '_parent', 'value' => $path_imap);
         }
         else {
             $select = kolab_storage::folder_selector('contact', array('name' => '_parent'), $folder);
 
             $form['props']['fieldsets']['location']['content']['path'] = array(
                 'label' => $this->plugin->gettext('parentbook'),
                 'value' => $select->show(strlen($folder) ? $path_imap : ''),
             );
         }
 
         // Allow plugins to modify address book form content (e.g. with ACL form)
         $plugin = $this->rc->plugins->exec_hook('addressbook_form',
             array('form' => $form, 'options' => $options, 'name' => $folder));
 
         $form = $plugin['form'];
 
         // Set form tags and hidden fields
         list($form_start, $form_end) = $this->get_form_tags($attrib, 'plugin.book-save', null, $hidden_fields);
 
         unset($attrib['form']);
 
         // return the complete edit form as table
         $out = "$form_start\n";
 
         // Create form output
         foreach ($form as $tab) {
             if (!empty($tab['fieldsets']) && is_array($tab['fieldsets'])) {
                 $content = '';
                 foreach ($tab['fieldsets'] as $fieldset) {
                     $subcontent = $this->get_form_part($fieldset);
                     if ($subcontent) {
                         $content .= html::tag('fieldset', null, html::tag('legend', null, rcube::Q($fieldset['name'])) . $subcontent) ."\n";
                     }
                 }
             }
             else {
                 $content = $this->get_form_part($tab);
             }
 
             if ($content) {
                 $out .= html::tag('fieldset', null, html::tag('legend', null, rcube::Q($tab['name'])) . $content) ."\n";
             }
         }
 
         $out .= "\n$form_end";
 
         return $out;
     }
 
     /**
      *
      */
     public function render_audittrail_page($p)
     {
         // append audit trail UI elements to contact page
         if ($p['template'] === 'addressbook' && !$p['kolab-audittrail']) {
             $this->rc->output->add_footer($this->rc->output->parse('kolab_addressbook.audittrail', false, false));
             $p['kolab-audittrail'] = true;
         }
 
         return $p;
     }
 
 
     private function get_form_part($form)
     {
         $content = '';
 
         if (is_array($form['content']) && !empty($form['content'])) {
             $table = new html_table(array('cols' => 2, 'class' => 'propform'));
             foreach ($form['content'] as $col => $colprop) {
                 $colprop['id'] = '_'.$col;
-                $label = !empty($colprop['label']) ? $colprop['label'] : rcube_label($col);
+                $label = !empty($colprop['label']) ? $colprop['label'] : $this->rc->gettext($col);
 
                 $table->add('title', sprintf('<label for="%s">%s</label>', $colprop['id'], rcube::Q($label)));
                 $table->add(null, $colprop['value']);
             }
             $content = $table->show();
         }
         else {
             $content = $form['content'];
         }
 
         return $content;
     }
 
 
     private function get_form_tags($attrib, $action, $id = null, $hidden = null)
     {
         $form_start = $form_end = '';
 
         $request_key = $action . (isset($id) ? '.'.$id : '');
         $form_start = $this->rc->output->request_form(array(
             'name'    => 'form',
             'method'  => 'post',
             'task'    => $this->rc->task,
             'action'  => $action,
             'request' => $request_key,
             'noclose' => true,
         ) + $attrib);
 
         if (is_array($hidden)) {
             foreach ($hidden as $field) {
                 $hiddenfield = new html_hiddenfield($field);
                 $form_start .= $hiddenfield->show();
             }
         }
 
         $form_end = !strlen($attrib['form']) ? '</form>' : '';
 
         $EDIT_FORM = !empty($attrib['form']) ? $attrib['form'] : 'form';
         $this->rc->output->add_gui_object('editform', $EDIT_FORM);
 
         return array($form_start, $form_end);
     }
 
 }
diff --git a/plugins/kolab_addressbook/lib/rcube_kolab_contacts.php b/plugins/kolab_addressbook/lib/rcube_kolab_contacts.php
index c6dfd112..680d7361 100644
--- a/plugins/kolab_addressbook/lib/rcube_kolab_contacts.php
+++ b/plugins/kolab_addressbook/lib/rcube_kolab_contacts.php
@@ -1,1298 +1,1299 @@
 <?php
 
 /**
  * Backend class for a custom address book
  *
  * This part of the Roundcube+Kolab integration and connects the
  * rcube_addressbook interface with the kolab_storage wrapper from libkolab
  *
  * @author Thomas Bruederli <bruederli@kolabsys.com>
  * @author Aleksander Machniak <machniak@kolabsys.com>
  *
  * Copyright (C) 2011, Kolab Systems AG <contact@kolabsys.com>
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
  * published by the Free Software Foundation, either version 3 of the
  * License, or (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  * GNU Affero General Public License for more details.
  *
  * You should have received a copy of the GNU Affero General Public License
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  *
  * @see rcube_addressbook
  */
 class rcube_kolab_contacts extends rcube_addressbook
 {
     public $primary_key = 'ID';
     public $rights   = 'lrs';
     public $readonly = true;
     public $undelete = true;
     public $groups = true;
     public $coltypes = array(
       'name'         => array('limit' => 1),
       'firstname'    => array('limit' => 1),
       'surname'      => array('limit' => 1),
       'middlename'   => array('limit' => 1),
       'prefix'       => array('limit' => 1),
       'suffix'       => array('limit' => 1),
       'nickname'     => array('limit' => 1),
       'jobtitle'     => array('limit' => 1),
       'organization' => array('limit' => 1),
       'department'   => array('limit' => 1),
       'email'        => array('subtypes' => array('home','work','other')),
       'phone'        => array(),
       'address'      => array('subtypes' => array('home','work','office')),
       'website'      => array('subtypes' => array('homepage','blog')),
       'im'           => array('subtypes' => null),
       'gender'       => array('limit' => 1),
       'birthday'     => array('limit' => 1),
       'anniversary'  => array('limit' => 1),
       'profession'   => array('type' => 'text', 'size' => 40, 'maxlength' => 80, 'limit' => 1,
                                 'label' => 'kolab_addressbook.profession', 'category' => 'personal'),
       'manager'      => array('limit' => null),
       'assistant'    => array('limit' => null),
       'spouse'       => array('limit' => 1),
       'children'     => array('type' => 'text', 'size' => 40, 'maxlength' => 80, 'limit' => null,
                                 'label' => 'kolab_addressbook.children', 'category' => 'personal'),
       'freebusyurl'  => array('type' => 'text', 'size' => 40, 'limit' => 1,
                                 'label' => 'kolab_addressbook.freebusyurl'),
       'pgppublickey' => array('type' => 'textarea', 'size' => 70, 'rows' => 10, 'limit' => 1,
                                 'label' => 'kolab_addressbook.pgppublickey'),
       'pkcs7publickey' => array('type' => 'textarea', 'size' => 70, 'rows' => 10, 'limit' => 1,
                                 'label' => 'kolab_addressbook.pkcs7publickey'),
       'notes'        => array('limit' => 1),
       'photo'        => array('limit' => 1),
       // TODO: define more Kolab-specific fields such as: language, latitude, longitude, crypto settings
     );
 
     /**
      * vCard additional fields mapping
      */
     public $vcard_map = array(
       'profession'     => 'X-PROFESSION',
       'officelocation' => 'X-OFFICE-LOCATION',
       'initials'       => 'X-INITIALS',
       'children'       => 'X-CHILDREN',
       'freebusyurl'    => 'X-FREEBUSY-URL',
       'pgppublickey'   => 'KEY',
     );
 
     /**
      * List of date type fields
      */
     public $date_cols = array('birthday', 'anniversary');
 
     private $gid;
     private $storagefolder;
     private $dataset;
     private $sortindex;
     private $contacts;
     private $distlists;
     private $groupmembers;
     private $filter;
     private $result;
     private $namespace;
     private $imap_folder = 'INBOX/Contacts';
     private $action;
 
 
     public function __construct($imap_folder = null)
     {
         if ($imap_folder) {
             $this->imap_folder = $imap_folder;
         }
 
         // extend coltypes configuration 
         $format = kolab_format::factory('contact');
         $this->coltypes['phone']['subtypes'] = array_keys($format->phonetypes);
         $this->coltypes['address']['subtypes'] = array_keys($format->addresstypes);
+        $rcmail = rcmail::get_instance();
 
         // set localized labels for proprietary cols
         foreach ($this->coltypes as $col => $prop) {
             if (is_string($prop['label']))
-                $this->coltypes[$col]['label'] = rcube_label($prop['label']);
+                $this->coltypes[$col]['label'] = $rcmail->gettext($prop['label']);
         }
 
         // fetch objects from the given IMAP folder
         $this->storagefolder = kolab_storage::get_folder($this->imap_folder);
         $this->ready = $this->storagefolder && !PEAR::isError($this->storagefolder);
 
         // Set readonly and rights flags according to folder permissions
         if ($this->ready) {
             if ($this->storagefolder->get_owner() == $_SESSION['username']) {
                 $this->readonly = false;
                 $this->rights = 'lrswikxtea';
             }
             else {
                 $rights = $this->storagefolder->get_myrights();
                 if ($rights && !PEAR::isError($rights)) {
                     $this->rights = $rights;
                     if (strpos($rights, 'i') !== false && strpos($rights, 't') !== false)
                         $this->readonly = false;
                 }
             }
         }
 
         $this->action = rcube::get_instance()->action;
     }
 
 
     /**
      * Getter for the address book name to be displayed
      *
      * @return string Name of this address book
      */
     public function get_name()
     {
         $folder = kolab_storage::object_name($this->imap_folder, $this->namespace);
         return $folder;
     }
 
     /**
      * Wrapper for kolab_storage_folder::get_foldername()
      */
     public function get_foldername()
     {
         return $this->storagefolder->get_foldername();
     }
 
 
     /**
      * Getter for the IMAP folder name
      *
      * @return string Name of the IMAP folder
      */
     public function get_realname()
     {
         return $this->imap_folder;
     }
 
 
     /**
      * Getter for the name of the namespace to which the IMAP folder belongs
      *
      * @return string Name of the namespace (personal, other, shared)
      */
     public function get_namespace()
     {
         if ($this->namespace === null && $this->ready) {
             $this->namespace = $this->storagefolder->get_namespace();
         }
 
         return $this->namespace;
     }
 
     /**
      * Getter for parent folder path
      *
      * @return string Full path to parent folder
      */
     public function get_parent()
     {
         return $this->storagefolder->get_parent();
     }
 
     /**
      * Check subscription status of this folder
      *
      * @return boolean True if subscribed, false if not
      */
     public function is_subscribed()
     {
         return kolab_storage::folder_is_subscribed($this->imap_folder);
     }
 
     /**
      * Compose an URL for CardDAV access to this address book (if configured)
      */
     public function get_carddav_url()
     {
       $rcmail = rcmail::get_instance();
       if ($template = $rcmail->config->get('kolab_addressbook_carddav_url', null)) {
         return strtr($template, array(
           '%h' => $_SERVER['HTTP_HOST'],
           '%u' => urlencode($rcmail->get_user_name()),
           '%i' => urlencode($this->storagefolder->get_uid()),
           '%n' => urlencode($this->imap_folder),
         ));
       }
 
       return false;
     }
 
     /**
      * Setter for the current group
      */
     public function set_group($gid)
     {
         $this->gid = $gid;
     }
 
 
     /**
      * Save a search string for future listings
      *
      * @param mixed Search params to use in listing method, obtained by get_search_set()
      */
     public function set_search_set($filter)
     {
         $this->filter = $filter;
     }
 
 
     /**
      * Getter for saved search properties
      *
      * @return mixed Search properties used by this class
      */
     public function get_search_set()
     {
         return $this->filter;
     }
 
