diff --git a/action/ajax.php b/action/ajax.php
--- a/action/ajax.php
+++ b/action/ajax.php
@@ -1,202 +1,199 @@
 <?php
 
 /**
  * DokuWiki DAVCal PlugIn - Ajax component
  */
 
 if(!defined('DOKU_INC')) die();
 
 class action_plugin_davcal_ajax extends DokuWiki_Action_Plugin {
 
     /**
      * @var helper_plugin_davcal
      */
     private $hlp = null;
 
     function __construct() {
         $this->hlp =& plugin_load('helper','davcal');
     }
 
     function register(Doku_Event_Handler $controller) {
         $controller->register_hook('AJAX_CALL_UNKNOWN', 'BEFORE', $this, 'handle_ajax_call_unknown');
     }
 
     function handle_ajax_call_unknown(&$event, $param) {
       if($event->data != 'plugin_davcal') return;
       
       $event->preventDefault();
       $event->stopPropagation();
       global $INPUT;
       
       $action = trim($INPUT->post->str('action'));
       $id = trim($INPUT->post->str('id'));
       $page = trim($INPUT->post->str('page'));
       $params = $INPUT->post->arr('params');
       if(isset($_SERVER['REMOTE_USER']) && !is_null($_SERVER['REMOTE_USER']))
         $user = $_SERVER['REMOTE_USER'];
       else
         $user = null;
       $write = false;
-      $multi = false;
-      
+         
       if(!checkSecurityToken())
       {
           echo "CSRF Attack.";
           return;
       }
       
       $data = array();
       
       $data['result'] = false;
       $data['html'] = $this->getLang('unknown_error');
       
       // Check if we have access to the calendar ($id is given by parameters,
       // that's not necessarily the page we come from)
-      $acl = auth_quickaclcheck($id);
+      
+      $acl = $this->hlp->checkCalendarPermission($id);
       if($acl > AUTH_READ)
       {
           $write = true;
       }
       elseif($acl < AUTH_READ)
       {
           $data['result'] = false;
           $data['html'] = $this->getLang('no_permission');
           // Set to an invalid action in order to just return the result
           $action = 'invalid';
       }
       
       // Retrieve the calendar pages based on the meta data
       $calendarPages = $this->hlp->getCalendarPagesByMeta($page);
       if($calendarPages === false)
       {
           $calendarPages = array($page => null);
       }
-      if(count($calendarPages) > 1)
-        $multi = true;
       
       // Parse the requested action
       switch($action)
       {
           // Add a new Event
           case 'newEvent':
               if($write)
               {
                   $res = $this->hlp->addCalendarEntryToCalendarForPage($id, $user, $params);
                   if($res === true)
                   {
                     $data['result'] = true;
                     $data['html'] = $this->getLang('event_added');
                   }
                   else
                   {
                     $data['result'] = false;
                     $data['html'] = $this->getLang('unknown_error');
                   }
               }
               else
               {
                   $data['result'] = false;
                   $data['html'] = $this->getLang('no_permission');
               }
           break;
           // Retrieve existing Events
           case 'getEvents':
               $startDate = $INPUT->post->str('start');
               $endDate = $INPUT->post->str('end');
               $timezone = $INPUT->post->str('timezone');
               $data = array();
               foreach($calendarPages as $calPage => $color)
               {
                   $data = array_merge($data, $this->hlp->getEventsWithinDateRange($calPage, 
                                       $user, $startDate, $endDate, $timezone, $color)); 
               }
           break;
           // Edit an event
           case 'editEvent':
               if($write)
               {
                   $res = $this->hlp->editCalendarEntryForPage($id, $user, $params);
                   if($res === true)
                   {
                     $data['result'] = true;
                     $data['html'] = $this->getLang('event_edited');
                   }
                   else
                   {
                     $data['result'] = false;
                     $data['html'] = $this->getLang('unknown_error');
                   }
               }
               else
               {
                   $data['result'] = false;
                   $data['html'] = $this->getLang('no_permission');
               }
           break;
           // Delete an Event
           case 'deleteEvent':
               if($write)
               {
                   $res = $this->hlp->deleteCalendarEntryForPage($id, $params);
                   if($res === true)
                   {
                     $data['result'] = true;
                     $data['html'] = $this->getLang('event_deleted');
                   }
                   else
                   {
                     $data['result'] = false;
                     $data['html'] = $this->getLang('unknown_error');
                   }
               }
               else 
               {
                   $data['result'] = false;
                   $data['html'] = $this->getLang('no_permission');
               }
           break;
           // Get personal settings
           case 'getSettings':
               $data['result'] = true;
               $data['settings'] = $this->hlp->getPersonalSettings($user);
-              $data['settings']['multi'] = $multi;
               $data['settings']['calids'] = $this->hlp->getCalendarMapForIDs($calendarPages);
               $data['settings']['readonly'] = !$write;
               $data['settings']['syncurl'] = $this->hlp->getSyncUrlForPage($page, $user);
               $data['settings']['privateurl'] = $this->hlp->getPrivateURLForPage($page);
               $data['settings']['principalurl'] = $this->hlp->getPrincipalUrlForUser($user);
               $data['settings']['meta'] = $this->hlp->getCalendarMetaForPage($page);
           break;
           // Save personal settings
           case 'saveSettings':
               $settings = array();
               $settings['weeknumbers'] = $params['weeknumbers'];
               $settings['timezone'] = $params['timezone'];
               $settings['workweek'] = $params['workweek'];
               $settings['monday'] = $params['monday'];
               $settings['timeformat'] = $params['timeformat'];
               if($this->hlp->savePersonalSettings($settings, $user))
               {
                   $data['result'] = true;
                   $data['html'] = $this->getLang('settings_saved');
               }
               else
               {
                   $data['result'] = false;
                   $data['html'] = $this->getLang('error_saving');
               }
           break;
       }
     
       // If we are still here, JSON output is requested
       
       //json library of DokuWiki
       require_once DOKU_INC . 'inc/JSON.php';
       $json = new JSON();
  
       //set content type
       header('Content-Type: application/json');
       echo $json->encode($data);            
     }
  
 }              
diff --git a/helper.php b/helper.php
--- a/helper.php
+++ b/helper.php
@@ -1,1730 +1,1762 @@
 <?php
 /** 
   * Helper Class for the DAVCal plugin
   * This helper does the actual work.
   * 
   */
   
 // must be run within Dokuwiki
 if(!defined('DOKU_INC')) die();
 
 class helper_plugin_davcal extends DokuWiki_Plugin {
   
   protected $sqlite = null;
   protected $cachedValues = array();
   
   /**
     * Constructor to load the configuration and the SQLite plugin
     */
   public function helper_plugin_davcal() {
     $this->sqlite =& plugin_load('helper', 'sqlite');
     global $conf;
     if($conf['allowdebug'])
         dbglog('---- DAVCAL helper.php init');
     if(!$this->sqlite)
     {
         if($conf['allowdebug'])
             dbglog('This plugin requires the sqlite plugin. Please install it.');
         msg('This plugin requires the sqlite plugin. Please install it.');
         return;
     }
     
     if(!$this->sqlite->init('davcal', DOKU_PLUGIN.'davcal/db/'))
     {
         if($conf['allowdebug'])
             dbglog('Error initialising the SQLite DB for DAVCal');
         return;
     }
   }
   
   /**
    * Retrieve meta data for a given page
    * 
    * @param string $id optional The page ID
    * @return array The metadata
    */
   private function getMeta($id = null) {
     global $ID;
     global $INFO;
 
     if ($id === null) $id = $ID;
 
     if($ID === $id && $INFO['meta']) {
         $meta = $INFO['meta'];
     } else {
         $meta = p_get_metadata($id);
     }
     
     return $meta;
   }
   
   /**
    * Retrieve the meta data for a given page
    * 
    * @param string $id optional The page ID
    * @return array with meta data
    */
   public function getCalendarMetaForPage($id = null)
   {
       if(is_null($id))
       {
           global $ID;
           $id = $ID;
       }
       
       $meta = $this->getMeta($id);
       if(isset($meta['plugin_davcal']))
         return $meta['plugin_davcal'];
       else
         return array();
   }
   
