diff --git a/plugins/calendar/calendar.php b/plugins/calendar/calendar.php
index 4ed5023c..afb23854 100644
--- a/plugins/calendar/calendar.php
+++ b/plugins/calendar/calendar.php
@@ -1,3611 +1,3606 @@
 <?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,
   );
 
 // These are implemented with __get()
 //  private $ical;
 //  private $itip;
 //  private $driver;
 
 
   /**
    * Plugin initialization.
    */
   function init()
   {
     $this->rc = rcube::get_instance();
 
     $this->register_task('calendar', 'calendar');
 
     // load calendar configuration
     $this->load_config();
 
     // 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 if ($this->rc->task != 'login') {
       // default startup routine
       $this->add_hook('startup', array($this, 'startup'));
     }
 
     $this->add_hook('user_delete', array($this, 'user_delete'));
   }
 
   /**
    * Setup basic plugin environment and UI
    */
   protected function setup()
   {
     $this->require_plugin('libcalendaring');
     $this->require_plugin('libkolab');
 
     $this->lib             = libcalendaring::get_instance();
     $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;
 
     // load localizations
     $this->add_texts('localization/', $this->rc->task == 'calendar' && (!$this->rc->action || $this->rc->action == 'print'));
 
     require($this->home . '/lib/calendar_ui.php');
     $this->ui = new calendar_ui($this);
   }
 
   /**
    * 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;
 
     $this->setup();
 
     // 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'));
       $this->register_action('dialog-ui', array($this, 'mail_message2event'));
       $this->register_action('check-recent', array($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' && $_GET['_rel'] != 'event') {
         $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, $calendars = null)
   {
     if ($calendars === null) {
       $calendars = $this->driver->list_calendars(calendar_driver::FILTER_PERSONAL | calendar_driver::FILTER_WRITEABLE);
     }
 
     $default_id = $this->rc->config->get('calendar_default_calendar');
     $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 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');
 
     // initialize attendees autocompletion
     $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('identities-selector', $this->ui->identity_select(array(
         'id'         => 'edit-identities-list',
         'aria-label' => $this->gettext('roleorganizer'),
         'class'      => 'form-control custom-select',
     )));
 
     $view = rcube_utils::get_input_value('view', rcube_utils::INPUT_GPC);
     if (in_array($view, array('agendaWeek', 'agendaDay', 'month', 'list')))
       $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';
       $view = $this->rc->config->get('calendar_default_view', $this->defaults['calendar_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'), "list");
       $p['blocks']['view']['options']['default_view'] = array(
         'title' => html::label($field_id, rcube::Q($this->gettext('default_view'))),
         'content' => $select->show($view == 'table' ? 'list' : $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));
       $select->add($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';
       $work_start = $this->rc->config->get('calendar_work_start', $this->defaults['calendar_work_start']);
       $work_end   = $this->rc->config->get('calendar_work_end', $this->defaults['calendar_work_end']);
       $p['blocks']['view']['options']['workinghours'] = array(
         'title'   => html::label($field_id, rcube::Q($this->gettext('workinghours'))),
         'content' => html::div('input-group',
           $select_hours->show($work_start, array('name' => '_work_start', 'id' => $field_id))
           . html::span('input-group-append input-group-prepend', html::span('input-group-text',' &mdash; '))
           . $select_hours->show($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, 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($no_override['calendar_default_alarm_type']) || !isset($no_override['calendar_default_alarm_offset'])) {
       if (!$p['current']) {
         $p['blocks']['view']['content'] = true;
         return $p;
       }
 
       $alarm_type = $alarm_offset = '';
 
       if (!isset($no_override['calendar_default_alarm_type'])) {
         $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) {
           $select_type->add($this->rc->gettext(strtolower("alarm{$type}option"), 'libcalendaring'), $type);
         }
 
         $alarm_type = $select_type->show($this->rc->config->get('calendar_default_alarm_type', ''));
       }
 
       if (!isset($no_override['calendar_default_alarm_offset'])) {
         $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) {
           $select_offset->add($this->rc->gettext('trigger' . $trigger, 'libcalendaring'), $trigger);
         }
 
         $preset = libcalendaring::parse_alarm_value($this->rc->config->get('calendar_default_alarm_offset', '-15M'));
         $alarm_offset = $input_value->show($preset[0]) . ' ' . $select_offset->show($preset[1]);
       }
 
       $p['blocks']['view']['options']['alarmtype'] = array(
         'title' => html::label($field_id, rcube::Q($this->gettext('defaultalarmtype'))),
         'content' => html::div('input-group', $alarm_type . ' ' . $alarm_offset),
       );
     }
 
     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';
       $filter     = calendar_driver::FILTER_PERSONAL | calendar_driver::FILTER_ACTIVE | calendar_driver::FILTER_INSERTABLE;
       $select_cal = new html_select(array('name' => '_default_calendar', 'id' => $field_id, 'is_escaped' => true));
       foreach ((array)$this->driver->list_calendars($filter) 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, rcube::Q($this->gettext('defaultcalendar'))),
         'content' => $select_cal->show($this->rc->config->get('calendar_default_calendar', $default_calendar)),
       );
     }
 
     if (!isset($no_override['calendar_show_weekno'])) {
       if (!$p['current']) {
         $p['blocks']['view']['content'] = true;
         return $p;
       }
 
       $field_id   = 'rcmfd_show_weekno';
       $select = new html_select(array('name' => '_show_weekno', 'id' => $field_id));
       $select->add($this->gettext('weeknonone'), -1);
       $select->add($this->gettext('weeknodatepicker'), 0);
       $select->add($this->gettext('weeknoall'), 1);
 
       $p['blocks']['view']['options']['show_weekno'] = array(
         'title' => html::label($field_id, rcube::Q($this->gettext('showweekno'))),
         'content' => $select->show(intval($this->rc->config->get('calendar_show_weekno'))),
       );
     }
 
     $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' => html::div('input-group input-group-combo', $select->show($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);
           $category_remove = html::span('input-group-append', html::a(array(
               'class'   => 'button icon delete input-group-text',
               'onclick' => '$(this).parent().parent().remove()',
               'title'   => $this->gettext('remove_category'),
               'href'    => '#rcmfd_new_category',
             ), html::span('inner', $this->gettext('delete'))
           ));
           $category_name  = new html_inputfield(array('name' => "_categories[$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 .= $hidden . html::div('input-group', $category_name->show($name) . $category_color->show($color) . $category_remove);
         }
 
         $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 = html::span('input-group-append', html::a(array(
             'type'    => 'button',
             'class'   => 'button create input-group-text',
             'title'   => $this->gettext('add_category'),
             'onclick' => 'rcube_calendar_add_category()',
             'href'    => '#rcmfd_new_category',
           ), html::span('inner', $this->gettext('add_category'))
         ));
         $p['blocks']['categories']['options']['categories'] = array(
           'content' => html::div('input-group', $new_category->show('') . $add_category),
         );
 
         $this->rc->output->add_label('delete', 'calendar.remove_category');
         $this->rc->output->add_script('function rcube_calendar_add_category() {
           var name = $("#rcmfd_new_category").val();
           if (name.length) {
             var button_label = rcmail.gettext("calendar.remove_category");
             var input = $("<input>").attr({type: "text", name: "_categories[]", size: 30, "class": "form-control"}).val(name);
             var color = $("<input>").attr({type: "text", name: "_colors[]", size: 6, "class": "colors form-control"}).val("000000");
             var button = $("<a>").attr({"class": "button icon delete input-group-text", title: button_label, href: "#rcmfd_new_category"})
               .click(function() { $(this).parent().parent().remove(); })
               .append($("<span>").addClass("inner").text(rcmail.gettext("delete")));
 
             $("<div>").addClass("input-group").append(input).append(color).append($("<span class=\'input-group-append\'>").append(button))
               .appendTo("#calendarcategories");
             color.minicolors(rcmail.env.minicolors_config || {});
             $("#rcmfd_new_category").val("");
           }
         }', 'foot');
 
         $this->rc->output->add_script('$("#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::tag('li', null, html::label(null, $checkbox->show($active, array('value' => $source['id'])) . rcube::Q($source['realname'] ?: $source['name'])));
       }
 
       $p['blocks']['birthdays']['options']['birthday_adressbooks'] = array(
         'title'   => rcube::Q($this->gettext('birthdayscalendarsources')),
         'content' => html::tag('ul', 'proplist', implode("\n", $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) {
         $select_type->add($this->rc->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)
         $select_offset->add($this->rc->gettext('trigger' . $trigger, 'libcalendaring'), $trigger);
 
       $preset      = libcalendaring::parse_alarm_value($this->rc->config->get('calendar_birthdays_alarm_offset', '-1D'));
       $preset_type = $this->rc->config->get('calendar_birthdays_alarm_type', '');
 
       $p['blocks']['birthdays']['options']['birthdays_alarmoffset'] = array(
         'title'   => html::label($field_id, rcube::Q($this->gettext('showalarms'))),
         'content' => html::div('input-group', $select_type->show($preset_type) . $input_value->show($preset[0]) . ' ' . $select_offset->show($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_show_weekno'  => intval(rcube_utils::get_input_value('_show_weekno', 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 => $name) {
           if (!isset($colors[$key])) {
             continue;
           }
 
           $color = preg_replace('/^#/', '', strval($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');
         else {
           $calendars = $this->driver->list_calendars();
           $calendar  = $calendars[$cal['id']];
 
           // find parent folder and check if it's a "user calendar"
           // if it's also activated we need to refresh it (#5340)
           while ($calendar['parent']) {
             if (isset($calendars[$calendar['parent']]))
               $calendar = $calendars[$calendar['parent']];
             else
               break;
           }
 
           if ($calendar['id'] != $cal['id'] && $calendar['active'] && $calendar['group'] == "other user")
             $this->rc->output->command('plugin.refresh_source', $calendar['id']);
         }
         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', 'notice');
 
         $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'] = $this->generate_uid();
         if (!$this->write_preprocess($event, $action)) {
           $got_msg = true;
         }
         else if ($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":
         if (!$this->write_preprocess($event, $action)) {
           $got_msg = true;
         }
         else if ($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":
         if (!$this->write_preprocess($event, $action)) {
           $got_msg = true;
         }
         else if ($success = $this->driver->resize_event($event)) {
           $this->event_save_success($event, $old, $action, $success);
         }
         $reload = $event['_savemode'] ? 2 : 1;
         break;
       
       case "move":
         if (!$this->write_preprocess($event, $action)) {
           $got_msg = true;
         }
         else if ($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'];
         $ev['comment']   = $reply_comment;
 
         // 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['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', $success);
 
     // update event object on the client or trigger a complete refresh if too complicated
     if ($reload && empty($_REQUEST['_framed'])) {
       $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()
   {
     $start  = rcube_utils::get_input_value('start', rcube_utils::INPUT_GET);
     $end    = rcube_utils::get_input_value('end', rcube_utils::INPUT_GET);
     $query  = rcube_utils::get_input_value('q', rcube_utils::INPUT_GET);
     $source = rcube_utils::get_input_value('source', rcube_utils::INPUT_GET);
 
     if (!is_numeric($start) || strpos($start, 'T')) {
       $start = new DateTime($start, $this->timezone);
       $start = $start->getTimestamp();
     }
     if (!is_numeric($end) || strpos($end, 'T')) {
       $end = new DateTime($end, $this->timezone);
       $end = $end->getTimestamp();
     }
 
     $events = $this->driver->load_events($start, $end, $query, $source);
     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
    */
   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'])) {
       $this->rc->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 = $this->rc->gettext(array('name' => 'filesizeerror', 'vars' => array(
             'size' => $this->rc->show_bytes(parse_bytes(ini_get('upload_max_filesize'))))));
       }
       else {
         $msg = $this->rc->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->setup();
       $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']);
     $settings['timeslots'] = (int)$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']);
     $settings['show_weekno'] = (int)$this->rc->config->get('calendar_show_weekno', $this->defaults['calendar_show_weekno']);
 
     // 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'])));
     }
 
     // freebusy token authentication URL
     if (($url = $this->rc->config->get('calendar_freebusy_session_auth_url'))
       && ($uniqueid = $this->rc->config->get('kolab_uniqueid'))
     ) {
       if ($url === true) $url = '/freebusy';
       $url = rtrim(rcube_utils::resolve_url($url), '/ ');
       $url .= '/' . urlencode($this->rc->get_user_name());
       $url .= '/' . urlencode($uniqueid);
 
       $settings['freebusy_url'] = $url;
     }
 
     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, $addcss);
     }
     return rcube_output::json_serialize($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']);
 
       unset($event['attachments'][$k]['data'], $event['attachments'][$k]['content']);
 
       if (!$attachment['id']) {
         $event['attachments'][$k]['id'] = $k;
       }
     }
 
     // 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, allday => allDay because of the fullcalendar client script
     $event['vurl'] = $event['url'];
     $event['allDay'] = !empty($event['allday']);
     unset($event['url']);
     unset($event['allday']);
 
     $event['className'] = $event['className'] ? explode(' ', $event['className']) : array();
     if ($addcss) {
         $event['className'][] = 'fc-event-cal-' . asciiwords($event['calendar'], true);
     }
 
     if ($event['allDay']) {
         $event['end'] = $event['end']->add(new DateInterval('P1D'));
     }
 
     if ($_GET['mode'] == 'print') {
         $event['editable'] = false;
     }
 
     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']),
     ) + $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()
   {
     $handler = new kolab_attachments_handler();
     $handler->attachment_upload(self::SESSION_KEY, 'cal-');
   }
 
   /**
    * Handler for attachments download/displaying
    */
   public function attachment_get()
   {
     $handler = new kolab_attachments_handler();
 
     // show loading page
     if (!empty($_GET['_preload'])) {
         return $handler->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);
 
     if ($calendar == '--invitation--itip') {
         $uid  = rcube_utils::get_input_value('_uid', rcube_utils::INPUT_GPC);
         $part = rcube_utils::get_input_value('_part', rcube_utils::INPUT_GPC);
         $mbox = rcube_utils::get_input_value('_mbox', rcube_utils::INPUT_GPC);
 
         $event      = $this->lib->mail_get_itip_object($mbox, $uid, $part, 'event');
         $attachment = $event['attachments'][$id];
         $attachment['body'] = &$attachment['data'];
     }
     else {
         $attachment = $this->driver->get_attachment($id, $event);
     }
 
     // show part page
     if (!empty($_GET['_frame'])) {
         $handler->attachment_page($attachment);
     }
     // deliver attachment content
     else if ($attachment) {
         if ($calendar != '--invitation--itip') {
             $attachment['body'] = $this->driver->get_attachment_body($id, $event);
         }
 
         $handler->attachment_get($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)
   {
     // Remove double timezone specification (T2313)
     $event['start'] = preg_replace('/\s*\(.*\)/', '', $event['start']);
     $event['end']   = preg_replace('/\s*\(.*\)/', '', $event['end']);
 
     // 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);
     $event['allday'] = !empty($event['allDay']);
     unset($event['allDay']);
 
     // start/end is all we need for 'move' action (#1480)
     if ($action == 'move') {
       return true;
     }
 
     // convert the submitted recurrence settings
     if (is_array($event['recurrence'])) {
       $event['recurrence'] = $this->lib->from_client_recurrence($event['recurrence'], $event['start']);
 
       // align start date with the first occurrence
       if (!empty($event['recurrence']) && !empty($event['syncstart'])
         && (empty($event['_savemode']) || $event['_savemode'] == 'all')
       ) {
         $next = $this->find_first_occurrence($event);
 
         if (!$next) {
           $this->rc->output->show_message('calendar.recurrenceerror', 'error');
           return false;
         }
         else if ($event['start'] != $next) {
           $diff = $event['start']->diff($event['end'], true);
 
           $event['start'] = $next;
           $event['end']   = clone $next;
           $event['end']->add($diff);
         }
       }
     }
 
     // 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';
       }
 
       if (!empty($event['_identity'])) {
         $identity = $this->rc->user->get_identity($event['_identity']);
       }
 
       // set new organizer identity
       if ($organizer !== false && $identity) {
         $event['attendees'][$organizer]['name'] = $identity['name'];
         $event['attendees'][$organizer]['email'] = $identity['email'];
       }
       // set owner as organizer if yet missing
       else if ($organizer === false && $owner !== false) {
         $event['attendees'][$owner]['role'] = 'ORGANIZER';
         unset($event['attendees'][$owner]['rsvp']);
       }
       // fallback to the selected identity
       else if ($organizer === false && $identity) {
         $event['attendees'][] = array(
           'role'  => 'ORGANIZER',
           'name'  => $identity['name'],
           'email' => $identity['email'],
         );
       }
     }
 
     // mapping url => vurl because of the fullcalendar client script
     if (array_key_exists('vurl', $event)) {
       $event['url'] = $event['vurl'];
       unset($event['vurl']);
     }
 
     return true;
   }
 
   /**
    * 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
     $this->rc->output->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  = '';
 
     // prepare freebusy list before use (for better performance)
     if (is_array($fblist)) {
       foreach ($fblist as $idx => $slot) {
         list($from, $to, ) = $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
           $fblist[$idx][0] -= $this->gmt_offset;
           $fblist[$idx][1] -= $this->gmt_offset;
         }
       }
     }
 
     // build a list from $start till $end with blocks representing the fb-status
     for ($s = 0, $t = $start; $t <= $end; $s++) {
       $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;
 
           if ($from < $t_end && $to > $t) {
             $status = isset($type) ? $type : self::FREEBUSY_BUSY;
             if ($status == self::FREEBUSY_BUSY)  // can't get any worse :-)
               break;
           }
         }
       }
       else {
         $status = self::FREEBUSY_UNKNOWN;
       }
 
       // use most compact format, assume $status is one digit/character
       $slots .= $status;
       $t = $t_end;
     }
     
     $dte = new DateTime('@'.$t_end);
     $dte->setTimezone($this->timezone);
     
     // let this information be cached for 5min
     $this->rc->output->future_expire_header(300);
     
     echo rcube_output::json_serialize(array(
       'email' => $email,
       'start' => $dts->format('c'),
       'end'   => $dte->format('c'),
       'interval' => $interval,
       'slots' => $slots,
     ));
     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', 'list')))
       $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 JS to the page
     $this->ui->addJS();
 
     $this->register_handler('plugin.calendar_css', array($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');
   }
 
   /**
    * 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 ****/
 
   /**
    * Find an event in user calendars
    */
   protected function find_event($event, &$mode)
   {
     $this->load_driver();
 
     // We search for writeable calendars in personal namespace by default
     $mode   = calendar_driver::FILTER_WRITEABLE | calendar_driver::FILTER_PERSONAL;
     $result = $this->driver->get_event($event, $mode);
     // ... now check shared folders if not found
     if (!$result) {
       $result = $this->driver->get_event($event, calendar_driver::FILTER_WRITEABLE | calendar_driver::FILTER_SHARED);
       if ($result) {
         $mode |= calendar_driver::FILTER_SHARED;
       }
     }
 
     return $result;
   }
 
   /**
    * Handler for calendar/itip-status requests
    */
   function event_itip_status()
   {
     $data = rcube_utils::get_input_value('data', rcube_utils::INPUT_POST, true);
 
     $this->load_driver();
 
     // find local copy of the referenced event (in personal namespace)
     $existing  = $this->find_event($data, $mode);
     $is_shared = $mode & calendar_driver::FILTER_SHARED;
     $itip      = $this->load_itip();
     $response  = $itip->get_itip_status($data, $existing);
 
     // get a list of writeable calendars to save new events to
     if ((!$existing || $is_shared)
       && !$data['nosave']
       && ($response['action'] == 'rsvp' || $response['action'] == 'import')
     ) {
       $calendars       = $this->driver->list_calendars($mode);
       $calendar_select = new html_select(array(
           'name'       => 'calendar',
           'id'         => 'itip-saveto',
           'is_escaped' => true,
           'class'      => 'form-control custom-select'
       ));
       $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'], $calendars);
       $response['select'] = html::span('folder-select', $this->gettext('saveincalendar') . '&nbsp;' .
         $calendar_select->show($is_shared ? $existing['calendar'] : $default_calendar['id']));
     }
     else if ($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
             || $event['status'] == 'CANCELLED'
             || (!empty($event['className']) && strpos($event['className'], 'declined') !== false)
         ) {
           continue;
         }
 
         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);
     $listmode = calendar_driver::FILTER_WRITEABLE | calendar_driver::FILTER_PERSONAL;
 
     // search for event if only UID is given
     if ($event = $this->driver->get_event(array('uid' => $uid, '_instance' => $instance), $listmode)) {
       $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)
   {
     $this->setup();
 
     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...
           // FIXME: we should really consider removing this functionality
           //        it's confusing that it creates/updates an event only for logged-in user
           //        what if the logged-in user is not the same as the attendee?
           if ($this->rc->user->ID) {
             $this->load_driver();
 
             $invitation = $itip->get_invitation($token);
             $existing   = $this->driver->get_event($this->event);
 
             // save the event to his/her default calendar if not yet present
             if (!$existing && ($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');
               else
                 $this->rc->output->command('display_message', $this->gettext('errorimportingevent'), 'error');
             }
             else if ($existing
               && ($this->event['sequence'] >= $existing['sequence'] || $this->event['changed'] >= $existing['changed'])
               && ($calendar = $this->driver->get_calendar($existing['calendar']))
             ) {
               $this->event       = $invitation['event'];
               $this->event['id'] = $existing['id'];
 
               unset($this->event['comment']);
 
               // merge attendees status
               // e.g. preserve my participant status for regular updates
               $this->lib->merge_attendees($this->event, $existing, $status);
 
               // update attachments list
               $event['deleted_attachments'] = true;
 
               // show me as free when declined (#1670)
               if ($status == 'declined')
                 $this->event['free_busy'] = 'free';
 
               if ($this->driver->edit_event($this->event))
                 $this->rc->output->command('display_message', $this->gettext(array('name' => 'updatedsuccessfully', 'vars' => array('calendar' => $calendar->get_name()))), 'confirmation');
               else
                 $this->rc->output->command('display_message', $this->gettext('errorimportingevent'), 'error');
             }
           }
         }
         
         $this->register_handler('plugin.event_inviteform', array($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 ?: $event['className'])),
       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 invitebox boxinformation',
           $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);
     $comment  = rcube_utils::get_input_value('_comment', rcube_utils::INPUT_POST);
 
     $error_msg = $this->gettext('errorimportingevent');
     $success   = false;
 
     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->rc->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 = rcube_utils::get_input_value('_rsvp', rcube_utils::INPUT_POST);
         $itip   = $this->load_itip();
 
         $event['comment'] = $comment;
 
         if ($itip->delegate_to($event, $delegate, !empty($rsvpme))) {
           $this->rc->output->show_message('calendar.itipsendsuccess', 'confirmation');
         }
         else {
           $this->rc->output->command('display_message', $this->gettext('itipresponseerror'), 'error');
         }
 
         unset($event['comment']);
 
         // the delegator is set to non-participant, thus save as non-blocking
         $event['free_busy'] = 'free';
       }
 
       $mode = calendar_driver::FILTER_PERSONAL
         | calendar_driver::FILTER_SHARED
         | calendar_driver::FILTER_WRITEABLE;
 
       // find writeable calendar to store event
       $cal_id    = rcube_utils::get_input_value('_folder', rcube_utils::INPUT_POST);
       $dontsave  = $cal_id === '' && $event['_method'] == 'REQUEST';
       $calendars = $this->driver->list_calendars($mode);
       $calendar  = $calendars[$cal_id];
 
       // select default calendar except user explicitly selected 'none'
       if (!$calendar && !$dontsave)
          $calendar = $this->get_default_calendar($event['sensitivity'], $calendars);
 
       $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 = $this->find_event($event, $mode);
 
         // we'll create a new copy if user decided to change the calendar
         if ($existing && $cal_id && $calendar && $calendar['id'] != $existing['calendar']) {
           $existing = null;
         }
 
         if ($existing) {
           $calendar = $calendars[$existing['calendar']];
 
           // 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[] = $attendee['email'];
               if ($this->itip->compare_email($attendee['email'], $event['_sender'], $event['_sender_utf'])) {
                 $existing_attendee = $i;
               }
             }
 
             $event_attendee   = null;
             $update_attendees = array();
 
             foreach ($event['attendees'] as $attendee) {
               if ($this->itip->compare_email($attendee['email'], $event['_sender'], $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'])
                 && $this->itip->compare_email($attendee['delegated-from'], $event['_sender'], $event['_sender_utf'])
               ) {
                 $update_attendees[] = $attendee;
                 if (!in_array_nocase($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;
                 }
               }
             }
 