 
     /**
      * Reset saved results and search parameters
      */
     public function reset()
     {
         $this->result = null;
         $this->filter = null;
     }
 
 
     /**
      * List all active contact groups of this source
      *
      * @param string  Optional search string to match group name
      * @return array  Indexed list of contact groups, each a hash array
      */
     function list_groups($search = null)
     {
         $this->_fetch_groups();
         $groups = array();
 
         foreach ((array)$this->distlists as $group) {
             if (!$search || strstr(strtolower($group['name']), strtolower($search)))
                 $groups[$group['name']] = array('ID' => $group['ID'], 'name' => $group['name']);
         }
 
         // sort groups
         ksort($groups, SORT_LOCALE_STRING);
 
         return array_values($groups);
     }
 
 
     /**
      * List the current set of contact records
      *
      * @param array List of cols to show
      * @param  int  Only return this number of records, use negative values for tail
      * @param  boolean True to skip the count query (select only)
      *
      * @return array  Indexed list of contact records, each a hash array
      */
     public function list_records($cols = null, $subset = 0, $nocount = false)
     {
         $this->result = new rcube_result_set(0, ($this->list_page-1) * $this->page_size);
         $fetch_all = false;
 
         // list member of the selected group
         if ($this->gid) {
             $this->_fetch_groups();
 
             $this->sortindex = array();
             $this->contacts  = array();
             $local_sortindex = array();
             $uids            = array();
 
             // get members with email specified
             foreach ((array)$this->distlists[$this->gid]['member'] as $member) {
                 // skip member that don't match the search filter
                 if (!empty($this->filter['ids']) && array_search($member['ID'], $this->filter['ids']) === false) {
                     continue;
                 }
 
                 if (!empty($member['uid'])) {
                     $uids[] = $member['uid'];
                 }
                 else if (!empty($member['email'])) {
                     $this->contacts[$member['ID']] = $member;
                     $local_sortindex[$member['ID']] = $this->_sort_string($member);
                     $fetch_all = true;
                 }
             }
 
             // get members by UID
             if (!empty($uids)) {
                 $this->_fetch_contacts($query = array(array('uid', '=', $uids)), !$fetch_all);
                 $this->sortindex = array_merge($this->sortindex, $local_sortindex);
             }
         }
         else if (is_array($this->filter['ids'])) {
             $ids = $this->filter['ids'];
             if (count($ids)) {
                 $uids = array_map(array($this, 'id2uid'), $this->filter['ids']);
                 $this->_fetch_contacts($query = array(array('uid', '=', $uids)), true);
             }
         }
         else {
             $this->_fetch_contacts($query = 'contact', true);
         }
 
         if ($fetch_all) {
             // sort results (index only)
             asort($this->sortindex, SORT_LOCALE_STRING);
             $ids = array_keys($this->sortindex);
 
             // fill contact data into the current result set
             $this->result->count = count($ids);
             $start_row = $subset < 0 ? $this->result->first + $this->page_size + $subset : $this->result->first;
             $last_row = min($subset != 0 ? $start_row + abs($subset) : $this->result->first + $this->page_size, $this->result->count);
 
             for ($i = $start_row; $i < $last_row; $i++) {
                 if (array_key_exists($i, $ids)) {
                     $idx = $ids[$i];
                     $this->result->add($this->contacts[$idx] ?: $this->_to_rcube_contact($this->dataset[$idx]));
                 }
             }
         }
         else if (!empty($this->dataset)) {
             // get all records count, skip the query if possible
             if (!isset($query) || count($this->dataset) < $this->page_size) {
                 $this->result->count = count($this->dataset) + $this->page_size * ($this->list_page - 1);
             }
             else {
                 $this->result->count = $this->storagefolder->count($query);
             }
 
             $start_row = $subset < 0 ? $this->page_size + $subset : 0;
             $last_row  = min($subset != 0 ? $start_row + abs($subset) : $this->page_size, $this->result->count);
 
             for ($i = $start_row; $i < $last_row; $i++) {
                 $this->result->add($this->_to_rcube_contact($this->dataset[$i]));
             }
         }
 
         return $this->result;
     }
 
 
     /**
      * Search records
      *
      * @param mixed   $fields   The field name of array of field names to search in
      * @param mixed   $value    Search value (or array of values when $fields is array)
      * @param int     $mode     Matching mode:
      *                          0 - partial (*abc*),
      *                          1 - strict (=),
      *                          2 - prefix (abc*)
      * @param boolean $select   True if results are requested, False if count only
      * @param boolean $nocount  True to skip the count query (select only)
      * @param array   $required List of fields that cannot be empty
      *
      * @return object rcube_result_set List of contact records and 'count' value
      */
     public function search($fields, $value, $mode=0, $select=true, $nocount=false, $required=array())
     {
         // search by ID
         if ($fields == $this->primary_key) {
             $ids    = !is_array($value) ? explode(',', $value) : $value;
             $result = new rcube_result_set();
 
             foreach ($ids as $id) {
                 if ($rec = $this->get_record($id, true)) {
                     $result->add($rec);
                     $result->count++;
                 }
             }
             return $result;
         }
         else if ($fields == '*') {
           $fields = array_keys($this->coltypes);
         }
 
         if (!is_array($fields))
             $fields = array($fields);
         if (!is_array($required) && !empty($required))
             $required = array($required);
 
         // advanced search
         if (is_array($value)) {
             $advanced = true;
             $value = array_map('mb_strtolower', $value);
         }
         else
             $value = mb_strtolower($value);
 
         $scount = count($fields);
         // build key name regexp
         $regexp = '/^(' . implode($fields, '|') . ')(?:.*)$/';
 
         // pass query to storage if only indexed cols are involved
         // NOTE: this is only some rough pre-filtering but probably includes false positives
         $squery = $this->_search_query($fields, $value, $mode);
 
         // add magic selector to select contacts with birthday dates only
         if (in_array('birthday', $required)) {
             $squery[] = array('tags', '=', 'x-has-birthday');
         }
 
         // get all/matching records
         $this->_fetch_contacts($squery);
 
         // save searching conditions
         $this->filter = array('fields' => $fields, 'value' => $value, 'mode' => $mode, 'ids' => array());
 
         // search by iterating over all records in dataset
         foreach ($this->dataset as $record) {
             $contact = $this->_to_rcube_contact($record);
             $id = $contact['ID'];
 
             // check if current contact has required values, otherwise skip it
             if ($required) {
                 foreach ($required as $f) {
                     // required field might be 'email', but contact might contain 'email:home'
                     if (!($v = rcube_addressbook::get_col_values($f, $contact, true)) || empty($v)) {
                         continue 2;
                     }
                 }
             }
 
             $found = array();
             $contents = '';
             foreach (preg_grep($regexp, array_keys($contact)) as $col) {
                 $pos     = strpos($col, ':');
                 $colname = $pos ? substr($col, 0, $pos) : $col;
 
                 foreach ((array)$contact[$col] as $val) {
                     if ($advanced) {
                         $found[$colname] = $this->compare_search_value($colname, $val, $value[array_search($colname, $fields)], $mode);
                     }
                     else {
                         $contents .= ' ' . join(' ', (array)$val);
                     }
                 }
             }
 
             // compare matches
             if (($advanced && count($found) >= $scount) ||
                 (!$advanced && rcube_utils::words_match(mb_strtolower($contents), $value))) {
                 $this->filter['ids'][] = $id;
             }
         }
 
         // dummy result with contacts count
         if (!$select) {
             return new rcube_result_set(count($this->filter['ids']), ($this->list_page-1) * $this->page_size);
         }
 
         // list records (now limited by $this->filter)
         return $this->list_records();
     }
 
 
     /**
      * Refresh saved search results after data has changed
      */
     public function refresh_search()
     {
         if ($this->filter)
             $this->search($this->filter['fields'], $this->filter['value'], $this->filter['mode']);
 
         return $this->get_search_set();
     }
 
 
     /**
      * Count number of available contacts in database
      *
      * @return rcube_result_set Result set with values for 'count' and 'first'
      */
     public function count()
     {
         if ($this->gid) {
             $this->_fetch_groups();
             $count = count($this->distlists[$this->gid]['member']);
         }
         else if (is_array($this->filter['ids'])) {
             $count = count($this->filter['ids']);
         }
         else {
             $count = $this->storagefolder->count('contact');
         }
 
         return new rcube_result_set($count, ($this->list_page-1) * $this->page_size);
     }
 
 
     /**
      * Return the last result set
      *
      * @return rcube_result_set Current result set or NULL if nothing selected yet
      */
     public function get_result()
     {
         return $this->result;
     }
 
 
     /**
      * Get a specific contact record
      *
      * @param mixed record identifier(s)
      * @param boolean True to return record as associative array, otherwise a result set is returned
      * @return mixed Result object with all record fields or False if not found
      */
     public function get_record($id, $assoc=false)
     {
         $rec = null;
         $uid = $this->id2uid($id);
         $rev = rcube_utils::get_input_value('_rev', rcube_utils::INPUT_GPC);
 
         if (strpos($uid, 'mailto:') === 0) {
             $this->_fetch_groups(true);
             $rec = $this->contacts[$id];
             $this->readonly = true;  // set source to read-only
         }
         else if (!empty($rev)) {
             $rcmail = rcube::get_instance();
             $plugin = $rcmail->plugins->get_plugin('kolab_addressbook');
             if ($plugin && ($object = $plugin->get_revision($id, kolab_storage::id_encode($this->imap_folder), $rev))) {
                 $rec = $this->_to_rcube_contact($object);
                 $rec['rev'] = $rev;
             }
             $this->readonly = true;  // set source to read-only
         }
         else if ($object = $this->storagefolder->get_object($uid)) {
             $rec = $this->_to_rcube_contact($object);
         }
 
         if ($rec) {
             $this->result = new rcube_result_set(1);
             $this->result->add($rec);
             return $assoc ? $rec : $this->result;
         }
 
         return false;
     }
 
 
     /**
      * Get group assignments of a specific contact record
      *
      * @param mixed Record identifier
      * @return array List of assigned groups as ID=>Name pairs
      */
     public function get_record_groups($id)
     {
         $out = array();
         $this->_fetch_groups();
 
         foreach ((array)$this->groupmembers[$id] as $gid) {
             if ($group = $this->distlists[$gid])
                 $out[$gid] = $group['name'];
         }
 
         return $out;
     }
 
 
     /**
      * Create a new contact record
      *
      * @param array Assoziative array with save data
      *  Keys:   Field name with optional section in the form FIELD:SECTION
      *  Values: Field value. Can be either a string or an array of strings for multiple values
      * @param boolean True to check for duplicates first
      * @return mixed The created record ID on success, False on error
      */
     public function insert($save_data, $check=false)
     {
         if (!is_array($save_data))
             return false;
 
         $insert_id = $existing = false;
 
         // check for existing records by e-mail comparison
         if ($check) {
             foreach ($this->get_col_values('email', $save_data, true) as $email) {
                 if (($res = $this->search('email', $email, true, false)) && $res->count) {
                     $existing = true;
                     break;
                 }
             }
         }
 
         if (!$existing) {
             // remove existing id attributes (#1101)
             unset($save_data['ID'], $save_data['uid']);
 