   /**
+   * Check the permission of a user for a given calendar ID
+   * 
+   * @param string $id The calendar ID to check
+   * @return int AUTH_* constants
+   */
+  public function checkCalendarPermission($id)
+  {
+      if(strpos($page, 'webdav://') === 0)
+      {
+          $wdc =& plugin_load('helper', 'webdavclient');
+          if(is_null($wdc))
+            return AUTH_NONE;
+          $connectionId = str_replace('webdav://', '', $page);
+          $settings = $wdc->getConnection($connectionId);
+          if($settings === false)
+            return AUTH_NONE;
+          if($settings['write'] === '1')
+            return AUTH_CREATE;
+          return AUTH_READ;
+      }
+      else
+      {
+          $calid = $this->getCalendarIdForPage($id);
+          // We return AUTH_READ if the calendar does not exist. This makes
+          // davcal happy when there are just included calendars
+          if($calid === false)
+            return AUTH_READ;
+          return auth_quickaclcheck($id);
+      }
+  }
+  
+  /**
    * Filter calendar pages and return only those where the current
    * user has at least read permission.
    * 
    * @param array $calendarPages Array with calendar pages to check
    * @return array with filtered calendar pages
    */
   public function filterCalendarPagesByUserPermission($calendarPages)
   {
       $retList = array();
       foreach($calendarPages as $page => $data)
       {
           // WebDAV Connections are always readable
           if(strpos($page, 'webdav://') === 0)
           {
               $retList[$page] = $data;
           }
           elseif(auth_quickaclcheck($page) >= AUTH_READ)
           {
               $retList[$page] = $data;
           }
       }
       return $retList;
   }
   
   /**
    * Get all calendar pages used by a given page
    * based on the stored metadata
    * 
    * @param string $id optional The page id
    * @return mixed The pages as array or false
    */
   public function getCalendarPagesByMeta($id = null)
   {
       if(is_null($id))
       {
           global $ID;
           $id = $ID;
       }
       
       $meta = $this->getCalendarMetaForPage($id);
 
       if(isset($meta['id']))
       {
           // Filter the list of pages by permission
           $pages = $this->filterCalendarPagesByUserPermission($meta['id']);
           if(empty($pages))
             return false;
           return $pages;
       }
       return false;
   }
   
   /**
    * Get a list of calendar names/pages/ids/colors
    * for an array of page ids
    * 
    * @param array $calendarPages The calendar pages to retrieve
    * @return array The list
    */
   public function getCalendarMapForIDs($calendarPages)
   {
       $data = array();
       foreach($calendarPages as $page => $color)
       {
             if(strpos($page, 'webdav://') === 0)
             {
                 $wdc =& plugin_load('helper', 'webdavclient');
                 if(is_null($wdc))
                     continue;
                 $connectionId = str_replace('webdav://', '', $page);
                 $settings = $wdc->getConnection($connectionId);
                 if($settings === false)
                     continue;
                 $name = $settings['displayname'];
-                $write = $settings['write'];
+                $write = ($settings['write'] === '1');
                 $calid = $connectionId;
             }
             else
             {
                 $calid = $this->getCalendarIdForPage($page);
                 if($calid !== false)
                 {
                     $settings = $this->getCalendarSettings($calid);
                     $name = $settings['displayname'];
                     //$color = $settings['calendarcolor'];
                     $write = (auth_quickaclcheck($page) > AUTH_READ);
                 }
                 else
                 {
                     continue;
                 }
             }
             $data[] = array('name' => $name, 'page' => $page, 'calid' => $calid,
                             'color' => $color, 'write' => $write);
       }
       return $data;
   }
   
   /**
    * Get the saved calendar color for a given page.
    * 
    * @param string $id optional The page ID
    * @return mixed The color on success, otherwise false
    */
   public function getCalendarColorForPage($id = null)
   {
       if(is_null($id))
       {
           global $ID;
           $id = $ID;
       }
       
       $calid = $this->getCalendarIdForPage($id);
       if($calid === false)
         return false;
       
       return $this->getCalendarColorForCalendar($calid);
   }
   
   /**
    * Get the saved calendar color for a given calendar ID.
    * 
    * @param string $id optional The calendar ID
    * @return mixed The color on success, otherwise false
    */
   public function getCalendarColorForCalendar($calid)
   {
       if(isset($this->cachedValues['calendarcolor'][$calid]))
         return $this->cachedValues['calendarcolor'][$calid];
 
       $row = $this->getCalendarSettings($calid);
 
       if(!isset($row['calendarcolor']))
         return false;
       
       $color = $row['calendarcolor'];
       $this->cachedValues['calendarcolor'][$calid] = $color;
       return $color;
   }
   
   /**
    * Get the user's principal URL for iOS sync
    * @param string $user the user name
    * @return the URL to the principal sync
    */
   public function getPrincipalUrlForUser($user)
   {
       if(is_null($user))
         return false;
       $url = DOKU_URL.'lib/plugins/davcal/calendarserver.php/principals/'.$user;
       return $url;
   }
   
   /**
    * Set the calendar color for a given page.
    * 
    * @param string $color The color definition
    * @param string $id optional The page ID
    * @return boolean True on success, otherwise false
    */
   public function setCalendarColorForPage($color, $id = null)
   {
       if(is_null($id))
       {
           global $ID;
           $id = $ID;
       }
       $calid = $this->getCalendarIdForPage($id);
       if($calid === false)
         return false;
       
       $query = "UPDATE calendars SET calendarcolor = ? ".
                " WHERE id = ?";
       $res = $this->sqlite->query($query, $color, $calid);
       if($res !== false)
       {
         $this->cachedValues['calendarcolor'][$calid] = $color;
         return true;
       }
       return false;
   }
   
   /**
    * Set the calendar name and description for a given page with a given
    * page id.
    * If the calendar doesn't exist, the calendar is created!
    * 
    * @param string  $name The name of the new calendar
    * @param string  $description The description of the new calendar
    * @param string  $id (optional) The ID of the page
    * @param string  $userid The userid of the creating user
    * 
    * @return boolean True on success, otherwise false.
    */
   public function setCalendarNameForPage($name, $description, $id = null, $userid = null)
   {
       if(is_null($id))
       {
           global $ID;
           $id = $ID;
       }
       if(is_null($userid))
       {
         if(isset($_SERVER['REMOTE_USER']) && !is_null($_SERVER['REMOTE_USER']))
         {
           $userid = $_SERVER['REMOTE_USER'];
         }
         else
         {
           $userid = uniqid('davcal-');
         }
       }
       $calid = $this->getCalendarIdForPage($id);
       if($calid === false)
         return $this->createCalendarForPage($name, $description, $id, $userid);
       
       $query = "UPDATE calendars SET displayname = ?, description = ? WHERE id = ?";
       $res = $this->sqlite->query($query, $name, $description, $calid);
       if($res !== false)
         return true;
       return false;
   }
   
   /**
    * Update a calendar's displayname
    * 
    * @param int $calid The calendar's ID
    * @param string $name The new calendar name
    * 
    * @return boolean True on success, otherwise false
    */
   public function updateCalendarName($calid, $name)
   {
       $query = "UPDATE calendars SET displayname = ? WHERE id = ?";
       $res = $this->sqlite->query($query, $calid, $name);
       if($res !== false)
       {
         $this->updateSyncTokenLog($calid, '', 'modified');
         return true;
       }
       return false;
   }
   
   /**
    * Update the calendar description
    * 
    * @param int $calid The calendar's ID
    * @param string $description The new calendar's description
    * 
    * @return boolean True on success, otherwise false
    */
   public function updateCalendarDescription($calid, $description)
   {
       $query = "UPDATE calendars SET description = ? WHERE id = ?";
       $res = $this->sqlite->query($query, $calid, $description);
       if($res !== false)
       {
         $this->updateSyncTokenLog($calid, '', 'modified');
         return true;
       }
       return false;
   }
   
   /**
    * Update a calendar's timezone information
    * 
    * @param int $calid The calendar's ID
    * @param string $timezone The new timezone to set
    * 
    * @return boolean True on success, otherwise false
    */
   public function updateCalendarTimezone($calid, $timezone)
   {
       $query = "UPDATE calendars SET timezone = ? WHERE id = ?";
       $res = $this->sqlite->query($query, $calid, $timezone);
       if($res !== false)
       {
         $this->updateSyncTokenLog($calid, '', 'modified');
         return true;
       }
       return false;
   }
   