             // Accept sender as a new participant (different email in From: and the iTip)
             // Use ATTENDEE entry from the iTip with replaced email address
             if (!$event_attendee) {
               // remove the organizer
               $itip_attendees = array_filter($event['attendees'], function($item) { return $item['role'] != 'ORGANIZER'; });
 
               // there must be only one attendee
               if (is_array($itip_attendees) && count($itip_attendees) == 1) {
                 $event_attendee          = $itip_attendees[key($itip_attendees)];
                 $event_attendee['email'] = $event['_sender'];
                 $update_attendees[]      = $event_attendee;
                 $metadata['fallback']    = $event_attendee['status'];
                 $metadata['attendee']    = $event_attendee['email'];
                 $metadata['rsvp']        = $event_attendee['rsvp'] || $event_attendee['role'] != 'NON-PARTICIPANT';
               }
             }
 
             // 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, $update_attendees);
             }
             else if (!$event_attendee) {
               $error_msg = $this->gettext('errorunknownattendee');
             }
             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'];
 
             // merge attendees status
             // e.g. preserve my participant status for regular updates
             $this->lib->merge_attendees($event, $existing, $status);
 
             // set status=CANCELLED on CANCEL messages
             if ($event['_method'] == 'CANCEL')
               $event['status'] = 'CANCELLED';
 
             // update attachments list, allow attachments update only on REQUEST (#5342)
             if ($event['_method'] == 'REQUEST')
               $event['deleted_attachments'] = true;
             else
               unset($event['attachments']);
 
             // 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'] = $comment;
       $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();
     $imap->set_folder($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()
   {
     $this->ui->init();
     $this->ui->addJS();
     $this->ui->init_templates();
     $this->ui->calendar_list(array(), true); // set env['calendars']
 
     $uid   = rcube_utils::get_input_value('_uid', rcube_utils::INPUT_GET);
     $mbox  = rcube_utils::get_input_value('_mbox', rcube_utils::INPUT_GET);
     $event = array();
 
     // establish imap connection
     $imap    = $this->rc->get_storage();
     $message = new rcube_message($uid, $mbox);
 
     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->set_env('event_prop', $event);
     }
     else {
       $this->rc->output->command('display_message', $this->gettext('messageopenerror'), 'error');
     }
 
     $this->rc->output->send('calendar.dialog');
   }
 
   /**
    * 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'     => $filename . '.ics',
           'mimetype' => 'text/calendar',
           'size'     => filesize($tmp_path),
         );
         $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->setup();
      $this->load_driver();
      return $this->driver->user_delete($args);
   }
 
   /**
    * Find first occurrence of a recurring event excluding start date
    *
    * @param array $event Event data (with 'start' and 'recurrence')
    *
    * @return DateTime Date of the first occurrence
    */
   public function find_first_occurrence($event)
   {
     // Make sure libkolab plugin is loaded in case of Kolab driver
     $this->load_driver();
 
     // Use libkolab to compute recurring events (and libkolab plugin)
     // Horde-based fallback has many bugs
     if (class_exists('kolabformat') && class_exists('kolabcalendaring') && class_exists('kolab_date_recurrence')) {
       $object = kolab_format::factory('event', 3.0);
       $object->set($event);
 
       $recurrence = new kolab_date_recurrence($object);
     }
     else {
       // fallback to libcalendaring (Horde-based) recurrence implementation
       require_once(__DIR__ . '/lib/calendar_recurrence.php');
       $recurrence = new calendar_recurrence($this, $event);
     }
 
     return $recurrence->first_occurrence();
   }
 
   /**
    * 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/calendar_ui.js b/plugins/calendar/calendar_ui.js
index 91575245..1253e0d6 100644
--- a/plugins/calendar/calendar_ui.js
+++ b/plugins/calendar/calendar_ui.js
@@ -1,4359 +1,4263 @@
 /**
  * Client UI Javascript for the Calendar plugin
  *
  * @author Lazlo Westerhof <hello@lazlo.me>
  * @author Thomas Bruederli <bruederli@kolabsys.com>
  *
  * @licstart  The following is the entire license notice for the
  * JavaScript code in this file.
  *
  * 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/>.
  *
  * @licend  The above is the entire license notice
  * for the JavaScript code in this file.
  */
 
 // Roundcube calendar UI client class
 function rcube_calendar_ui(settings)
 {
     // extend base class
     rcube_calendar.call(this, settings);
 
     /***  member vars  ***/
     this.is_loading = false;
     this.selected_event = null;
     this.selected_calendar = null;
     this.search_request = null;
     this.saving_lock = null;
     this.calendars = {};
     this.quickview_sources = [];
 
 
     /***  private vars  ***/
     var DAY_MS = 86400000;
     var HOUR_MS = 3600000;
     var me = this;
     var day_clicked = day_clicked_ts = 0;
     var ignore_click = false;
     var event_defaults = { free_busy:'busy', alarms:'' };
     var event_attendees = [];
     var calendars_list;
     var calenders_search_list;
     var calenders_search_container;
     var search_calendars = {};
     var attendees_list;
     var resources_list;
     var resources_treelist;
     var resources_data = {};
     var resources_index = [];
     var resource_owners = {};
     var resources_events_source = { url:null, editable:false };
     var freebusy_ui = { workinhoursonly:false, needsupdate:false };
     var freebusy_data = {};
     var current_view = null;
     var count_sources = [];
     var event_sources = [];
     var exec_deferred = 1;
     var sensitivitylabels = { 'public':rcmail.gettext('public','calendar'), 'private':rcmail.gettext('private','calendar'), 'confidential':rcmail.gettext('confidential','calendar') };
     var ui_loading = rcmail.set_busy(true, 'loading');
 
     // global fullcalendar settings
     var fullcalendar_defaults = {
       theme: false,
       aspectRatio: 1,
       timezone: false,  // will treat the given date strings as in local (browser's) timezone
       monthNames: settings.months,
       monthNamesShort: settings.months_short,
       dayNames: settings.days,
       dayNamesShort: settings.days_short,
       weekNumbers: settings.show_weekno > 0,
       weekNumberTitle: rcmail.gettext('weekshort', 'calendar') + ' ',
       firstDay: settings.first_day,
       firstHour: settings.first_hour,
       slotDuration: {minutes: 60/settings.timeslots},
       businessHours: {
         start: settings.work_start + ':00',
         end: settings.work_end + ':00'
       },
       scrollTime: settings.work_start + ':00',
       views: {
         list: {
           titleFormat: settings.dates_long,
           listDayFormat: settings.date_long,
           visibleRange: function(currentDate) {
             return {
               start: currentDate.clone(),
               end: currentDate.clone().add(settings.agenda_range, 'days')
             }
           }
         },
         month: {
           columnFormat: 'ddd', // Mon
           titleFormat: 'MMMM YYYY',
           eventLimit: 4
         },
         week: {
           columnFormat: 'ddd ' + settings.date_short, // Mon 9/7
           titleFormat: settings.dates_long
         },
         day: {
           columnFormat: 'dddd ' + settings.date_short,  // Monday 9/7
           titleFormat: 'dddd ' + settings.date_long
         }
       },
       timeFormat: settings.time_format,
       slotLabelFormat: settings.time_format,
       defaultView: rcmail.env.view || settings.default_view,
       allDayText: rcmail.gettext('all-day', 'calendar'),
       buttonText: {
         today: settings['today'],
         day: rcmail.gettext('day', 'calendar'),
         week: rcmail.gettext('week', 'calendar'),
         month: rcmail.gettext('month', 'calendar'),
         list: rcmail.gettext('agenda', 'calendar')
       },
       buttonIcons: {
        prev: 'left-single-arrow',
        next: 'right-single-arrow'
       },
       nowIndicator: settings.time_indicator,
       eventLimitText: function(num) {
         return rcmail.gettext('andnmore', 'calendar').replace('$nr', num);
       },
-/*
-      listTexts: {
-        until: rcmail.gettext('until', 'calendar'),
-        past: rcmail.gettext('pastevents', 'calendar'),
-        today: rcmail.gettext('today', 'calendar'),
-        tomorrow: rcmail.gettext('tomorrow', 'calendar'),
-        thisWeek: rcmail.gettext('thisweek', 'calendar'),
-        nextWeek: rcmail.gettext('nextweek', 'calendar'),
-        thisMonth: rcmail.gettext('thismonth', 'calendar'),
-        nextMonth: rcmail.gettext('nextmonth', 'calendar'),
-        future: rcmail.gettext('futureevents', 'calendar'),
-        week: rcmail.gettext('weekofyear', 'calendar')
-      },
-*/
       // event rendering
       eventRender: function(event, element, view) {
         if (view.name != 'list') {
           var prefix = event.sensitivity && event.sensitivity != 'public' ? String(sensitivitylabels[event.sensitivity]).toUpperCase()+': ' : '';
           element.attr('title', prefix + event.title);
         }
         if (view.name != 'month') {
           if (view.name == 'list') {
             var loc = $('<td>').attr('class', 'fc-event-location');
             if (event.location)
               loc.text(event.location);
             element.find('.fc-list-item-title').after(loc);
           }
           else if (event.location) {
             element.find('div.fc-title').after($('<div class="fc-event-location">').html('@&nbsp;' + Q(event.location)));
           }
           var time_element = element.find('div.fc-time');
           if (event.sensitivity && event.sensitivity != 'public')
             time_element.append('<i class="fc-icon-sensitive"></i>');
           if (event.recurrence)
             time_element.append('<i class="fc-icon-recurring"></i>');
           if (event.alarms || (event.valarms && event.valarms.length))
             time_element.append('<i class="fc-icon-alarms"></i>');
         }
         if (event.status) {
           element.addClass('cal-event-status-' + String(event.status).toLowerCase());
         }
 
         element.attr('aria-label', event.title + ', ' + me.event_date_text(event, true));
       },
       // callback when a specific event is clicked
       eventClick: function(event, ev, view) {
         if (!event.temp && (!event.className || event.className.indexOf('fc-type-freebusy') < 0))
           event_show_dialog(event, ev);
       }
     };
 
     /***  imports  ***/
     var Q = this.quote_html;
     var text2html = this.text2html;
     var event_date_text = this.event_date_text;
     var date2unixtime = this.date2unixtime;
     var fromunixtime = this.fromunixtime;
     var parseISO8601 = this.parseISO8601;
     var date2servertime = this.date2ISO8601;
     var render_message_links = this.render_message_links;
 
 
     /***  private methods  ***/
 
     // same as str.split(delimiter) but it ignores delimiters within quoted strings
     var explode_quoted_string = function(str, delimiter)
     {
       var result = [],
         strlen = str.length,
         q, p, i, chr, last;
 
       for (q = p = i = 0; i < strlen; i++) {
         chr = str.charAt(i);
         if (chr == '"' && last != '\\') {
           q = !q;
         }
         else if (!q && chr == delimiter) {
           result.push(str.substring(p, i));
           p = i + 1;
         }
         last = chr;
       }
 
       result.push(str.substr(p));
       return result;
     };
 
     // Change the first charcter to uppercase
     var ucfirst = function(str)
     {
         return str.charAt(0).toUpperCase() + str.substr(1);
     };
 
     // clone the given date object and optionally adjust time
     var clone_date = function(date, adjust)
     {
       var d = 'toDate' in date ? date.toDate() : new Date(date.getTime());
 
       // set time to 00:00
       if (adjust == 1) {
         d.setHours(0);
         d.setMinutes(0);
       }
       // set time to 23:59
       else if (adjust == 2) {
         d.setHours(23);
         d.setMinutes(59);
       }
 
       return d;
     };
 
     // fix date if jumped over a DST change
     var fix_date = function(date)
     {
       if (date.getHours() == 23)
         date.setTime(date.getTime() + HOUR_MS);
       else if (date.getHours() > 0)
         date.setHours(0);
     };
 
     var date2timestring = function(date, dateonly)
     {
       return date2servertime(date).replace(/[^0-9]/g, '').substr(0, (dateonly ? 8 : 14));
     }
 
     var format_date = function(date, format)
     {
       return $.fullCalendar.formatDate('toDate' in date ? date : moment(date), format);
     };
 
     var format_datetime = function(date, mode, voice)
     {
       return me.format_datetime(date, mode, voice);
     }
 
     var render_link = function(url)
     {
       var islink = false, href = url;
       if (url.match(/^[fhtpsmailo]+?:\/\//i)) {
         islink = true;
       }
       else if (url.match(/^[a-z0-9.-:]+(\/|$)/i)) {
         islink = true;
         href = 'http://' + url;
       }
       return islink ? '<a href="' + Q(href) + '" target="_blank">' + Q(url) + '</a>' : Q(url);
     }
 
     // determine whether the given date is on a weekend
     var is_weekend = function(date)
     {
       return date.getDay() == 0 || date.getDay() == 6;
     };
 
     var is_workinghour = function(date)
     {
       if (settings['work_start'] > settings['work_end'])
         return date.getHours() >= settings['work_start'] || date.getHours() < settings['work_end'];
       else
         return date.getHours() >= settings['work_start'] && date.getHours() < settings['work_end'];
     };
 
     var load_attachment = function(data)
     {
       var event = data.record,
         query = {_id: data.attachment.id, _event: event.recurrence_id || event.id, _cal: event.calendar};
 
       if (event.rev)
         query._rev = event.rev;
 
       if (event.calendar == "--invitation--itip")
         $.extend(query, {_uid: event._uid, _part: event._part, _mbox: event._mbox});
 
       libkolab.load_attachment(query, data.attachment);
     };
 
     // build event attachments list
     var event_show_attachments = function(list, container, event, edit)
     {
       libkolab.list_attachments(list, container, edit, event,
         function(id) { remove_attachment(id); },
         function(data) { load_attachment(data); }
       );
     };
 
     var remove_attachment = function(id)
     {
       rcmail.env.deleted_attachments.push(id);
     };
 
     // event details dialog (show only)
     var event_show_dialog = function(event, ev, temp)
     {
       var $dialog = $("#eventshow");
       var calendar = event.calendar && me.calendars[event.calendar] ? me.calendars[event.calendar] : { editable:false, rights:'lrs' };
 
       if (!temp)
         me.selected_event = event;
 
       if ($dialog.is(':ui-dialog'))
         $dialog.dialog('close');
 
       // remove status-* and sensitivity-* classes
       $dialog.removeClass(function(i, oldclass) {
           var oldies = String(oldclass).split(' ');
           return $.grep(oldies, function(cls) { return cls.indexOf('status-') === 0 || cls.indexOf('sensitivity-') === 0 }).join(' ');
       });
 
       // convert start/end dates if not done yet by fullcalendar
       if (typeof event.start == 'string')
         event.start = parseISO8601(event.start);
       if (typeof event.end == 'string')
         event.end = parseISO8601(event.end);
 
       // allow other plugins to do actions when event form is opened
       rcmail.triggerEvent('calendar-event-init', {o: event});
 
       $dialog.find('div.event-section, div.event-line, .form-group').hide();
       $('#event-title').html(Q(event.title)).show();
       
       if (event.location)
         $('#event-location').html('@ ' + text2html(event.location)).show();
       if (event.description)
         $('#event-description').show().find('.event-text').html(text2html(event.description, 300, 6));
       if (event.vurl)
         $('#event-url').show().find('.event-text').html(render_link(event.vurl));
       
       // render from-to in a nice human-readable way
       // -> now shown in dialog title
       // $('#event-date').html(Q(me.event_date_text(event))).show();
       
       if (event.recurrence && event.recurrence_text)
         $('#event-repeat').show().find('.event-text').html(Q(event.recurrence_text));
       
       if (event.valarms && event.alarms_text)
         $('#event-alarm').show().find('.event-text').html(Q(event.alarms_text).replace(',', ',<br>'));
       
       if (calendar.name)
         $('#event-calendar').show().find('.event-text').html(Q(calendar.name)).addClass('cal-'+calendar.id).css('color', calendar.textColor || calendar.color || '');
       if (event.categories)
         $('#event-category').show().find('.event-text').html(Q(event.categories)).addClass('cat-'+String(event.categories).toLowerCase().replace(rcmail.identifier_expr, ''));
       if (event.free_busy)
         $('#event-free-busy').show().find('.event-text').text(rcmail.gettext(event.free_busy, 'calendar'));
       if (event.priority > 0) {
         var priolabels = [ '', rcmail.gettext('highest'), rcmail.gettext('high'), '', '', rcmail.gettext('normal'), '', '', rcmail.gettext('low'), rcmail.gettext('lowest') ];
         $('#event-priority').show().find('.event-text').html(Q(event.priority+' '+priolabels[event.priority]));
       }
 
       if (event.status) {
         var status_lc = String(event.status).toLowerCase();
         $('#event-status').show().find('.event-text').text(rcmail.gettext('status-'+status_lc,'calendar'));
         $('#event-status-badge > span').text(rcmail.gettext('status-'+status_lc,'calendar'));
         $dialog.addClass('status-'+status_lc);
       }
       if (event.sensitivity && event.sensitivity != 'public') {
         $('#event-sensitivity').show().find('.event-text').text(sensitivitylabels[event.sensitivity]);
         $('#event-status-badge > span').text(sensitivitylabels[event.sensitivity]);
         $dialog.addClass('sensitivity-'+event.sensitivity);
       }
       if (event.created || event.changed) {
         var created = parseISO8601(event.created),
           changed = parseISO8601(event.changed);
         $('.event-created', $dialog).text(created ? format_datetime(created) : rcmail.gettext('unknown','calendar'));
         $('.event-changed', $dialog).text(changed ? format_datetime(changed) : rcmail.gettext('unknown','calendar'));
         $('#event-created,#event-changed,#event-created-changed').show()
       }
 
       // create attachments list
       if ($.isArray(event.attachments)) {
         event_show_attachments(event.attachments, $('#event-attachments').find('.event-text'), event);
         if (event.attachments.length > 0) {
           $('#event-attachments').show();
         }
       }
       else if (calendar.attachments) {
         // fetch attachments, some drivers doesn't set 'attachments' prop of the event?
       }
 
       // build attachments list
       $('#event-links').hide();
       if ($.isArray(event.links) && event.links.length) {
           render_message_links(event.links || [], $('#event-links').find('.event-text'), false, 'calendar');
           $('#event-links').show();
       }
 
       // list event attendees
       if (calendar.attendees && event.attendees) {
         // sort resources to the end
         event.attendees.sort(function(a,b) {
           var j = a.cutype == 'RESOURCE' ? 1 : 0,
               k = b.cutype == 'RESOURCE' ? 1 : 0;
           return (j - k);
         });
 
         var data, mystatus = null, rsvp, line, morelink, html = '', overflow = '',
           organizer = me.is_organizer(event);
 
         for (var j=0; j < event.attendees.length; j++) {
           data = event.attendees[j];
           if (data.email) {
             if (data.role != 'ORGANIZER' && settings.identity.emails.indexOf(';'+data.email) >= 0) {
               mystatus = (data.status || 'UNKNOWN').toLowerCase();
               if (data.status == 'NEEDS-ACTION' || data.status == 'TENTATIVE' || data.rsvp)
                 rsvp = mystatus;
             }
           }
 
           line = rcube_libcalendaring.attendee_html(data);
 
           if (morelink)
             overflow += ' ' + line;
           else
             html += ' ' + line;
 
           // stop listing attendees
           if (j == 7 && event.attendees.length >= 7) {
             morelink = $('<a href="#more" class="morelink"></a>').html(rcmail.gettext('andnmore', 'calendar').replace('$nr', event.attendees.length - j - 1));
           }
         }
 
         if (html && (event.attendees.length > 1 || !organizer)) {
           $('#event-attendees').show()
             .find('.event-text')
             .html(html)
             .find('a.mailtolink').click(event_attendee_click);
 
           // display all attendees in a popup when clicking the "more" link
           if (morelink) {
             $('#event-attendees .event-text').append(morelink);
             morelink.click(function(e){
               rcmail.simple_dialog(
                 '<div id="all-event-attendees" class="event-attendees">' + html + overflow + '</div>',
                 rcmail.gettext('tabattendees','calendar'),
                 null,
                 {width: 450, cancel_button: 'close'});
               $('#all-event-attendees a.mailtolink').click(event_attendee_click);
               return false;
             });
           }
         }
 
         if (mystatus && !rsvp) {
           $('#event-partstat').show().find('.changersvp, .event-text')
             .removeClass('accepted tentative declined delegated needs-action unknown')
             .addClass(mystatus);
           $('#event-partstat').find('.event-text')
             .text(rcmail.gettext('status' + mystatus, 'libcalendaring'));
         }
 
         var show_rsvp = rsvp && !organizer && event.status != 'CANCELLED' && me.has_permission(calendar, 'v');
         $('#event-rsvp')[(show_rsvp ? 'show' : 'hide')]();
         $('#event-rsvp .rsvp-buttons input').prop('disabled', false).filter('input[rel="'+(mystatus || '')+'"]').prop('disabled', true);
 
         if (show_rsvp && event.comment)
           $('#event-rsvp-comment').show().find('.event-text').html(Q(event.comment));
 
         $('#event-rsvp a.reply-comment-toggle').show();
         $('#event-rsvp .itip-reply-comment textarea').hide().val('');
 
         if (event.recurrence && event.id) {
           var sel = event._savemode || (event.thisandfuture ? 'future' : (event.isexception ? 'current' : 'all'));
           $('#event-rsvp .rsvp-buttons').addClass('recurring');
         }
         else {
           $('#event-rsvp .rsvp-buttons').removeClass('recurring');
         }
       }
 
       var buttons = [];
       if (!temp && calendar.editable && event.editable !== false) {
         buttons.push({
           text: rcmail.gettext('edit', 'calendar'),
           'class': 'edit mainaction',
           click: function() {
             event_edit_dialog('edit', event);
           }
         });
       }
       if (!temp && me.has_permission(calendar, 'td') && event.editable !== false) {
         buttons.push({
           text: rcmail.gettext('delete', 'calendar'),
           'class': 'delete',
           click: function() {
             me.delete_event(event);
             $dialog.dialog('close');
           }
         });
       }
 
       buttons.push({
         text: rcmail.gettext('close', 'calendar'),
         'class': 'cancel',
         click: function() {
           $dialog.dialog('close');
         }
       });
 
       // open jquery UI dialog
       $dialog.dialog({
         modal: true,
         resizable: true,
         closeOnEscape: true,
         title: me.event_date_text(event),
         open: function() {
           $dialog.attr('aria-hidden', 'false');
           setTimeout(function(){
             $dialog.parent().find('.ui-button:not(.ui-dialog-titlebar-close)').first().focus();
           }, 5);
         },
         beforeClose: function(e) {
           rcmail.command('menu-close', 'eventoptionsmenu', null, e);
         },
         close: function(e) {
           $dialog.dialog('destroy').attr('aria-hidden', 'true').hide();
           $('.libcal-rsvp-replymode').hide();
         },
         dragStart: function(e) {
           rcmail.command('menu-close', 'eventoptionsmenu', null, e);
           $('.libcal-rsvp-replymode').hide();
         },
         resizeStart: function(e) {
           rcmail.command('menu-close', 'eventoptionsmenu', null, e);
           $('.libcal-rsvp-replymode').hide();
         },
         buttons: buttons,
         minWidth: 320,
         width: 420
       }).show();
 
       // remember opener element (to be focused on close)
       $dialog.data('opener', ev && rcube_event.is_keyboard(ev) ? ev.target : null);
 
       // set voice title on dialog widget
       $dialog.dialog('widget').removeAttr('aria-labelledby')
         .attr('aria-label', me.event_date_text(event, true) + ', ', event.title);
 
       // set dialog size according to content
       me.dialog_resize($dialog.get(0), $dialog.height(), 420);
 
       // add link for "more options" drop-down
       if (!temp && !event.temporary && event.calendar != '_resource') {
         $('<a>')
           .attr({href: '#', 'class': 'dropdown-link btn btn-link options', 'data-popup-pos': 'top'})
           .text(rcmail.gettext('eventoptions','calendar'))
           .click(function(e) {
             return rcmail.command('menu-open','eventoptionsmenu', this, e)
           })
           .appendTo($dialog.parent().find('.ui-dialog-buttonset'));
       }
 
       rcmail.enable_command('event-history', calendar.history)
 
       rcmail.triggerEvent('calendar-event-dialog', {dialog: $dialog});
     };
 