             // generate new Kolab contact item
             $object = $this->_from_rcube_contact($save_data);
             $saved  = $this->storagefolder->save($object, 'contact');
 
             if (!$saved) {
                 rcube::raise_error(array(
                   'code' => 600, 'type' => 'php',
                   'file' => __FILE__, 'line' => __LINE__,
                   'message' => "Error saving contact object to Kolab server"),
                 true, false);
             }
             else {
                 $insert_id = $this->uid2id($object['uid']);
             }
         }
 
         return $insert_id;
     }
 
 
     /**
      * Update a specific contact record
      *
      * @param mixed Record identifier
      * @param array Assoziative array with save data
      *  Keys:   Field name with optional section in the form FIELD:SECTION
      *  Values: Field value. Can be either a string or an array of strings for multiple values
      * @return boolean True on success, False on error
      */
     public function update($id, $save_data)
     {
         $updated = false;
         if ($old = $this->storagefolder->get_object($this->id2uid($id))) {
             $object = $this->_from_rcube_contact($save_data, $old);
 
             if (!$this->storagefolder->save($object, 'contact', $old['uid'])) {
                 rcube::raise_error(array(
                   'code' => 600, 'type' => 'php',
                   'file' => __FILE__, 'line' => __LINE__,
                   'message' => "Error saving contact object to Kolab server"),
                 true, false);
             }
             else {
                 $updated = true;
 
                 // TODO: update data in groups this contact is member of
             }
         }
 
         return $updated;
     }
 
 
     /**
      * Mark one or more contact records as deleted
      *
      * @param array   Record identifiers
      * @param boolean Remove record(s) irreversible (mark as deleted otherwise)
      *
      * @return int Number of records deleted
      */
     public function delete($ids, $force=true)
     {
         $this->_fetch_groups();
 
         if (!is_array($ids))
             $ids = explode(',', $ids);
 
         $count = 0;
         foreach ($ids as $id) {
             if ($uid = $this->id2uid($id)) {
                 $is_mailto = strpos($uid, 'mailto:') === 0;
                 $deleted = $is_mailto || $this->storagefolder->delete($uid, $force);
 
                 if (!$deleted) {
                     rcube::raise_error(array(
                       'code' => 600, 'type' => 'php',
                       'file' => __FILE__, 'line' => __LINE__,
                       'message' => "Error deleting a contact object $uid from the Kolab server"),
                     true, false);
                 }
                 else {
                     // remove from distribution lists
                     foreach ((array)$this->groupmembers[$id] as $gid) {
                         if (!$is_mailto || $gid == $this->gid)
                             $this->remove_from_group($gid, $id);
                     }
 
                     // clear internal cache
                     unset($this->groupmembers[$id]);
                     $count++;
                 }
             }
         }
 
         return $count;
     }
 
 
     /**
      * Undelete one or more contact records.
      * Only possible just after delete (see 2nd argument of delete() method).
      *
      * @param array  Record identifiers
      *
      * @return int Number of records restored
      */
     public function undelete($ids)
     {
         if (!is_array($ids))
             $ids = explode(',', $ids);
 
         $count = 0;
         foreach ($ids as $id) {
             $uid = $this->id2uid($id);
             if ($this->storagefolder->undelete($uid)) {
                 $count++;
             }
             else {
                 rcube::raise_error(array(
                   'code' => 600, 'type' => 'php',
                   'file' => __FILE__, 'line' => __LINE__,
                   'message' => "Error undeleting a contact object $uid from the Kolab server"),
                 true, false);
             }
         }
 
         return $count;
     }
 
 
     /**
      * Remove all records from the database
      */
     public function delete_all()
     {
         if ($this->storagefolder->delete_all()) {
             $this->contacts = array();
             $this->sortindex = array();
             $this->dataset = null;
             $this->result = null;
         }
     }
 
 
     /**
      * Close connection to source
      * Called on script shutdown
      */
     public function close()
     {
     }
 
 
     /**
      * Create a contact group with the given name
      *
      * @param string The group name
      * @return mixed False on error, array with record props in success
      */
     function create_group($name)
     {
         $this->_fetch_groups();
         $result = false;
 
         $list = array(
             'name' => $name,
             'member' => array(),
         );
         $saved = $this->storagefolder->save($list, 'distribution-list');
 
         if (!$saved) {
             rcube::raise_error(array(
                 'code' => 600, 'type' => 'php',
                 'file' => __FILE__, 'line' => __LINE__,
                 'message' => "Error saving distribution-list object to Kolab server"),
             true, false);
             return false;
         }
         else {
             $id = $this->uid2id($list['uid']);
             $this->distlists[$id] = $list;
             $result = array('id' => $id, 'name' => $name);
         }
 
         return $result;
     }
 
     /**
      * Delete the given group and all linked group members
      *
      * @param string Group identifier
      * @return boolean True on success, false if no data was changed
      */
     function delete_group($gid)
     {
         $this->_fetch_groups();
         $result = false;
 
         if ($list = $this->distlists[$gid]) {
             $deleted = $this->storagefolder->delete($list['uid']);
         }
 
         if (!$deleted) {
             rcube::raise_error(array(
                 'code' => 600, 'type' => 'php',
                 'file' => __FILE__, 'line' => __LINE__,
                 'message' => "Error deleting distribution-list object from the Kolab server"),
             true, false);
         }
         else {
             $result = true;
         }
 
         return $result;
     }
 
     /**
      * Rename a specific contact group
      *
      * @param string Group identifier
      * @param string New name to set for this group
      * @return boolean New name on success, false if no data was changed
      */
     function rename_group($gid, $newname)
     {
         $this->_fetch_groups();
         $list = $this->distlists[$gid];
 
         if ($newname != $list['name']) {
             $list['name'] = $newname;
             $saved = $this->storagefolder->save($list, 'distribution-list', $list['uid']);
         }
 
         if (!$saved) {
             rcube::raise_error(array(
                 'code' => 600, 'type' => 'php',
                 'file' => __FILE__, 'line' => __LINE__,
                 'message' => "Error saving distribution-list object to Kolab server"),
             true, false);
             return false;
         }
 
         return $newname;
     }
 
     /**
      * Add the given contact records the a certain group
      *
      * @param string  Group identifier
      * @param array   List of contact identifiers to be added
      * @return int    Number of contacts added
      */
     function add_to_group($gid, $ids)
     {
         if (!is_array($ids)) {
             $ids = explode(',', $ids);
         }
 
         $this->_fetch_groups(true);
 
         $list   = $this->distlists[$gid];
         $added  = 0;
         $uids   = array();
         $exists = array();
 
         foreach ((array)$list['member'] as $member) {
             $exists[] = $member['ID'];
         }
 
         // substract existing assignments from list
         $ids = array_unique(array_diff($ids, $exists));
 
         // add mailto: members
         foreach ($ids as $contact_id) {
             $uid = $this->id2uid($contact_id);
             if (strpos($uid, 'mailto:') === 0 && ($contact = $this->contacts[$contact_id])) {
                 $list['member'][] = array(
                     'email' => $contact['email'],
                     'name'  => $contact['name'],
                 );
                 $this->groupmembers[$contact_id][] = $gid;
                 $added++;
             }
             else {
                 $uids[$uid] = $contact_id;
             }
         }
 
         // add members with UID
         if (!empty($uids)) {
             foreach ($uids as $uid => $contact_id) {
                 $list['member'][] = array('uid' => $uid);
                 $this->groupmembers[$contact_id][] = $gid;
                 $added++;
             }
         }
 
         if ($added)
             $saved = $this->storagefolder->save($list, 'distribution-list', $list['uid']);
         else
             $saved = true;
 
         if (!$saved) {
             rcube::raise_error(array(
                 'code' => 600, 'type' => 'php',
                 'file' => __FILE__, 'line' => __LINE__,
                 'message' => "Error saving distribution-list to Kolab server"),
             true, false);
             $added = false;
             $this->set_error(self::ERROR_SAVING, 'errorsaving');
         }
         else {
             $this->distlists[$gid] = $list;
         }
 
         return $added;
     }
 
     /**
      * Remove the given contact records from a certain group
      *
      * @param string  Group identifier
      * @param array   List of contact identifiers to be removed
      * @return int    Number of deleted group members
      */
     function remove_from_group($gid, $ids)
     {
         if (!is_array($ids))
             $ids = explode(',', $ids);
 
         $this->_fetch_groups();
         if (!($list = $this->distlists[$gid]))
             return false;
 
         $new_member = array();
         foreach ((array)$list['member'] as $member) {
             if (!in_array($member['ID'], $ids))
                 $new_member[] = $member;
         }
 
         // write distribution list back to server
         $list['member'] = $new_member;
         $saved = $this->storagefolder->save($list, 'distribution-list', $list['uid']);
 
         if (!$saved) {
             rcube::raise_error(array(
                 'code' => 600, 'type' => 'php',
                 'file' => __FILE__, 'line' => __LINE__,
                 'message' => "Error saving distribution-list object to Kolab server"),
             true, false);
         }
         else {
             // remove group assigments in local cache
             foreach ($ids as $id) {
                 $j = array_search($gid, $this->groupmembers[$id]);
                 unset($this->groupmembers[$id][$j]);
             }
             $this->distlists[$gid] = $list;
             return true;
         }
 
         return false;
     }
 
     /**
      * Check the given data before saving.
      * If input not valid, the message to display can be fetched using get_error()
      *
      * @param array Associative array with contact data to save
      *
      * @return boolean True if input is valid, False if not.
      */
     public function validate(&$save_data)
     {
         // validate e-mail addresses
         $valid = parent::validate($save_data);
 
         // require at least one e-mail address if there's no name
         // (syntax check is already done)
         if ($valid) {
             if (!strlen($save_data['name'])
                 && !strlen($save_data['organization'])
                 && !array_filter($this->get_col_values('email', $save_data, true))
             ) {
                 $this->set_error('warning', 'kolab_addressbook.noemailnamewarning');
                 $valid = false;
             }
         }
 
         return $valid;
     }
 
     /**
      * Query storage layer and store records in private member var
      */
     private function _fetch_contacts($query = array(), $limit = false)
     {
         if (!isset($this->dataset) || !empty($query)) {
             if ($limit) {
                 $this->storagefolder->set_order_and_limit($this->_sort_columns(), $this->page_size, ($this->list_page-1) * $this->page_size);
             }
             $this->sortindex = array();
             $this->dataset = $this->storagefolder->select($query);
             foreach ($this->dataset as $idx => $record) {
                 $contact = $this->_to_rcube_contact($record);
                 $this->sortindex[$idx] = $this->_sort_string($contact);
             }
         }
     }
 
     /**
      * Extract a string for sorting from the given contact record
      */
     private function _sort_string($rec)
     {
         $str = '';
 
         switch ($this->sort_col) {
         case 'name':
             $str = $rec['name'] . $rec['prefix'];
         case 'firstname':
             $str .= $rec['firstname'] . $rec['middlename'] . $rec['surname'];
             break;
 
         case 'surname':
             $str = $rec['surname'] . $rec['firstname'] . $rec['middlename'];
             break;
 
         default:
             $str = $rec[$this->sort_col];
             break;
         }
 
         $str .= is_array($rec['email']) ? $rec['email'][0] : $rec['email'];
         return mb_strtolower($str);
     }
 
     /**
      * Return the cache table columns to order by
      */
     private function _sort_columns()
     {
         $sortcols = array();
 
         switch ($this->sort_col) {
         case 'name':
             $sortcols[] = 'name';
         case 'firstname':
             $sortcols[] = 'firstname';
             break;
 
         case 'surname':
             $sortcols[] = 'surname';
             break;
         }
 
         $sortcols[] = 'email';
         return $sortcols;
     }
 
     /**
      * Read distribution-lists AKA groups from server
      */
     private function _fetch_groups($with_contacts = false)
     {
         if (!isset($this->distlists)) {
             $this->distlists = $this->groupmembers = array();
             foreach ($this->storagefolder->get_objects('distribution-list') as $record) {
                 $record['ID'] = $this->uid2id($record['uid']);
                 foreach ((array)$record['member'] as $i => $member) {
                     $mid = $this->uid2id($member['uid'] ? $member['uid'] : 'mailto:' . $member['email']);
                     $record['member'][$i]['ID'] = $mid;
                     $record['member'][$i]['readonly'] = empty($member['uid']);
                     $this->groupmembers[$mid][] = $record['ID'];
 
                     if ($with_contacts && empty($member['uid']))
                         $this->contacts[$mid] = $record['member'][$i];
                 }
                 $this->distlists[$record['ID']] = $record;
             }
         }
     }
 