   /**
    * Save the personal settings to the SQLite database 'calendarsettings'.
    * 
    * @param array  $settings The settings array to store
    * @param string $userid (optional) The userid to store
    * 
    * @param boolean True on success, otherwise false
    */
   public function savePersonalSettings($settings, $userid = null)
   {
       if(is_null($userid))
       {
           if(isset($_SERVER['REMOTE_USER']) && !is_null($_SERVER['REMOTE_USER']))
           {
             $userid = $_SERVER['REMOTE_USER'];
           }
           else 
           {
               return false;
           }
       }
       $this->sqlite->query("BEGIN TRANSACTION");
       
       $query = "DELETE FROM calendarsettings WHERE userid = ?";
       $this->sqlite->query($query, $userid);
       
       foreach($settings as $key => $value)
       {
           $query = "INSERT INTO calendarsettings (userid, key, value) VALUES (?, ?, ?)";
           $res = $this->sqlite->query($query, $userid, $key, $value);
           if($res === false)
               return false;
       }
       $this->sqlite->query("COMMIT TRANSACTION");
       $this->cachedValues['settings'][$userid] = $settings;
       return true;
   }
   
   /**
    * Retrieve the settings array for a given user id. 
    * Some sane defaults are returned, currently:
    * 
    *    timezone    => local
    *    weeknumbers => 0
    *    workweek    => 0
    * 
    * @param string $userid (optional) The user id to retrieve
    * 
    * @return array The settings array
    */
   public function getPersonalSettings($userid = null)
   {
       // Some sane default settings
       $settings = array(
         'timezone' => $this->getConf('timezone'),
         'weeknumbers' => $this->getConf('weeknumbers'),
         'workweek' => $this->getConf('workweek'),
         'monday' => $this->getConf('monday'),
         'timeformat' => $this->getConf('timeformat')
       );
       if(is_null($userid))
       {
           if(isset($_SERVER['REMOTE_USER']) && !is_null($_SERVER['REMOTE_USER']))
           {
             $userid = $_SERVER['REMOTE_USER'];
           }
           else 
           {
             return $settings;
           }
       }
 
       if(isset($this->cachedValues['settings'][$userid]))
         return $this->cachedValues['settings'][$userid];
       $query = "SELECT key, value FROM calendarsettings WHERE userid = ?";
       $res = $this->sqlite->query($query, $userid);
       $arr = $this->sqlite->res2arr($res);
       foreach($arr as $row)
       {
           $settings[$row['key']] = $row['value'];
       }
       $this->cachedValues['settings'][$userid] = $settings;
       return $settings;
   }
   
   /**
    * Retrieve the calendar ID based on a page ID from the SQLite table
    * 'pagetocalendarmapping'. 
    * 
    * @param string $id (optional) The page ID to retrieve the corresponding calendar
    * 
    * @return mixed the ID on success, otherwise false
    */
   public function getCalendarIdForPage($id = null)
   {
       if(is_null($id))
       {
           global $ID;
           $id = $ID;
       }
       
       if(isset($this->cachedValues['calid'][$id]))
         return $this->cachedValues['calid'][$id];
       
       $query = "SELECT calid FROM pagetocalendarmapping WHERE page = ?";
       $res = $this->sqlite->query($query, $id);
       $row = $this->sqlite->res2row($res);
       if(isset($row['calid']))
       {
         $calid = $row['calid'];
         $this->cachedValues['calid'] = $calid;
         return $calid;
       }
       return false;
   }
   
   /**
    * Retrieve the complete calendar id to page mapping.
    * This is necessary to be able to retrieve a list of
    * calendars for a given user and check the access rights.
    * 
    * @return array The mapping array
    */
   public function getCalendarIdToPageMapping()
   {
       $query = "SELECT calid, page FROM pagetocalendarmapping";
       $res = $this->sqlite->query($query);
       $arr = $this->sqlite->res2arr($res);
       return $arr;
   }
   
   /**
    * Retrieve all calendar IDs a given user has access to.
    * The user is specified by the principalUri, so the
    * user name is actually split from the URI component.
    * 
    * Access rights are checked against DokuWiki's ACL
    * and applied accordingly.
    * 
    * @param string $principalUri The principal URI to work on
    * 
    * @return array An associative array of calendar IDs
    */
   public function getCalendarIdsForUser($principalUri)
   {
       global $auth;
       $user = explode('/', $principalUri);
       $user = end($user);
       $mapping = $this->getCalendarIdToPageMapping();
       $calids = array();
       $ud = $auth->getUserData($user);
       $groups = $ud['grps'];      
       foreach($mapping as $row)
       {
           $id = $row['calid'];
           $page = $row['page'];
           $acl = auth_aclcheck($page, $user, $groups);
           if($acl >= AUTH_READ)
           {
               $write = $acl > AUTH_READ;
               $calids[$id] = array('readonly' => !$write);
           }
       }
       return $calids;
   }
   
   /**
    * Create a new calendar for a given page ID and set name and description
    * accordingly. Also update the pagetocalendarmapping table on success.
    * 
    * @param string $name The calendar's name
    * @param string $description The calendar's description
    * @param string $id (optional) The page ID to work on
    * @param string $userid (optional) The user ID that created the calendar
    * 
    * @return boolean True on success, otherwise false
    */
   public function createCalendarForPage($name, $description, $id = null, $userid = null)
   {
       if(is_null($id))
       {
           global $ID;
           $id = $ID;
       }
       if(is_null($userid))
       {
         if(isset($_SERVER['REMOTE_USER']) && !is_null($_SERVER['REMOTE_USER']))
         {
           $userid = $_SERVER['REMOTE_USER'];
         }
         else
         {
           $userid = uniqid('davcal-');
         }
       }
       $values = array('principals/'.$userid, 
                       $name,
                       str_replace(array('/', ' ', ':'), '_', $id), 
                       $description,
                       'VEVENT,VTODO',
                       0,
                       1);
       $query = "INSERT INTO calendars (principaluri, displayname, uri, description, components, transparent, synctoken) ".
                "VALUES (?, ?, ?, ?, ?, ?, ?)";
       $res = $this->sqlite->query($query, $values[0], $values[1], $values[2], $values[3], $values[4], $values[5], $values[6]);
       if($res === false)
         return false;
       
       // Get the new calendar ID
       $query = "SELECT id FROM calendars WHERE principaluri = ? AND displayname = ? AND ".
                "uri = ? AND description = ?";
       $res = $this->sqlite->query($query, $values[0], $values[1], $values[2], $values[3]);
       $row = $this->sqlite->res2row($res);
       
       // Update the pagetocalendarmapping table with the new calendar ID
       if(isset($row['id']))
       {
           $query = "INSERT INTO pagetocalendarmapping (page, calid) VALUES (?, ?)";
           $res = $this->sqlite->query($query, $id, $row['id']);
           return ($res !== false);
       }
       
       return false;
   }
 
   /**
    * Add a new calendar entry to the given calendar. Calendar data is
    * specified as ICS file, thus it needs to be parsed first.
    * 
    * This is mainly needed for the sync support.
    * 
    * @param int $calid The calendar's ID
    * @param string $uri The new object URI
    * @param string $ics The ICS file
    * 
    * @return mixed The etag.
    */
   public function addCalendarEntryToCalendarByICS($calid, $uri, $ics)
   {
     $extraData = $this->getDenormalizedData($ics);
 
     $query = "INSERT INTO calendarobjects (calendarid, uri, calendardata, lastmodified, etag, size, componenttype, firstoccurence, lastoccurence, uid) VALUES (?,?,?,?,?,?,?,?,?,?)";
     $res = $this->sqlite->query($query, 
             $calid,
             $uri,
             $ics,
             time(),
             $extraData['etag'],
             $extraData['size'],
             $extraData['componentType'],
             $extraData['firstOccurence'],
             $extraData['lastOccurence'],
             $extraData['uid']);
             // If successfully, update the sync token database
     if($res !== false)
     {
         $this->updateSyncTokenLog($calid, $uri, 'added');
     }
     return $extraData['etag'];
   }
   