     // event handler for clicks on an attendee link
     var event_attendee_click = function(e)
     {
       var cutype = $(this).attr('data-cutype'),
         mailto = this.href.substr(7);
       if (rcmail.env.calendar_resources && cutype == 'RESOURCE') {
         event_resources_dialog(mailto);
       }
       else {
         rcmail.command('compose', mailto, e ? e.target : null, e);
       }
       return false;
     };
 
     // bring up the event dialog (jquery-ui popup)
     var event_edit_dialog = function(action, event)
     {
       // copy opener element from show dialog
       var op_elem = $("#eventshow:ui-dialog").data('opener');
 
       // close show dialog first
       $("#eventshow:ui-dialog").data('opener', null).dialog('close');
 
       var $dialog = $('<div>');
       var calendar = event.calendar && me.calendars[event.calendar] ? me.calendars[event.calendar] : { editable:true, rights: action=='new' ? 'lrwitd' : 'lrs' };
       me.selected_event = $.extend($.extend({}, event_defaults), event);  // clone event object (with defaults)
       event = me.selected_event; // change reference to clone
       freebusy_ui.needsupdate = false;
 
       if (rcmail.env.action == 'dialog-ui')
         calendar.attendees = false; // TODO: allow Attendees tab in Save-as-event dialog
 
       // reset dialog first
       $('#eventedit form').trigger('reset');
       $('#event-panel-recurrence input, #event-panel-recurrence select, #event-panel-attachments input').prop('disabled', false);
       $('#event-panel-recurrence, #event-panel-attachments').removeClass('disabled');
 
       // allow other plugins to do actions when event form is opened
       rcmail.triggerEvent('calendar-event-init', {o: event});
 
       // event details
       var title = $('#edit-title').val(event.title || '');
       var location = $('#edit-location').val(event.location || '');
       var description = $('#edit-description').text(event.description || '');
       var vurl = $('#edit-url').val(event.vurl || '');
       var categories = $('#edit-categories').val(event.categories);
       var calendars = $('#edit-calendar').val(event.calendar);
       var eventstatus = $('#edit-event-status').val(event.status);
       var freebusy = $('#edit-free-busy').val(event.free_busy);
       var priority = $('#edit-priority').val(event.priority);
       var sensitivity = $('#edit-sensitivity').val(event.sensitivity);
       var syncstart = $('#edit-recurrence-syncstart input');
       var end = 'toDate' in event.end ? event.end : moment(event.end);
       var start = 'toDate' in event.start ? event.start : moment(event.start);
       var duration = Math.round((end.format('x') - start.format('x')) / 1000);
 
       // Correct the fullCalendar end date for all-day events
       if (!end.hasTime()) {
         end.subtract(1, 'days');
       }
 
       var startdate = $('#edit-startdate').val(format_date(start, settings.date_format)).data('duration', duration);
       var starttime = $('#edit-starttime').val(format_date(start, settings.time_format)).show();
       var enddate = $('#edit-enddate').val(format_date(end, settings.date_format));
       var endtime = $('#edit-endtime').val(format_date(end, settings.time_format)).show();
       var allday = $('#edit-allday').get(0);
       var notify = $('#edit-attendees-donotify').get(0);
       var invite = $('#edit-attendees-invite').get(0);
       var comment = $('#edit-attendees-comment');
 
       // make sure any calendar is selected
       if (!calendars.val())
         calendars.val($('option:first', calendars).attr('value'));
 
       invite.checked = settings.itip_notify & 1 > 0;
       notify.checked = me.has_attendees(event) && invite.checked;
 
       if (event.allDay) {
         starttime.val("12:00").hide();
         endtime.val("13:00").hide();
         allday.checked = true;
       }
       else {
         allday.checked = false;
       }
 
       // set calendar selection according to permissions
       calendars.find('option').each(function(i, opt) {
         var cal = me.calendars[opt.value] || {};
         $(opt).prop('disabled', !(cal.editable || (action == 'new' && me.has_permission(cal, 'i'))))
       });
 
       // set alarm(s)
       me.set_alarms_edit('#edit-alarms', action != 'new' && event.valarms && calendar.alarms ? event.valarms : []);
 
       // enable/disable alarm property according to backend support
       $('#edit-alarms')[(calendar.alarms ? 'show' : 'hide')]();
 
       // check categories drop-down: add value if not exists
       if (event.categories && !categories.find("option[value='"+event.categories+"']").length) {
         $('<option>').attr('value', event.categories).text(event.categories).appendTo(categories).prop('selected', true);
       }
 
       if ($.isArray(event.links) && event.links.length) {
           render_message_links(event.links, $('#edit-event-links .event-text'), true, 'calendar');
           $('#edit-event-links').show();
       }
       else {
           $('#edit-event-links').hide();
       }
 
       // show warning if editing a recurring event
       if (event.id && event.recurrence) {
         var sel = event._savemode || (event.thisandfuture ? 'future' : (event.isexception ? 'current' : 'all'));
         $('#edit-recurring-warning').show();
         $('input.edit-recurring-savemode[value="'+sel+'"]').prop('checked', true).change();
       }
       else
         $('#edit-recurring-warning').hide();
 
       // init attendees tab
       var organizer = !event.attendees || me.is_organizer(event),
         allow_invitations = organizer || (calendar.owner && calendar.owner == 'anonymous') || settings.invite_shared;
       event_attendees = [];
       attendees_list = $('#edit-attendees-table > tbody').html('');
       resources_list = $('#edit-resources-table > tbody').html('');
       $('#edit-attendees-notify')[(action != 'new' && allow_invitations && me.has_attendees(event) && (settings.itip_notify & 2) ? 'show' : 'hide')]();
       $('#edit-localchanges-warning')[(action != 'new' && me.has_attendees(event) && !(allow_invitations || (calendar.owner && me.is_organizer(event, calendar.owner))) ? 'show' : 'hide')]();
 
       var load_attendees_tab = function()
       {
         var j, data, organizer_attendee, reply_selected = 0;
         if (event.attendees) {
           for (j=0; j < event.attendees.length; j++) {
             data = event.attendees[j];
             // reset attendee status
             if (event._savemode == 'new' && data.role != 'ORGANIZER') {
               data.status = 'NEEDS-ACTION';
               delete data.noreply;
             }
             add_attendee(data, !allow_invitations);
             if (allow_invitations && data.role != 'ORGANIZER' && !data.noreply)
               reply_selected++;
 
             if (data.role == 'ORGANIZER')
               organizer_attendee = data;
           }
         }
 
         // make sure comment box is visible if at least one attendee has reply enabled
         // or global "send invitations" checkbox is checked
         $('#eventedit .attendees-commentbox')[(reply_selected || invite.checked ? 'show' : 'hide')]();
 
         // select the correct organizer identity
         var identity_id = 0;
         $.each(settings.identities, function(i,v){
           if (organizer && typeof organizer == 'object' && v == organizer.email) {
             identity_id = i;
             return false;
           }
         });
 
         // In case the user is not the (shared) event organizer we'll add the organizer to the selection list
         if (!identity_id && !organizer && organizer_attendee) {
           var organizer_name = organizer_attendee.email;
           if (organizer_attendee.name)
             organizer_name = '"' + organizer_attendee.name + '" <' + organizer_name + '>';
           $('#edit-identities-list').append($('<option value="0">').text(organizer_name));
         }
 
         $('#edit-identities-list').val(identity_id);
         $('#edit-attendees-form')[(allow_invitations?'show':'hide')]();
         $('#edit-attendee-schedule')[(calendar.freebusy?'show':'hide')]();
       };
 
       // attachments
       var load_attachments_tab = function()
       {
         rcmail.enable_command('remove-attachment', 'upload-file', calendar.editable && !event.recurrence_id);
         rcmail.env.deleted_attachments = [];
         // we're sharing some code for uploads handling with app.js
         rcmail.env.attachments = [];
         rcmail.env.compose_id = event.id; // for rcmail.async_upload_form()
 
         if ($.isArray(event.attachments)) {
           event_show_attachments(event.attachments, $('#edit-attachments'), event, true);
         }
         else {
           $('#edit-attachments > ul').empty();
           // fetch attachments, some drivers doesn't set 'attachments' array for event?
         }
       };
 
       // init dialog buttons
       var buttons = [],
         save_func = function() {
           var start = me.parse_datetime(allday.checked ? '12:00' : starttime.val(), startdate.val());
           var end   = me.parse_datetime(allday.checked ? '13:00' : endtime.val(), enddate.val());
 
           // basic input validatetion
           if (start.getTime() > end.getTime()) {
             rcmail.alert_dialog(rcmail.gettext('invalideventdates', 'calendar'));
             return false;
           }
 
           // post data to server
           var data = {
             calendar: event.calendar,
             start: date2servertime(start),
             end: date2servertime(end),
             allDay: allday.checked?1:0,
             title: title.val(),
             description: description.val(),
             location: location.val(),
             categories: categories.val(),
             vurl: vurl.val(),
             free_busy: freebusy.val(),
             priority: priority.val(),
             sensitivity: sensitivity.val(),
             status: eventstatus.val(),
             recurrence: me.serialize_recurrence(endtime.val()),
             valarms: me.serialize_alarms('#edit-alarms'),
             attendees: event_attendees,
             links: me.selected_event.links,
             deleted_attachments: rcmail.env.deleted_attachments,
             attachments: []
           };
 
           // uploaded attachments list
           for (var i in rcmail.env.attachments)
             if (i.match(/^rcmfile(.+)/))
               data.attachments.push(RegExp.$1);
 
           // read attendee roles
           $('select.edit-attendee-role').each(function(i, elem){
             if (data.attendees[i])
               data.attendees[i].role = $(elem).val();
           });
 
           if (organizer)
             data._identity = $('#edit-identities-list option:selected').val();
 
           // per-attendee notification suppression
           var need_invitation = false;
           if (allow_invitations) {
             $.each(data.attendees, function (i, v) {
               if (v.role != 'ORGANIZER') {
                 if ($('input.edit-attendee-reply[value="' + v.email + '"]').prop('checked') || v.cutype == 'RESOURCE') {
                   need_invitation = true;
                   delete data.attendees[i]['noreply'];
                 }
                 else if (settings.itip_notify > 0) {
                   data.attendees[i].noreply = 1;
                 }
               }
             });
           }
 
           // tell server to send notifications
           if ((data.attendees.length || (event.id && event.attendees.length)) && allow_invitations && (notify.checked || invite.checked || need_invitation)) {
             data._notify = settings.itip_notify;
             data._comment = comment.val();
           }
 
           data.calendar = calendars.val();
 
           if (event.id) {
             data.id = event.id;
             if (event.recurrence)
               data._savemode = $('input.edit-recurring-savemode:checked').val();
             if (data.calendar && data.calendar != event.calendar)
               data._fromcalendar = event.calendar;
           }
 
           if (data.recurrence && syncstart.is(':checked'))
             data.syncstart = 1;
 
           update_event(action, data);
 
           if (rcmail.env.action != 'dialog-ui')
             $dialog.dialog("close");
         };
 
       rcmail.env.event_save_func = save_func;
 
       // save action
       buttons.push({
         text: rcmail.gettext('save', 'calendar'),
         'class': 'save mainaction',
         click: save_func
       });
 
       buttons.push({
         text: rcmail.gettext('cancel', 'calendar'),
         'class': 'cancel',
         click: function() {
           $dialog.dialog("close");
         }
       });
 
       // show/hide tabs according to calendar's feature support and activate first tab (Larry)
       $('#edit-tab-attendees')[(calendar.attendees?'show':'hide')]();
       $('#edit-tab-resources')[(rcmail.env.calendar_resources?'show':'hide')]();
       $('#edit-tab-attachments')[(calendar.attachments?'show':'hide')]();
       $('#eventedit:not([data-notabs])').tabs('option', 'active', 0); // Larry
 
       // show/hide tabs according to calendar's feature support and activate first tab (Ellastic)
       $('li > a[href="#event-panel-attendees"]').parent()[(calendar.attendees?'show':'hide')]();
       $('li > a[href="#event-panel-resources"]').parent()[(rcmail.env.calendar_resources?'show':'hide')]();
       $('li > a[href="#event-panel-attachments"]').parent()[(calendar.attachments?'show':'hide')]();
       if ($('#eventedit').data('notabs'))
         $('#eventedit li.nav-item:first-child a').tab('show');
 
       // hack: set task to 'calendar' to make all dialog actions work correctly
       var comm_path_before = rcmail.env.comm_path;
       rcmail.env.comm_path = comm_path_before.replace(/_task=[a-z]+/, '_task=calendar');
 
       var editform = $("#eventedit");
 
       if (rcmail.env.action != 'dialog-ui') {
         // open jquery UI dialog
         $dialog.dialog({
           modal: true,
           resizable: true,
           closeOnEscape: false,
           title: rcmail.gettext((action == 'edit' ? 'edit_event' : 'new_event'), 'calendar'),
           open: function() {
             editform.attr('aria-hidden', 'false');
           },
           close: function() {
             editform.hide().attr('aria-hidden', 'true').appendTo(document.body);
             $dialog.dialog("destroy").remove();
             rcmail.ksearch_blur();
             freebusy_data = {};
             rcmail.env.comm_path = comm_path_before;  // restore comm_path
             if (op_elem)
               $(op_elem).focus();
           },
           buttons: buttons,
           minWidth: 500,
           width: 600
         }).append(editform.show());  // adding form content AFTERWARDS massively speeds up opening on IE6
 
         // set dialog size according to form content
         me.dialog_resize($dialog.get(0), editform.height() + (bw.ie ? 20 : 0), 550);
 
         rcmail.triggerEvent('calendar-event-dialog', {dialog: $dialog});
       }
 
       // init other tabs asynchronously
       window.setTimeout(function(){ me.set_recurrence_edit(event); }, exec_deferred);
       if (calendar.attendees)
         window.setTimeout(load_attendees_tab, exec_deferred);
       if (calendar.attachments)
         window.setTimeout(load_attachments_tab, exec_deferred);
 
       title.select();
     };
 
     // show event changelog in a dialog
     var event_history_dialog = function(event)
     {
       if (!event.id || !window.libkolab_audittrail)
         return false
 
       // render dialog
       var $dialog = libkolab_audittrail.object_history_dialog({
         module: 'calendar',
         container: '#eventhistory',
         title: rcmail.gettext('objectchangelog','calendar') + ' - ' + event.title + ', ' + me.event_date_text(event),
 
         // callback function for list actions
         listfunc: function(action, rev) {
           me.loading_lock = rcmail.set_busy(true, 'loading', me.loading_lock);
           rcmail.http_post('event', { action:action, e:{ id:event.id, calendar:event.calendar, rev: rev } }, me.loading_lock);
         },
 
         // callback function for comparing two object revisions
         comparefunc: function(rev1, rev2) {
           me.loading_lock = rcmail.set_busy(true, 'loading', me.loading_lock);
           rcmail.http_post('event', { action:'diff', e:{ id:event.id, calendar:event.calendar, rev1: rev1, rev2: rev2 } }, me.loading_lock);
         }
       });
 
       $dialog.data('event', event);
 
       // fetch changelog data
       me.loading_lock = rcmail.set_busy(true, 'loading', me.loading_lock);
       rcmail.http_post('event', { action:'changelog', e:{ id:event.id, calendar:event.calendar } }, me.loading_lock);
     };
 
     // callback from server with changelog data
     var render_event_changelog = function(data)
     {
       var $dialog = $('#eventhistory'),
         event = $dialog.data('event');
 
       if (data === false || !data.length || !event) {
         // display 'unavailable' message
         $('<div class="notfound-message dialog-message warning">' + rcmail.gettext('objectchangelognotavailable','calendar') + '</div>')
           .insertBefore($dialog.find('.changelog-table').hide());
         return;
       }
 
       data.module = 'calendar';
       libkolab_audittrail.render_changelog(data, event, me.calendars[event.calendar]);
 
       // set dialog size according to content
       me.dialog_resize($dialog.get(0), $dialog.height(), 600);
     };
 
     // callback from server with event diff data
     var event_show_diff = function(data)
     {
       var event = me.selected_event,
         $dialog = $("#eventdiff");
 
       $dialog.find('div.event-section, div.event-line, h1.event-title-new').hide().data('set', false).find('.index').html('');
       $dialog.find('div.event-section.clone, div.event-line.clone').remove();
 
       // always show event title and date
       $('.event-title', $dialog).text(event.title).removeClass('event-text-old').show();
       $('.event-date', $dialog).text(me.event_date_text(event)).show();
 
       // show each property change
       $.each(data.changes, function(i,change) {
         var prop = change.property, r2, html = false,
           row = $('div.event-' + prop, $dialog).first();
 
           // special case: title
           if (prop == 'title') {
             $('.event-title', $dialog).addClass('event-text-old').text(change['old'] || '--');
             $('.event-title-new', $dialog).text(change['new'] || '--').show();
           }
 
           // no display container for this property
           if (!row.length) {
             return true;
           }
 
           // clone row if already exists
           if (row.data('set')) {
             r2 = row.clone().addClass('clone').insertAfter(row);
             row = r2;
           }
 
           // format dates
           if (['start','end','changed'].indexOf(prop) >= 0) {
             if (change['old']) change.old_ = me.format_datetime(parseISO8601(change['old']));
             if (change['new']) change.new_ = me.format_datetime(parseISO8601(change['new']));
           }
           // render description text
           else if (prop == 'description') {
             // TODO: show real text diff
             if (!change.diff_ && change['old']) change.old_ = text2html(change['old']);
             if (!change.diff_ && change['new']) change.new_ = text2html(change['new']);
             html = true;
           }
           // format attendees struct
           else if (prop == 'attendees') {
             if (change['old']) change.old_ = rcube_libcalendaring.attendee_html(change['old']);
             if (change['new']) change.new_ = rcube_libcalendaring.attendee_html($.extend({}, change['old'] || {}, change['new']));
             html = true;
           }
           // localize priority values
           else if (prop == 'priority') {
             var priolabels = [ '', rcmail.gettext('highest'), rcmail.gettext('high'), '', '', rcmail.gettext('normal'), '', '', rcmail.gettext('low'), rcmail.gettext('lowest') ];
             if (change['old']) change.old_ = change['old'] + ' ' + (priolabels[change['old']] || '');
             if (change['new']) change.new_ = change['new'] + ' ' + (priolabels[change['new']] || '');
           }
           // localize status
           else if (prop == 'status') {
             var status_lc = String(event.status).toLowerCase();
             if (change['old']) change.old_ = rcmail.gettext(String(change['old']).toLowerCase(), 'calendar');
             if (change['new']) change.new_ = rcmail.gettext(String(change['new']).toLowerCase(), 'calendar');
           }
 
           // format attachments struct
           if (prop == 'attachments') {
             if (change['old']) event_show_attachments([change['old']], row.children('.event-text-old'), event, false);
             else            row.children('.event-text-old').text('--');
             if (change['new']) event_show_attachments([$.extend({}, change['old'] || {}, change['new'])], row.children('.event-text-new'), event, false);
             else            row.children('.event-text-new').text('--');
             // remove click handler as we're currentyl not able to display the according attachment contents
             $('.attachmentslist li a', row).unbind('click').removeAttr('href');
           }
           else if (change.diff_) {
             row.children('.event-text-diff').html(change.diff_);
             row.children('.event-text-old, .event-text-new').hide();
           }
           else {
             if (!html) {
               // escape HTML characters
               change.old_ = Q(change.old_ || change['old'] || '--')
               change.new_ = Q(change.new_ || change['new'] || '--')
             }
             row.children('.event-text-old').html(change.old_ || change['old'] || '--');
             row.children('.event-text-new').html(change.new_ || change['new'] || '--');
           }
 
           // display index number
           if (typeof change.index != 'undefined') {
             row.find('.index').html('(' + change.index + ')');
           }
 
           row.show().data('set', true);
 
           // hide event-date line
           if (prop == 'start' || prop == 'end')
             $('.event-date', $dialog).hide();
       });
 
       var buttons = [{
         text: rcmail.gettext('close', 'calendar'),
         'class': 'cancel',
         click: function() { $dialog.dialog('close'); }
       }];
 
       // open jquery UI dialog
       $dialog.dialog({
         modal: false,
         resizable: true,
         closeOnEscape: true,
         title: rcmail.gettext('objectdiff','calendar').replace('$rev1', data.rev1).replace('$rev2', data.rev2) + ' - ' + event.title,
         open: function() {
           $dialog.attr('aria-hidden', 'false');
           setTimeout(function(){
             $dialog.parent().find('.ui-button:not(.ui-dialog-titlebar-close)').first().focus();
           }, 5);
         },
         close: function() {
           $dialog.dialog('destroy').attr('aria-hidden', 'true').hide();
         },
         buttons: buttons,
         minWidth: 320,
         width: 450
       }).show();
 
       // set dialog size according to content
       me.dialog_resize($dialog.get(0), $dialog.height(), 400);
     };
 
     // close the event history dialog
     var close_history_dialog = function()
     {
       $('#eventhistory, #eventdiff').each(function(i, elem) {
         var $dialog = $(elem);
         if ($dialog.is(':ui-dialog'))
           $dialog.dialog('close');
       });
     }
 
     // exports
     this.event_show_diff = event_show_diff;
     this.event_show_dialog = event_show_dialog;
     this.event_history_dialog = event_history_dialog;
     this.render_event_changelog = render_event_changelog;
     this.close_history_dialog = close_history_dialog;
 
     // open a dialog to display detailed free-busy information and to find free slots
     var event_freebusy_dialog = function()
     {
       var $dialog = $('#eventfreebusy'),
         event = me.selected_event;
       
       if ($dialog.is(':ui-dialog'))
         $dialog.dialog('close');
       
       if (!event_attendees.length)
         return false;
       
       // set form elements
       var allday = $('#edit-allday').get(0);
       var end = 'toDate' in event.end ? event.end : moment(event.end);
       var start = 'toDate' in event.start ? event.start : moment(event.start);
       var duration = Math.round((end.format('x') - start.format('x')) / 1000);
 
       freebusy_ui.startdate = $('#schedule-startdate').val(format_date(start, settings.date_format)).data('duration', duration);
       freebusy_ui.starttime = $('#schedule-starttime').val(format_date(start, settings.time_format)).show();
       freebusy_ui.enddate = $('#schedule-enddate').val(format_date(end, settings.date_format));
       freebusy_ui.endtime = $('#schedule-endtime').val(format_date(end, settings.time_format)).show();
       
       if (allday.checked) {
         freebusy_ui.starttime.val("12:00").hide();
         freebusy_ui.endtime.val("13:00").hide();
         event.allDay = true;
       }
       
       // read attendee roles from drop-downs
       $('select.edit-attendee-role').each(function(i, elem){
         if (event_attendees[i])
           event_attendees[i].role = $(elem).val();
       });
       
       // render time slots
       var now = new Date(), fb_start = new Date(), fb_end = new Date();
       fb_start.setTime(event.start);
       fb_start.setHours(0); fb_start.setMinutes(0); fb_start.setSeconds(0); fb_start.setMilliseconds(0);
       fb_end.setTime(fb_start.getTime() + DAY_MS);
       
       freebusy_data = { required:{}, all:{} };
       freebusy_ui.loading = 1;  // prevent render_freebusy_grid() to load data yet
       freebusy_ui.numdays = Math.max(allday.checked ? 14 : 1, Math.ceil(duration * 2 / 86400));
       freebusy_ui.interval = allday.checked ? 1440 : (60 / (settings.timeslots || 1));
       freebusy_ui.start = fb_start;
       freebusy_ui.end = new Date(freebusy_ui.start.getTime() + DAY_MS * freebusy_ui.numdays);
       render_freebusy_grid(0);
       
       // render list of attendees
       freebusy_ui.attendees = {};
       var domid, dispname, data, role_html, list_html = '';
       for (var i=0; i < event_attendees.length; i++) {
         data = event_attendees[i];
         dispname = Q(data.name || data.email);
         domid = String(data.email).replace(rcmail.identifier_expr, '');
         role_html = '<a class="attendee-role-toggle" id="rcmlia' + domid + '" title="' + Q(rcmail.gettext('togglerole', 'calendar')) + '">&nbsp;</a>';
         list_html += '<div class="attendee ' + String(data.role).toLowerCase() + '" id="rcmli' + domid + '">' + role_html + dispname + '</div>';
         
         // clone attendees data for local modifications
         freebusy_ui.attendees[i] = freebusy_ui.attendees[domid] = $.extend({}, data);
       }
       
       // add total row
       list_html += '<div class="attendee spacer">&nbsp;</div>';
       list_html += '<div class="attendee total">' + rcmail.gettext('reqallattendees','calendar') + '</div>';
       