     /**
      * Encode object UID into a safe identifier
      */
     public function uid2id($uid)
     {
         return rtrim(strtr(base64_encode($uid), '+/', '-_'), '=');
     }
 
     /**
      * Convert Roundcube object identifier back into the original UID
      */
     public function id2uid($id)
     {
         return base64_decode(str_pad(strtr($id, '-_', '+/'), strlen($id) % 4, '=', STR_PAD_RIGHT));
     }
 
     /**
      * Build SQL query for fulltext matches
      */
     private function _search_query($fields, $value, $mode)
     {
         $query = array();
         $cols  = array();
 
         // $fulltext_cols might contain composite field names e.g. 'email:address' while $fields not
         foreach (kolab_format_contact::$fulltext_cols as $col) {
             if ($pos = strpos($col, ':')) {
                 $col = substr($col, 0, $pos);
             }
             if (in_array($col, $fields)) {
                 $cols[] = $col;
             }
         }
 
         if (count($cols) == count($fields)) {
             switch ($mode) {
                 case 1:  $prefix = '^'; $suffix = '$'; break;  // strict
                 case 2:  $prefix = '^'; $suffix = '';  break;  // prefix
                 default: $prefix = '';  $suffix = '';  break;  // substring
             }
 
             $search_string = is_array($value) ? join(' ', $value) : $value;
             foreach (rcube_utils::normalize_string($search_string, true) as $word) {
                 $query[] = array('words', 'LIKE', $prefix . $word . $suffix);
             }
         }
 
         return $query;
     }
 
     /**
      * Map fields from internal Kolab_Format to Roundcube contact format
      */
     private function _to_rcube_contact($record)
     {
         $record['ID'] = $this->uid2id($record['uid']);
 
         // convert email, website, phone values
         foreach (array('email'=>'address', 'website'=>'url', 'phone'=>'number') as $col => $propname) {
             if (is_array($record[$col])) {
                 $values = $record[$col];
                 unset($record[$col]);
                 foreach ((array)$values as $i => $val) {
                     $key = $col . ($val['type'] ? ':' . $val['type'] : '');
                     $record[$key][] = $val[$propname];
                 }
             }
         }
 
         if (is_array($record['address'])) {
             $addresses = $record['address'];
             unset($record['address']);
             foreach ($addresses as $i => $adr) {
                 $key = 'address' . ($adr['type'] ? ':' . $adr['type'] : '');
                 $record[$key][] = array(
                     'street'   => $adr['street'],
                     'locality' => $adr['locality'],
                     'zipcode'  => $adr['code'],
                     'region'   => $adr['region'],
                     'country'  => $adr['country'],
                 );
             }
         }
 
         // photo is stored as separate attachment
         if ($record['photo'] && strlen($record['photo']) < 255 && ($att = $record['_attachments'][$record['photo']])) {
             // only fetch photo content if requested
             if ($this->action == 'photo')
                 $record['photo'] = $att['content'] ? $att['content'] : $this->storagefolder->get_attachment($record['uid'], $att['id']);
         }
 
         // truncate publickey value for display
         if ($record['pgppublickey'] && $this->action == 'show')
             $record['pgppublickey'] = substr($record['pgppublickey'], 0, 140) . '...';
 
         // remove empty fields
         $record = array_filter($record);
 
         // remove kolab_storage internal data
         unset($record['_msguid'], $record['_formatobj'], $record['_mailbox'], $record['_type'], $record['_size']);
 
         return $record;
     }
 
     /**
      * Map fields from Roundcube format to internal kolab_format_contact properties
      */
     private function _from_rcube_contact($contact, $old = array())
     {
         if (!$contact['uid'] && $contact['ID'])
             $contact['uid'] = $this->id2uid($contact['ID']);
         else if (!$contact['uid'] && $old['uid'])
             $contact['uid'] = $old['uid'];
 
         $contact['im'] = array_filter($this->get_col_values('im', $contact, true));
 
         // convert email, website, phone values
         foreach (array('email'=>'address', 'website'=>'url', 'phone'=>'number') as $col => $propname) {
             $col_values = $this->get_col_values($col, $contact);
             $contact[$col] = array();
             foreach ($col_values as $type => $values) {
                 foreach ((array)$values as $val) {
                     if (!empty($val)) {
                         $contact[$col][] = array($propname => $val, 'type' => $type);
                     }
                 }
                 unset($contact[$col.':'.$type]);
             }
         }
 
         $addresses = array();
         foreach ($this->get_col_values('address', $contact) as $type => $values) {
             foreach ((array)$values as $adr) {
                 // skip empty address
                 $adr = array_filter($adr);
                 if (empty($adr))
                     continue;
 
                 $addresses[] = array(
                     'type' => $type,
                     'street' => $adr['street'],
                     'locality' => $adr['locality'],
                     'code' => $adr['zipcode'],
                     'region' => $adr['region'],
                     'country' => $adr['country'],
                 );
             }
 
             unset($contact['address:'.$type]);
         }
 
         $contact['address'] = $addresses;
 
         // categories are not supported in the web client but should be preserved (#2608)
         $contact['categories'] = $old['categories'];
 
         // copy meta data (starting with _) from old object
         foreach ((array)$old as $key => $val) {
             if (!isset($contact[$key]) && $key[0] == '_')
                 $contact[$key] = $val;
         }
 
         // convert one-item-array elements into string element
         // this is needed e.g. to properly import birthday field
         foreach ($this->coltypes as $type => $col_def) {
             if ($col_def['limit'] == 1 && is_array($contact[$type])) {
                 $contact[$type] = array_shift(array_filter($contact[$type]));
             }
         }
 
         // When importing contacts 'vcard' data is added, we don't need it (Bug #1711)
         unset($contact['vcard']);
 
         // add empty values for some fields which can be removed in the UI
         return array_filter($contact) + array('nickname' => '', 'birthday' => '', 'anniversary' => '', 'freebusyurl' => '', 'photo' => $contact['photo']);
     }
 
 }
diff --git a/plugins/libcalendaring/lib/libcalendaring_itip.php b/plugins/libcalendaring/lib/libcalendaring_itip.php
index d00e0990..a36f27cc 100644
--- a/plugins/libcalendaring/lib/libcalendaring_itip.php
+++ b/plugins/libcalendaring/lib/libcalendaring_itip.php
@@ -1,817 +1,817 @@
 <?php
 
 /**
  * iTIP functions for the calendar-based Roudncube plugins
  *
  * Class providing functionality to manage iTIP invitations
  *
  * @author Thomas Bruederli <bruederli@kolabsys.com>
  *
  * Copyright (C) 2011-2014, Kolab Systems AG <contact@kolabsys.com>
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
  * published by the Free Software Foundation, either version 3 of the
  * License, or (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  * GNU Affero General Public License for more details.
  *
  * You should have received a copy of the GNU Affero General Public License
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 class libcalendaring_itip
 {
     protected $rc;
     protected $lib;
     protected $plugin;
     protected $sender;
     protected $domain;
     protected $itip_send = false;
     protected $rsvp_actions = array('accepted','tentative','declined','delegated');
     protected $rsvp_status  = array('accepted','tentative','declined','delegated');
 
     function __construct($plugin, $domain = 'libcalendaring')
     {
         $this->plugin = $plugin;
         $this->rc = rcube::get_instance();
         $this->lib = libcalendaring::get_instance();
         $this->domain = $domain;
 
         $hook = $this->rc->plugins->exec_hook('calendar_load_itip',
             array('identity' => $this->rc->user->list_emails(true)));
         $this->sender = $hook['identity'];
 
         $this->plugin->add_hook('message_before_send', array($this, 'before_send_hook'));
         $this->plugin->add_hook('smtp_connect', array($this, 'smtp_connect_hook'));
     }
 
     public function set_sender_email($email)
     {
         if (!empty($email))
             $this->sender['email'] = $email;
     }
 
     public function set_rsvp_actions($actions)
     {
         $this->rsvp_actions = (array)$actions;
         $this->rsvp_status = array_merge($this->rsvp_actions, array('delegated'));
     }
 
     public function set_rsvp_status($status)
     {
         $this->rsvp_status = $status;
     }
 
     /**
      * Wrapper for rcube_plugin::gettext()
      * Checking for a label in different domains
      *
      * @see rcube::gettext()
      */
     public function gettext($p)
     {
         $label = is_array($p) ? $p['name'] : $p;
         $domain = $this->domain;
         if (!$this->rc->text_exists($label, $domain)) {
             $domain = 'libcalendaring';
         }
         return $this->rc->gettext($p, $domain);
     }
 
     /**
      * Send an iTip mail message
      *
      * @param array   Event object to send
      * @param string  iTip method (REQUEST|REPLY|CANCEL)
      * @param array   Hash array with recipient data (name, email)
      * @param string  Mail subject
      * @param string  Mail body text label
      * @param object  Mail_mime object with message data
      * @param boolean Request RSVP
      * @return boolean True on success, false on failure
      */
     public function send_itip_message($event, $method, $recipient, $subject, $bodytext, $message = null, $rsvp = true)
     {
         if (!$this->sender['name'])
             $this->sender['name'] = $this->sender['email'];
 
         if (!$message) {
             libcalendaring::identify_recurrence_instance($event);
             $message = $this->compose_itip_message($event, $method, $rsvp);
         }
 
         $mailto = rcube_utils::idn_to_ascii($recipient['email']);
 
         $headers = $message->headers();
         $headers['To'] = format_email_recipient($mailto, $recipient['name']);
         $headers['Subject'] = $this->gettext(array(
             'name' => $subject,
             'vars' => array(
                 'title' => $event['title'],
                 'name' => $this->sender['name']
             )
         ));
 
         // compose a list of all event attendees
         $attendees_list = array();
         foreach ((array)$event['attendees'] as $attendee) {
             $attendees_list[] = ($attendee['name'] && $attendee['email']) ?
                 $attendee['name'] . ' <' . $attendee['email'] . '>' :
                 ($attendee['name'] ? $attendee['name'] : $attendee['email']);
         }
 
         $recurrence_info = '';
         if (!empty($event['recurrence_id'])) {
             $recurrence_info = "\n\n** " . $this->gettext($event['thisandfuture'] ? 'itipmessagefutureoccurrence' : 'itipmessagesingleoccurrence') . ' **';
         }
         else if (!empty($event['recurrence'])) {
             $recurrence_info = sprintf("\n%s: %s", $this->gettext('recurring'), $this->lib->recurrence_text($event['recurrence']));
         }
 
         $mailbody = $this->gettext(array(
             'name' => $bodytext,
             'vars' => array(
                 'title' => $event['title'],
                 'date' => $this->lib->event_date_text($event, true) . $recurrence_info,
                 'attendees' => join(",\n ", $attendees_list),
                 'sender' => $this->sender['name'],
                 'organizer' => $this->sender['name'],
             )
         ));
 
         // if (!empty($event['comment'])) {
         //     $mailbody .= "\n\n" . $this->gettext('itipsendercomment') . $event['comment'];
         // }
 
         // append links for direct invitation replies
         if ($method == 'REQUEST' && $rsvp && ($token = $this->store_invitation($event, $recipient['email']))) {
             $mailbody .= "\n\n" . $this->gettext(array(
                 'name' => 'invitationattendlinks',
                 'vars' => array('url' => $this->plugin->get_url(array('action' => 'attend', 't' => $token))),
             ));
         }
         else if ($method == 'CANCEL' && $event['cancelled']) {
             $this->cancel_itip_invitation($event);
         }
 