   /**
    * Edit a calendar entry by providing a new ICS file. This is mainly
    * needed for the sync support.
    * 
    * @param int $calid The calendar's IS
    * @param string $uri The object's URI to modify
    * @param string $ics The new object's ICS file
    */
   public function editCalendarEntryToCalendarByICS($calid, $uri, $ics)
   {
       $extraData = $this->getDenormalizedData($ics);
 
       $query = "UPDATE calendarobjects SET calendardata = ?, lastmodified = ?, etag = ?, size = ?, componenttype = ?, firstoccurence = ?, lastoccurence = ?, uid = ? WHERE calendarid = ? AND uri = ?";
       $res = $this->sqlite->query($query, 
         $ics,
         time(),
         $extraData['etag'],
         $extraData['size'],
         $extraData['componentType'],
         $extraData['firstOccurence'], 
         $extraData['lastOccurence'], 
         $extraData['uid'], 
         $calid,
         $uri
       );
       if($res !== false)
       {
           $this->updateSyncTokenLog($calid, $uri, 'modified');
       }
       return $extraData['etag'];
   }
 
   /**
    * Add a new iCal entry for a given page, i.e. a given calendar.
    * 
    * The parameter array needs to contain
    *   detectedtz       => The timezone as detected by the browser
    *   currenttz        => The timezone in use by the calendar
    *   eventfrom        => The event's start date
    *   eventfromtime    => The event's start time
    *   eventto          => The event's end date
    *   eventtotime      => The event's end time
    *   eventname        => The event's name
    *   eventdescription => The event's description
    * 
    * @param string $id The page ID to work on
    * @param string $user The user who created the calendar
    * @param string $params A parameter array with values to create
    * 
    * @return boolean True on success, otherwise false
    */
   public function addCalendarEntryToCalendarForPage($id, $user, $params)
   {
       if($params['currenttz'] !== '' && $params['currenttz'] !== 'local')
           $timezone = new \DateTimeZone($params['currenttz']);
       elseif($params['currenttz'] === 'local')
           $timezone = new \DateTimeZone($params['detectedtz']);
       else
           $timezone = new \DateTimeZone('UTC');
       
       // Retrieve dates from settings
       $startDate = explode('-', $params['eventfrom']);
       $startTime = explode(':', $params['eventfromtime']);
       $endDate = explode('-', $params['eventto']);
       $endTime = explode(':', $params['eventtotime']);
       
       // Load SabreDAV
       require_once(DOKU_PLUGIN.'davcal/vendor/autoload.php');
       $vcalendar = new \Sabre\VObject\Component\VCalendar();
       
       // Add VCalendar, UID and Event Name
       $event = $vcalendar->add('VEVENT');
       $uuid = \Sabre\VObject\UUIDUtil::getUUID();
       $event->add('UID', $uuid);
       $event->summary = $params['eventname'];
       
       // Add a description if requested
       $description = $params['eventdescription'];
       if($description !== '')
         $event->add('DESCRIPTION', $description);
       
       // Add attachments
       $attachments = $params['attachments'];
       if(!is_null($attachments))
         foreach($attachments as $attachment)
           $event->add('ATTACH', $attachment);
       
       // Create a timestamp for last modified, created and dtstamp values in UTC
       $dtStamp = new \DateTime(null, new \DateTimeZone('UTC'));
       $event->add('DTSTAMP', $dtStamp);
       $event->add('CREATED', $dtStamp);
       $event->add('LAST-MODIFIED', $dtStamp);
       
       // Adjust the start date, based on the given timezone information
       $dtStart = new \DateTime();
       $dtStart->setTimezone($timezone);            
       $dtStart->setDate(intval($startDate[0]), intval($startDate[1]), intval($startDate[2]));
       
       // Only add the time values if it's not an allday event
       if($params['allday'] != '1')
         $dtStart->setTime(intval($startTime[0]), intval($startTime[1]), 0);
       
       // Adjust the end date, based on the given timezone information
       $dtEnd = new \DateTime();
       $dtEnd->setTimezone($timezone);      
       $dtEnd->setDate(intval($endDate[0]), intval($endDate[1]), intval($endDate[2]));
       
       // Only add the time values if it's not an allday event
       if($params['allday'] != '1')
         $dtEnd->setTime(intval($endTime[0]), intval($endTime[1]), 0);
       
       // According to the VCal spec, we need to add a whole day here
       if($params['allday'] == '1')
           $dtEnd->add(new \DateInterval('P1D'));
       
       // Really add Start and End events
       $dtStartEv = $event->add('DTSTART', $dtStart);
       $dtEndEv = $event->add('DTEND', $dtEnd);
       
       // Adjust the DATE format for allday events
       if($params['allday'] == '1')
       {
           $dtStartEv['VALUE'] = 'DATE';
           $dtEndEv['VALUE'] = 'DATE';
       }
       
       $eventStr = $vcalendar->serialize();
       
       if(strpos($id, 'webdav://') === 0)
       {
           $wdc =& plugin_load('helper', 'webdavclient');
           if(is_null($wdc))
             return false;
           $connectionId = str_replace('webdav://', '', $id);
           return $wdc->addCalendarEntry($connectionId, $eventStr);
       }
       else 
       {
           // Actually add the values to the database
           $calid = $this->getCalendarIdForPage($id);
           $uri = uniqid('dokuwiki-').'.ics';
           $now = new \DateTime();
           
           $query = "INSERT INTO calendarobjects (calendarid, uri, calendardata, lastmodified, componenttype, firstoccurence, lastoccurence, size, etag, uid) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?)";
           $res = $this->sqlite->query($query, $calid, $uri, $eventStr, $now->getTimestamp(), 'VEVENT',
                                       $event->DTSTART->getDateTime()->getTimeStamp(), $event->DTEND->getDateTime()->getTimeStamp(),
                                       strlen($eventStr), md5($eventStr), $uuid);
           
           // If successfully, update the sync token database
           if($res !== false)
           {
               $this->updateSyncTokenLog($calid, $uri, 'added');
               return true;
           }
       }
       return false;
   }
 
   /**
    * Retrieve the calendar settings of a given calendar id
    * 
    * @param string $calid The calendar ID
    * 
    * @return array The calendar settings array
    */
   public function getCalendarSettings($calid)
   {
       $query = "SELECT id, principaluri, calendarcolor, displayname, uri, description, components, transparent, synctoken FROM calendars WHERE id= ? ";
       $res = $this->sqlite->query($query, $calid);
       $row = $this->sqlite->res2row($res);
       return $row;
   }
 
   /**
    * Retrieve all events that are within a given date range,
    * based on the timezone setting.
    * 
    * There is also support for retrieving recurring events,
    * using Sabre's VObject Iterator. Recurring events are represented
    * as individual calendar entries with the same UID.
    * 
    * @param string $id The page ID to work with
    * @param string $user The user ID to work with
    * @param string $startDate The start date as a string
    * @param string $endDate The end date as a string
    * @param string $color (optional) The calendar's color
    * 
    * @return array An array containing the calendar entries.
    */
   public function getEventsWithinDateRange($id, $user, $startDate, $endDate, $timezone, $color = null)
   {
       if($timezone !== '' && $timezone !== 'local')
           $timezone = new \DateTimeZone($timezone);
       else
           $timezone = new \DateTimeZone('UTC');
       $data = array();
       
       $query = "SELECT calendardata, componenttype, uid FROM calendarobjects WHERE calendarid = ?";
       $startTs = null;
       $endTs = null;
       if($startDate !== null)
       {
         $startTs = new \DateTime($startDate);
         $query .= " AND lastoccurence > ".$this->sqlite->quote_string($startTs->getTimestamp());
       }
       if($endDate !== null)
       {
         $endTs = new \DateTime($endDate);
         $query .= " AND firstoccurence < ".$this->sqlite->quote_string($endTs->getTimestamp());
       }
       