       $('#schedule-attendees-list').html(list_html)
         .unbind('click.roleicons')
         .bind('click.roleicons', function(e){
           // toggle attendee status upon click on icon
           if (e.target.id && e.target.id.match(/rcmlia(.+)/)) {
             var attendee, domid = RegExp.$1,
                 roles = [ 'REQ-PARTICIPANT', 'OPT-PARTICIPANT', 'NON-PARTICIPANT', 'CHAIR' ];
             if ((attendee = freebusy_ui.attendees[domid]) && attendee.role != 'ORGANIZER') {
               var req = attendee.role != 'OPT-PARTICIPANT' && attendee.role != 'NON-PARTICIPANT';
               var j = $.inArray(attendee.role, roles);
               j = (j+1) % roles.length;
               attendee.role = roles[j];
               $(e.target).parent().attr('class', 'attendee '+String(attendee.role).toLowerCase());
               
               // update total display if required-status changed
               if (req != (roles[j] != 'OPT-PARTICIPANT' && roles[j] != 'NON-PARTICIPANT')) {
                 compute_freebusy_totals();
                 update_freebusy_display(attendee.email);
               }
             }
           }
           
           return false;
         });
       
       // enable/disable buttons
       // FIXME: .button() does nothing in Elastic skin
       var disabled = fb_start.getTime() < now.getTime();
       $('#schedule-find-prev').button('option', 'disabled', disabled).prop('disabled', disabled);
       
       // dialog buttons
       var buttons = [
         {
           text: rcmail.gettext('select', 'calendar'),
           'class': 'save mainaction',
           click: function() {
             $('#edit-startdate').val(freebusy_ui.startdate.val());
             $('#edit-starttime').val(freebusy_ui.starttime.val());
             $('#edit-enddate').val(freebusy_ui.enddate.val());
             $('#edit-endtime').val(freebusy_ui.endtime.val());
 
             // write role changes back to main dialog
             $('select.edit-attendee-role').each(function(i, elem){
               if (event_attendees[i] && freebusy_ui.attendees[i]) {
                 event_attendees[i].role = freebusy_ui.attendees[i].role;
                 $(elem).val(event_attendees[i].role);
               }
             });
 
             if (freebusy_ui.needsupdate)
               update_freebusy_status(me.selected_event);
             freebusy_ui.needsupdate = false;
             $dialog.dialog("close");
           }
         },
         {
           text: rcmail.gettext('cancel', 'calendar'),
           'class': 'cancel',
           click: function() { $dialog.dialog("close"); }
         }
       ];
 
       $dialog.dialog({
         modal: true,
         resizable: true,
         closeOnEscape: true,
         title: rcmail.gettext('scheduletime', 'calendar'),
         open: function() {
           rcmail.ksearch_blur();
           $dialog.attr('aria-hidden', 'false').find('#schedule-find-next, #schedule-find-prev').not(':disabled').first().focus();
         },
         close: function() {
           $dialog.dialog("destroy").attr('aria-hidden', 'true').hide();
           // TODO: focus opener button
         },
         resizeStop: function() {
           render_freebusy_overlay();
         },
         buttons: buttons,
         minWidth: 640,
         width: 850
       }).show();
       
       // adjust dialog size to fit grid without scrolling
       var gridw = $('#schedule-freebusy-times').width();
       var overflow = gridw - $('#attendees-freebusy-table td.times').width();
       me.dialog_resize($dialog.get(0), $dialog.height() + (bw.ie ? 20 : 0), 800 + Math.max(0, overflow));
       
       // fetch data from server
       freebusy_ui.loading = 0;
       load_freebusy_data(freebusy_ui.start, freebusy_ui.interval);
     };
 
     // render an HTML table showing free-busy status for all the event attendees
     var render_freebusy_grid = function(delta)
     {
       if (delta) {
         freebusy_ui.start.setTime(freebusy_ui.start.getTime() + DAY_MS * delta);
         fix_date(freebusy_ui.start);
         
         // skip weekends if in workinhoursonly-mode
         if (Math.abs(delta) == 1 && freebusy_ui.workinhoursonly) {
           while (is_weekend(freebusy_ui.start))
             freebusy_ui.start.setTime(freebusy_ui.start.getTime() + DAY_MS * delta);
           fix_date(freebusy_ui.start);
         }
         
         freebusy_ui.end = new Date(freebusy_ui.start.getTime() + DAY_MS * freebusy_ui.numdays);
       }
       
       var dayslots = Math.floor(1440 / freebusy_ui.interval);
       var date_format = 'ddd '+ (dayslots <= 2 ? settings.date_short : settings.date_format);
       var lastdate, datestr, css,
         curdate = new Date(),
         allday = (freebusy_ui.interval == 1440),
         interval = allday ? 1440 : (freebusy_ui.interval * (settings.timeslots || 1));
         times_css = (allday ? 'allday ' : ''),
         dates_row = '<tr class="dates">',
         times_row = '<tr class="times">',
         slots_row = '';
 
       for (var s = 0, t = freebusy_ui.start.getTime(); t < freebusy_ui.end.getTime(); s++) {
         curdate.setTime(t);
         datestr = format_date(curdate, date_format);
         if (datestr != lastdate) {
           if (lastdate && !allday) break;
           dates_row += '<th colspan="' + dayslots + '" class="boxtitle date' + format_date(curdate, 'DDMMYYYY') + '">' + Q(datestr) + '</th>';
           lastdate = datestr;
         }
         
         // set css class according to working hours
         css = is_weekend(curdate) || (freebusy_ui.interval <= 60 && !is_workinghour(curdate)) ? 'offhours' : 'workinghours';
         times_row += '<td class="' + times_css + css + '" id="t-' + Math.floor(t/1000) + '">' + Q(allday ? rcmail.gettext('all-day','calendar') : format_date(curdate, settings.time_format)) + '</td>';
         slots_row += '<td class="' + css + '">&nbsp;</td>';
         
         t += interval * 60000;
       }
       dates_row += '</tr>';
       times_row += '</tr>';
       
       // render list of attendees
       var domid, data, list_html = '', times_html = '';
       for (var i=0; i < event_attendees.length; i++) {
         data = event_attendees[i];
         domid = String(data.email).replace(rcmail.identifier_expr, '');
         times_html += '<tr id="fbrow' + domid + '" class="fbcontent">' + slots_row + '</tr>';
       }
       
       // add line for all/required attendees
       times_html += '<tr class="spacer"><td colspan="' + (dayslots * freebusy_ui.numdays) + '"></td>';
       times_html += '<tr id="fbrowall" class="fbcontent">' + slots_row + '</tr>';
       
       var table = $('#schedule-freebusy-times');
       table.children('thead').html(dates_row + times_row);
       table.children('tbody').html(times_html);
       
       // initialize event handlers on grid
       if (!freebusy_ui.grid_events) {
         freebusy_ui.grid_events = true;
         table.children('thead').click(function(e){
           // move event to the clicked date/time
           if (e.target.id && e.target.id.match(/t-(\d+)/)) {
             var newstart = new Date(RegExp.$1 * 1000);
             // set time to 00:00
             if (me.selected_event.allDay) {
               newstart.setMinutes(0);
               newstart.setHours(0);
             }
             update_freebusy_dates(newstart, new Date(newstart.getTime() + freebusy_ui.startdate.data('duration') * 1000));
             render_freebusy_overlay();
           }
         });
       }
       
       // if we have loaded free-busy data, show it
       if (!freebusy_ui.loading) {
         if (freebusy_ui.start < freebusy_data.start || freebusy_ui.end > freebusy_data.end || freebusy_ui.interval != freebusy_data.interval) {
           load_freebusy_data(freebusy_ui.start, freebusy_ui.interval);
         }
         else {
           for (var email, i=0; i < event_attendees.length; i++) {
             if ((email = event_attendees[i].email))
               update_freebusy_display(email);
           }
         }
       }
       
       // render current event date/time selection over grid table
       // use timeout to let the dom attributes (width/height/offset) be set first
       window.setTimeout(function(){ render_freebusy_overlay(); }, 10);
     };
     
     // render overlay element over the grid to visiualize the current event date/time
     var render_freebusy_overlay = function()
     {
       var overlay = $('#schedule-event-time');
       if (me.selected_event.end.getTime() <= freebusy_ui.start.getTime() || me.selected_event.start.getTime() >= freebusy_ui.end.getTime()) {
         overlay.hide();
         if (overlay.data('isdraggable'))
           overlay.draggable('disable');
       }
       else {
         var i, n, table = $('#schedule-freebusy-times'),
           width = 0,
           pos = { top:table.children('thead').height(), left:0 },
           eventstart = date2unixtime(clone_date(me.selected_event.start, me.selected_event.allDay?1:0)),
           eventend = date2unixtime(clone_date(me.selected_event.end, me.selected_event.allDay?2:0)) - 60,
           slotstart = date2unixtime(freebusy_ui.start),
           slotsize = freebusy_ui.interval * 60,
           slotnum = freebusy_ui.interval > 60 ? 1 : (60 / freebusy_ui.interval),
           cells = table.children('thead').find('td'),
           cell_width = cells.first().get(0).offsetWidth,
           h_margin = table.parents('table').data('h-margin'),
           v_margin = table.parents('table').data('v-margin'),
           slotend;
 
         if (h_margin === undefined)
           h_margin = 4;
         if (v_margin === undefined)
           v_margin = 4;
 
         // iterate through slots to determine position and size of the overlay
         for (i=0; i < cells.length; i++) {
           for (n=0; n < slotnum; n++) {
             slotend = slotstart + slotsize - 1;
             // event starts in this slot: compute left
             if (eventstart >= slotstart && eventstart <= slotend) {
               pos.left = Math.round(i * cell_width + (cell_width / slotnum) * n);
             }
             // event ends in this slot: compute width
             if (eventend >= slotstart && eventend <= slotend) {
               width = Math.round(i * cell_width + (cell_width / slotnum) * (n + 1)) - pos.left;
             }
             slotstart += slotsize;
           }
         }
 
         if (!width)
           width = table.width() - pos.left;
 
         // overlay is visible
         if (width > 0) {
           overlay.css({
             width: (width - h_margin) + 'px',
             height: (table.children('tbody').height() - v_margin) + 'px',
             left: pos.left + 'px',
             top: pos.top + 'px'
           }).show();
 
           // configure draggable
           if (!overlay.data('isdraggable')) {
             overlay.draggable({
               axis: 'x',
               scroll: true,
               stop: function(e, ui){
                 // convert pixels to time
                 var px = ui.position.left;
                 var range_p = $('#schedule-freebusy-times').width();
                 var range_t = freebusy_ui.end.getTime() - freebusy_ui.start.getTime();
                 var newstart = new Date(freebusy_ui.start.getTime() + px * (range_t / range_p));
                 newstart.setSeconds(0); newstart.setMilliseconds(0);
                 // snap to day boundaries
                 if (me.selected_event.allDay) {
                   if (newstart.getHours() >= 12)  // snap to next day
                     newstart.setTime(newstart.getTime() + DAY_MS);
                   newstart.setMinutes(0);
                   newstart.setHours(0);
                 }
                 else {
                   // round to 5 minutes
                   // @TODO: round to timeslots?
                   var round = newstart.getMinutes() % 5;
                   if (round > 2.5) newstart.setTime(newstart.getTime() + (5 - round) * 60000);
                   else if (round > 0) newstart.setTime(newstart.getTime() - round * 60000);
                 }
                 // update event times and display
                 update_freebusy_dates(newstart, new Date(newstart.getTime() + freebusy_ui.startdate.data('duration') * 1000));
                 if (me.selected_event.allDay)
                   render_freebusy_overlay();
               }
             }).data('isdraggable', true);
           }
           else
             overlay.draggable('enable');
         }
         else
           overlay.draggable('disable').hide();
       }
     };
 
     // fetch free-busy information for each attendee from server
     var load_freebusy_data = function(from, interval)
     {
       var start = new Date(from.getTime() - DAY_MS * 2);  // start 2 days before event
       fix_date(start);
       var end = new Date(start.getTime() + DAY_MS * Math.max(14, freebusy_ui.numdays + 7));   // load min. 14 days
       freebusy_ui.numrequired = 0;
       freebusy_data.all = [];
       freebusy_data.required = [];
 
       // load free-busy information for every attendee
       var domid, email;
       for (var i=0; i < event_attendees.length; i++) {
         if ((email = event_attendees[i].email)) {
           domid = String(email).replace(rcmail.identifier_expr, '');
           $('#rcmli' + domid).addClass('loading');
           freebusy_ui.loading++;
           
           $.ajax({
             type: 'GET',
             dataType: 'json',
             url: rcmail.url('freebusy-times'),
             data: { email:email, start:date2servertime(clone_date(start, 1)), end:date2servertime(clone_date(end, 2)), interval:interval, _remote:1 },
             success: function(data) {
               freebusy_ui.loading--;
               
               // find attendee
               var i, attendee = null;
               for (i=0; i < event_attendees.length; i++) {
                 if (freebusy_ui.attendees[i].email == data.email) {
                   attendee = freebusy_ui.attendees[i];
                   break;
                 }
               }
               
               // copy data to member var
               var ts, status,
                 req = attendee.role != 'OPT-PARTICIPANT',
                 start = parseISO8601(data.start);
 
               freebusy_data.start = new Date(start);
               freebusy_data.end = parseISO8601(data.end);
               freebusy_data.interval = data.interval;
               freebusy_data[data.email] = {};
 
               for (i=0; i < data.slots.length; i++) {
                 ts = date2timestring(start, data.interval > 60);
                 status = data.slots.charAt(i);
                 freebusy_data[data.email][ts] = status
                 start = new Date(start.getTime() + data.interval * 60000);
                 
                 // set totals
                 if (!freebusy_data.required[ts])
                   freebusy_data.required[ts] = [0,0,0,0];
                 if (req)
                   freebusy_data.required[ts][status]++;
                 
                 if (!freebusy_data.all[ts])
                   freebusy_data.all[ts] = [0,0,0,0];
                 freebusy_data.all[ts][status]++;
               }
 
               // hide loading indicator
               var domid = String(data.email).replace(rcmail.identifier_expr, '');
               $('#rcmli' + domid).removeClass('loading');
               
               // update display
               update_freebusy_display(data.email);
             }
           });
           
           // count required attendees
           if (freebusy_ui.attendees[i].role != 'OPT-PARTICIPANT')
             freebusy_ui.numrequired++;
         }
       }
     };
     
     // re-calculate total status after role change
     var compute_freebusy_totals = function()
     {
       freebusy_ui.numrequired = 0;
       freebusy_data.all = [];
       freebusy_data.required = [];
       
       var email, req, status;
       for (var i=0; i < event_attendees.length; i++) {
         if (!(email = event_attendees[i].email))
           continue;
         
         req = freebusy_ui.attendees[i].role != 'OPT-PARTICIPANT';
         if (req)
           freebusy_ui.numrequired++;
         
         for (var ts in freebusy_data[email]) {
           if (!freebusy_data.required[ts])
             freebusy_data.required[ts] = [0,0,0,0];
           if (!freebusy_data.all[ts])
             freebusy_data.all[ts] = [0,0,0,0];
           
           status = freebusy_data[email][ts];
           freebusy_data.all[ts][status]++;
           
           if (req)
             freebusy_data.required[ts][status]++;
         }
       }
     };
 
     // update free-busy grid with status loaded from server
     var update_freebusy_display = function(email)
     {
       var status_classes = ['unknown','free','busy','tentative','out-of-office'];
       var domid = String(email).replace(rcmail.identifier_expr, '');
       var row = $('#fbrow' + domid);
       var rowall = $('#fbrowall').children();
       var dateonly = freebusy_ui.interval > 60,
         t, ts = date2timestring(freebusy_ui.start, dateonly),
         curdate = new Date(),
         fbdata = freebusy_data[email];
 
       if (fbdata && fbdata[ts] !== undefined && row.length) {
         t = freebusy_ui.start.getTime();
         row.children().each(function(i, cell) {
           var j, n, attr, last, all_slots = [], slots = [],
             all_cell = rowall.get(i),
             cnt = dateonly ? 1 : (60 / freebusy_ui.interval),
             percent = (100 / cnt);
 
           for (n=0; n < cnt; n++) {
             curdate.setTime(t);
             ts = date2timestring(curdate, dateonly);
             attr = {
               'style': 'float:left; width:' + percent.toFixed(2) + '%',
               'class': fbdata[ts] ? status_classes[fbdata[ts]] : 'unknown'
             };
 
             slots.push($('<div>').attr(attr));
 
             // also update total row if all data was loaded
             if (!freebusy_ui.loading && freebusy_data.all[ts] && all_cell) {
               var w, all_status = freebusy_data.all[ts][2] ? 'busy' : 'unknown',
                 req_status = freebusy_data.required[ts][2] ? 'busy' : 'free';
 
               for (j=1; j < status_classes.length; j++) {
                 if (freebusy_ui.numrequired && freebusy_data.required[ts][j] >= freebusy_ui.numrequired)
                   req_status = status_classes[j];
                 if (freebusy_data.all[ts][j] == event_attendees.length)
                   all_status = status_classes[j];
               }
 
               attr['class'] = req_status + ' all-' + all_status;
 
               // these elements use some specific styling, so we want to minimize their number
               if (last && last.attr('class').startsWith(attr['class'])) {
                 w = percent + parseFloat(last.css('width').replace('%', ''));
                 last.css('width', w.toFixed(2) + '%').attr('class', attr['class'] + ' w' + w.toFixed(0));
               }
               else {
                 last = $('<div>').attr(attr).addClass('w' + percent.toFixed(0)).append('<span>');
                 all_slots.push(last);
               }
             }
 
             t += freebusy_ui.interval * 60000;
           }
 
           $(cell).html('').append(slots);
           if (all_slots.length)
             $(all_cell).html('').append(all_slots);
         });
       }
     };
     
     // write changed event date/times back to form fields
     var update_freebusy_dates = function(start, end)
     {
       // fix all-day evebt times
       if (me.selected_event.allDay) {
         var numdays = Math.floor((me.selected_event.end.getTime() - me.selected_event.start.getTime()) / DAY_MS);
         start.setHours(12);
         start.setMinutes(0);
         end.setTime(start.getTime() + numdays * DAY_MS);
         end.setHours(13);
         end.setMinutes(0);
       }
       me.selected_event.start = start;
       me.selected_event.end = end;
       freebusy_ui.startdate.val(format_date(start, settings.date_format));
       freebusy_ui.starttime.val(format_date(start, settings.time_format));
       freebusy_ui.enddate.val(format_date(end, settings.date_format));
       freebusy_ui.endtime.val(format_date(end, settings.time_format));
       freebusy_ui.needsupdate = true;
     };
 
     // attempt to find a time slot where all attemdees are available
     var freebusy_find_slot = function(dir)
     {
       // exit if free-busy data isn't available yet
       if (!freebusy_data || !freebusy_data.start)
         return false;
 
       var event = me.selected_event,
         eventstart = clone_date(event.start, event.allDay ? 1 : 0).getTime(),  // calculate with integers
         eventend = clone_date(event.end, event.allDay ? 2 : 0).getTime(),
         duration = eventend - eventstart - (event.allDay ? HOUR_MS : 0),  /* make sure we don't cross day borders on DST change */
         sinterval = freebusy_data.interval * 60000,
         intvlslots = 1,
         numslots = Math.ceil(duration / sinterval),
         fb_start = freebusy_data.start.getTime(),
         fb_end = freebusy_data.end.getTime(),
         checkdate, slotend, email, ts, slot, slotdate = new Date(),
         candidatecount = 0, candidatestart = false, success = false;
 
       // shift event times to next possible slot
       eventstart += sinterval * intvlslots * dir;
       eventend += sinterval * intvlslots * dir;
 
       // iterate through free-busy slots and find candidates
       for (slot = dir > 0 ? fb_start : fb_end - sinterval;
             (dir > 0 && slot < fb_end) || (dir < 0 && slot >= fb_start);
             slot += sinterval * dir
       ) {
         slotdate.setTime(slot);
         // fix slot if just crossed a DST change
         if (event.allDay) {
           fix_date(slotdate);
           slot = slotdate.getTime();
         }
         slotend = slot + sinterval;
 
         if ((dir > 0 && slotend <= eventstart) || (dir < 0 && slot >= eventend))  // skip
           continue;
 
         // respect workinghours setting
         if (freebusy_ui.workinhoursonly) {
           if (is_weekend(slotdate) || (freebusy_data.interval <= 60 && !is_workinghour(slotdate))) {  // skip off-hours
             candidatestart = false;
             candidatecount = 0;
             continue;
           }
         }
 
         if (!candidatestart)
           candidatestart = slot;
 
         ts = date2timestring(slotdate, freebusy_data.interval > 60);
 
         // check freebusy data for all attendees
         for (var i=0; i < event_attendees.length; i++) {
           if (freebusy_ui.attendees[i].role != 'OPT-PARTICIPANT' && (email = freebusy_ui.attendees[i].email) && freebusy_data[email] && freebusy_data[email][ts] > 1) {
             candidatestart = false;
             break;
           }
         }
         
         // occupied slot
         if (!candidatestart) {
           slot += Math.max(0, intvlslots - candidatecount - 1) * sinterval * dir;
           candidatecount = 0;
           continue;
         }
         else if (dir < 0)
           candidatestart = slot;
         
         candidatecount++;
         
         // if candidate is big enough, this is it!
         if (candidatecount == numslots) {
           event.start.setTime(candidatestart);
           event.end.setTime(candidatestart + duration);
           success = true;
           break;
         }
       }
 
       // update event date/time display
       if (success) {
         update_freebusy_dates(event.start, event.end);
         
         // move freebusy grid if necessary
         var offset = Math.ceil((event.start.getTime() - freebusy_ui.end.getTime()) / DAY_MS);
         if (event.start.getTime() >= freebusy_ui.end.getTime())
           render_freebusy_grid(Math.max(1, offset));
         else if (event.end.getTime() <= freebusy_ui.start.getTime())
           render_freebusy_grid(Math.min(-1, offset));
         else
           render_freebusy_overlay();
 
         var now = new Date(), disabled = event.start.getTime() < now.getTime();
         // FIXME: .button() does nothing in Elastic skin
         $('#schedule-find-prev').button('option', 'disabled', disabled).prop('disabled', disabled);
 
         // speak new selection
         rcmail.display_message(rcmail.gettext('suggestedslot', 'calendar') + ': ' + me.event_date_text(event, true), 'voice');
       }
       else {
         rcmail.alert_dialog(rcmail.gettext('noslotfound','calendar'));
       }
     };
 
     // update event properties and attendees availability if event times have changed
     var event_times_changed = function()
     {
       if (me.selected_event) {
         var allday = $('#edit-allday').get(0);
         me.selected_event.allDay = allday.checked;
         me.selected_event.start = me.parse_datetime(allday.checked ? '12:00' : $('#edit-starttime').val(), $('#edit-startdate').val());
         me.selected_event.end   = me.parse_datetime(allday.checked ? '13:00' : $('#edit-endtime').val(), $('#edit-enddate').val());
         if (event_attendees)
           freebusy_ui.needsupdate = true;
         $('#edit-startdate').data('duration', Math.round((me.selected_event.end.getTime() - me.selected_event.start.getTime()) / 1000));
       }
     };
 
     // add the given list of participants
     var add_attendees = function(names, params)
     {
       names = explode_quoted_string(names.replace(/,\s*$/, ''), ',');
 
       // parse name/email pairs
       var item, email, name, success = false;
       for (var i=0; i < names.length; i++) {
         email = name = '';
         item = $.trim(names[i]);
         
         if (!item.length) {
           continue;
         } // address in brackets without name (do nothing)
         else if (item.match(/^<[^@]+@[^>]+>$/)) {
           email = item.replace(/[<>]/g, '');
         } // address without brackets and without name (add brackets)
         else if (rcube_check_email(item)) {
           email = item;
         } // address with name
         else if (item.match(/([^\s<@]+@[^>]+)>*$/)) {
           email = RegExp.$1;
           name = item.replace(email, '').replace(/^["\s<>]+/, '').replace(/["\s<>]+$/, '');
         }
         if (email) {
           add_attendee($.extend({ email:email, name:name }, params));
           success = true;
         }
         else {
           rcmail.alert_dialog(rcmail.gettext('noemailwarning'));
         }
       }
       
       return success;
     };
 
     // add the given attendee to the list
     var add_attendee = function(data, readonly, before)
     {
       if (!me.selected_event)
         return false;
 