         $message->headers($headers, true);
         $message->setTXTBody(rcube_mime::format_flowed($mailbody, 79));
 
         if ($this->rc->config->get('libcalendaring_itip_debug', false)) {
             console('iTip ' . $method, $message->txtHeaders() . "\n\r" . $message->get());
         }
 
         // finally send the message
         $this->itip_send = true;
         $sent = $this->rc->deliver_message($message, $headers['X-Sender'], $mailto, $smtp_error);
         $this->itip_send = false;
 
         return $sent;
     }
 
     /**
      * Plugin hook triggered by rcube::deliver_message() before delivering a message.
      * Here we can set the 'smtp_server' config option to '' in order to use
      * PHP's mail() function for unauthenticated email sending.
      */
     public function before_send_hook($p)
     {
         if ($this->itip_send && !$this->rc->user->ID && $this->rc->config->get('calendar_itip_smtp_server', null) === '') {
             $this->rc->config->set('smtp_server', '');
         }
 
         return $p;
     }
 
     /**
      * Plugin hook to alter SMTP authentication.
      * This is used if iTip messages are to be sent from an unauthenticated session
      */
     public function smtp_connect_hook($p)
     {
         // replace smtp auth settings if we're not in an authenticated session
         if ($this->itip_send && !$this->rc->user->ID) {
             foreach (array('smtp_server', 'smtp_user', 'smtp_pass') as $prop) {
                 $p[$prop] = $this->rc->config->get("calendar_itip_$prop", $p[$prop]);
             }
         }
 
       return $p;
     }
 
     /**
      * Helper function to build a Mail_mime object to send an iTip message
      *
      * @param array   Event object to send
      * @param string  iTip method (REQUEST|REPLY|CANCEL)
      * @param boolean Request RSVP
      * @return object Mail_mime object with message data
      */
     public function compose_itip_message($event, $method, $rsvp = true)
     {
         $from     = rcube_utils::idn_to_ascii($this->sender['email']);
         $from_utf = rcube_utils::idn_to_utf8($from);
         $sender   = format_email_recipient($from, $this->sender['name']);
 
         // truncate list attendees down to the recipient of the iTip Reply.
         // constraints for a METHOD:REPLY according to RFC 5546
         if ($method == 'REPLY') {
             $replying_attendee = null;
             $reply_attendees = array();
             foreach ($event['attendees'] as $attendee) {
                 if ($attendee['role'] == 'ORGANIZER') {
                     $reply_attendees[] = $attendee;
                 }
                 else if (strcasecmp($attendee['email'], $from) == 0 || strcasecmp($attendee['email'], $from_utf) == 0) {
                     $replying_attendee = $attendee;
                     if ($attendee['status'] != 'DELEGATED') {
                         unset($replying_attendee['rsvp']);  // unset the RSVP attribute
                     }
                 }
                 // include attendees relevant for delegation (RFC 5546, Section 4.2.5)
                 else if ((!empty($attendee['delegated-to']) &&
                             (strcasecmp($attendee['delegated-to'], $from) == 0 || strcasecmp($attendee['delegated-to'], $from_utf) == 0)) ||
                          (!empty($attendee['delegated-from']) &&
                             (strcasecmp($attendee['delegated-from'], $from) == 0 || strcasecmp($attendee['delegated-from'], $from_utf) == 0))) {
                     $reply_attendees[] = $attendee;
                 }
             }
             if ($replying_attendee) {
                 array_unshift($reply_attendees, $replying_attendee);
                 $event['attendees'] = $reply_attendees;
             }
             if ($event['recurrence']) {
                 unset($event['recurrence']['EXCEPTIONS']);
             }
         }
         // set RSVP for every attendee
         else if ($method == 'REQUEST') {
             foreach ($event['attendees'] as $i => $attendee) {
                 if (($rsvp || !isset($attendee['rsvp'])) && ($attendee['status'] != 'DELEGATED' && $attendee['role'] != 'NON-PARTICIPANT')) {
                     $event['attendees'][$i]['rsvp']= (bool)$rsvp;
                 }
             }
         }
         else if ($method == 'CANCEL') {
             if ($event['recurrence']) {
                 unset($event['recurrence']['EXCEPTIONS']);
             }
         }
 
         // compose multipart message using PEAR:Mail_Mime
         $message = new Mail_mime("\r\n");
         $message->setParam('text_encoding', 'quoted-printable');
         $message->setParam('head_encoding', 'quoted-printable');
         $message->setParam('head_charset', RCUBE_CHARSET);
         $message->setParam('text_charset', RCUBE_CHARSET . ";\r\n format=flowed");
         $message->setContentType('multipart/alternative');
 
         // compose common headers array
         $headers = array(
             'From' => $sender,
             'Date' => $this->rc->user_date(),
             'Message-ID' => $this->rc->gen_message_id(),
             'X-Sender' => $from,
         );
         if ($agent = $this->rc->config->get('useragent')) {
             $headers['User-Agent'] = $agent;
         }
 
         $message->headers($headers);
 
         // attach ics file for this event
         $ical = libcalendaring::get_ical();
         $ics = $ical->export(array($event), $method, false, $method == 'REQUEST' && $this->plugin->driver ? array($this->plugin->driver, 'get_attachment_body') : false);
         $filename = $event['_type'] == 'task' ? 'todo.ics' : 'event.ics';
         $message->addAttachment($ics, 'text/calendar', $filename, false, '8bit', '', RCUBE_CHARSET . "; method=" . $method);
 
         return $message;
     }
 
     /**
      * Forward the given iTip event as delegation to another person
      *
      * @param array Event object to delegate
      * @param mixed Delegatee as string or hash array with keys 'name' and 'mailto'
      * @param boolean The delegator's RSVP flag
      * @param array List with indexes of new/updated attendees
      * @return boolean True on success, False on failure
      */
     public function delegate_to(&$event, $delegate, $rsvp = false, &$attendees = array())
     {
         if (is_string($delegate)) {
             $delegates = rcube_mime::decode_address_list($delegate, 1, false);
             if (count($delegates) > 0) {
                 $delegate = reset($delegates);
             }
         }
 
         $emails = $this->lib->get_user_emails();
         $me     = $this->rc->user->list_emails(true);
 
         // find/create the delegate attendee
         $delegate_attendee = array(
             'email' => $delegate['mailto'],
             'name'  => $delegate['name'],
             'role'  => 'REQ-PARTICIPANT',
         );
         $delegate_index = count($event['attendees']);
 
         foreach ($event['attendees'] as $i => $attendee) {
           // set myself the DELEGATED-TO parameter
           if ($attendee['email'] && in_array(strtolower($attendee['email']), $emails)) {
               $event['attendees'][$i]['delegated-to'] = $delegate['mailto'];
               $event['attendees'][$i]['status'] = 'DELEGATED';
               $event['attendees'][$i]['role'] = 'NON-PARTICIPANT';
               $event['attendees'][$i]['rsvp'] = $rsvp;
 
               $me['email'] = $attendee['email'];
               $delegate_attendee['role'] = $attendee['role'];
           }
           // the disired delegatee is already listed as an attendee
           else if (stripos($delegate['mailto'], $attendee['email']) !== false && $attendee['role'] != 'ORGANIZER') {
               $delegate_attendee = $attendee;
               $delegate_index = $i;
               break;
           }
           // TODO: remove previous delegatee (i.e. attendee that has DELEGATED-FROM == $me)
         }
 
         // set/add delegate attendee with RSVP=TRUE and DELEGATED-FROM parameter
         $delegate_attendee['rsvp'] = true;
         $delegate_attendee['status'] = 'NEEDS-ACTION';
         $delegate_attendee['delegated-from'] = $me['email'];
         $event['attendees'][$delegate_index] = $delegate_attendee;
 
         $attendees[] = $delegate_index;
 
         $this->set_sender_email($me['email']);
         return $this->send_itip_message($event, 'REQUEST', $delegate_attendee, 'itipsubjectdelegatedto', 'itipmailbodydelegatedto');
     }
 
     /**
      * Handler for calendar/itip-status requests
      */
     public function get_itip_status($event, $existing = null)
     {
       $action = $event['rsvp'] ? 'rsvp' : '';
       $status = $event['fallback'];
       $latest = false;
       $html = '';
 
       if (is_numeric($event['changed']))
         $event['changed'] = new DateTime('@'.$event['changed']);
 
       // check if the given itip object matches the last state
       if ($existing) {
         $latest = (isset($event['sequence']) && intval($existing['sequence']) == intval($event['sequence'])) ||
                   (!isset($event['sequence']) && $existing['changed'] && $existing['changed'] >= $event['changed']);
       }
 
       // determine action for REQUEST
       if ($event['method'] == 'REQUEST') {
         $html = html::div('rsvp-status', $this->gettext('acceptinvitation'));
 
         if ($existing) {
           $rsvp = $event['rsvp'];
           $emails = $this->lib->get_user_emails();
           foreach ($existing['attendees'] as $attendee) {
             if ($attendee['email'] && in_array(strtolower($attendee['email']), $emails)) {
               $status = strtoupper($attendee['status']);
               break;
             }
           }
         }
         else {
           $rsvp = $event['rsvp'] && $this->rc->config->get('calendar_allow_itip_uninvited', true);
         }
 
         $status_lc = strtolower($status);
 
         if ($status_lc == 'unknown' && !$this->rc->config->get('calendar_allow_itip_uninvited', true)) {
           $html = html::div('rsvp-status', $this->gettext('notanattendee'));
           $action = 'import';
         }
         else if (in_array($status_lc, $this->rsvp_status)) {
           $status_text = $this->gettext(($latest ? 'youhave' : 'youhavepreviously') . $status_lc);
 
           if ($existing && ($existing['sequence'] > $event['sequence'] || (!isset($event['sequence']) && $existing['changed'] && $existing['changed'] > $event['changed']))) {
             $action = '';  // nothing to do here, outdated invitation
             if ($status_lc == 'needs-action')
               $status_text = $this->gettext('outdatedinvitation');
           }
           else if (!$existing && !$rsvp) {
             $action = 'import';
           }
           else if ($latest && $status_lc != 'needs-action') {
             $action = 'update';
           }
 
           $html = html::div('rsvp-status ' . $status_lc, $status_text);
         }
       }
       // determine action for REPLY
       else if ($event['method'] == 'REPLY') {
         // check whether the sender already is an attendee
         if ($existing) {
           $action = $this->rc->config->get('calendar_allow_itip_uninvited', true) ? 'accept' : '';
           $listed = false;
           foreach ($existing['attendees'] as $attendee) {
             if ($attendee['role'] != 'ORGANIZER' && strcasecmp($attendee['email'], $event['attendee']) == 0) {
               $status_lc = strtolower($status);
               if (in_array($status_lc, $this->rsvp_status)) {
                 $html = html::div('rsvp-status ' . $status_lc, $this->gettext(array(
                     'name' => 'attendee' . $status_lc,
                     'vars' => array(
                         'delegatedto' => rcube::Q($event['delegated-to'] ?: ($attendee['delegated-to'] ?: '?')),
                     )
                 )));
               }
               $action = $attendee['status'] == $status || !$latest ? '' : 'update';
               $listed = true;
               break;
             }
           }
 
           if (!$listed) {
             $html = html::div('rsvp-status', $this->gettext('itipnewattendee'));
           }
         }
         else {
           $html = html::div('rsvp-status hint', $this->gettext('itipobjectnotfound'));
           $action = '';
         }
       }
       else if ($event['method'] == 'CANCEL') {
         if (!$existing) {
           $html = html::div('rsvp-status hint', $this->gettext('itipobjectnotfound'));
           $action = '';
         }
       }
 
       return array(
           'uid' => $event['uid'],
           'id' => asciiwords($event['uid'], true),
           'existing' => $existing ? true : false,
           'saved' => $existing ? true : false,
           'latest' => $latest,
           'status' => $status,
           'action' => $action,
           'html' => $html,
       );
     }
 