       // Load SabreDAV
       require_once(DOKU_PLUGIN.'davcal/vendor/autoload.php');
       
       if(strpos($id, 'webdav://') === 0)
       {
           $wdc =& plugin_load('helper', 'webdavclient');
           if(is_null($wdc))
             return $data;
           $connectionId = str_replace('webdav://', '', $id);
           $arr = $wdc->getCalendarEntries($connectionId, $startDate, $endDate);
       }
       else
       {
           $calid = $this->getCalendarIdForPage($id);
           if(is_null($color))
             $color = $this->getCalendarColorForCalendar($calid);
     
           // Retrieve matching calendar objects
           $res = $this->sqlite->query($query, $calid);
           $arr = $this->sqlite->res2arr($res);
       }
       
       // Parse individual calendar entries
       foreach($arr as $row)
       {
           if(isset($row['calendardata']))
           {
               $entry = array();
               $vcal = \Sabre\VObject\Reader::read($row['calendardata']);
               $recurrence = $vcal->VEVENT->RRULE;
               // If it is a recurring event, pass it through Sabre's EventIterator
               if($recurrence != null)
               {
                   $rEvents = new \Sabre\VObject\Recur\EventIterator(array($vcal->VEVENT));
                   $rEvents->rewind();
                   while($rEvents->valid())
                   {
                       $event = $rEvents->getEventObject();
                       // If we are after the given time range, exit
                       if(($endTs !== null) && ($rEvents->getDtStart()->getTimestamp() > $endTs->getTimestamp()))
                           break;
                         
                       // If we are before the given time range, continue
                       if(($startTs != null) && ($rEvents->getDtEnd()->getTimestamp() < $startTs->getTimestamp()))
                       {
                           $rEvents->next();
                           continue;
                       }
                       
                       // If we are within the given time range, parse the event
                       $data[] = $this->convertIcalDataToEntry($event, $id, $timezone, $row['uid'], $color, true);
                       $rEvents->next();
                   }
               }
               else
                 $data[] = $this->convertIcalDataToEntry($vcal->VEVENT, $id, $timezone, $row['uid'], $color);
           }
       }
       return $data;
   }
 
   /**
    * Helper function that parses the iCal data of a VEVENT to a calendar entry.
    * 
    * @param \Sabre\VObject\VEvent $event The event to parse
    * @param \DateTimeZone $timezone The timezone object
    * @param string $uid The entry's UID
    * @param boolean $recurring (optional) Set to true to define a recurring event
    * 
    * @return array The parse calendar entry
    */
   private function convertIcalDataToEntry($event, $page, $timezone, $uid, $color, $recurring = false)
   {
       $entry = array();
       $start = $event->DTSTART;
       // Parse only if the start date/time is present
       if($start !== null)
       {
         $dtStart = $start->getDateTime();
         $dtStart->setTimezone($timezone);
         
         // moment.js doesn't like times be given even if 
         // allDay is set to true
         // This should fix T23
         if($start['VALUE'] == 'DATE')
         {
           $entry['allDay'] = true;
           $entry['start'] = $dtStart->format("Y-m-d");
         }
         else
         {
           $entry['allDay'] = false;
           $entry['start'] = $dtStart->format(\DateTime::ATOM);
         }
       }
       $end = $event->DTEND;
       // Parse only if the end date/time is present
       if($end !== null)
       {
         $dtEnd = $end->getDateTime();
         $dtEnd->setTimezone($timezone);
         if($end['VALUE'] == 'DATE')
           $entry['end'] = $dtEnd->format("Y-m-d");
         else 
           $entry['end'] = $dtEnd->format(\DateTime::ATOM);
       }
       $description = $event->DESCRIPTION;
       if($description !== null)
         $entry['description'] = (string)$description;
       else
         $entry['description'] = '';
       $attachments = $event->ATTACH;
       if($attachments !== null)
       {
         $entry['attachments'] = array();
         foreach($attachments as $attachment)
           $entry['attachments'][] = (string)$attachment;
       }
       $entry['title'] = (string)$event->summary;
       $entry['id'] = $uid;
       $entry['page'] = $page;
       $entry['color'] = $color;
       $entry['recurring'] = $recurring;
       
       return $entry;
   }
   
   /**
    * Retrieve an event by its UID
    * 
    * @param string $uid The event's UID
    * 
    * @return mixed The table row with the given event
    */
   public function getEventWithUid($uid)
   {
       $query = "SELECT calendardata, calendarid, componenttype, uri FROM calendarobjects WHERE uid = ?";
       $res = $this->sqlite->query($query, $uid);
       $row = $this->sqlite->res2row($res);
       return $row;
   }
   
   /**
    * Retrieve information of a calendar's object, not including the actual
    * calendar data! This is mainly neede for the sync support.
    * 
    * @param int $calid The calendar ID
    * 
    * @return mixed The result
    */
   public function getCalendarObjects($calid)
   {
       $query = "SELECT id, uri, lastmodified, etag, calendarid, size, componenttype FROM calendarobjects WHERE calendarid = ?";
       $res = $this->sqlite->query($query, $calid);
       $arr = $this->sqlite->res2arr($res);
       return $arr; 
   }
   
   /**
    * Retrieve a single calendar object by calendar ID and URI
    * 
    * @param int $calid The calendar's ID
    * @param string $uri The object's URI
    * 
    * @return mixed The result
    */
   public function getCalendarObjectByUri($calid, $uri)
   {
       $query = "SELECT id, uri, lastmodified, etag, calendarid, size, calendardata, componenttype FROM calendarobjects WHERE calendarid = ? AND uri = ?";
       $res = $this->sqlite->query($query, $calid, $uri);
       $row = $this->sqlite->res2row($res);
       return $row;
   }
   
   /**
    * Retrieve several calendar objects by specifying an array of URIs.
    * This is mainly neede for sync.
    * 
    * @param int $calid The calendar's ID
    * @param array $uris An array of URIs
    * 
    * @return mixed The result
    */
   public function getMultipleCalendarObjectsByUri($calid, $uris)
   {
         $query = "SELECT id, uri, lastmodified, etag, calendarid, size, calendardata, componenttype FROM calendarobjects WHERE calendarid = ? AND uri IN (";
         // Inserting a whole bunch of question marks
         $query .= implode(',', array_fill(0, count($uris), '?'));
         $query .= ')';
         $vals = array_merge(array($calid), $uris);
         
         $res = $this->sqlite->query($query, $vals);
         $arr = $this->sqlite->res2arr($res);
         return $arr;
   }
   
   /**
    * Retrieve all calendar events for a given calendar ID
    * 
    * @param string $calid The calendar's ID
    * 
    * @return array An array containing all calendar data
    */
   public function getAllCalendarEvents($calid)
   {
       $query = "SELECT calendardata, uid, componenttype, uri FROM calendarobjects WHERE calendarid = ?";
       $res = $this->sqlite->query($query, $calid);
       $arr = $this->sqlite->res2arr($res);
       return $arr;
   }
   
   /**
    * Edit a calendar entry for a page, given by its parameters.
    * The params array has the same format as @see addCalendarEntryForPage
    * 
    * @param string $id The page's ID to work on
    * @param string $user The user's ID to work on
    * @param array $params The parameter array for the edited calendar event
    * 
    * @return boolean True on success, otherwise false
    */
   public function editCalendarEntryForPage($id, $user, $params)
   {
       if($params['currenttz'] !== '' && $params['currenttz'] !== 'local')
           $timezone = new \DateTimeZone($params['currenttz']);
       elseif($params['currenttz'] === 'local')
           $timezone = new \DateTimeZone($params['detectedtz']);
       else
           $timezone = new \DateTimeZone('UTC');
           
       // Parse dates
       $startDate = explode('-', $params['eventfrom']);
       $startTime = explode(':', $params['eventfromtime']);
       $endDate = explode('-', $params['eventto']);
       $endTime = explode(':', $params['eventtotime']);
       
       // Retrieve the existing event based on the UID
       $uid = $params['uid'];
       
       if(strpos($id, 'webdav://') === 0)
       {
         $wdc =& plugin_load('helper', 'webdavclient');
         if(is_null($wdc))
           return false;
         $event = $wdc->getCalendarEntryByUid($uid);
       }
       else
       {
         $event = $this->getEventWithUid($uid);
       }
       
       // Load SabreDAV
       require_once(DOKU_PLUGIN.'davcal/vendor/autoload.php');
       if(!isset($event['calendardata']))
         return false;
       $uri = $event['uri'];
       $calid = $event['calendarid'];
       