       // check for dupes...
       var exists = false;
       $.each(event_attendees, function(i, v){ exists |= (v.email == data.email); });
       if (exists)
         return false;
 
       var calendar = me.selected_event && me.calendars[me.selected_event.calendar] ? me.calendars[me.selected_event.calendar] : me.calendars[me.selected_calendar];
 
       var dispname = Q(data.name || data.email);
       dispname = '<span' + ((data.email && data.email != dispname) ? ' title="' + Q(data.email) + '"' : '') + '>' + dispname + '</span>';
 
       // role selection
       var organizer = data.role == 'ORGANIZER';
       var opts = {};
       if (organizer)
         opts.ORGANIZER = rcmail.gettext('calendar.roleorganizer');
       opts['REQ-PARTICIPANT'] = rcmail.gettext('calendar.rolerequired');
       opts['OPT-PARTICIPANT'] = rcmail.gettext('calendar.roleoptional');
       opts['NON-PARTICIPANT'] = rcmail.gettext('calendar.rolenonparticipant');
 
       if (data.cutype != 'RESOURCE')
         opts['CHAIR'] =  rcmail.gettext('calendar.rolechair');
 
       if (organizer && !readonly)
         dispname = rcmail.env['identities-selector'];
 
       var select = '<select class="edit-attendee-role form-control custom-select"'
         + (organizer || readonly ? ' disabled="true"' : '')
         + ' aria-label="' + rcmail.gettext('role','calendar') + '">';
       for (var r in opts)
         select += '<option value="'+ r +'" class="' + r.toLowerCase() + '"' + (data.role == r ? ' selected="selected"' : '') +'>' + Q(opts[r]) + '</option>';
       select += '</select>';
 
       // delete icon
       var icon = rcmail.env.deleteicon ? '<img src="' + rcmail.env.deleteicon + '" alt="" />' : '<span class="inner">' + Q(rcmail.gettext('delete')) + '</span>';
       var dellink = '<a href="#delete" class="iconlink icon button delete deletelink" title="' + Q(rcmail.gettext('delete')) + '">' + icon + '</a>';
       var tooltip = '', status = (data.status || '').toLowerCase(),
         status_label = rcmail.gettext('status' + status, 'libcalendaring');
 
       // send invitation checkbox
       var invbox = '<input type="checkbox" class="edit-attendee-reply" value="' + Q(data.email) +'" title="' + Q(rcmail.gettext('calendar.sendinvitations')) + '" '
         + (!data.noreply && settings.itip_notify & 1 ? 'checked="checked" ' : '') + '/>';
 
       if (data['delegated-to'])
         tooltip = rcmail.gettext('libcalendaring.delegatedto') + ' ' + data['delegated-to'];
       else if (data['delegated-from'])
         tooltip = rcmail.gettext('libcalendaring.delegatedfrom') + ' ' + data['delegated-from'];
       else if (!status && organizer)
         tooltip = rcmail.gettext('statusorganizer', 'libcalendaring');
       else if (status)
         tooltip = status_label;
 
       // add expand button for groups
       if (data.cutype == 'GROUP') {
         dispname += ' <a href="#expand" data-email="' + Q(data.email) + '" class="iconbutton add expandlink" title="' + rcmail.gettext('expandattendeegroup','libcalendaring') + '">' +
           rcmail.gettext('expandattendeegroup','libcalendaring') + '</a>';
       }
 
       var avail = data.email ? 'loading' : 'unknown';
       var table = rcmail.env.calendar_resources && data.cutype == 'RESOURCE' ? resources_list : attendees_list;
       var img_src = rcmail.assets_path('program/resources/blank.gif');
       var elastic = $(table).parents('.no-img').length > 0;
       var avail_tag = elastic ? ('<span class="' + avail + '"') : ('<img alt="" src="' + img_src + '" class="availabilityicon '  + avail + '"');
       var html = '<td class="role">' + select + '</td>' +
         '<td class="name"><span class="attendee-name">' + dispname + '</span></td>' +
         '<td class="availability">' + avail_tag + ' data-email="' + data.email + '" /></td>' +
         '<td class="confirmstate"><span class="attendee ' + (status || 'organizer') + '" title="' + Q(tooltip) + '">' + Q(status && !elastic ? status_label : '') + '</span></td>' +
         (data.cutype != 'RESOURCE' ? '<td class="invite">' + (organizer || readonly || !invbox ? '' : invbox) + '</td>' : '') +
         '<td class="options">' + (organizer || readonly ? '' : dellink) + '</td>';
 
       var tr = $('<tr>')
         .addClass(String(data.role).toLowerCase())
         .html(html);
 
       if (before)
         tr.insertBefore(before)
       else
         tr.appendTo(table);
 
       tr.find('a.deletelink').click({ id:(data.email || data.name) }, function(e) { remove_attendee(this, e.data.id); return false; });
       tr.find('a.expandlink').click(data, function(e) { me.expand_attendee_group(e, add_attendee, remove_attendee); return false; });
       tr.find('input.edit-attendee-reply').click(function() {
         var enabled = $('#edit-attendees-invite:checked').length || $('input.edit-attendee-reply:checked').length;
         $('#eventedit .attendees-commentbox')[enabled ? 'show' : 'hide']();
       });
 
       // select organizer identity
       if (data.identity_id)
         $('#edit-identities-list').val(data.identity_id);
 
       // check free-busy status
       if (avail == 'loading') {
         check_freebusy_status(tr.find('.availability > *:first'), data.email, me.selected_event);
       }
 
       // Make Elastic checkboxes pretty
       if (window.UI && UI.pretty_checkbox) {
         $(tr).find('input[type=checkbox]').each(function() { UI.pretty_checkbox(this); });
         $(tr).find('select').each(function() { UI.pretty_select(this); });
       }
 
       event_attendees.push(data);
       return true;
     };
 
     // iterate over all attendees and update their free-busy status display
     var update_freebusy_status = function(event)
     {
       attendees_list.find('.availability > *').each(function(i,v) {
         var email, icon = $(this);
         if (email = icon.attr('data-email'))
           check_freebusy_status(icon, email, event);
       });
       
       freebusy_ui.needsupdate = false;
     };
     
     // load free-busy status from server and update icon accordingly
     var check_freebusy_status = function(icon, email, event)
     {
       var calendar = event.calendar && me.calendars[event.calendar] ? me.calendars[event.calendar] : { freebusy:false };
       if (!calendar.freebusy) {
         $(icon).attr('class', 'availabilityicon unknown');
         return;
       }
       
       icon = $(icon).attr('class', 'availabilityicon loading');
       
       $.ajax({
         type: 'GET',
         dataType: 'html',
         url: rcmail.url('freebusy-status'),
         data: { email:email, start:date2servertime(clone_date(event.start, event.allDay?1:0)), end:date2servertime(clone_date(event.end, event.allDay?2:0)), _remote: 1 },
         success: function(status){
           var avail = String(status).toLowerCase();
           icon.removeClass('loading').addClass(avail).attr('title', rcmail.gettext('avail' + avail, 'calendar'));
         },
         error: function(){
           icon.removeClass('loading').addClass('unknown').attr('title', rcmail.gettext('availunknown', 'calendar'));
         }
       });
     };
     
     // remove an attendee from the list
     var remove_attendee = function(elem, id)
     {
       $(elem).closest('tr').remove();
       event_attendees = $.grep(event_attendees, function(data){ return (data.name != id && data.email != id) });
     };
 
     // open a dialog to display detailed free-busy information and to find free slots
     var event_resources_dialog = function(search)
     {
       var $dialog = $('#eventresourcesdialog');
 
       if ($dialog.is(':ui-dialog'))
         $dialog.dialog('close');
 
       // dialog buttons
       var buttons = [
         {
           text: rcmail.gettext('addresource', 'calendar'),
           'class': 'mainaction save',
           click: function() { rcmail.command('add-resource'); $dialog.dialog("close"); }
         },
         {
           text: rcmail.gettext('close'),
           'class': 'cancel',
           click: function() { $dialog.dialog("close"); }
         }
       ];
 
       var resize = function() {
         var container = $(rcmail.gui_objects.resourceinfocalendar);
         container.fullCalendar('option', 'height', container.height() + 1);
       };
 
       // open jquery UI dialog
       $dialog.dialog({
         modal: true,
         resizable: false, // prevents from Availability tab reflow bugs on resize
         closeOnEscape: true,
         title: rcmail.gettext('findresources', 'calendar'),
         classes: {'ui-dialog': 'selection-dialog resources-dialog'},
         open: function() {
           rcmail.ksearch_blur();
           $dialog.attr('aria-hidden', 'false');
 
           // for Elastic
           if ($('html.layout-small,html.layout-phone').length) {
             $('#eventresourcesdialog .resource-selection').css('display', 'flex');
             $('#eventresourcesdialog .resource-content').css('display', 'none');
           }
           setTimeout(resize, 50);
         },
         close: function() {
           $dialog.dialog('destroy').attr('aria-hidden', 'true').hide();
         },
         resize: resize,
         buttons: buttons,
         width: 900,
         height: 500
       }).show();
 
       $('.ui-dialog-buttonset .ui-button', $dialog.parent()).first().attr('id', 'rcmbtncalresadd');
 
       me.dialog_resize($dialog.get(0), 540, Math.min(1000, $(window).width() - 50));
 
       // set search query
       $('#resourcesearchbox').val(search || '');
 
       // initialize the treelist widget
       if (!resources_treelist) {
         resources_treelist = new rcube_treelist_widget(rcmail.gui_objects.resourceslist, {
           id_prefix: 'rcres',
           id_encode: rcmail.html_identifier_encode,
           id_decode: rcmail.html_identifier_decode,
           selectable: true,
           save_state: true
         });
         resources_treelist.addEventListener('select', function(node) {
           if (resources_data[node.id]) {
             resource_showinfo(resources_data[node.id]);
             rcmail.enable_command('add-resource', me.selected_event && $("#eventedit").is(':visible') ? true : false);
 
             // on elastic mobile display resource info box
             if ($('html.layout-small,html.layout-phone').length) {
               $('#eventresourcesdialog .resource-selection').css('display', 'none');
               $('#eventresourcesdialog .resource-content').css('display', 'flex');
               $(window).resize();
               resize();
             }
           }
           else {
             rcmail.enable_command('add-resource', false);
             $(rcmail.gui_objects.resourceinfo).hide();
             $(rcmail.gui_objects.resourceownerinfo).hide();
             $(rcmail.gui_objects.resourceinfocalendar).fullCalendar('removeEventSource', resources_events_source);
           }
         });
 
         // fetch (all) resource data from server
         me.loading_lock = rcmail.set_busy(true, 'loading', me.loading_lock);
         rcmail.http_request('resources-list', {}, me.loading_lock);
 
         // register button
         rcmail.register_button('add-resource', 'rcmbtncalresadd', 'uibutton');
 
         // initialize resource calendar display
         var resource_cal = $(rcmail.gui_objects.resourceinfocalendar);
         resource_cal.fullCalendar($.extend({}, fullcalendar_defaults, {
           header: { left: '', center: '', right: '' },
           height: resource_cal.height() + 4,
           defaultView: 'agendaWeek',
           eventSources: [],
           slotMinutes: 60,
           allDaySlot: false,
           eventRender: function(event, element, view) {
             var title = rcmail.get_label(event.status, 'calendar');
             element.addClass('status-' + event.status);
             element.find('.fc-title').text(title);
             element.attr('aria-label', me.event_date_text(event, true) + ': ' + title);
           }
         }));
 
         $('#resource-calendar-prev').click(function(){
           resource_cal.fullCalendar('prev');
           return false;
         });
         $('#resource-calendar-next').click(function(){
           resource_cal.fullCalendar('next');
           return false;
         });
       }
       else if (search) {
         resource_search();
       }
       else {
         resource_render_list(resources_index);
       }
 
       if (me.selected_event && me.selected_event.start) {
         $(rcmail.gui_objects.resourceinfocalendar).fullCalendar('gotoDate', me.selected_event.start);
       }
     };
 
     // render the resource details UI box
     var resource_showinfo = function(resource)
     {
       // inline function to render a resource attribute
       function render_attrib(value) {
         if (typeof value == 'boolean') {
           return value ? rcmail.get_label('yes') : rcmail.get_label('no');
         }
 
         return value;
       }
 
       if (rcmail.gui_objects.resourceinfo) {
         var tr, table = $(rcmail.gui_objects.resourceinfo).show().find('tbody').html(''),
           attribs = $.extend({ name:resource.name }, resource.attributes||{})
           attribs.description = resource.description;
 
         for (var k in attribs) {
           if (typeof attribs[k] == 'undefined')
             continue;
           table.append($('<tr>').addClass(k + ' form-group row')
             .append('<td class="title col-sm-4"><label class="col-form-label">' + Q(ucfirst(rcmail.get_label(k, 'calendar'))) + '</label></td>')
             .append('<td class="value col-sm-8 form-control-plaintext">' + text2html(render_attrib(attribs[k])) + '</td>')
           );
         }
 
         $(rcmail.gui_objects.resourceownerinfo).hide();
         $(rcmail.gui_objects.resourceinfocalendar).fullCalendar('removeEventSource', resources_events_source);
 
         if (resource.owner) {
           // display cached data
           if (resource_owners[resource.owner]) {
             resource_owner_load(resource_owners[resource.owner]);
           }
           else {
             // fetch owner data from server
             me.loading_lock = rcmail.set_busy(true, 'loading', me.loading_lock);
             rcmail.http_request('resources-owner', { _id: resource.owner }, me.loading_lock);
           }
         }
 
         // load resource calendar
         resources_events_source.url = "./?_task=calendar&_action=resources-calendar&_id="+urlencode(resource.ID);
         $(rcmail.gui_objects.resourceinfocalendar).fullCalendar('addEventSource', resources_events_source);
       }
     };
 
     // callback from server for resource listing
     var resource_data_load = function(data)
     {
       var resources_tree = {};
 
       // store data by ID
       $.each(data, function(i, rec) {
         resources_data[rec.ID] = rec;
 
         // assign parent-relations
         if (rec.members) {
           $.each(rec.members, function(j, m){
             resources_tree[m] = rec.ID;
           });
         }
       });
 
       // walk the parent-child tree to determine the depth of each node
       $.each(data, function(i, rec) {
         rec._depth = 0;
         if (resources_tree[rec.ID])
           rec.parent_id = resources_tree[rec.ID];
 
         var parent_id = resources_tree[rec.ID];
         while (parent_id) {
           rec._depth++;
           parent_id = resources_tree[parent_id];
         }
       });
 
       // sort by depth, collection and name
       data.sort(function(a,b) {
         var j = a._type == 'collection' ? 1 : 0,
             k = b._type == 'collection' ? 1 : 0,
             d = a._depth - b._depth;
         if (!d) d = (k - j);
         if (!d) d = b.name < a.name ? 1 : -1;
         return d;
       });
 
       $.each(data, function(i, rec) {
         resources_index.push(rec.ID);
       });
 
       // apply search filter...
       if ($('#resourcesearchbox').val() != '')
         resource_search();
       else  // ...or render full list
         resource_render_list(resources_index);
 
       rcmail.set_busy(false, null, me.loading_lock);
     };
 
     // renders the given list of resource records into the treelist
     var resource_render_list = function(index) {
       var rec, link;
 
       resources_treelist.reset();
 
       $.each(index, function(i, dn) {
         if (rec = resources_data[dn]) {
           link = $('<a>').attr('href', '#')
             .attr('rel', rec.ID)
             .html(Q(rec.name));
 
           resources_treelist.insert({ id:rec.ID, html:link, classes:[rec._type], collapsed:true }, rec.parent_id, false);
         }
       });
     };
 
     // callback from server for owner information display
     var resource_owner_load = function(data)
     {
       if (data) {
         // cache this!
         resource_owners[data.ID] = data;
 
         var table = $(rcmail.gui_objects.resourceownerinfo).find('tbody').html('');
 
         for (var k in data) {
           if (k == 'event' || k == 'ID')
             continue;
 
           table.append($('<tr>').addClass(k)
             .append('<td class="title">' + Q(ucfirst(rcmail.get_label(k, 'calendar'))) + '</td>')
             .append('<td class="value">' + text2html(data[k]) + '</td>')
           );
         }
 
         table.parent().show();
       }
     }
 
     // quick-filter the loaded resource data
     var resource_search = function()
     {
       var dn, rec, dataset = [],
         q = $('#resourcesearchbox').val().toLowerCase();
 
       if (q.length && resources_data) {
         // search by iterating over all resource records
         for (dn in resources_data) {
           rec = resources_data[dn];
           if ((rec.name && String(rec.name).toLowerCase().indexOf(q) >= 0)
             || (rec.email && String(rec.email).toLowerCase().indexOf(q) >= 0)
             || (rec.description && String(rec.description).toLowerCase().indexOf(q) >= 0)
           ) {
             dataset.push(rec.ID);
           }
         }
 
         resource_render_list(dataset);
 
         // select single match
         if (dataset.length == 1) {
           resources_treelist.select(dataset[0]);
         }
       }
       else {
         $('#resourcesearchbox').val('');
       }
     };
 
     // 
     var reset_resource_search = function()
     {
       $('#resourcesearchbox').val('').focus();
       resource_render_list(resources_index);
     };
 
     // 
     var add_resource2event = function()
     {
       var resource = resources_data[resources_treelist.get_selection()];
       if (resource) {
         if (add_attendee($.extend({ role:'REQ-PARTICIPANT', status:'NEEDS-ACTION', cutype:'RESOURCE' }, resource)))
           rcmail.display_message(rcmail.get_label('resourceadded', 'calendar'), 'confirmation');
       }
     }
 
     // when the user accepts or declines an event invitation
     var event_rsvp = function(response, delegate, replymode)
     {
       var btn;
       if (typeof response == 'object') {
         btn = $(response);
         response = btn.attr('rel')
       }
       else {
         btn = $('#event-rsvp input.button[rel='+response+']');
       }
 
       // show menu to select rsvp reply mode (current or all)
       if (me.selected_event && me.selected_event.recurrence && !replymode) {
         rcube_libcalendaring.itip_rsvp_recurring(btn, function(resp, mode) {
           event_rsvp(resp, null, mode);
         });
         return;
       }
 
       if (me.selected_event && me.selected_event.attendees && response) {
         // bring up delegation dialog
         if (response == 'delegated' && !delegate) {
           rcube_libcalendaring.itip_delegate_dialog(function(data) {
             data.rsvp = data.rsvp ? 1 : '';
             event_rsvp('delegated', data, replymode);
           });
           return;
         }
 
         // update attendee status
         attendees = [];
         for (var data, i=0; i < me.selected_event.attendees.length; i++) {
           data = me.selected_event.attendees[i];
           if (settings.identity.emails.indexOf(';'+String(data.email).toLowerCase()) >= 0) {
             data.status = response.toUpperCase();
             data.rsvp = 0;  // unset RSVP flag
 
             if (data.status == 'DELEGATED') {
               data['delegated-to'] = delegate.to;
               data.rsvp = delegate.rsvp
             }
             else {
               if (data['delegated-to']) {
                 delete data['delegated-to'];
                 if (data.role == 'NON-PARTICIPANT' && data.status != 'DECLINED')
                   data.role = 'REQ-PARTICIPANT';
               }
             }
 
             attendees.push(i)
           }
           else if (response != 'DELEGATED' && data['delegated-from'] &&
               settings.identity.emails.indexOf(';'+String(data['delegated-from']).toLowerCase()) >= 0) {
             delete data['delegated-from'];
           }
 
           // set free_busy status to transparent if declined (#4425)
           if (data.status == 'DECLINED' || data.role == 'NON-PARTICIPANT') {
             me.selected_event.free_busy = 'free';
           }
           else {
             me.selected_event.free_busy = 'busy';
           }
         }
 
         // submit status change to server
         var submit_data = $.extend({}, me.selected_event, { source:null, comment:$('#reply-comment-event-rsvp').val(), _savemode: replymode || 'all' }, (delegate || {})),
           noreply = $('#noreply-event-rsvp:checked').length ? 1 : 0;
 
         // import event from mail (temporary iTip event)
         if (submit_data._mbox && submit_data._uid) {
           me.saving_lock = rcmail.set_busy(true, 'calendar.savingdata');
           rcmail.http_post('mailimportitip', {
             _mbox: submit_data._mbox,
             _uid:  submit_data._uid,
             _part: submit_data._part,
             _status:  response,
             _to: (delegate ? delegate.to : null),
             _rsvp: (delegate && delegate.rsvp) ? 1 : 0,
             _noreply: noreply,
             _comment: submit_data.comment,
             _instance: submit_data._instance,
             _savemode: submit_data._savemode
           });
         }
         else if (settings.invitation_calendars) {
           update_event('rsvp', submit_data, { status:response, noreply:noreply, attendees:attendees });
         }
         else {
           me.saving_lock = rcmail.set_busy(true, 'calendar.savingdata');
           rcmail.http_post('calendar/event', { action:'rsvp', e:submit_data, status:response, attendees:attendees, noreply:noreply });
         }
 
         event_show_dialog(me.selected_event);
       }
     };
 
     // add the given date to the RDATE list
     var add_rdate = function(date)
     {
       var li = $('<li>')
         .attr('data-value', date2servertime(date))
         .append($('<span>').text(format_date(date, settings.date_format)))
         .appendTo('#edit-recurrence-rdates');
 
       $('<a>').attr('href', '#del')
         .addClass('iconbutton delete')
         .html(rcmail.get_label('delete', 'calendar'))
         .attr('title', rcmail.get_label('delete', 'calendar'))
         .appendTo(li);
     };
 
     // re-sort the list items by their 'data-value' attribute
     var sort_rdates = function()
     {
       var mylist = $('#edit-recurrence-rdates'),
         listitems = mylist.children('li').get();
       listitems.sort(function(a, b) {
          var compA = $(a).attr('data-value');
          var compB = $(b).attr('data-value');
          return (compA < compB) ? -1 : (compA > compB) ? 1 : 0;
       })
       $.each(listitems, function(idx, item) { mylist.append(item); });
     }
 
     // remove the link reference matching the given uri
     function remove_link(elem)
     {
       var $elem = $(elem), uri = $elem.attr('data-uri');
 
       me.selected_event.links = $.grep(me.selected_event.links, function(link) { return link.uri != uri; });
 
       // remove UI list item
       $elem.hide().closest('li').addClass('deleted');
     }
 
     // post the given event data to server
     var update_event = function(action, data, add)
     {
       me.saving_lock = rcmail.set_busy(true, 'calendar.savingdata');
       rcmail.http_post('calendar/event', $.extend({ action:action, e:data }, (add || {})));
 
       // render event temporarily into the calendar
       if ((data.start && data.end) || data.id) {
         var tmp, event = data.id ? $.extend(fc.fullCalendar('clientEvents', data.id)[0], data) : data;
 
         if (data.start)
           event.start = data.start;
         if (data.end)
           event.end = data.end;
         if (data.allDay !== undefined)
           event.allDay = !!data.allDay; // must be boolean for fullcalendar
 
         // For fullCalendar all-day event's end date must be exclusive
         if (event.allDay && data.end && (tmp = moment(data.end)) && tmp.format('Hms') !== '000') {
           event.end = moment().year(tmp.year()).month(tmp.month()).date(tmp.date()).hour(0).minute(0).second(0).add(1, 'days');
         }
 
         event.editable = false;
         event.temp = true;
         event.className = ['fc-event-cal-'+data.calendar, 'fc-event-temp'];
 
         fc.fullCalendar(data.id ? 'updateEvent' : 'renderEvent', event);
 
         // mark all recurring instances as temp
         if (event.recurrence || event.recurrence_id) {
           var base_id = event.recurrence_id ? event.recurrence_id : String(event.id).replace(/-\d+(T\d{6})?$/, '');
           $.each(fc.fullCalendar('clientEvents', function(e){ return e.id == base_id || e.recurrence_id == base_id; }), function(i,ev) {
             ev.temp = true;
             ev.editable = false;
             event.className.push('fc-event-temp');
             fc.fullCalendar('updateEvent', ev);
           });
         }
       }
     };
 
     // mouse-click handler to check if the show dialog is still open and prevent default action
     var dialog_check = function(e)
     {
       var showd = $("#eventshow");
       if (showd.is(':visible') && !$(e.target).closest('.ui-dialog').length && !$(e.target).closest('.popupmenu').length) {
         showd.dialog('close');
         e.stopImmediatePropagation();
         ignore_click = true;
         return false;
       }
       else if (ignore_click) {
         window.setTimeout(function(){ ignore_click = false; }, 20);
         return false;
       }
       return true;
     };
 