     /**
      * Build inline UI elements for iTip messages
      */
     public function mail_itip_inline_ui($event, $method, $mime_id, $task, $message_date = null, $preview_url = null)
     {
         $buttons = array();
         $dom_id = asciiwords($event['uid'], true);
         $rsvp_status = 'unknown';
 
         // pass some metadata about the event and trigger the asynchronous status check
         $changed = is_object($event['changed']) ? $event['changed'] : $message_date;
         $metadata = array(
             'uid'      => $event['uid'],
             '_instance' => $event['_instance'],
             'changed'  => $changed ? $changed->format('U') : 0,
             'sequence' => intval($event['sequence']),
             'method'   => $method,
             'task'     => $task,
         );
 
         // create buttons to be activated from async request checking existence of this event in local calendars
         $buttons[] = html::div(array('id' => 'loading-'.$dom_id, 'class' => 'rsvp-status loading'), $this->gettext('loading'));
 
         // on iTip REPLY we have two options:
         if ($method == 'REPLY') {
             $title = $this->gettext('itipreply');
 
             foreach ($event['attendees'] as $attendee) {
                 if (!empty($attendee['email']) && $attendee['role'] != 'ORGANIZER' &&
                       (empty($event['_sender']) || ($attendee['email'] == $event['_sender'] || $attendee['email'] == $event['_sender_utf']))) {
                     $metadata['attendee'] = $attendee['email'];
                     $rsvp_status = strtoupper($attendee['status']);
                     if ($attendee['delegated-to'])
                         $metadata['delegated-to'] = $attendee['delegated-to'];
                     break;
                 }
             }
 
             // 1. update the attendee status on our copy
             $update_button = html::tag('input', array(
                 'type' => 'button',
                 'class' => 'button',
                 'onclick' => "rcube_libcalendaring.add_from_itip_mail('" . rcube::JQ($mime_id) . "', '$task')",
                 'value' => $this->gettext('updateattendeestatus'),
             ));
 
             // 2. accept or decline a new or delegate attendee
             $accept_buttons = html::tag('input', array(
                 'type' => 'button',
                 'class' => "button accept",
                 'onclick' => "rcube_libcalendaring.add_from_itip_mail('" . rcube::JQ($mime_id) . "', '$task')",
                 'value' => $this->gettext('acceptattendee'),
             ));
             $accept_buttons .= html::tag('input', array(
                 'type' => 'button',
                 'class' => "button decline",
                 'onclick' => "rcube_libcalendaring.decline_attendee_reply('" . rcube::JQ($mime_id) . "', '$task')",
                 'value' => $this->gettext('declineattendee'),
             ));
 
             $buttons[] = html::div(array('id' => 'update-'.$dom_id, 'style' => 'display:none'), $update_button);
             $buttons[] = html::div(array('id' => 'accept-'.$dom_id, 'style' => 'display:none'), $accept_buttons);
         }
         // when receiving iTip REQUEST messages:
         else if ($method == 'REQUEST') {
             $emails = $this->lib->get_user_emails();
             $title = $event['sequence'] > 0 ? $this->gettext('itipupdate') : $this->gettext('itipinvitation');
             $metadata['rsvp'] = true;
             $metadata['sensitivity'] = $event['sensitivity'];
 
             if (is_object($event['start'])) {
                 $metadata['date'] = $event['start']->format('U');
             }
 
             // check for X-KOLAB-INVITATIONTYPE property and only show accept/decline buttons
             if (self::get_custom_property($event, 'X-KOLAB-INVITATIONTYPE') == 'CONFIRMATION') {
                 $this->rsvp_actions = array('accepted','declined');
                 $metadata['nosave'] = true;
             }
 
             // 1. display RSVP buttons (if the user was invited)
             foreach ($this->rsvp_actions as $method) {
                 $rsvp_buttons .= html::tag('input', array(
                     'type' => 'button',
                     'class' => "button $method",
                     'onclick' => "rcube_libcalendaring.add_from_itip_mail('" . rcube::JQ($mime_id) . "', '$task', '$method', '$dom_id')",
                     'value' => $this->gettext('itip' . $method),
                 ));
             }
 
             // add button to open calendar/preview
             if (!empty($preview_url)) {
               $msgref = $this->lib->ical_message->folder . '/' . $this->lib->ical_message->uid . '#' . $mime_id;
               $rsvp_buttons .= html::tag('input', array(
                   'type' => 'button',
                   'class' => "button preview",
                   'onclick' => "rcube_libcalendaring.open_itip_preview('" . rcube::JQ($preview_url) . "', '" . rcube::JQ($msgref) . "')",
                   'value' => $this->gettext('openpreview'),
               ));
             }
 
             // 2. update the local copy with minor changes
             $update_button = html::tag('input', array(
                 'type' => 'button',
                 'class' => 'button',
                 'onclick' => "rcube_libcalendaring.add_from_itip_mail('" . rcube::JQ($mime_id) . "', '$task')",
                 'value' => $this->gettext('updatemycopy'),
             ));
 
             // 3. Simply import the event without replying
             $import_button = html::tag('input', array(
                 'type' => 'button',
                 'class' => 'button',
                 'onclick' => "rcube_libcalendaring.add_from_itip_mail('" . rcube::JQ($mime_id) . "', '$task')",
                 'value' => $this->gettext('importtocalendar'),
             ));
 
             // check my status
             foreach ($event['attendees'] as $attendee) {
                 if ($attendee['email'] && in_array(strtolower($attendee['email']), $emails)) {
                     $metadata['attendee'] = $attendee['email'];
                     $metadata['rsvp'] = $attendee['rsvp'] || $attendee['role'] != 'NON-PARTICIPANT';
                     $rsvp_status = !empty($attendee['status']) ? strtoupper($attendee['status']) : 'NEEDS-ACTION';
                     break;
                 }
             }
 
             // add itip reply message controls
             $rsvp_buttons .= html::div('itip-reply-controls', $this->itip_rsvp_options_ui($dom_id, $metadata['nosave']));
 
             $buttons[] = html::div(array('id' => 'rsvp-'.$dom_id, 'class' => 'rsvp-buttons', 'style' => 'display:none'), $rsvp_buttons);
             $buttons[] = html::div(array('id' => 'update-'.$dom_id, 'style' => 'display:none'), $update_button);
 
             // prepare autocompletion for delegation dialog
             if (in_array('delegated', $this->rsvp_actions)) {
                 $this->rc->autocomplete_init();
             }
         }
         // for CANCEL messages, we can:
         else if ($method == 'CANCEL') {
             $title = $this->gettext('itipcancellation');
             $event_prop = array_filter(array(
               'uid' => $event['uid'],
               '_instance' => $event['_instance'],
               '_savemode' => $event['_savemode'],
             ));
 
             // 1. remove the event from our calendar
             $button_remove = html::tag('input', array(
                 'type' => 'button',
                 'class' => 'button',
                 'onclick' => "rcube_libcalendaring.remove_from_itip(" . rcube_output::json_serialize($event_prop) . ", '$task', '" . rcube::JQ($event['title']) . "')",
                 'value' => $this->gettext('removefromcalendar'),
             ));
 
             // 2. update our copy with status=cancelled
             $button_update = html::tag('input', array(
               'type' => 'button',
               'class' => 'button',
               'onclick' => "rcube_libcalendaring.add_from_itip_mail('" . rcube::JQ($mime_id) . "', '$task')",
               'value' => $this->gettext('updatemycopy'),
             ));
 
             $buttons[] = html::div(array('id' => 'rsvp-'.$dom_id, 'style' => 'display:none'), $button_remove . $button_update);
 
             $rsvp_status = 'CANCELLED';
             $metadata['rsvp'] = true;
         }
 
         // append generic import button
         if ($import_button) {
             $buttons[] = html::div(array('id' => 'import-'.$dom_id, 'style' => 'display:none'), $import_button);
         }
 
         // pass some metadata about the event and trigger the asynchronous status check
         $metadata['fallback'] = $rsvp_status;
         $metadata['rsvp'] = intval($metadata['rsvp']);
 
-        $this->rc->output->add_script("rcube_libcalendaring.fetch_itip_object_status(" . json_serialize($metadata) . ")", 'docready');
+        $this->rc->output->add_script("rcube_libcalendaring.fetch_itip_object_status(" . rcube_output::json_serialize($metadata) . ")", 'docready');
 
         // get localized texts from the right domain
         foreach (array('savingdata','deleteobjectconfirm','declinedeleteconfirm','declineattendee',
             'cancel','itipdelegated','declineattendeeconfirm','itipcomment','delegateinvitation',
             'delegateto','delegatersvpme','delegateinvalidaddress') as $label) {
           $this->rc->output->command('add_label', "itip.$label", $this->gettext($label));
         }
 
         // show event details with buttons
         return $this->itip_object_details_table($event, $title) .
             html::div(array('class' => 'itip-buttons', 'id' => 'itip-buttons-' . asciiwords($metadata['uid'], true)), join('', $buttons));
     }
 
     /**
      * Render an RSVP UI widget with buttons to respond on iTip invitations
      */
     function itip_rsvp_buttons($attrib = array(), $actions = null)
     {
         $attrib += array('type' => 'button');
 
         if (!$actions)
             $actions = $this->rsvp_actions;
 
         foreach ($actions as $method) {
             $buttons .= html::tag('input', array(
                 'type'  => $attrib['type'],
                 'name'  => $attrib['iname'],
                 'class' => 'button',
                 'rel'   => $method,
                 'value' => $this->gettext('itip' . $method),
             ));
         }
 
         // add localized texts for the delegation dialog
         if (in_array('delegated', $actions)) {
             foreach (array('itipdelegated','itipcomment','delegateinvitation',
                   'delegateto','delegatersvpme','delegateinvalidaddress','cancel') as $label) {
                 $this->rc->output->command('add_label', "itip.$label", $this->gettext($label));
             }
         }
 
         foreach (array('all','current','future') as $mode) {
             $this->rc->output->command('add_label', "rsvpmode$mode", $this->gettext("rsvpmode$mode"));
         }
 
         $savemode_radio = new html_radiobutton(array('name' => '_rsvpmode', 'class' => 'rsvp-replymode'));
 
         return html::div($attrib,
             html::div('label', $this->gettext('acceptinvitation')) .
             html::div('rsvp-buttons',
                 $buttons .
                 html::div('itip-reply-controls', $this->itip_rsvp_options_ui($attrib['id']))
             )
         );
     }
 
     /**
      * Render UI elements to control iTip reply message sending
      */
     public function itip_rsvp_options_ui($dom_id, $disable = false)
     {
         $itip_sending = $this->rc->config->get('calendar_itip_send_option', 3);
 
         // itip sending is entirely disabled
         if ($itip_sending === 0) {
             return '';
         }
         // add checkbox to suppress itip reply message
         else if ($itip_sending >= 2) {
             $rsvp_additions = html::label(array('class' => 'noreply-toggle'),
                 html::tag('input', array('type' => 'checkbox', 'id' => 'noreply-'.$dom_id, 'value' => 1, 'disabled' => $disable, 'checked' => ($itip_sending & 1) == 0))
                 . ' ' . $this->gettext('itipsuppressreply')
             );
         }
 