       // Parse the existing event
       $vcal = \Sabre\VObject\Reader::read($event['calendardata']);
       $vevent = $vcal->VEVENT;
       
       // Set the new event values
       $vevent->summary = $params['eventname'];
       $dtStamp = new \DateTime(null, new \DateTimeZone('UTC'));
       $description = $params['eventdescription'];
       
       // Remove existing timestamps to overwrite them
       $vevent->remove('DESCRIPTION');      
       $vevent->remove('DTSTAMP');
       $vevent->remove('LAST-MODIFIED');
       $vevent->remove('ATTACH');
       
       // Add new time stamps and description
       $vevent->add('DTSTAMP', $dtStamp);
       $vevent->add('LAST-MODIFIED', $dtStamp);
       if($description !== '')
         $vevent->add('DESCRIPTION', $description);
 
       // Add attachments
       $attachments = $params['attachments'];
       if(!is_null($attachments))
         foreach($attachments as $attachment)
           $vevent->add('ATTACH', $attachment);
       
       // Setup DTSTART      
       $dtStart = new \DateTime();
       $dtStart->setTimezone($timezone);      
       $dtStart->setDate(intval($startDate[0]), intval($startDate[1]), intval($startDate[2]));
       if($params['allday'] != '1')
         $dtStart->setTime(intval($startTime[0]), intval($startTime[1]), 0);
       
       // Setup DTEND
       $dtEnd = new \DateTime();
       $dtEnd->setTimezone($timezone);      
       $dtEnd->setDate(intval($endDate[0]), intval($endDate[1]), intval($endDate[2]));
       if($params['allday'] != '1')
         $dtEnd->setTime(intval($endTime[0]), intval($endTime[1]), 0);
       
       // According to the VCal spec, we need to add a whole day here
       if($params['allday'] == '1')
           $dtEnd->add(new \DateInterval('P1D'));
       $vevent->remove('DTSTART');
       $vevent->remove('DTEND');
       $dtStartEv = $vevent->add('DTSTART', $dtStart);
       $dtEndEv = $vevent->add('DTEND', $dtEnd);
       
       // Remove the time for allday events
       if($params['allday'] == '1')
       {
           $dtStartEv['VALUE'] = 'DATE';
           $dtEndEv['VALUE'] = 'DATE';
       }
       $eventStr = $vcal->serialize();
       if(strpos($id, 'webdav://') === 0)
       {
           $connectionId = str_replace('webdav://', '', $id);
           return $wdc->editCalendarEntry($connectionId, $uid, $eventStr);
       }
       else
       {
           $now = new DateTime();
           // Actually write to the database
           $query = "UPDATE calendarobjects SET calendardata = ?, lastmodified = ?, ".
                    "firstoccurence = ?, lastoccurence = ?, size = ?, etag = ? WHERE uid = ?";
           $res = $this->sqlite->query($query, $eventStr, $now->getTimestamp(), $dtStart->getTimestamp(),
                                       $dtEnd->getTimestamp(), strlen($eventStr), md5($eventStr), $uid);
           if($res !== false)
           {
               $this->updateSyncTokenLog($calid, $uri, 'modified');
               return true;
           }
       }
       return false;
   }
 
   /**
    * Delete an event from a calendar by calendar ID and URI
    * 
    * @param int $calid The calendar's ID
    * @param string $uri The object's URI
    * 
    * @return true
    */
   public function deleteCalendarEntryForCalendarByUri($calid, $uri)
   {
       $query = "DELETE FROM calendarobjects WHERE calendarid = ? AND uri = ?";
       $res = $this->sqlite->query($query, $calid, $uri);
       if($res !== false)
       {
           $this->updateSyncTokenLog($calid, $uri, 'deleted');
       }
       return true;      
   }
 
   /**
    * Delete a calendar entry for a given page. Actually, the event is removed
    * based on the entry's UID, so that page ID is no used.
    * 
    * @param string $id The page's ID (unused)
    * @param array $params The parameter array to work with
    * 
    * @return boolean True
    */
   public function deleteCalendarEntryForPage($id, $params)
   {
       $uid = $params['uid'];
       if(strpos($id, 'webdav://') === 0)
       {
         $wdc =& plugin_load('helper', 'webdavclient');
         if(is_null($wdc))
           return false;
         $connectionId = str_replace('webdav://', '', $id);
         $result = $wdc->deleteCalendarEntry($connectionId, $uid);
         return $result;
       }
       $event = $this->getEventWithUid($uid);
       $calid = $event['calendarid'];
       $uri = $event['uri'];
       $query = "DELETE FROM calendarobjects WHERE uid = ?";
       $res = $this->sqlite->query($query, $uid);
       if($res !== false)
       {
           $this->updateSyncTokenLog($calid, $uri, 'deleted');
       }
       return true;
   }
   
   /**
    * Retrieve the current sync token for a calendar
    * 
    * @param string $calid The calendar id
    * 
    * @return mixed The synctoken or false
    */
   public function getSyncTokenForCalendar($calid)
   {
       $row = $this->getCalendarSettings($calid);
       if(isset($row['synctoken']))
           return $row['synctoken'];
       return false;
   }
   
   /**
    * Helper function to convert the operation name to 
    * an operation code as stored in the database
    * 
    * @param string $operationName The operation name
    * 
    * @return mixed The operation code or false
    */
   public function operationNameToOperation($operationName)
   {
       switch($operationName)
       {
           case 'added':
               return 1;
           break;
           case 'modified':
               return 2;
           break;
           case 'deleted':
               return 3;
           break;
       }
       return false;
   }
   
   /**
    * Update the sync token log based on the calendar id and the 
    * operation that was performed.
    * 
    * @param string $calid The calendar ID that was modified
    * @param string $uri The calendar URI that was modified
    * @param string $operation The operation that was performed
    * 
    * @return boolean True on success, otherwise false
    */
   private function updateSyncTokenLog($calid, $uri, $operation)
   {
       $currentToken = $this->getSyncTokenForCalendar($calid);
       $operationCode = $this->operationNameToOperation($operation);
       if(($operationCode === false) || ($currentToken === false))
           return false;
       $values = array($uri,
                       $currentToken,
                       $calid,
                       $operationCode
       );
       $query = "INSERT INTO calendarchanges (uri, synctoken, calendarid, operation) VALUES(?, ?, ?, ?)";
       $res = $this->sqlite->query($query, $uri, $currentToken, $calid, $operationCode);
       if($res === false)
         return false;
       $currentToken++;
       $query = "UPDATE calendars SET synctoken = ? WHERE id = ?";
       $res = $this->sqlite->query($query, $currentToken, $calid);
       return ($res !== false);
   }
   
   /**
    * Return the sync URL for a given Page, i.e. a calendar
    * 
    * @param string $id The page's ID
    * @param string $user (optional) The user's ID
    * 
    * @return mixed The sync url or false
    */
   public function getSyncUrlForPage($id, $user = null)
   {
       if(is_null($userid))
       {
         if(isset($_SERVER['REMOTE_USER']) && !is_null($_SERVER['REMOTE_USER']))
         {
           $userid = $_SERVER['REMOTE_USER'];
         }
         else
         {
           return false;
         }
       }
       
       $calid = $this->getCalendarIdForPage($id);
       if($calid === false)
         return false;
       
       $calsettings = $this->getCalendarSettings($calid);
       if(!isset($calsettings['uri']))
         return false;
       
       $syncurl = DOKU_URL.'lib/plugins/davcal/calendarserver.php/calendars/'.$user.'/'.$calsettings['uri'];
       return $syncurl; 
   }
   