     // display confirm dialog when modifying/deleting an event
     var update_event_confirm = function(action, event, data)
     {
       // Allow other plugins to do actions here
       // E.g. when you move/resize the event init wasn't called
       // but we need it as some plugins may modify user identities
       // we depend on here (kolab_delegation)
       rcmail.triggerEvent('calendar-event-init', {o: event});
 
       if (!data) data = event;
       var decline = false, notify = false, html = '', cal = me.calendars[event.calendar],
         _has_attendees = me.has_attendees(event),
         _is_attendee = _has_attendees && me.is_attendee(event),
         _is_organizer = me.is_organizer(event);
 
       // event has attendees, ask whether to notify them
       if (_has_attendees) {
         var checked = (settings.itip_notify & 1 ? ' checked="checked"' : '');
 
         if (action == 'remove' && cal.group != 'shared' && !_is_organizer && _is_attendee) {
           decline = true;
           checked = event.status != 'CANCELLED' ? checked : '';
           html += '<div class="message dialog-message ui alert boxwarning">' +
             '<label><input class="confirm-attendees-decline" type="checkbox"' + checked + ' value="1" name="decline" />&nbsp;' +
             rcmail.gettext('itipdeclineevent', 'calendar') + 
             '</label></div>';
         }
         else if (_is_organizer) {
           notify = true;
           if (settings.itip_notify & 2) {
             html += '<div class="message dialog-message ui alert boxwarning">' +
               '<label><input class="confirm-attendees-donotify" type="checkbox"' + checked + ' value="1" name="notify" />&nbsp;' +
                 rcmail.gettext((action == 'remove' ? 'sendcancellation' : 'sendnotifications'), 'calendar') +
               '</label></div>';
           }
           else {
             data._notify = settings.itip_notify;
           }
         }
       }
 
       // recurring event: user needs to select the savemode
       if (event.recurrence) {
         var future_disabled = '', message_label = (action == 'remove' ? 'removerecurringeventwarning' : 'changerecurringeventwarning');
 
         // disable the 'future' savemode if I'm an attendee
         // reason: no calendaring system supports the thisandfuture range parameter in iTip REPLY
         if (action == 'remove' && !_is_organizer && _is_attendee) {
           future_disabled = ' disabled';
         }
 
         html += '<div class="message dialog-message ui alert boxwarning">' + rcmail.gettext(message_label, 'calendar') + '</div>' +
           '<div class="savemode">' +
             '<a href="#current" class="button btn btn-secondary">' + rcmail.gettext('currentevent', 'calendar') + '</a>' +
             '<a href="#future" class="button btn btn-secondary' + future_disabled + '">' + rcmail.gettext('futurevents', 'calendar') + '</a>' +
             '<a href="#all" class="button btn btn-secondary">' + rcmail.gettext('allevents', 'calendar') + '</a>' +
             (action != 'remove' ? '<a href="#new" class="button btn btn-secondary">' + rcmail.gettext('saveasnew', 'calendar') + '</a>' : '') +
           '</div>';
       }
       
       // show dialog
       if (html) {
         var $dialog = $('<div>').html(html);
       
         $dialog.find('a.button').button().filter(':not(.disabled)').click(function(e) {
           data._savemode = String(this.href).replace(/.+#/, '');
           data._notify = settings.itip_notify;
 
           // open event edit dialog when saving as new
           if (data._savemode == 'new') {
             event._savemode = 'new';
             event_edit_dialog('edit', event);
             fc.fullCalendar('refetchEvents');
           }
           else {
             if ($dialog.find('input.confirm-attendees-donotify').length)
               data._notify = $dialog.find('input.confirm-attendees-donotify').get(0).checked ? 1 : 0;
             if (decline) {
               data._decline = $dialog.find('input.confirm-attendees-decline:checked').length;
               data._notify = 0;
             }
             update_event(action, data);
           }
 
           $dialog.dialog("close");
           return false;
         });
         
         var buttons = [];
 
         if (!event.recurrence) {
           buttons.push({
             text: rcmail.gettext((action == 'remove' ? 'delete' : 'save'), 'calendar'),
             'class': action == 'remove' ? 'delete mainaction' : 'save mainaction',
             click: function() {
               data._notify = notify && $dialog.find('input.confirm-attendees-donotify:checked').length ? 1 : 0;
               data._decline = decline && $dialog.find('input.confirm-attendees-decline:checked').length ? 1 : 0;
               update_event(action, data);
               $(this).dialog("close");
             }
           });
         }
 
         buttons.push({
           text: rcmail.gettext('cancel', 'calendar'),
           'class': 'cancel',
           click: function() {
             $(this).dialog("close");
           }
         });
 
         $dialog.dialog({
           modal: true,
           width: 460,
           dialogClass: 'warning',
           title: rcmail.gettext((action == 'remove' ? 'removeeventconfirm' : 'changeeventconfirm'), 'calendar'),
           buttons: buttons,
           open: function() {
             setTimeout(function(){
               $dialog.parent().find('.ui-button:not(.ui-dialog-titlebar-close)').first().focus();
             }, 5);
           },
           close: function(){
             $dialog.dialog("destroy").remove();
             if (!rcmail.busy)
               fc.fullCalendar('refetchEvents');
           }
         }).addClass('event-update-confirm').show();
 
         return false;
       }
       // show regular confirm box when deleting
       else if (action == 'remove' && !cal.undelete) {
         if (!confirm(rcmail.gettext('deleteventconfirm', 'calendar')))
           return false;
       }
 
       // do update
       update_event(action, data);
 
       return true;
     };
 
-    var update_agenda_toolbar = function()
-    {
-//      $('#agenda-listrange').val();
-//      $('#agenda-listsections').val(fc.fullCalendar('option', 'listSections'));
-    }
-
 
     /*** public methods ***/
 
     /**
      * Remove saving lock and free the UI for new input
      */
     this.unlock_saving = function()
     {
         if (me.saving_lock)
             rcmail.set_busy(false, null, me.saving_lock);
     };
 
-    // opens calendar day-view in a popup
-    this.fisheye_view = function(date)
-    {
-      $('#fish-eye-view:ui-dialog').dialog('close');
-      
-      // create list of active event sources
-      var src, cals = {}, sources = [];
-      for (var id in this.calendars) {
-        src = $.extend({}, this.calendars[id]);
-        src.editable = false;
-        src.url = null;
-        src.events = [];
-
-        if (src.active) {
-          cals[id] = src;
-          sources.push(src);
-        }
-      }
-      
-      // copy events already loaded
-      var events = fc.fullCalendar('clientEvents');
-      for (var event, i=0; i< events.length; i++) {
-        event = events[i];
-        if (event.source && (src = cals[event.source.id])) {
-          src.events.push(event);
-        }
-      }
-      
-      var h = $(window).height() - 50;
-      var dialog = $('<div>')
-        .attr('id', 'fish-eye-view')
-        .dialog({
-          modal: true,
-          width: 680,
-          height: h,
-          title: format_date(date, 'dddd ' + settings.date_long),
-          buttons: [{
-            text: rcmail.gettext('cancel', 'calendar'),
-            'class': 'cancel',
-            click: function() { $(this).dialog("close"); }
-          }],
-          close: function(){
-            dialog.dialog("destroy");
-            me.fisheye_date = null;
-          }
-        })
-        .fullCalendar($.extend({}, fullcalendar_defaults, {
-          defaultView: 'agendaDay',
-          header: { left: '', center: '', right: '' },
-          height: h - 50,
-          defaultDate: date,
-          eventSources: sources
-        }));
-
-        this.fisheye_date = date;
-    };
-
     // opens the given calendar in a popup dialog
     this.quickview = function(id, shift)
     {
       var src, in_quickview = false;
       $.each(this.quickview_sources, function(i,cal) {
         if (cal.id == id) {
           in_quickview = true;
           src = cal;
         }
       });
 
       // remove source from quickview
       if (in_quickview && shift) {
         this.quickview_sources = $.grep(this.quickview_sources, function(src) { return src.id != id; });
       }
       else {
         if (!shift) {
           // remove all current quickview event sources
           if (this.quickview_active) {
             fc.fullCalendar('removeEventSources');
           }
 
           this.quickview_sources = [];
 
           // uncheck all active quickview icons
           calendars_list.container.find('div.focusview')
             .add('#calendars .searchresults div.focusview')
             .removeClass('focusview')
               .find('a.quickview').attr('aria-checked', 'false');
         }
 
         if (!in_quickview) {
           // clone and modify calendar properties
           src = $.extend({}, this.calendars[id]);
           src.url += '&_quickview=1';
           this.quickview_sources.push(src);
         }
       }
 
       // disable quickview
       if (this.quickview_active && !this.quickview_sources.length) {
         // register regular calendar event sources
         $.each(this.calendars, function(k, cal) {
           if (cal.active)
             fc.fullCalendar('addEventSource', cal);
         });
 
         this.quickview_active = false;
         $('body').removeClass('quickview-active');
 
         // uncheck all active quickview icons
         calendars_list.container.find('div.focusview')
           .add('#calendars .searchresults div.focusview')
           .removeClass('focusview')
             .find('a.quickview').attr('aria-checked', 'false');
       }
       // activate quickview
       else if (!this.quickview_active) {
         // remove regular calendar event sources
         fc.fullCalendar('removeEventSources');
 
         // register quickview event sources
         $.each(this.quickview_sources, function(i, src) {
           fc.fullCalendar('addEventSource', src);
         });
 
         this.quickview_active = true;
         $('body').addClass('quickview-active');
       }
       // update quickview sources
       else if (in_quickview) {
         fc.fullCalendar('removeEventSource', src);
       }
       else if (src) {
         fc.fullCalendar('addEventSource', src);
       }
 
       // activate quickview icon
       if (this.quickview_active) {
         $(calendars_list.get_item(id)).find('.calendar').first()
           .add('#calendars .searchresults .cal-' + id)
           [in_quickview ? 'removeClass' : 'addClass']('focusview')
             .find('a.quickview').attr('aria-checked', in_quickview ? 'false' : 'true');
       }
     };
 
     // disable quickview mode
     function reset_quickview()
     {
       // remove all current quickview event sources
       if (me.quickview_active) {
         fc.fullCalendar('removeEventSources');
         me.quickview_sources = [];
       }
 
       // register regular calendar event sources
       $.each(me.calendars, function(k, cal) {
         if (cal.active)
           fc.fullCalendar('addEventSource', cal);
       });
 
       // uncheck all active quickview icons
       calendars_list.container.find('div.focusview')
         .add('#calendars .searchresults div.focusview')
         .removeClass('focusview')
           .find('a.quickview').attr('aria-checked', 'false');
 
       me.quickview_active = false;
       $('body').removeClass('quickview-active');
     };
 
     //public method to show the print dialog.
     this.print_calendars = function(view)
     {
       if (!view) view = fc.fullCalendar('getView').name;
       var date = fc.fullCalendar('getDate').toDate();
-//      var sections = fc.fullCalendar('option', 'listSections');
 
       rcmail.open_window(rcmail.url('print', {
           view: view,
           date: date2unixtime(date),
           range: settings.agenda_range,
-          // sections: sections,
           search: this.search_query
         }), true, true);
     };
 
     // public method to bring up the new event dialog
     this.add_event = function(templ) {
       if (this.selected_calendar) {
         var now = new Date();
         var date = fc.fullCalendar('getDate').toDate();
         date.setHours(now.getHours()+1);
         date.setMinutes(0);
         var end = new Date(date.getTime());
         end.setHours(date.getHours()+1);
         event_edit_dialog('new', $.extend({ start:date, end:end, allDay:false, calendar:this.selected_calendar }, templ || {}));
       }
     };
 
     // delete the given event after showing a confirmation dialog
     this.delete_event = function(event) {
       // show confirm dialog for recurring events, use jquery UI dialog
       return update_event_confirm('remove', event, { id:event.id, calendar:event.calendar, attendees:event.attendees });
     };
 
     // opens a jquery UI dialog with event properties (or empty for creating a new calendar)
     this.calendar_edit_dialog = function(calendar)
     {
       if (!calendar)
         calendar = { name:'', color:'cc0000', editable:true, showalarms:true };
 
       var title = rcmail.gettext((calendar.id ? 'editcalendar' : 'createcalendar'), 'calendar'),
         params = {action: calendar.id ? 'form-edit' : 'form-new', c: {id: calendar.id}, _framed: 1},
         $dialog = $('<iframe>').attr('src', rcmail.url('calendar', params)).on('load', function() {
           var contents = $(this).contents();
           contents.find('#calendar-name')
             .prop('disabled', !calendar.editable)
             .val(calendar.editname || calendar.name)
             .select();
           contents.find('#calendar-color')
             .val(calendar.color);
           contents.find('#calendar-showalarms')
             .prop('checked', calendar.showalarms);
         }),
         save_func = function() {
           var data,
             form = $dialog.contents().find('#calendarpropform'),
             name = form.find('#calendar-name');
 
           // form is not loaded
           if (!form || !form.length)
             return false;
 
           // do some input validation
           if (!name.val() || name.val().length < 2) {
             rcmail.alert_dialog(rcmail.gettext('invalidcalendarproperties', 'calendar'), function() {
               name.select();
             });
 
             return false;
           }
 
           // post data to server
           data = form.serializeJSON();
           if (data.color)
             data.color = data.color.replace(/^#/, '');
           if (calendar.id)
             data.id = calendar.id;
 
           me.saving_lock = rcmail.set_busy(true, 'calendar.savingdata');
           rcmail.http_post('calendar', { action:(calendar.id ? 'edit' : 'new'), c:data });
           $dialog.dialog("close");
         };
 
       rcmail.simple_dialog($dialog, title, save_func, {
         width: 600,
         height: 400
       });
     };
 
     this.calendar_remove = function(calendar)
     {
       this.calendar_destroy_source(calendar.id);
       rcmail.http_post('calendar', { action:'subscribe', c:{ id:calendar.id, active:0, permanent:0, recursive:1 } });
       return true;
     };
 
     this.calendar_delete = function(calendar)
     {
       var label = calendar.children ? 'deletecalendarconfirmrecursive' : 'deletecalendarconfirm';
       rcmail.confirm_dialog(rcmail.gettext(label, 'calendar'), 'delete', function() {
         rcmail.http_post('calendar', { action:'delete', c:{ id:calendar.id } });
         return true;
       });
 
       return false;
     };
 
     this.calendar_refresh_source = function(id)
     {
       // got race-conditions fc.currentFetchID when using refetchEventSources,
       // so we remove and add the source instead
       // fc.fullCalendar('refetchEventSources', me.calendars[id]);
       // TODO: Check it again with fullcalendar >= 3.9
       fc.fullCalendar('removeEventSource', me.calendars[id]);
       fc.fullCalendar('addEventSource', me.calendars[id]);
     };
 
     this.calendar_destroy_source = function(id)
     {
       var delete_ids = [];
 
       if (this.calendars[id]) {
         // find sub-calendars
         if (this.calendars[id].children) {
           for (var child_id in this.calendars) {
             if (String(child_id).indexOf(id) == 0)
               delete_ids.push(child_id);
           }
         }
         else {
           delete_ids.push(id);
         }
       }
 
       // delete all calendars in the list
       for (var i=0; i < delete_ids.length; i++) {
         id = delete_ids[i];
         calendars_list.remove(id);
         fc.fullCalendar('removeEventSource', this.calendars[id]);
         $('#edit-calendar option[value="'+id+'"]').remove();
         delete this.calendars[id];
       }
 
       if (this.selected_calendar == id) {
         this.init_calendars(true);
       }
     };
 
     // open a dialog to upload an .ics file with events to be imported
     this.import_events = function(calendar)
     {
       // close show dialog first
       var $dialog = $("#eventsimport"),
         form = rcmail.gui_objects.importform;
 
       if ($dialog.is(':ui-dialog'))
         $dialog.dialog('close');
 
       if (calendar)
         $('#event-import-calendar').val(calendar.id);
 
       var buttons = [
         {
           text: rcmail.gettext('import', 'calendar'),
           'class' : 'mainaction import',
           click: function() {
             if (form && form.elements._data.value) {
               rcmail.async_upload_form(form, 'import_events', function(e) {
                 rcmail.set_busy(false, null, me.saving_lock);
                 $('.ui-dialog-buttonpane button', $dialog.parent()).button('enable');
 
                 // display error message if no sophisticated response from server arrived (e.g. iframe load error)
                 if (me.import_succeeded === null)
                   rcmail.display_message(rcmail.get_label('importerror', 'calendar'), 'error');
               });
 
               // display upload indicator (with extended timeout)
               var timeout = rcmail.env.request_timeout;
               rcmail.env.request_timeout = 600;
               me.import_succeeded = null;
               me.saving_lock = rcmail.set_busy(true, 'uploading');
               $('.ui-dialog-buttonpane button', $dialog.parent()).button('disable');
 
               // restore settings
               rcmail.env.request_timeout = timeout;
             }
           }
         },
         {
           text: rcmail.gettext('cancel', 'calendar'),
           'class': 'cancel',
           click: function() { $dialog.dialog("close"); }
         }
       ];
 
       // open jquery UI dialog
       $dialog.dialog({
         modal: true,
         resizable: false,
         closeOnEscape: false,
         title: rcmail.gettext('importevents', 'calendar'),
         close: function() {
           $('.ui-dialog-buttonpane button', $dialog.parent()).button('enable');
           $dialog.dialog("destroy").hide();
         },
         buttons: buttons,
         width: 520
       }).show();
     };
 
     // callback from server if import succeeded
     this.import_success = function(p)
     {
       this.import_succeeded = true;
       $("#eventsimport:ui-dialog").dialog('close');
       rcmail.set_busy(false, null, me.saving_lock);
       rcmail.gui_objects.importform.reset();
 
       if (p.refetch)
         this.refresh(p);
     };
 
     // callback from server to report errors on import
     this.import_error = function(p)
     {
       this.import_succeeded = false;
       rcmail.set_busy(false, null, me.saving_lock);
       rcmail.display_message(p.message || rcmail.get_label('importerror', 'calendar'), 'error');
     }
 
     // open a dialog to select calendars for export
     this.export_events = function(calendar)
     {
       // close show dialog first
       var $dialog = $("#eventsexport"),
         form = rcmail.gui_objects.exportform;
 
       if ($dialog.is(':ui-dialog'))
         $dialog.dialog('close');
 
       if (calendar)
         $('#event-export-calendar').val(calendar.id);
 
       $('#event-export-range').change(function(e){
         var custom = $('option:selected', this).val() == 'custom',
           input = $('#event-export-startdate')
         input.parent()[(custom?'show':'hide')]();
         if (custom)
           input.select();
       })
 
       var buttons = [
         {
           text: rcmail.gettext('export', 'calendar'),
           'class': 'mainaction export',
           click: function() {
             if (form) {
               var start = 0, range = $('#event-export-range option:selected', this).val(),
                 source = $('#event-export-calendar option:selected').val(),
                 attachmt = $('#event-export-attachments').get(0).checked;
 
               if (range == 'custom')
                 start = date2unixtime(me.parse_datetime('00:00', $('#event-export-startdate').val()));
               else if (range > 0)
                 start = 'today -' + range + ' months';
 
               rcmail.goto_url('export_events', { source:source, start:start, attachments:attachmt?1:0 }, false);
             }
             $dialog.dialog("close");
           }
         },
         {
           text: rcmail.gettext('cancel', 'calendar'),
           'class': 'cancel',
           click: function() { $dialog.dialog("close"); }
         }
       ];
 
       // open jquery UI dialog
       $dialog.dialog({
         modal: true,
         resizable: false,
         closeOnEscape: false,
         title: rcmail.gettext('exporttitle', 'calendar'),
         close: function() {
           $('.ui-dialog-buttonpane button', $dialog.parent()).button('enable');
           $dialog.dialog("destroy").hide();
         },
         buttons: buttons,
         width: 520
       }).show();
     };
 
     // download the selected event as iCal
     this.event_download = function(event)
     {
       if (event && event.id) {
         rcmail.goto_url('export_events', { source:event.calendar, id:event.id, attachments:1 }, false);
       }
     };
 
     // open the message compose step with a calendar_event parameter referencing the selected event.
     // the server-side plugin hook will pick that up and attach the event to the message.
     this.event_sendbymail = function(event, e)
     {
       if (event && event.id) {
         rcmail.command('compose', { _calendar_event:event._id }, e ? e.target : null, e);
       }
     };
 
     // display the edit dialog, request 'new' action and pass the selected event
     this.event_copy = function(event) {
       if (event && event.id) {
         var copy = $.extend(true, {}, event);
 
         delete copy.id;
         delete copy._id;
         delete copy.created;
         delete copy.changed;
         delete copy.recurrence_id;
         delete copy.attachments; // @TODO
 
         $.each(copy.attendees, function (k, v) {
           if (v.role != 'ORGANIZER') {
             v.status = 'NEEDS-ACTION';
           }
         })
 
         event_edit_dialog('new', copy);
       }
     };
 
     // show URL of the given calendar in a dialog box
     this.showurl = function(calendar)
     {
       if (calendar.feedurl) {
         var dialog = $('#calendarurlbox').clone(true).removeClass('uidialog');
 
         if (calendar.caldavurl) {
           $('#caldavurl', dialog).val(calendar.caldavurl);
           $('#calendarcaldavurl', dialog).show();
         }
         else {
           $('#calendarcaldavurl', dialog).hide();
         }
 
         rcmail.simple_dialog(dialog, rcmail.gettext('showurl', 'calendar'), null, {
           open: function() { $('#calfeedurl', dialog).val(calendar.feedurl).select(); },
           cancel_button: 'close'
         });
       }
     };
 
     // show free-busy URL in a dialog box
     this.showfburl = function()
     {
       var dialog = $('#fburlbox').clone(true);
 
       rcmail.simple_dialog(dialog, rcmail.gettext('showfburl', 'calendar'), null, {
         open: function() { $('#fburl', dialog).val(settings.freebusy_url).select(); },
         cancel_button: 'close'
       });
     };
 
     // refresh the calendar view after saving event data
     this.refresh = function(p)
     {
       var source = me.calendars[p.source];
 
       // helper function to update the given fullcalendar view
       function update_view(view, event, source) {
         var existing = view.fullCalendar('clientEvents', event._id);
         if (existing.length) {
           $.extend(existing[0], event);
           view.fullCalendar('updateEvent', existing[0]);
           // remove old recurrence instances
           if (event.recurrence && !event.recurrence_id)
             view.fullCalendar('removeEvents', function(e){ return e._id.indexOf(event._id+'-') == 0; });
         }
         else {
           event.source = view.fullCalendar('getEventSourceById', source.id);  // link with source
           view.fullCalendar('renderEvent', event);
         }
       }
 
       // remove temp events
       fc.fullCalendar('removeEvents', function(e){ return e.temp; });
 
       if (source && (p.refetch || (p.update && !source.active))) {
         // activate event source if new event was added to an invisible calendar
         if (this.quickview_active) {
           // map source to the quickview_sources equivalent
           $.each(this.quickview_sources, function(src) {
             if (src.id == source.id) {
               source = src;
               return false;
             }
           });
         }
         else if (!source.active) {
           source.active = true;
           $('#rcmlical' + source.id + ' input').prop('checked', true);
         }
 
         fc.fullCalendar('refetchEventSources', source.id);
         fetch_counts();
       }
       // add/update single event object
       else if (source && p.update) {
         var event = p.update;
         event.temp = false;
         event.editable = 0;
 
-          // update fish-eye view
-        if (this.fisheye_date)
-          update_view($('#fish-eye-view'), event, source);
-
         // update main view
         event.editable = source.editable;
         update_view(fc, event, source);
 
         // update the currently displayed event dialog
         if ($('#eventshow').is(':visible') && me.selected_event && me.selected_event.id == event.id)
           event_show_dialog(event)
       }
       // refetch all calendars
       else if (p.refetch) {
         fc.fullCalendar('refetchEvents');
         fetch_counts();
       }
     };
 
     // modify query parameters for refresh requests
     this.before_refresh = function(query)
     {
       var view = fc.fullCalendar('getView');
 
       query.start = date2unixtime(view.start.toDate());
       query.end = date2unixtime(view.end.toDate());
 
       if (this.search_query)
         query.q = this.search_query;
 
       return query;
     };
 
     // callback from server providing event counts
     this.update_counts = function(p)
     {
       $.each(p.counts, function(cal, count) {
         var li = calendars_list.get_item(cal),
           bubble = $(li).children('.calendar').find('span.count');
 
         if (!bubble.length && count > 0) {
           bubble = $('<span>')
             .addClass('count')
             .appendTo($(li).children('.calendar').first())
         }
 
         if (count > 0) {
           bubble.text(count).show();
         }
         else {
           bubble.text('').hide();
         }
       });
     };
 