         // add input field for reply comment
         $rsvp_additions .= html::a(array('href' => '#toggle', 'class' => 'reply-comment-toggle'), $this->gettext('itipeditresponse'));
         $rsvp_additions .= html::div('itip-reply-comment',
             html::tag('textarea', array('id' => 'reply-comment-'.$dom_id, 'name' => '_comment', 'cols' => 40, 'rows' => 6, 'style' => 'display:none', 'placeholder' => $this->gettext('itipcomment')), '')
         );
 
         return $rsvp_additions;
     }
 
     /**
      * Render event/task details in a table
      */
     function itip_object_details_table($event, $title)
     {
         $table = new html_table(array('cols' => 2, 'border' => 0, 'class' => 'calendar-eventdetails'));
         $table->add('ititle', $title);
         $table->add('title', rcube::Q($event['title']));
         if ($event['start'] && $event['end']) {
             $table->add('label', $this->gettext('date'));
             $table->add('date', rcube::Q($this->lib->event_date_text($event)));
         }
         else if ($event['due'] && $event['_type'] == 'task') {
             $table->add('label', $this->gettext('date'));
             $table->add('date', rcube::Q($this->lib->event_date_text($event)));
         }
         if (!empty($event['recurrence_date'])) {
             $table->add('label', '');
             $table->add('recurrence-id', $this->gettext($event['thisandfuture'] ? 'itipfutureoccurrence' : 'itipsingleoccurrence'));
         }
         else if (!empty($event['recurrence'])) {
             $table->add('label', $this->gettext('recurring'));
             $table->add('recurrence', $this->lib->recurrence_text($event['recurrence']));
         }
         if ($event['location']) {
             $table->add('label', $this->gettext('location'));
             $table->add('location', rcube::Q($event['location']));
         }
         if ($event['sensitivity'] && $event['sensitivity'] != 'public') {
             $table->add('label', $this->gettext('sensitivity'));
             $table->add('sensitivity', ucfirst($this->gettext($event['sensitivity'])) . '!');
         }
         if ($event['status'] == 'COMPLETED' || $event['status'] == 'CANCELLED') {
             $table->add('label', $this->gettext('status'));
             $table->add('status', $this->gettext('status-' . strtolower($event['status'])));
         }
         if ($event['comment']) {
             $table->add('label', $this->gettext('comment'));
             $table->add('location', rcube::Q($event['comment']));
         }
 
         return $table->show();
     }
 
 
     /**
      * Create iTIP invitation token for later replies via URL
      *
      * @param array Hash array with event properties
      * @param string Attendee email address
      * @return string Invitation token
      */
     public function store_invitation($event, $attendee)
     {
         // empty stub
         return false;
     }
 
     /**
      * Mark invitations for the given event as cancelled
      *
      * @param array Hash array with event properties
      */
     public function cancel_itip_invitation($event)
     {
         // empty stub
         return false;
     }
 
     /**
      * Utility function to get the value of a custom property
      */
     public static function get_custom_property($event, $name)
     {
       $ret = false;
 
       if (is_array($event['x-custom'])) {
           array_walk($event['x-custom'], function($prop, $i) use ($name, &$ret) {
               if (strcasecmp($prop[0], $name) === 0) {
                   $ret = $prop[1];
               }
           });
       }
 
       return $ret;
     }
 
 }
diff --git a/plugins/tasklist/tasklist_ui.php b/plugins/tasklist/tasklist_ui.php
index d89defc4..2a18713f 100644
--- a/plugins/tasklist/tasklist_ui.php
+++ b/plugins/tasklist/tasklist_ui.php
@@ -1,541 +1,541 @@
 <?php
 /**
  * User Interface class for the Tasklist plugin
  *
  * @version @package_version@
  * @author Thomas Bruederli <bruederli@kolabsys.com>
  *
  * Copyright (C) 2012-2015, Kolab Systems AG <contact@kolabsys.com>
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
  * published by the Free Software Foundation, either version 3 of the
  * License, or (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  * GNU Affero General Public License for more details.
  *
  * You should have received a copy of the GNU Affero General Public License
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 
 
 class tasklist_ui
 {
     private $rc;
     private $plugin;
     private $ready = false;
     private $gui_objects = array();
 
     function __construct($plugin)
     {
         $this->plugin = $plugin;
         $this->rc     = $plugin->rc;
     }
 
     /**
      * Calendar UI initialization and requests handlers
      */
     public function init()
     {
         if ($this->ready) {
             return;
         }
 
         // add taskbar button
         $this->plugin->add_button(array(
             'command'    => 'tasks',
             'class'      => 'button-tasklist',
             'classsel'   => 'button-tasklist button-selected',
             'innerclass' => 'button-inner',
             'label'      => 'tasklist.navtitle',
         ), 'taskbar');
 
         $this->plugin->include_stylesheet($this->plugin->local_skin_path() . '/tasklist.css');
 
         if ($this->rc->task == 'mail' || $this->rc->task == 'tasks') {
             jqueryui::tagedit();
 
             $this->plugin->include_script('tasklist_base.js');
 
             // copy config to client
             $this->rc->output->set_env('tasklist_settings', $this->load_settings());
 
             // initialize attendees autocompletion
             $this->rc->autocomplete_init();
         }
 
         $this->ready = true;
     }
 
     /**
      *
      */
     function load_settings()
     {
         $settings = array();
 
         $settings['invite_shared'] = (int)$this->rc->config->get('calendar_allow_invite_shared', 0);
         $settings['itip_notify']   = (int)$this->rc->config->get('calendar_itip_send_option', 3);
         $settings['sort_col']      = $this->rc->config->get('tasklist_sort_col', '');
         $settings['sort_order']    = $this->rc->config->get('tasklist_sort_order', 'asc');
 
         // get user identity to create default attendee
         foreach ($this->rc->user->list_emails() as $rec) {
             if (!$identity)
                 $identity = $rec;
 
             $identity['emails'][] = $rec['email'];
             $settings['identities'][$rec['identity_id']] = $rec['email'];
         }
 
         $identity['emails'][] = $this->rc->user->get_username();
         $settings['identity'] = array(
             'name'   => $identity['name'],
             'email'  => strtolower($identity['email']),
             'emails' => ';' . strtolower(join(';', $identity['emails']))
         );
 
         if ($list = rcube_utils::get_input_value('_list', rcube_utils::INPUT_GPC)) {
             $settings['selected_list'] = $list;
         }
         if ($list && ($id = rcube_utils::get_input_value('_id', rcube_utils::INPUT_GPC))) {
             $settings['selected_id'] = $id;
 
             // check if the referenced task is completed
             $task = $this->plugin->driver->get_task(array('id' => $id, 'list' => $list));
             if ($task && $this->plugin->driver->is_complete($task)) {
                 $settings['selected_filter'] = 'complete';
             }
         }
         else if ($filter = rcube_utils::get_input_value('_filter', rcube_utils::INPUT_GPC)) {
             $settings['selected_filter'] = $filter;
         }
 
         return $settings;
     }
 
     /**
      * Render a HTML select box for user identity selection
      */
     function identity_select($attrib = array())
     {
         $attrib['name'] = 'identity';
         $select         = new html_select($attrib);
         $identities     = $this->rc->user->list_emails();
 
         foreach ($identities as $ident) {
             $select->add(format_email_recipient($ident['email'], $ident['name']), $ident['identity_id']);
         }
 
         return $select->show(null);
     }
 
     /**
     * Register handler methods for the template engine
     */
     public function init_templates()
     {
         $this->plugin->register_handler('plugin.tasklists', array($this, 'tasklists'));
         $this->plugin->register_handler('plugin.tasklist_select', array($this, 'tasklist_select'));
         $this->plugin->register_handler('plugin.status_select', array($this, 'status_select'));
         $this->plugin->register_handler('plugin.searchform', array($this->rc->output, 'search_form'));
         $this->plugin->register_handler('plugin.quickaddform', array($this, 'quickadd_form'));
         $this->plugin->register_handler('plugin.tasks', array($this, 'tasks_resultview'));
         $this->plugin->register_handler('plugin.tagslist', array($this, 'tagslist'));
         $this->plugin->register_handler('plugin.tags_editline', array($this, 'tags_editline'));
         $this->plugin->register_handler('plugin.alarm_select', array($this, 'alarm_select'));
         $this->plugin->register_handler('plugin.recurrence_form', array($this->plugin->lib, 'recurrence_form'));
         $this->plugin->register_handler('plugin.attachments_form', array($this, 'attachments_form'));
         $this->plugin->register_handler('plugin.attachments_list', array($this, 'attachments_list'));
         $this->plugin->register_handler('plugin.filedroparea', array($this, 'file_drop_area'));
         $this->plugin->register_handler('plugin.attendees_list', array($this, 'attendees_list'));
         $this->plugin->register_handler('plugin.attendees_form', array($this, 'attendees_form'));
         $this->plugin->register_handler('plugin.identity_select', array($this, 'identity_select'));
         $this->plugin->register_handler('plugin.edit_attendees_notify', array($this, 'edit_attendees_notify'));
         $this->plugin->register_handler('plugin.task_rsvp_buttons', array($this->plugin->itip, 'itip_rsvp_buttons'));
         $this->plugin->register_handler('plugin.object_changelog_table', array('libkolab', 'object_changelog_table'));
 
         jqueryui::tagedit();
 
         $this->plugin->include_script('tasklist.js');
         $this->rc->output->include_script('treelist.js');
 
         // include kolab folderlist widget if available
         if (in_array('libkolab', $this->plugin->api->loaded_plugins())) {
             $this->plugin->api->include_script('libkolab/js/folderlist.js');
             $this->plugin->api->include_script('libkolab/js/audittrail.js');
         }
     }
 
     /**
      *
      */
     public function tasklists($attrib = array())
     {
         $tree = true;
         $jsenv = array();
         $lists = $this->plugin->driver->get_lists($tree);
 
         // walk folder tree
         if (is_object($tree)) {
             $html = $this->list_tree_html($tree, $lists, $jsenv, $attrib);
         }
         else {
             // fall-back to flat folder listing
             $attrib['class'] .= ' flat';
 
             $html = '';
             foreach ((array)$lists as $id => $prop) {
                 if ($attrib['activeonly'] && !$prop['active'])
                   continue;
 
                 $html .= html::tag('li', array(
                         'id' => 'rcmlitasklist' . rcube_utils::html_identifier($id),
                         'class' => $prop['group'],
                     ),
                     $this->tasklist_list_item($id, $prop, $jsenv, $attrib['activeonly'])
                 );
             }
         }
 
         $this->rc->output->set_env('tasklists', $jsenv);
         $this->register_gui_object('tasklistslist', $attrib['id']);
 
         return html::tag('ul', $attrib, $html, html::$common_attrib);
     }
 
     /**
      * Return html for a structured list <ul> for the folder tree
      */
     public function list_tree_html($node, $data, &$jsenv, $attrib)
     {
         $out = '';
         foreach ($node->children as $folder) {
             $id = $folder->id;
             $prop = $data[$id];
             $is_collapsed = false; // TODO: determine this somehow?
 