   /**
    * Return the private calendar's URL for a given page
    * 
    * @param string $id the page ID
    * 
    * @return mixed The private URL or false
    */
   public function getPrivateURLForPage($id)
   {
       $calid = $this->getCalendarIdForPage($id);
       if($calid === false)
         return false;
       
       return $this->getPrivateURLForCalendar($calid);
   }
   
   /**
    * Return the private calendar's URL for a given calendar ID
    * 
    * @param string $calid The calendar's ID
    * 
    * @return mixed The private URL or false
    */
   public function getPrivateURLForCalendar($calid)
   {
       if(isset($this->cachedValues['privateurl'][$calid]))
         return $this->cachedValues['privateurl'][$calid];
       $query = "SELECT url FROM calendartoprivateurlmapping WHERE calid = ?";
       $res = $this->sqlite->query($query, $calid);
       $row = $this->sqlite->res2row($res);
       if(!isset($row['url']))
       {
           $url = uniqid("dokuwiki-").".ics";
           $query = "INSERT INTO calendartoprivateurlmapping (url, calid) VALUES(?, ?)";
           $res = $this->sqlite->query($query, $url, $calid);
           if($res === false)
             return false;
       }
       else
       {
           $url = $row['url'];
       }
       
       $url = DOKU_URL.'lib/plugins/davcal/ics.php/'.$url;
       $this->cachedValues['privateurl'][$calid] = $url;
       return $url;
   }
   
   /**
    * Retrieve the calendar ID for a given private calendar URL
    * 
    * @param string $url The private URL
    * 
    * @return mixed The calendar ID or false
    */
   public function getCalendarForPrivateURL($url)
   {
       $query = "SELECT calid FROM calendartoprivateurlmapping WHERE url = ?";
       $res = $this->sqlite->query($query, $url);
       $row = $this->sqlite->res2row($res);
       if(!isset($row['calid']))
         return false;
       return $row['calid'];
   }
   
   /**
    * Return a given calendar as ICS feed, i.e. all events in one ICS file.
    * 
    * @param string $calid The calendar ID to retrieve
    * 
    * @return mixed The calendar events as string or false
    */
   public function getCalendarAsICSFeed($calid)
   {
       $calSettings = $this->getCalendarSettings($calid);
       if($calSettings === false)
         return false;
       $events = $this->getAllCalendarEvents($calid);
       if($events === false)
         return false;
       
       // Load SabreDAV
       require_once(DOKU_PLUGIN.'davcal/vendor/autoload.php');      
       $out = "BEGIN:VCALENDAR\r\nVERSION:2.0\r\nPRODID:-//DAVCal//DAVCal for DokuWiki//EN\r\nCALSCALE:GREGORIAN\r\nX-WR-CALNAME:";
       $out .= $calSettings['displayname']."\r\n";
       foreach($events as $event)
       {
           $vcal = \Sabre\VObject\Reader::read($event['calendardata']);
           $evt = $vcal->VEVENT;
           $out .= $evt->serialize();
       }
       $out .= "END:VCALENDAR\r\n";
       return $out;
   }
   
   /**
    * Retrieve a configuration option for the plugin
    * 
    * @param string $key The key to query
    * @return mixed The option set, null if not found
    */
   public function getConfig($key)
   {
       return $this->getConf($key);
   }
   
   /**
    * Parses some information from calendar objects, used for optimized
    * calendar-queries. Taken nearly unmodified from Sabre's PDO backend
    *
    * Returns an array with the following keys:
    *   * etag - An md5 checksum of the object without the quotes.
    *   * size - Size of the object in bytes
    *   * componentType - VEVENT, VTODO or VJOURNAL
    *   * firstOccurence
    *   * lastOccurence
    *   * uid - value of the UID property
    *
    * @param string $calendarData
    * @return array
    */
   protected function getDenormalizedData($calendarData) 
   {
     require_once(DOKU_PLUGIN.'davcal/vendor/autoload.php');
     
     $vObject = \Sabre\VObject\Reader::read($calendarData);
     $componentType = null;
     $component = null;
     $firstOccurence = null;
     $lastOccurence = null;
     $uid = null;
     foreach ($vObject->getComponents() as $component) 
     {
         if ($component->name !== 'VTIMEZONE') 
         {
             $componentType = $component->name;
             $uid = (string)$component->UID;
             break;
         }
     }
     if (!$componentType) 
     {
         return false;
     }
     if ($componentType === 'VEVENT') 
     {
         $firstOccurence = $component->DTSTART->getDateTime()->getTimeStamp();
         // Finding the last occurence is a bit harder
         if (!isset($component->RRULE)) 
         {
             if (isset($component->DTEND)) 
             {
                 $lastOccurence = $component->DTEND->getDateTime()->getTimeStamp();
             }
             elseif (isset($component->DURATION)) 
             {
                 $endDate = clone $component->DTSTART->getDateTime();
                 $endDate->add(\Sabre\VObject\DateTimeParser::parse($component->DURATION->getValue()));
                 $lastOccurence = $endDate->getTimeStamp();
             } 
             elseif (!$component->DTSTART->hasTime()) 
             {
                 $endDate = clone $component->DTSTART->getDateTime();
                 $endDate->modify('+1 day');
                 $lastOccurence = $endDate->getTimeStamp();
             } 
             else 
             {
                 $lastOccurence = $firstOccurence;
             }
         } 
         else 
         {
             $it = new \Sabre\VObject\Recur\EventIterator($vObject, (string)$component->UID);
             $maxDate = new \DateTime('2038-01-01');
             if ($it->isInfinite()) 
             {
                 $lastOccurence = $maxDate->getTimeStamp();
             } 
             else 
             {
                 $end = $it->getDtEnd();
                 while ($it->valid() && $end < $maxDate) 
                 {
                     $end = $it->getDtEnd();
                     $it->next();
                 }
                 $lastOccurence = $end->getTimeStamp();
             }
         }
     }
 
     return array(
         'etag'           => md5($calendarData),
         'size'           => strlen($calendarData),
         'componentType'  => $componentType,
         'firstOccurence' => $firstOccurence,
         'lastOccurence'  => $lastOccurence,
         'uid'            => $uid,
     );
 
   }
 
   /**
    * Query a calendar by ID and taking several filters into account.
    * This is heavily based on Sabre's PDO backend.
    * 
    * @param int $calendarId The calendar's ID
    * @param array $filters The filter array to apply
    * 
    * @return mixed The result
    */
   public function calendarQuery($calendarId, $filters)
   {
     $componentType = null;
     $requirePostFilter = true;
     $timeRange = null;
 
     // if no filters were specified, we don't need to filter after a query
     if (!$filters['prop-filters'] && !$filters['comp-filters']) 
     {
         $requirePostFilter = false;
     }
 
     // Figuring out if there's a component filter
     if (count($filters['comp-filters']) > 0 && !$filters['comp-filters'][0]['is-not-defined']) 
     {
         $componentType = $filters['comp-filters'][0]['name'];
 
         // Checking if we need post-filters
         if (!$filters['prop-filters'] && !$filters['comp-filters'][0]['comp-filters'] && !$filters['comp-filters'][0]['time-range'] && !$filters['comp-filters'][0]['prop-filters']) 
         {
             $requirePostFilter = false;
         }
         // There was a time-range filter
         if ($componentType == 'VEVENT' && isset($filters['comp-filters'][0]['time-range'])) 
         {
             $timeRange = $filters['comp-filters'][0]['time-range'];
 
             // If start time OR the end time is not specified, we can do a
             // 100% accurate mysql query.
             if (!$filters['prop-filters'] && !$filters['comp-filters'][0]['comp-filters'] && !$filters['comp-filters'][0]['prop-filters'] && (!$timeRange['start'] || !$timeRange['end'])) 
             {
                 $requirePostFilter = false;
             }
         }
 
     }
 
     if ($requirePostFilter) 
     {
         $query = "SELECT uri, calendardata FROM calendarobjects WHERE calendarid = ?";
     } 
     else 
     {
         $query = "SELECT uri FROM calendarobjects WHERE calendarid = ?";
     }
 
     $values = array(
         $calendarId
     );
 
     if ($componentType) 
     {
         $query .= " AND componenttype = ?";
         $values[] = $componentType;
     }
 
     if ($timeRange && $timeRange['start']) 
     {
         $query .= " AND lastoccurence > ?";
         $values[] = $timeRange['start']->getTimeStamp();
     }
     if ($timeRange && $timeRange['end']) 
     {
         $query .= " AND firstoccurence < ?";
         $values[] = $timeRange['end']->getTimeStamp();
     }
 
     $res = $this->sqlite->query($query, $values);
     $arr = $this->sqlite->res2arr($res);
 