     // callback after an iTip message event was imported
     this.itip_message_processed = function(data)
     {
       // remove temporary iTip source
       fc.fullCalendar('removeEventSource', this.calendars['--invitation--itip']);
 
       $('#eventshow:ui-dialog').dialog('close');
       this.selected_event = null;
 
       // refresh destination calendar source
       this.refresh({ source:data.calendar, refetch:true });
 
       this.unlock_saving();
 
       // process 'after_action' in mail task
       if (window.opener && window.opener.rcube_libcalendaring)
         window.opener.rcube_libcalendaring.itip_message_processed(data);
     };
 
     // reload the calendar view by keeping the current date/view selection
     this.reload_view = function()
     {
       var query = { view: fc.fullCalendar('getView').name },
         date = fc.fullCalendar('getDate');
       if (date)
         query.date = date2unixtime(date.toDate());
       rcmail.redirect(rcmail.url('', query));
     }
 
     // update browser location to remember current view
     this.update_state = function()
     {
       var query = { view: current_view },
         date = fc.fullCalendar('getDate');
       if (date)
         query.date = date2unixtime(date.toDate());
 
       if (window.history.replaceState)
         window.history.replaceState({}, document.title, rcmail.url('', query).replace('&_action=', ''));
     };
 
     this.resource_search = resource_search;
     this.reset_resource_search = reset_resource_search;
     this.add_resource2event = add_resource2event;
     this.resource_data_load = resource_data_load;
     this.resource_owner_load = resource_owner_load;
 
 
     /***  event searching  ***/
 
     // execute search
     this.quicksearch = function()
     {
       if (rcmail.gui_objects.qsearchbox) {
         var q = rcmail.gui_objects.qsearchbox.value;
         if (q != '') {
           var id = 'search-'+q;
           var sources = [];
           
           if (me.quickview_active)
             reset_quickview();
           
           if (this._search_message)
             rcmail.hide_message(this._search_message);
           
           $.each(fc.fullCalendar('getEventSources'), function() {
             this.url = this.url.replace(/&q=.+/, '') + '&q=' + urlencode(q);
             me.calendars[this.id].url = this.url;
             sources.push(this.id);
           });
           id += '@'+sources.join(',');
           
           // ignore if query didn't change
           if (this.search_request == id) {
             return;
           }
           // remember current view
           else if (!this.search_request) {
             this.default_view = fc.fullCalendar('getView').name;
           }
           
           this.search_request = id;
           this.search_query = q;
           
           // change to list view
-          // fc.fullCalendar('option', 'listSections', 'month');
           fc.fullCalendar('changeView', 'list');
-          
-          update_agenda_toolbar();
-          
+
           // refetch events with new url (if not already triggered by changeView)
           if (!this.is_loading)
             fc.fullCalendar('refetchEvents');
         }
         else  // empty search input equals reset
           this.reset_quicksearch();
       }
     };
 
     // reset search and get back to normal event listing
     this.reset_quicksearch = function()
     {
       $(rcmail.gui_objects.qsearchbox).val('');
 
       if (this._search_message)
         rcmail.hide_message(this._search_message);
 
       if (this.search_request) {
         $.each(fc.fullCalendar('getEventSources'), function() {
           this.url = this.url.replace(/&q=.+/, '');
           me.calendars[this.id].url = this.url;
         });
 
         this.search_request = this.search_query = null;
 
         fc.fullCalendar('refetchEvents');
       }
     };
 
     // callback if all sources have been fetched from server
     this.events_loaded = function()
     {
       if (this.search_request && !fc.fullCalendar('clientEvents').length) {
         this._search_message = rcmail.display_message(rcmail.gettext('searchnoresults', 'calendar'), 'notice');
       }
-
-      if (this.fisheye_date)
-        this.fisheye_view(this.fisheye_date);
     };
 
     // adjust calendar view size
     this.view_resize = function()
     {
       var footer = fc.fullCalendar('getView').name == 'list' ? $('#agendaoptions').outerHeight() : 0;
       fc.fullCalendar('option', 'height', $('#calendar').height() - footer);
     };
 
     // mark the given calendar folder as selected
     this.select_calendar = function(id, nolistupdate)
     {
       if (!nolistupdate)
         calendars_list.select(id);
 
       // trigger event hook
       rcmail.triggerEvent('selectfolder', { folder:id, prefix:'rcmlical' });
 
       this.selected_calendar = id;
 
       rcmail.update_state({source: id});
       rcmail.enable_command('addevent', this.calendars[id] && this.calendars[id].editable);
     };
 
     // register the given calendar to the current view
     var add_calendar_source = function(cal)
     {
       var color, brightness, select, id = cal.id;
 
       me.calendars[id] = $.extend({
         url: rcmail.url('calendar/load_events', { source: id }),
         className: ['fc-event-cal-' + id],
         id: id
       }, cal);
 
       // choose black text color when background is bright, white otherwise
       if (color = settings.event_coloring % 2  ? '' : '#' + cal.color) {
         me.calendars[id].color = color;
         me.calendars[id].textColor = 'white';
 
         if (/^#([a-f0-9]{2})([a-f0-9]{2})([a-f0-9]{2})$/i.test(color)) {
           // use information about brightness calculation found at
           // http://javascriptrules.com/2009/08/05/css-color-brightness-contrast-using-javascript/
           brightness = (parseInt(RegExp.$1, 16) * 299 + parseInt(RegExp.$2, 16) * 587 + parseInt(RegExp.$3, 16) * 114) / 1000;
           if (brightness > 125)
             me.calendars[id].textColor = '#222';
         }
       }
 
       if (fc && (cal.active || cal.subscribed)) {
         if (cal.active)
           fc.fullCalendar('addEventSource', me.calendars[id]);
 
         var submit = { id: id, active: cal.active ? 1 : 0 };
         if (cal.subscribed !== undefined)
             submit.permanent = cal.subscribed ? 1 : 0;
         rcmail.http_post('calendar', { action:'subscribe', c:submit });
       }
 
       // insert to #calendar-select options if writeable
       select = $('#edit-calendar');
       if (fc && me.has_permission(cal, 'i') && select.length && !select.find('option[value="'+id+'"]').length) {
         $('<option>').attr('value', id).html(cal.name).appendTo(select);
       }
     }
 
     // fetch counts for some calendars from the server
     var fetch_counts = function()
     {
       if (count_sources.length) {
         setTimeout(function() {
           rcmail.http_request('calendar/count', { source:count_sources });
         }, 500);
       }
     };
 
     this.init_calendars = function(refresh)
     {
       var id, cal, active;
 
       for (id in rcmail.env.calendars) {
         cal = rcmail.env.calendars[id];
         active = cal.active || false;
 
         if (!refresh) {
           add_calendar_source(cal);
 
           // check active calendars
           $('#rcmlical'+id+' > .calendar input').prop('checked', active);
 
           if (active) {
             event_sources.push(this.calendars[id]);
           }
           if (cal.counts) {
             count_sources.push(id);
           }
         }
 
         if (cal.editable && (!this.selected_calendar || refresh)) {
           this.selected_calendar = id;
           if (refresh) {
             this.select_calendar(id);
             refresh = false;
           }
         }
       }
     };
 
 
     /***  startup code  ***/
 
     // initialize treelist widget that controls the calendars list
     var widget_class = window.kolab_folderlist || rcube_treelist_widget;
     calendars_list = new widget_class(rcmail.gui_objects.calendarslist, {
       id_prefix: 'rcmlical',
       selectable: true,
       save_state: true,
       keyboard: false,
       searchbox: '#calendarlistsearch',
       search_action: 'calendar/calendar',
       search_sources: [ 'folders', 'users' ],
       search_title: rcmail.gettext('calsearchresults','calendar')
     });
     calendars_list.addEventListener('select', function(node) {
       if (node && node.id && me.calendars[node.id]) {
         me.select_calendar(node.id, true);
         rcmail.enable_command('calendar-edit', 'calendar-showurl', 'calendar-showfburl', true);
         rcmail.enable_command('calendar-delete', me.calendars[node.id].editable);
         rcmail.enable_command('calendar-remove', me.calendars[node.id] && me.calendars[node.id].removable);
       }
     });
     calendars_list.addEventListener('insert-item', function(p) {
       var cal = p.data;
       if (cal && cal.id) {
         add_calendar_source(cal);
 
         // add css classes related to this calendar to document
         if (cal.css) {
           $('<style type="text/css"></style>')
             .html(cal.css)
             .appendTo('head');
         }
       }
     });
     calendars_list.addEventListener('subscribe', function(p) {
       var cal;
       if ((cal = me.calendars[p.id])) {
         cal.subscribed = p.subscribed || false;
         rcmail.http_post('calendar', { action:'subscribe', c:{ id:p.id, active:cal.active?1:0, permanent:cal.subscribed?1:0 } });
       }
     });
     calendars_list.addEventListener('remove', function(p) {
       if (me.calendars[p.id] && me.calendars[p.id].removable) {
         me.calendar_remove(me.calendars[p.id]);
       }
     });
     calendars_list.addEventListener('search-complete', function(data) {
       if (data.length)
         rcmail.display_message(rcmail.gettext('nrcalendarsfound','calendar').replace('$nr', data.length), 'voice');
       else
         rcmail.display_message(rcmail.gettext('nocalendarsfound','calendar'), 'notice');
     });
     calendars_list.addEventListener('click-item', function(event) {
       // handle clicks on quickview icon: temprarily add this source and open in quickview
       if ($(event.target).hasClass('quickview') && event.data) {
         if (!me.calendars[event.data.id]) {
           event.data.readonly = true;
           event.data.active = false;
           event.data.subscribed = false;
           add_calendar_source(event.data);
         }
         me.quickview(event.data.id, event.shiftKey || event.metaKey || event.ctrlKey);
         return false;
       }
     });
 
     // init (delegate) event handler on calendar list checkboxes
     $(rcmail.gui_objects.calendarslist).on('click', 'input[type=checkbox]', function(e) {
       e.stopPropagation();
 
       if (me.quickview_active) {
         this.checked = !this.checked;
         return false;
       }
 
       var id = this.value;
       if (me.calendars[id]) {  // add or remove event source on click
         var action;
         if (this.checked) {
           action = 'addEventSource';
           me.calendars[id].active = true;
         }
         else {
           action = 'removeEventSource';
           me.calendars[id].active = false;
         }
 
         // adjust checked state of original list item
         if (calendars_list.is_search()) {
           calendars_list.container.find('input[value="'+id+'"]').prop('checked', this.checked);
         }
 
         // add/remove event source
         fc.fullCalendar(action, me.calendars[id]);
         rcmail.http_post('calendar', { action:'subscribe', c:{ id:id, active:me.calendars[id].active?1:0 } });
       }
     })
     .on('keypress', 'input[type=checkbox]', function(e) {
         // select calendar on <Enter>
         if (e.keyCode == 13) {
             calendars_list.select(this.value);
             return rcube_event.cancel(e);
         }
     })
     // init (delegate) event handler on quickview links
     .on('click', 'a.quickview', function(e) {
       var id = $(this).closest('li').attr('id').replace(/^rcmlical/, '');
 
       if (calendars_list.is_search())
         id = id.replace(/--xsR$/, '');
 
       if (me.calendars[id])
         me.quickview(id, e.shiftKey || e.metaKey || e.ctrlKey);
 
       if (!rcube_event.is_keyboard(e) && this.blur)
         this.blur();
 
       e.stopPropagation();
       return false;
     });
 
     // register dbl-click handler to open calendar edit dialog
     $(rcmail.gui_objects.calendarslist).on('dblclick', ':not(.virtual) > .calname', function(e){
       var id = $(this).closest('li').attr('id').replace(/^rcmlical/, '');
       me.calendar_edit_dialog(me.calendars[id]);
     });
 
     // Make Elastic checkboxes pretty
     if (window.UI && UI.pretty_checkbox) {
       $(rcmail.gui_objects.calendarslist).find('input[type=checkbox]').each(function() {
         UI.pretty_checkbox($(this).addClass('flex-checkbox'));
       });
       calendars_list.addEventListener('add-item', function(prop) {
         UI.pretty_checkbox($(prop.li).find('input').addClass('flex-checkbox'));
       });
     }
 
     // create list of event sources AKA calendars
     this.init_calendars();
 
     // select default calendar
     if (rcmail.env.source && this.calendars[rcmail.env.source])
       this.selected_calendar = rcmail.env.source;
     else if (settings.default_calendar && this.calendars[settings.default_calendar] && this.calendars[settings.default_calendar].editable)
       this.selected_calendar = settings.default_calendar;
 
     if (this.selected_calendar)
       this.select_calendar(this.selected_calendar);
 
     var viewdate = new Date();
     if (rcmail.env.date)
       viewdate.setTime(fromunixtime(rcmail.env.date));
 
     // add source with iTip event data for rendering
     if (rcmail.env.itip_events && rcmail.env.itip_events.length) {
       me.calendars['--invitation--itip'] = {
         events: rcmail.env.itip_events,
         className: ['fc-event-cal---invitation--itip'],
         color: '#fff',
         textColor: '#333',
         editable: false,
         rights: 'lrs',
         attendees: true
       };
       event_sources.push(me.calendars['--invitation--itip']);
     }
 
     // initalize the fullCalendar plugin
     var fc = $('#calendar').fullCalendar($.extend({}, fullcalendar_defaults, {
       header: {
         right: 'prev,next today',
         center: 'title',
         left: 'agendaDay,agendaWeek,month,list'
       },
       defaultDate: viewdate,
       height: $('#calendar').height(),
       eventSources: event_sources,
       selectable: true,
       selectHelper: false,
       loading: function(isLoading) {
         me.is_loading = isLoading;
         this._rc_loading = rcmail.set_busy(isLoading, me.search_request ? 'searching' : 'loading', this._rc_loading);
         // trigger callback (using timeout, otherwise clientEvents is always empty)
         if (!isLoading)
           setTimeout(function() { me.events_loaded(); }, 20);
       },
       // callback for date range selection
       select: function(start, end, e, view) {
         var range_select = (start.hasTime() || start != end)
         if (dialog_check(e) && range_select)
           event_edit_dialog('new', { start:start, end:end, allDay:!start.hasTime(), calendar:me.selected_calendar });
         if (range_select || ignore_click)
           view.calendar.unselect();
       },
       // callback for clicks in all-day box
       dayClick: function(date, e, view) {
         var now = new Date().getTime();
         if (now - day_clicked_ts < 400 && day_clicked == date.toDate().getTime()) {  // emulate double-click on day
           var enddate = new Date();
           if (date.hasTime())
             enddate.setTime(date.toDate().getTime() + DAY_MS - 60000);
           return event_edit_dialog('new', { start:date, end:enddate, allDay:!date.hasTime(), calendar:me.selected_calendar });
         }
 
         if (!ignore_click) {
           view.calendar.gotoDate(date);
           if (day_clicked && new Date(day_clicked).getMonth() != date.toDate().getMonth())
             view.calendar.select(date, date);
         }
         day_clicked = date.toDate().getTime();
         day_clicked_ts = now;
       },
       // callback when an event was dragged and finally dropped
       eventDrop: function(event, delta, revertFunc) {
         if (!event.end || event.end.diff(event.start) < 0) {
           if (event.allDay)
             event.end = moment(event.start).hour(13).minute(0).second(0);
           else
             event.end = moment(event.start).add(2, 'hours');
         }
         else if (event.allDay) {
           event.end.subtract(1, 'days').hour(13);
         }
 
         if (event.allDay)
           event.start.hour(12);
 
         // send move request to server
         var data = {
           id: event.id,
           calendar: event.calendar,
           start: date2servertime(event.start),
           end: date2servertime(event.end),
           allDay: event.allDay?1:0
         };
 
         update_event_confirm('move', event, data);
       },
       // callback for event resizing
       eventResize: function(event, delta) {
         // sanitize event dates
         if (event.allDay) {
           event.start.hours(12);
           event.end.hour(13).subtract(1, 'days');
         }
 
         // send resize request to server
         var data = {
           id: event.id,
           calendar: event.calendar,
           start: date2servertime(event.start),
           end: date2servertime(event.end),
           allDay: event.allDay?1:0
         };
 
         update_event_confirm('resize', event, data);
       },
       viewRender: function(view, element) {
         $('#agendaoptions')[view.name == 'list' ? 'show' : 'hide']();
         if (minical) {
           window.setTimeout(function(){ minical.datepicker('setDate', fc.fullCalendar('getDate').toDate()); }, exec_deferred);
           if (view.name != current_view)
             me.view_resize();
           current_view = view.name;
           me.update_state();
         }
 
         if (view.name == 'list') {
           var viewStart = moment(view.start);
 
           $('#calendar .fc-prev-button').off('click').on('click', function() {
             fc.fullCalendar('gotoDate', viewStart.subtract(settings.agenda_range, 'days'));
           });
           $('#calendar .fc-next-button').off('click').on('click', function() {
             fc.fullCalendar('gotoDate', viewStart.add(settings.agenda_range, 'days'));
           });
         }
       },
       eventAfterAllRender: function(view) {
         if (view.name == 'list') {
           // Fix colspan of headers after we added Location column
           fc.find('tr.fc-list-heading > td').attr('colspan', 4);
         }
       }
     }));
 
     // if start date is changed, shift end date according to initial duration
     var shift_enddate = function(dateText) {
       var newstart = me.parse_datetime('0', dateText);
       var newend = new Date(newstart.getTime() + $('#edit-startdate').data('duration') * 1000);
       $('#edit-enddate').val(format_date(newend, me.settings.date_format));
       event_times_changed();
     };
 
     // Set as calculateWeek to determine the week of the year based on the ISO 8601 definition.
     // Uses the default $.datepicker.iso8601Week() function but takes firstDay setting into account.
     // This is a temporary fix until http://bugs.jqueryui.com/ticket/8420 is resolved.
     var iso8601Week = me.datepicker_settings.calculateWeek = function(date) {
       var mondayOffset = Math.abs(1 - me.datepicker_settings.firstDay);
       return $.datepicker.iso8601Week(new Date(date.getTime() + mondayOffset * 86400000));
     };
 
     var minical;
     var init_calendar_ui = function()
     {
       var pretty_select = function(elem) {
         // for Elastic
         if (window.UI && UI.pretty_select) {
           $(elem).addClass('form-control custom-select').each(function() { UI.pretty_select(this); });
         }
       };
 
       // initialize small calendar widget using jQuery UI datepicker
       minical = $('#datepicker').datepicker($.extend(me.datepicker_settings, {
         inline: true,
         changeMonth: true,
         changeYear: true,
         onSelect: function(dateText, inst) {
           ignore_click = true;
           var d = minical.datepicker('getDate');
           fc.fullCalendar('gotoDate', d)
           fc.fullCalendar('select', d, d);
           setTimeout(function() { pretty_select($('select', minical)); }, 25);
         },
         onChangeMonthYear: function(year, month, inst) {
           minical.data('year', year).data('month', month);
           setTimeout(function() { pretty_select($('select', minical)); }, 25);
         },
         beforeShowDay: function(date) {
           // TODO: this pretty_select() calls should be implemented in a different way
           setTimeout(function() { pretty_select($('select', minical)); }, 25);
 
           var view = fc.fullCalendar('getView'),
             dt = moment(date).format('YYYYMMDD'),
             active = view.start && view.start.format('YYYYMMDD') <= dt && view.end.format('YYYYMMDD') > dt;
 
           return [ true, (active ? 'ui-datepicker-activerange ui-datepicker-active-' + view.name : ''), ''];
         }
       })) // set event handler for clicks on calendar week cell of the datepicker widget
         .on('click', 'td.ui-datepicker-week-col', function(e) {
           var cell = $(e.target);
           if (e.target.tagName == 'TD') {
             var base_date = minical.datepicker('getDate');
             if (minical.data('month'))
               base_date.setMonth(minical.data('month')-1);
             if (minical.data('year'))
               base_date.setYear(minical.data('year'));
             base_date.setHours(12);
             base_date.setDate(base_date.getDate() - ((base_date.getDay() + 6) % 7) + me.datepicker_settings.firstDay);
             var base_kw = iso8601Week(base_date),
               target_kw = parseInt(cell.html()),
               wdiff = target_kw - base_kw;
             if (wdiff > 10)  // year jump
               base_date.setYear(base_date.getFullYear() - 1);
             else if (wdiff < -10)
               base_date.setYear(base_date.getFullYear() + 1);
             // select monday of the chosen calendar week
             var day_off = base_date.getDay() - me.datepicker_settings.firstDay,
               date = new Date(base_date.getTime() - day_off * DAY_MS + wdiff * 7 * DAY_MS);
-            fc.fullCalendar('gotoDate', date)
-            fc.fullCalendar('changeView', 'agendaWeek');
+
+            fc.fullCalendar('changeView', 'agendaWeek', date);
             minical.datepicker('setDate', date);
             setTimeout(function() { pretty_select($('select', minical)); }, 25);
           }
         });
 
       minical.find('.ui-datepicker-inline').attr('aria-labelledby', 'aria-label-minical');
 
       if (rcmail.env.date) {
         var viewdate = new Date();
         viewdate.setTime(fromunixtime(rcmail.env.date));
         minical.datepicker('setDate', viewdate);
       }
 
       // init event dialog
       var tab_change = function(event, ui) {
           // newPanel.selector for jQuery-UI 1.10, newPanel.attr('id') for jQuery-UI 1.12, href for Bootstrap tabs
           var tab = (ui ? String(ui.newPanel.selector || ui.newPanel.attr('id')) : $(event.target).attr('href'))
             .replace(/^#?event-panel-/, '').replace(/s$/, '');
           var has_real_attendee = function(attendees) {
               for (var i=0; i < (attendees ? attendees.length : 0); i++) {
                 if (attendees[i].cutype != 'RESOURCE')
                   return true;
               }
             };
 
           if (tab == 'attendee' || tab == 'resource') {
             if (!rcube_event.is_keyboard(event))
               $('#edit-'+tab+'-name').select();
             // update free-busy status if needed
             if (freebusy_ui.needsupdate && me.selected_event)
               update_freebusy_status(me.selected_event);
             // add current user as organizer if non added yet
             if (tab == 'attendee' && !has_real_attendee(event_attendees)) {
               add_attendee($.extend({ role:'ORGANIZER' }, settings.identity));
               $('#edit-attendees-form .attendees-invitebox').show();
             }
           }
 
           // reset autocompletion on tab change (#3389)
           rcmail.ksearch_blur();
 
           // display recurrence warning in recurrence tab only
           if (tab == 'recurrence')
             $('#edit-recurrence-frequency').change();
           else
             $('#edit-recurrence-syncstart').hide();
       };
 
       $('#eventedit:not([data-notabs])').tabs({activate: tab_change});  // Larry
       $('#eventedit a.nav-link').on('show.bs.tab', tab_change);         // Elastic
 
       $('#edit-enddate').datepicker(me.datepicker_settings);
       $('#edit-startdate').datepicker(me.datepicker_settings).datepicker('option', 'onSelect', shift_enddate).change(function(){ shift_enddate(this.value); });
       $('#edit-enddate').datepicker('option', 'onSelect', event_times_changed).change(event_times_changed);
       $('#edit-allday').click(function(){ $('#edit-starttime, #edit-endtime')[(this.checked?'hide':'show')](); event_times_changed(); });
 
       // configure drop-down menu on time input fields based on jquery UI autocomplete
       $('#edit-starttime, #edit-endtime').each(function() {
         me.init_time_autocomplete(this, {
           container: '#eventedit',
           change: event_times_changed
         });
       });
 
       // adjust end time when changing start
       $('#edit-starttime').change(function(e) {
         var dstart = $('#edit-startdate'),
           newstart = me.parse_datetime(this.value, dstart.val()),
           newend = new Date(newstart.getTime() + dstart.data('duration') * 1000);
         $('#edit-endtime').val(format_date(newend, me.settings.time_format));
         $('#edit-enddate').val(format_date(newend, me.settings.date_format));
         event_times_changed();
       });
 
       // register events on alarms and recurrence fields
       me.init_alarms_edit('#edit-alarms');
       me.init_recurrence_edit('#eventedit');
 
       // reload free-busy status when changing the organizer identity
       $('#eventedit').on('change', '#edit-identities-list', function(e) {
         var email = settings.identities[$(this).val()],
           icon = $(this).closest('tr').find('.availability > *');
 
         if (email && icon.length) {
           icon.attr('data-email', email);
           check_freebusy_status(icon, email, me.selected_event);
         }
       });
 