             $content = $this->tasklist_list_item($id, $prop, $jsenv, $attrib['activeonly']);
 
             if (!empty($folder->children)) {
                 $content .= html::tag('ul', array('style' => ($is_collapsed ? "display:none;" : null)),
                     $this->list_tree_html($folder, $data, $jsenv, $attrib));
             }
 
             if (strlen($content)) {
                 $out .= html::tag('li', array(
                       'id' => 'rcmlitasklist' . rcube_utils::html_identifier($id),
                       'class' => $prop['group'] . ($prop['virtual'] ? ' virtual' : ''),
                     ),
                     $content);
             }
         }
 
         return $out;
     }
 
     /**
      * Helper method to build a tasklist item (HTML content and js data)
      */
     public function tasklist_list_item($id, $prop, &$jsenv, $activeonly = false)
     {
         // enrich list properties with settings from the driver
         if (!$prop['virtual']) {
             unset($prop['user_id']);
             $prop['alarms']      = $this->plugin->driver->alarms;
             $prop['undelete']    = $this->plugin->driver->undelete;
             $prop['sortable']    = $this->plugin->driver->sortable;
             $prop['attachments'] = $this->plugin->driver->attachments;
             $prop['attendees']   = $this->plugin->driver->attendees;
             $prop['caldavurl']   = $this->plugin->driver->tasklist_caldav_url($prop);
             $jsenv[$id] = $prop;
         }
 
         $classes = array('tasklist');
         $title = $prop['title'] ?: ($prop['name'] != $prop['listname'] || strlen($prop['name']) > 25 ?
           html_entity_decode($prop['name'], ENT_COMPAT, RCUBE_CHARSET) : '');
 
         if ($prop['virtual'])
             $classes[] = 'virtual';
         else if (!$prop['editable'])
             $classes[] = 'readonly';
         if ($prop['subscribed'])
             $classes[] = 'subscribed';
         if ($prop['class'])
             $classes[] = $prop['class'];
 
         if (!$activeonly || $prop['active']) {
             $label_id = 'tl:' . $id;
             return html::div(join(' ', $classes),
                 html::span(array('class' => 'listname', 'title' => $title, 'id' => $label_id), $prop['listname'] ?: $prop['name']) .
                   ($prop['virtual'] ? '' :
                       html::tag('input', array('type' => 'checkbox', 'name' => '_list[]', 'value' => $id, 'checked' => $prop['active'], 'aria-labelledby' => $label_id)) .
                       html::span('actions', 
                           ($prop['removable'] ? html::a(array('href' => '#', 'class' => 'remove', 'title' => $this->plugin->gettext('removelist')), ' ') : '') .
                           html::a(array('href' => '#', 'class' => 'quickview', 'title' => $this->plugin->gettext('focusview'), 'role' => 'checkbox', 'aria-checked' => 'false'), ' ') .
                           (isset($prop['subscribed']) ? html::a(array('href' => '#', 'class' => 'subscribed', 'title' => $this->plugin->gettext('tasklistsubscribe'), 'role' => 'checkbox', 'aria-checked' => $prop['subscribed'] ? 'true' : 'false'), ' ') : '')
                       )
                 )
             );
         }
 
         return '';
     }
 
     /**
      * Render HTML form for task status selector
      */
     function status_select($attrib = array())
     {
         $attrib['name'] = 'status';
         $select = new html_select($attrib);
         $select->add('---', '');
         $select->add($this->plugin->gettext('status-needs-action'), 'NEEDS-ACTION');
         $select->add($this->plugin->gettext('status-in-process'),   'IN-PROCESS');
         $select->add($this->plugin->gettext('status-completed'),    'COMPLETED');
         $select->add($this->plugin->gettext('status-cancelled'),    'CANCELLED');
 
         return $select->show(null);
     }
 
     /**
      * Render a HTML select box for list selection
      */
     function tasklist_select($attrib = array())
     {
         $attrib['name']       = 'list';
         $attrib['is_escaped'] = true;
         $select = new html_select($attrib);
         $default = null;
 
         foreach ((array)$this->plugin->driver->get_lists() as $id => $prop) {
             if ($prop['editable'] || strpos($prop['rights'], 'i') !== false) {
                 $select->add($prop['name'], $id);
                 if (!$default || $prop['default'])
                     $default = $id;
             }
         }
 
         return $select->show($default);
     }
 
 
     function tasklist_editform($action, $list = array())
     {
         $fields = array(
             'name' => array(
                 'id' => 'taskedit-tasklistame',
                 'label' => $this->plugin->gettext('listname'),
                 'value' => html::tag('input', array('id' => 'taskedit-tasklistame', 'name' => 'name', 'type' => 'text', 'class' => 'text', 'size' => 40)),
             ),
 /*
             'color' => array(
                 'id' => 'taskedit-color',
                 'label' => $this->plugin->gettext('color'),
                 'value' => html::tag('input', array('id' => 'taskedit-color', 'name' => 'color', 'type' => 'text', 'class' => 'text colorpicker', 'size' => 6)),
             ),
 */
             'showalarms' => array(
                 'id' => 'taskedit-showalarms',
                 'label' => $this->plugin->gettext('showalarms'),
                 'value' => html::tag('input', array('id' => 'taskedit-showalarms', 'name' => 'color', 'type' => 'checkbox')),
             ),
         );
 
         return html::tag('form', array('action' => "#", 'method' => "post", 'id' => 'tasklisteditform'),
             $this->plugin->driver->tasklist_edit_form($action, $list, $fields)
         );
     }
 
     /**
      * Render HTML form for alarm configuration
      */
     function alarm_select($attrib = array())
     {
         $attrib['_type'] = 'task';
         return $this->plugin->lib->alarm_select($attrib, $this->plugin->driver->alarm_types, $this->plugin->driver->alarm_absolute);
     }
 
     /**
      *
      */
     function quickadd_form($attrib)
     {
         $attrib += array('action' => $this->rc->url('add'), 'method' => 'post', 'id' => 'quickaddform');
 
         $label = html::label(array('for' => 'quickaddinput', 'class' => 'voice'), $this->plugin->gettext('quickaddinput'));
         $input = new html_inputfield(array('name' => 'text', 'id' => 'quickaddinput'));
         $button = html::tag('input', array('type' => 'submit', 'value' => '+', 'title' => $this->plugin->gettext('createtask'), 'class' => 'button mainaction'));
 
         $this->register_gui_object('quickaddform', $attrib['id']);
         return html::tag('form', $attrib, $label . $input->show() . $button);
     }
 
     /**
      * The result view
      */
     function tasks_resultview($attrib)
     {
         $attrib += array('id' => 'rcmtaskslist');
 
         $this->register_gui_object('resultlist', $attrib['id']);
 
         unset($attrib['name']);
         return html::tag('ul', $attrib, '');
     }
 
     /**
      * Container for a tags cloud
      */
     function tagslist($attrib)
     {
         $attrib += array('id' => 'rcmtasktagslist');
         unset($attrib['name']);
 
         $this->register_gui_object('tagslist', $attrib['id']);
         return html::tag('ul', $attrib, '');
     }
 
     /**
      * Interactive UI element to add/remove tags
      */
     function tags_editline($attrib)
     {
         $attrib += array('id' => 'rcmtasktagsedit');
         $this->register_gui_object('edittagline', $attrib['id']);
 
         $input = new html_inputfield(array('name' => 'tags[]', 'class' => 'tag', 'size' => $attrib['size'], 'tabindex' => $attrib['tabindex']));
         unset($attrib['tabindex']);
         return html::div($attrib, $input->show(''));
     }
 
     /**
      * Generate HTML element for attachments list
      */
     function attachments_list($attrib = array())
     {
         if (!$attrib['id'])
             $attrib['id'] = 'rcmtaskattachmentlist';
 
         $this->register_gui_object('attachmentlist', $attrib['id']);
 
         return html::tag('ul', $attrib, '', html::$common_attrib);
     }
 
     /**
      * Generate the form for event attachments upload
      */
     function attachments_form($attrib = array())
     {
         // add ID if not given
         if (!$attrib['id'])
             $attrib['id'] = 'rcmtaskuploadform';
 
         // Get max filesize, enable upload progress bar
-        $max_filesize = rcube_upload_init();
+        $max_filesize = $this->rc->upload_init();
 
         $button = new html_inputfield(array('type' => 'button'));
         $input = new html_inputfield(array(
             'type' => 'file',
             'name' => '_attachments[]',
             'multiple' => 'multiple',
             'size' => $attrib['attachmentfieldsize'],
         ));
 
         return html::div($attrib,
             html::div(null, $input->show()) .
             html::div('formbuttons', $button->show($this->rc->gettext('upload'), array('class' => 'button mainaction',
                 'onclick' => rcmail_output::JS_OBJECT_NAME . ".upload_file(this.form)"))) .
             html::div('hint', $this->rc->gettext(array('name' => 'maxuploadsize', 'vars' => array('size' => $max_filesize))))
         );
     }
 
     /**
      * Register UI object for HTML5 drag & drop file upload
      */
     function file_drop_area($attrib = array())
     {
         if ($attrib['id']) {
             $this->register_gui_object('filedrop', $attrib['id']);
             $this->rc->output->set_env('filedrop', array('action' => 'upload', 'fieldname' => '_attachments'));
         }
     }
 
     /**
      *
      */
     function attendees_list($attrib = array())
     {
         // add "noreply" checkbox to attendees table only
         $invitations = strpos($attrib['id'], 'attend') !== false;
 
         $invite = new html_checkbox(array('value' => 1, 'id' => 'edit-attendees-invite'));
         $table  = new html_table(array('cols' => 4 + intval($invitations), 'border' => 0, 'cellpadding' => 0, 'class' => 'rectable'));
 
 //      $table->add_header('role', $this->plugin->gettext('role'));
         $table->add_header('name', $this->plugin->gettext($attrib['coltitle'] ?: 'attendee'));
         $table->add_header('confirmstate', $this->plugin->gettext('confirmstate'));
         if ($invitations) {
             $table->add_header(array('class' => 'invite', 'title' => $this->plugin->gettext('sendinvitations')),
                 $invite->show(1) . html::label('edit-attendees-invite', $this->plugin->gettext('sendinvitations')));
         }
         $table->add_header('options', '');
 
         // hide invite column if disabled by config
         $itip_notify = (int)$this->rc->config->get('calendar_itip_send_option', 3);
         if ($invitations && !($itip_notify & 2)) {
             $css = sprintf('#%s td.invite, #%s th.invite { display:none !important }', $attrib['id'], $attrib['id']);
             $this->rc->output->add_footer(html::tag('style', array('type' => 'text/css'), $css));
         }
 
         return $table->show($attrib);
     }
 
     /**
      *
      */
     function attendees_form($attrib = array())
     {
         $input    = new html_inputfield(array('name' => 'participant', 'id' => 'edit-attendee-name', 'size' => 30));
         $textarea = new html_textarea(array('name' => 'comment', 'id' => 'edit-attendees-comment',
             'rows' => 4, 'cols' => 55, 'title' => $this->plugin->gettext('itipcommenttitle')));
 
         return html::div($attrib,
             html::div(null, $input->show() . " " .
                 html::tag('input', array('type' => 'button', 'class' => 'button', 'id' => 'edit-attendee-add', 'value' => $this->plugin->gettext('addattendee')))
                 // . " " . html::tag('input', array('type' => 'button', 'class' => 'button', 'id' => 'edit-attendee-schedule', 'value' => $this->plugin->gettext('scheduletime').'...'))
                 ) .
             html::p('attendees-commentbox', html::label(null, $this->plugin->gettext('itipcomment') . $textarea->show()))
         );
     }
 
     /**
      *
      */
     function edit_attendees_notify($attrib = array())
     {
         $checkbox = new html_checkbox(array('name' => '_notify', 'id' => 'edit-attendees-donotify', 'value' => 1));
         return html::div($attrib, html::label(null, $checkbox->show(1) . ' ' . $this->plugin->gettext('sendnotifications')));
     }
 
     /**
      * Wrapper for rcube_output_html::add_gui_object()
      */
     function register_gui_object($name, $id)
     {
         $this->gui_objects[$name] = $id;
         $this->rc->output->add_gui_object($name, $id);
     }
 
     /**
      * Getter for registered gui objects.
      * (for manual registration when loading the inline UI)
      */
     function get_gui_objects()
     {
         return $this->gui_objects;
     }
 }