       $('#event-export-startdate').datepicker(me.datepicker_settings);
 
       // init attendees autocompletion
       var ac_props;
       // parallel autocompletion
       if (rcmail.env.autocomplete_threads > 0) {
         ac_props = {
           threads: rcmail.env.autocomplete_threads,
           sources: rcmail.env.autocomplete_sources
         };
       }
       rcmail.init_address_input_events($('#edit-attendee-name'), ac_props);
       rcmail.addEventListener('autocomplete_insert', function(e) {
         var cutype, success = false;
         if (e.field.name == 'participant') {
           cutype = e.data && e.data.type == 'group' && e.result_type == 'person' ? 'GROUP' : 'INDIVIDUAL';
           success = add_attendees(e.insert, { role:'REQ-PARTICIPANT', status:'NEEDS-ACTION', cutype:cutype });
         }
         else if (e.field.name == 'resource' && e.data && e.data.email) {
           success = add_attendee($.extend(e.data, { role:'REQ-PARTICIPANT', status:'NEEDS-ACTION', cutype:'RESOURCE' }));
         }
         if (e.field && success) {
           e.field.value = '';
         }
       });
 
       $('#edit-attendee-add').click(function(){
         var input = $('#edit-attendee-name');
         rcmail.ksearch_blur();
         if (add_attendees(input.val(), { role:'REQ-PARTICIPANT', status:'NEEDS-ACTION', cutype:'INDIVIDUAL' })) {
           input.val('');
         }
       });
 
       rcmail.init_address_input_events($('#edit-resource-name'), { action:'calendar/resources-autocomplete' });
 
       $('#edit-resource-add').click(function(){
         var input = $('#edit-resource-name');
         rcmail.ksearch_blur();
         if (add_attendees(input.val(), { role:'REQ-PARTICIPANT', status:'NEEDS-ACTION', cutype:'RESOURCE' })) {
           input.val('');
         }
       });
 
       $('#edit-resource-find').click(function(){
         event_resources_dialog();
         return false;
       });
 
       $('#resource-content a.nav-link').on('click', function() {
         e.preventDefault();
         $(this).tab('show');
       });
 
       // handle change of "send invitations" checkbox
       $('#edit-attendees-invite').change(function() {
         $('#edit-attendees-donotify,input.edit-attendee-reply').prop('checked', this.checked);
         // hide/show comment field
         $('#eventedit .attendees-commentbox')[this.checked ? 'show' : 'hide']();
       });
 
       // delegate change event to "send invitations" checkbox
       $('#edit-attendees-donotify').change(function() {
         $('#edit-attendees-invite').click();
         return false;
       });
 
       $('#edit-attendee-schedule').click(function(){
         event_freebusy_dialog();
       });
 
       $('#schedule-freebusy-prev').html('&#9668;').button().click(function(){ render_freebusy_grid(-1); });
       $('#schedule-freebusy-next').html('&#9658;').button().click(function(){ render_freebusy_grid(1); }); // FIXME .parent().buttonset();
 
       $('#schedule-find-prev').button().click(function(){ freebusy_find_slot(-1); });
       $('#schedule-find-next').button().click(function(){ freebusy_find_slot(1); });
 
       $('#schedule-freebusy-workinghours').click(function(){
         freebusy_ui.workinhoursonly = this.checked;
         $('#workinghourscss').remove();
         if (this.checked)
           $('<style type="text/css" id="workinghourscss"> td.offhours { opacity:0.3; filter:alpha(opacity=30) } </style>').appendTo('head');
       });
 
       $('#event-rsvp input.button').click(function(e) {
         event_rsvp(this)
       });
 
       $('#eventedit input.edit-recurring-savemode').change(function(e) {
         var sel = $('input.edit-recurring-savemode:checked').val(),
           disabled = sel == 'current' || sel == 'future';
         $('#event-panel-recurrence input, #event-panel-recurrence select, #event-panel-attachments input').prop('disabled', disabled);
         $('#event-panel-recurrence, #event-panel-attachments')[(disabled?'addClass':'removeClass')]('disabled');
       })
 
       $('#eventshow .changersvp').click(function(e) {
         var d = $('#eventshow'),
           record = $(this).closest('.event-line,.form-group'),
           h = d.height() - record.height();
 
         record.toggle();
         $('#event-rsvp').slideDown(300, function() {
           me.dialog_resize(d.get(0), h + $(this).outerHeight());
           if (this.scrollIntoView)
             this.scrollIntoView(false);
         });
         return false;
       })
 
       // register click handler for message links
       $('#edit-event-links, #event-links').on('click', 'li a.messagelink', function(e) {
         rcmail.open_window(this.href);
         if (!rcube_event.is_keyboard(e) && this.blur)
           this.blur();
         return false;
       });
 
       // register click handler for message delete buttons
       $('#edit-event-links').on('click', 'li a.delete', function(e) {
           remove_link(e.target);
           return false;
       });
 
       $('#agenda-listrange').change(function(e){
         settings.agenda_range = parseInt($(this).val());
         fc.fullCalendar('changeView', 'list');
         // TODO: save new settings in prefs
       }).val(settings.agenda_range);
-/*
-      $('#agenda-listsections').change(function(e){
-        settings.agenda_sections = $(this).val();
-        fc.fullCalendar('option', 'listSections', settings.agenda_sections);
-        fc.fullCalendar('changeView', 'list');
-        // TODO: save new settings in prefs
-      }).val(fc.fullCalendar('option', 'listSections'));
-*/
+
       // hide event dialog when clicking somewhere into document
       $(document).bind('mousedown', dialog_check);
 
       rcmail.set_busy(false, 'loading', ui_loading);
     }
 
     // initialize more UI elements (deferred)
     window.setTimeout(init_calendar_ui, exec_deferred);
 
     // fetch counts for some calendars
     fetch_counts();
 
     // Save-as-event dialog content
     if (rcmail.env.action == 'dialog-ui') {
       var date = new Date(), event = {allDay: false, calendar: me.selected_calendar};
 
       date.setHours(date.getHours()+1);
       date.setMinutes(0);
 
       var end = new Date(date.getTime());
       end.setHours(date.getHours()+1);
 
       event.start = date;
       event.end = end;
 
       // exec deferred because it must be after init_calendar_ui
       window.setTimeout(function() {
         event_edit_dialog('new', $.extend(event, rcmail.env.event_prop));
       }, exec_deferred);
 
       rcmail.register_command('event-save', function() { rcmail.env.event_save_func(); }, true);
       rcmail.addEventListener('plugin.unlock_saving', function(status) {
         me.unlock_saving();
         if (status)
           window.parent.kolab_event_dialog_element.dialog('destroy');
       });
     }
 } // end rcube_calendar class
 
 
 // Update layout after initialization
 // In devel mode we have to wait until all styles are applied by less
 if (rcmail.env.devel_mode && window.less) {
   less.pageLoadFinished.then(function() { $(window).resize(); });
 }
 
 /* calendar plugin initialization */
 window.rcmail && rcmail.addEventListener('init', function(evt) {
   // let's go
   var cal = new rcube_calendar_ui($.extend(rcmail.env.calendar_settings, rcmail.env.libcal_settings));
 
   if (rcmail.env.action == 'dialog-ui') {
     return;
   }
 
   // configure toolbar buttons
   rcmail.register_command('addevent', function(){ cal.add_event(); });
   rcmail.register_command('print', function(){ cal.print_calendars(); }, true);
 
   // configure list operations
   rcmail.register_command('calendar-create', function(){ cal.calendar_edit_dialog(null); }, true);
   rcmail.register_command('calendar-edit', function(){ cal.calendar_edit_dialog(cal.calendars[cal.selected_calendar]); }, false);
   rcmail.register_command('calendar-remove', function(){ cal.calendar_remove(cal.calendars[cal.selected_calendar]); }, false);
   rcmail.register_command('calendar-delete', function(){ cal.calendar_delete(cal.calendars[cal.selected_calendar]); }, false);
   rcmail.register_command('events-import', function(){ cal.import_events(cal.calendars[cal.selected_calendar]); }, true);
   rcmail.register_command('calendar-showurl', function(){ cal.showurl(cal.calendars[cal.selected_calendar]); }, false);
   rcmail.register_command('calendar-showfburl', function(){ cal.showfburl(); }, false);
   rcmail.register_command('event-download', function(){ cal.event_download(cal.selected_event); }, true);
   rcmail.register_command('event-sendbymail', function(p, obj, e){ cal.event_sendbymail(cal.selected_event, e); }, true);
   rcmail.register_command('event-copy', function(){ cal.event_copy(cal.selected_event); }, true);
   rcmail.register_command('event-history', function(p, obj, e){ cal.event_history_dialog(cal.selected_event); }, false);
 
   // search and export events
   rcmail.register_command('export', function(){ cal.export_events(cal.calendars[cal.selected_calendar]); }, true);
   rcmail.register_command('search', function(){ cal.quicksearch(); }, true);
   rcmail.register_command('reset-search', function(){ cal.reset_quicksearch(); }, true);
 
   // resource invitation dialog
   rcmail.register_command('search-resource', function(){ cal.resource_search(); }, true);
   rcmail.register_command('reset-resource-search', function(){ cal.reset_resource_search(); }, true);
   rcmail.register_command('add-resource', function(){ cal.add_resource2event(); }, false);
 
   // register callback commands
   rcmail.addEventListener('plugin.refresh_source', function(data) { cal.calendar_refresh_source(data); });
   rcmail.addEventListener('plugin.destroy_source', function(p){ cal.calendar_destroy_source(p.id); });
   rcmail.addEventListener('plugin.unlock_saving', function(p){ cal.unlock_saving(); });
   rcmail.addEventListener('plugin.refresh_calendar', function(p){ cal.refresh(p); });
   rcmail.addEventListener('plugin.import_success', function(p){ cal.import_success(p); });
   rcmail.addEventListener('plugin.import_error', function(p){ cal.import_error(p); });
   rcmail.addEventListener('plugin.update_counts', function(p){ cal.update_counts(p); });
   rcmail.addEventListener('plugin.reload_view', function(p){ cal.reload_view(p); });
   rcmail.addEventListener('plugin.resource_data', function(p){ cal.resource_data_load(p); });
   rcmail.addEventListener('plugin.resource_owner', function(p){ cal.resource_owner_load(p); });
   rcmail.addEventListener('plugin.render_event_changelog', function(data){ cal.render_event_changelog(data); });
   rcmail.addEventListener('plugin.event_show_diff', function(data){ cal.event_show_diff(data); });
   rcmail.addEventListener('plugin.close_history_dialog', function(data){ cal.close_history_dialog(); });
   rcmail.addEventListener('plugin.event_show_revision', function(data){ cal.event_show_dialog(data, null, true); });
   rcmail.addEventListener('plugin.itip_message_processed', function(data){ cal.itip_message_processed(data); });
   rcmail.addEventListener('requestrefresh', function(q){ return cal.before_refresh(q); });
 
   $(window).resize(function(e) {
     // check target due to bugs in jquery
     // http://bugs.jqueryui.com/ticket/7514
     // http://bugs.jquery.com/ticket/9841
     if (e.target == window) {
       cal.view_resize();
 
       // In Elastic append the datepicker back to sidebar/dialog when resizing
       // the window from tablet/phone to desktop and vice-versa
       var dp = $('#datepicker'), in_dialog = dp.is('.ui-dialog-content'), width = $(window).width();
       if (in_dialog && width > 768) {
         if (dp.is(':visible')) {
           dp.dialog('close');
         }
         dp.height('auto').removeClass('ui-dialog-content ui-widget-content')
           .data('dialog-parent', dp.closest('.ui-dialog'))
           .appendTo('#layout > div.sidebar');
       }
       else if (!in_dialog && dp.length && width <= 768 && dp.data('dialog-parent')) {
         dp.addClass('ui-dialog-content ui-widget-content')
           .insertAfter(dp.data('dialog-parent').find('.ui-dialog-titlebar'));
       }
     }
   }).resize();
 
   // show calendars list when ready
   $('#calendars').css('visibility', 'inherit');
 
   // show toolbar
   $('#toolbar').show();
 
   // Elastic mods
   if ($('#calendar').data('elastic-mode')) {
     var selector = $('<div class="btn-group btn-group-toggle" role="group">').appendTo('.fc-header-toolbar > .fc-left'),
         nav = $('<div class="btn-group btn-group-toggle" role="group">').appendTo('.fc-header-toolbar > .fc-right');
 
     $('.fc-header-toolbar > .fc-left button').each(function() {
       var new_btn, cl = 'btn btn-secondary', btn = $(this),
         activate = function(button) {
           selector.children('.active').removeClass('active');
           $(button).addClass('active');
         };
 
       if (btn.is('.fc-state-active')) {
         cl += ' active';
       }
 
       new_btn = $('<button>').attr({'class': cl, type: 'button'}).text(btn.text())
         .appendTo(selector)
         .on('click', function() {
           activate(this);
           btn.click();
         });
 
       if (window.MutationObserver) {
         // handle button active state changes
         new MutationObserver(function() { if (btn.is('.fc-state-active')) activate(new_btn); }).observe(this, {attributes: true});
       }
     });
 
     $.each(['prev', 'today', 'next'], function() {
       var btn = $('.fc-header-toolbar > .fc-right').find('.fc-' + this + '-button');
       $('<button>').attr({'class': 'btn btn-secondary ' + this, type: 'button'})
         .text(btn.text()).appendTo(nav).on('click', function() { btn.click(); });
     });
 
     $('#timezone-display').appendTo($('.fc-header-toolbar > .fc-center')).removeClass('hidden');
     $('#agendaoptions').detach().insertAfter('.fc-header-toolbar');
 
     $('.content-frame-navigation a.button.date').appendTo('.content > .searchbar');
 
     // Mobile header title
     if (window.MutationObserver) {
       var title = $('.fc-header-toolbar > .fc-center h2'),
         mobile_header = $('#layout > .content > .header > .header-title'),
         callback = function() {
           var text = title.text();
           mobile_header.html('').append([
             $('<span class="title">').text(text),
             $('<span class="tz">').text($('#timezone-display').text())
           ]);
         };
 
       // update the header when something changes on the calendar title
       new MutationObserver(callback).observe(title[0], {childList: true, subtree: true});
       // initialize the header
       callback();
     }
 
     window.calendar_datepicker = function() {
       $('#datepicker').dialog({
         modal: true,
         title: rcmail.gettext('calendar.selectdate'),
         buttons: [{
           text: rcmail.gettext('close', 'calendar'),
           'class': 'cancel',
           click: function() { $(this).dialog('close'); }
         }],
         width: 400,
         height: 520
       });
     }
   }
 });
diff --git a/plugins/calendar/lib/calendar_ui.php b/plugins/calendar/lib/calendar_ui.php
index 8be700c4..7a534d5e 100644
--- a/plugins/calendar/lib/calendar_ui.php
+++ b/plugins/calendar/lib/calendar_ui.php
@@ -1,881 +1,870 @@
 <?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',
       'type'       => 'link'
       ), 'taskbar');
     
     // load basic client script
     if ($this->rc->action != 'print') {
       $this->cal->include_script('calendar_base.js');
     }
 
     $this->addCSS();
 
     $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'));
     $this->cal->register_handler('plugin.attendees_list', array($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'));
     $this->cal->register_handler('plugin.edit_recurrence_sync', array($this, 'edit_recurrence_sync'));
     $this->cal->register_handler('plugin.edit_recurring_warning', array($this, 'recurring_event_warning'));
     $this->cal->register_handler('plugin.event_rsvp_buttons', array($this, 'event_rsvp_buttons'));
     $this->cal->register_handler('plugin.agenda_options', array($this, 'agenda_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
 
     kolab_attachments_handler::ui();
   }
 
   /**
    * Adds CSS stylesheets to the page header
    */
   public function addCSS()
   {
     $skin_path = $this->cal->local_skin_path();
  
     if ($this->rc->task == 'calendar' && (!$this->rc->action || in_array($this->rc->action, array('index', 'print')))) {
       // Include fullCalendar style before skin file for simpler style overriding
       $this->cal->include_stylesheet($skin_path . '/fullcalendar.css');
     }
 
     $this->cal->include_stylesheet($skin_path . '/calendar.css');
 
     if ($this->rc->task == 'calendar' && $this->rc->action == 'print') {
       $this->cal->include_stylesheet($skin_path . '/print.css');
     }
   }
 
   /**
    * Adds JS files to the page header
    */
   public function addJS()
   {
     $this->cal->include_script('lib/js/moment.js');
     $this->cal->include_script('lib/js/fullcalendar.js');
 
     if ($this->rc->task == 'calendar' && $this->rc->action == 'print') {
       $this->cal->include_script('print.js');
     }
     else {
       $this->rc->output->include_script('treelist.js');
       $this->cal->api->include_script('libkolab/libkolab.js');
       $this->cal->include_script('calendar_ui.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, $attrib);
     }
     
     return html::tag('style', array('type' => 'text/css'), $css);
   }
 
   /**
    *
    */
   public function calendar_css_classes($id, $prop, $mode, $attrib = array())
   {
     $color = $folder_color = $prop['color'];
 
     // replace white with skin-defined color
     if (!empty($attrib['folder-fallback-color']) && preg_match('/^f+$/i', $folder_color)) {
         $folder_color = $attrib['folder-fallback-color'];
     }
 
     $class = 'cal-' . asciiwords($id, true);
     $css   = str_replace('$class', $class, $attrib['folder-class']) ?: "li .$class";
     $css  .= ", #eventshow .$class { color: #$folder_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 (!$prop['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(), $js_only = false)
   {
     $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);
 
     if ($js_only) {
       return;
     }
 
     $this->rc->output->set_env('source', rcube_utils::get_input_value('source', rcube_utils::INPUT_GET));
     $this->rc->output->add_gui_object('calendarslist', $attrib['id'] ?: 'unknown');
 
     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::a(array('class' => 'calname', 'id' => $label_id, 'title' => $title, 'href' => '#'), rcube::Q($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;
   }
 
   /**
    * Render a HTML for agenda options form
    */
   function agenda_options($attrib = array())
   {
     $attrib += array('id' => 'agendaoptions');
     $attrib['style'] .= 'display:none';
 
     $select_range = new html_select(array('name' => 'listrange', 'id' => 'agenda-listrange', 'class' => 'form-control custom-select'));
     $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::span('input-group',
         html::label(array('for' => 'agenda-listrange', 'class' => 'input-group-prepend'),
             html::span('input-group-text', $this->cal->gettext('listrange')))
         . $select_range->show($this->rc->config->get('calendar_agenda_range', $this->cal->defaults['calendar_agenda_range']))
     );
-/*
-    $select_sections = new html_select(array('name' => 'listsections', 'id' => 'agenda-listsections', 'class' => 'form-control custom-select'));
-    $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('input-group',
-        html::label(array('for' => 'agenda-listsections', 'class' => 'input-group-prepend'),
-            html::span('input-group-text', $this->cal->gettext('listsections')))
-        . $select_sections->show($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('status-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);
   }
 
   /**
    * Render HTML for attendee notification warning
    */
   function edit_attendees_notify($attrib = array())
   {
     $checkbox = new html_checkbox(array('name' => '_notify', 'id' => 'edit-attendees-donotify', 'value' => 1, 'class' => 'pretty-checkbox'));
     return html::div($attrib, html::label(null, $checkbox->show(1) . ' ' . $this->cal->gettext('sendnotifications')));
   }
 
   /**
    * Render HTML for recurrence option to align start date with the recurrence rule
    */
   function edit_recurrence_sync($attrib = array())
   {
     $checkbox = new html_checkbox(array('name' => '_start_sync', 'value' => 1, 'class' => 'pretty-checkbox'));
     return html::div($attrib, html::label(null, $checkbox->show(1) . ' ' . $this->cal->gettext('eventstartsync')));
   }
 
   /**
    * 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', $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 = $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));
 
     $html = html::div('form-section form-group row',
       html::label(array('class' => 'col-sm-4 col-form-label', 'for' => 'importfile'), rcube::Q($this->rc->gettext('importfromfile')))
       . html::div('col-sm-8', $input->show()
         . html::div('hint', $this->rc->gettext(array('id' => 'importfile', 'name' => 'maxuploadsize', 'vars' => array('size' => $max_filesize)))))
     );
 
     $html .= html::div('form-section form-group row',
       html::label(array('for' => 'event-import-calendar', 'class' => 'col-form-label col-sm-4'), $this->cal->gettext('calendar'))
       . html::div('col-sm-8', $this->calendar_select(array('name' => 'calendar', 'id' => 'event-import-calendar')))
     );
 
     $html .= html::div('form-section form-group row',
       html::label(array('for' => 'event-import-range', 'class' => 'col-form-label col-sm-4'), $this->cal->gettext('importrange'))
       . html::div('col-sm-8', $select->show(1))
     );
 
     $this->rc->output->add_gui_object('importform', $attrib['id']);
     $this->rc->output->add_label('import');
 
     return html::tag('p', null, $this->cal->gettext('importtext'))
       . 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 form-group row',
       html::label(array('for' => 'event-export-calendar', 'class' => 'col-sm-4 col-form-label'), $this->cal->gettext('calendar'))
         . html::div('col-sm-8', $this->calendar_select(array('name' => 'calendar', 'id' => 'event-export-calendar', 'class' => 'form-control custom-select'))));
 
     $select = new html_select(array('name' => 'range', 'id' => 'event-export-range', 'class' => 'form-control custom-select'));
     $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 form-group row',
       html::label(array('for' => 'event-export-range', 'class' => 'col-sm-4 col-form-label'), $this->cal->gettext('exportrange'))
         . html::div('col-sm-8', $select->show(0) . html::span(array('style'=>'display:none'), $startdate->show())));
 
     $checkbox = new html_checkbox(array('name' => 'attachments', 'id' => 'event-export-attachments', 'value' => 1, 'class' => 'form-check-input pretty-checkbox'));
     $html .= html::div('form-section form-check row',
       html::label(array('for' => 'event-export-attachments', 'class' => 'col-sm-4 col-form-label'), $this->cal->gettext('exportattachments'))
         . html::div('col-sm-8', $checkbox->show(1)));
 
     $this->rc->output->add_gui_object('exportform', $attrib['id']);
 
     return html::tag('form', $attrib + array(
         'action' => $this->rc->url(array('task' => 'calendar', 'action' => 'export_events')),
         'method' => "post",
         'id' => $attrib['id']
       ),
       $html
     );
   }
 
   /**
    * Handler for calendar form template.
    * The form content could be overriden by the driver
    */
   function calendar_editform($action, $calendar = array())
   {
     $this->action   = $action;
     $this->calendar = $calendar;
 
     // load miniColors js/css files
     jqueryui::miniColors();
 
     $this->rc->output->set_env('pagetitle', $this->cal->gettext('calendarprops'));
     $this->rc->output->add_handler('folderform', array($this, 'calendarform'));
     $this->rc->output->send('libkolab.folderform');
   }
 
   /**
    * Handler for calendar form template.
    * The form content could be overriden by the driver
    */
   function calendarform($attrib)
   {
     // 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' => 7, 'class' => 'colors'));
 
     $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' => $checkbox->show($this->calendar['showalarms'] ? 1 :0),
         'id'    => 'calendar-showalarms',
       );
     }
 
     // allow driver to extend or replace the form content
     return html::tag('form', $attrib + array('action' => "#", 'method' => "get", 'id' => 'calendarpropform'),
       $this->cal->driver->calendar_form($this->action, $this->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', html::span('inner', $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', 'class' => 'form-control'));
     $textarea = new html_textarea(array('name' => 'comment', 'id' => 'edit-attendees-comment', 'class' => 'form-control',
         'rows' => 4, 'cols' => 55, 'title' => $this->cal->gettext('itipcommenttitle')));
 
     return html::div($attrib,
       html::div('form-searchbar', $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('edit-attendees-comment', $this->cal->gettext('itipcomment')) . $textarea->show())
     );
   }
 
   /**
    *
    */
   function resources_form($attrib = array())
   {
     $input = new html_inputfield(array('name' => 'resource', 'id' => 'edit-resource-name', 'class' => 'form-control'));
 
     return html::div($attrib,
       html::div('form-searchbar', $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',
         'reset-command' => 'reset-resource-search',
         'id'            => 'rcmcalresqsearchbox',
         'autocomplete'  => 'off',
         'form-name'     => 'rcmcalresoursqsearchform',
         'gui-object'    => 'resourcesearchform',
     );
 
     // add form tag around text field
     return $this->rc->output->search_form($attrib);
   }
 
   /**
    *
    */
   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);
   }
 
 }