     $result = array();
     foreach($arr as $row)
     {
         if ($requirePostFilter) 
         {
             if (!$this->validateFilterForObject($row, $filters))
             {
                 continue;
             }
         }
         $result[] = $row['uri'];
 
     }
 
     return $result;
   }
   
   /**
    * This method validates if a filter (as passed to calendarQuery) matches
    * the given object. Taken from Sabre's PDO backend
    *
    * @param array $object
    * @param array $filters
    * @return bool
    */
   protected function validateFilterForObject($object, $filters) 
   {
       require_once(DOKU_PLUGIN.'davcal/vendor/autoload.php');
       // Unfortunately, setting the 'calendardata' here is optional. If
       // it was excluded, we actually need another call to get this as
       // well.
       if (!isset($object['calendardata'])) 
       {
           $object = $this->getCalendarObjectByUri($object['calendarid'], $object['uri']);
       }
       
       $vObject = \Sabre\VObject\Reader::read($object['calendardata']);
       $validator = new \Sabre\CalDAV\CalendarQueryValidator();
       
       return $validator->validate($vObject, $filters);
 
   }
   
   /**
    * Retrieve changes for a given calendar based on the given syncToken.
    * 
    * @param int $calid The calendar's ID
    * @param int $syncToken The supplied sync token
    * @param int $syncLevel The sync level
    * @param int $limit The limit of changes
    * 
    * @return array The result
    */
   public function getChangesForCalendar($calid, $syncToken, $syncLevel, $limit = null)
   {
       // Current synctoken
       $currentToken = $this->getSyncTokenForCalendar($calid);
 
       if ($currentToken === false) return null;
 
       $result = array(
           'syncToken' => $currentToken,
           'added'     => array(),
           'modified'  => array(),
           'deleted'   => array(),
       );
 
       if ($syncToken) 
       {
 
           $query = "SELECT uri, operation FROM calendarchanges WHERE synctoken >= ? AND synctoken < ? AND calendarid = ? ORDER BY synctoken";
           if ($limit > 0) $query .= " LIMIT " . (int)$limit;
 
           // Fetching all changes
           $res = $this->sqlite->query($query, $syncToken, $currentToken, $calid);
           if($res === false)
               return null;
 
           $arr = $this->sqlite->res2arr($res);
           $changes = array();
 
           // This loop ensures that any duplicates are overwritten, only the
           // last change on a node is relevant.
           foreach($arr as $row) 
           {
               $changes[$row['uri']] = $row['operation'];
           }
 
           foreach ($changes as $uri => $operation) 
           {
               switch ($operation) 
               {
                   case 1 :
                       $result['added'][] = $uri;
                       break;
                   case 2 :
                       $result['modified'][] = $uri;
                       break;
                   case 3 :
                       $result['deleted'][] = $uri;
                       break;
               }
 
           }
       }
       else 
       {
           // No synctoken supplied, this is the initial sync.
           $query = "SELECT uri FROM calendarobjects WHERE calendarid = ?";
           $res = $this->sqlite->query($query);
           $arr = $this->sqlite->res2arr($res);
 
           $result['added'] = $arr;
       }
       return $result;
   }
 
 }
diff --git a/plugin.info.txt b/plugin.info.txt
--- a/plugin.info.txt
+++ b/plugin.info.txt
@@ -1,7 +1,7 @@
 base	davcal
 author  Andreas Boehler
 email   dev@aboehler.at
-date    2016-07-02
+date    2016-07-05
 name    Calendar PlugIn with CalDAV sharing support
 desc    Create one calendar per page and share/subscribe via CalDAV
 url     http://www.dokuwiki.org/plugin:davcal
diff --git a/script.js b/script.js
--- a/script.js
+++ b/script.js
@@ -1,845 +1,850 @@
 /* DOKUWIKI:include_once fullcalendar-2.4.0/moment.js */
 /* DOKUWIKI:include_once fullcalendar-2.4.0/fullcalendar.js */
 /* DOKUWIKI:include_once fullcalendar-2.4.0/lang/de.js */
 /* DOKUWIKI:include_once fullcalendar-2.4.0/lang/en.js */
 /* DOKUWIKI:include_once fullcalendar-2.4.0/lang/fr.js */
 /* DOKUWIKI:include_once fullcalendar-2.4.0/lang/nl.js */
 /* DOKUWIKI:include_once datetimepicker-2.4.5/jquery.datetimepicker.js */
 /* DOKUWIKI:include_once jstz.js */
 
 /**
  * Initialize the DAVCal script, attaching some event handlers and triggering
  * the initial load of the fullcalendar JS
  */
 jQuery(function() {
     // Redefine functions for using moment.js with datetimepicker
     
     Date.parseDate = function( input, format ){
       return moment(input,format).toDate();
     };
     Date.prototype.dateFormat = function( format ){
       return moment(this).format(format);
     };
     
     // Attach to event links
     var calendarpage = jQuery('#fullCalendar').data('calendarpage');
     if(!calendarpage) return;
     dw_davcal__modals.page = calendarpage;
     
     jQuery('div.fullCalendarSettings a').each(function() {
         var $link = jQuery(this);
         var href = $link.attr('href');
         if (!href) return;
 
         $link.click(
             function(e) {
                 dw_davcal__modals.showSettingsDialog();
                 e.preventDefault();
                 return '';
             }
         );
         }
     );
     
     // First, retrieve the current settings.
     // Upon success, initialize fullcalendar.
     var postArray = { };
     jQuery.post(
         DOKU_BASE + 'lib/exe/ajax.php',
         {
             call: 'plugin_davcal',
             id: dw_davcal__modals.page,
             page: dw_davcal__modals.page,
             action: 'getSettings',
             params: postArray,
             sectok: JSINFO.plugin.davcal['sectok']
         },
         function(data)
         {
             var result = data['result'];
             if(result === true)
             {
                 dw_davcal__modals.settings = data['settings'];
                 var tz = false;
                 if(data['settings']['timezone'] !== '')
                     tz = data['settings']['timezone'];
                 // Force-overwrite thhe timezone setting if requested
                 if(data['settings']['meta']['forcetimezone'] !== 'no')
                     tz = data['settings']['meta']['forcetimezone'];
                 var fcOptions = {
                     dayClick: function(date, jsEvent, view) {
                         dw_davcal__modals.showEditEventDialog(date, false);
                     },
                     eventClick: function(calEvent, jsEvent, view) {
                         dw_davcal__modals.showEditEventDialog(calEvent, true);
                     },
                     events: {
                         url: DOKU_BASE + 'lib/exe/ajax.php',
                         type: 'POST',
                         data: {
                             call: 'plugin_davcal',
                             action: 'getEvents',
                             id: dw_davcal__modals.page,
                             page: dw_davcal__modals.page,
                             sectok: JSINFO.plugin.davcal['sectok']
                         },
                         error: function() {
                             dw_davcal__modals.msg = LANG.plugins.davcal['error_retrieving_data'];
                             dw_davcal__modals.showDialog(false);
                         }
                     },
                     header: {
                         left: 'title',
                         center: 'today prev,next',
                         right: 'month,agendaWeek,agendaDay'
                     },
                     lang: JSINFO.plugin.davcal['language'],
                     weekNumbers: (data['settings']['weeknumbers'] == 1) ? true : false,
                     timezone: tz,
                     weekends: (data['settings']['workweek'] == 1) ? false : true,
                     firstDay: (data['settings']['monday'] == 1) ? 1 : 0,
                     defaultView: data['settings']['meta']['view']
                 };
                 var timeformat = data['settings']['timeformat'];
                 // Force-overwrite the user's timezone setting if requested by the calendar
                 if(data['settings']['meta']['forcetimeformat'] !== 'no')
                     timeformat = data['settings']['meta']['forcetimeformat'];
                 if(timeformat !== 'lang')
                 {
                     // If the time format is language-based, we don't need to pass
                     // the timeFormat option to fullCalendar
                     if(timeformat == '24h')
                     {
                         fcOptions.timeFormat = 'H:mm';
                     }
                     if(timeformat == '12h')
                     {
                         fcOptions.timeFormat = 'h:mmt';
                     }
                 }
                 var detectedTz = jstz.determine().name();
                 dw_davcal__modals.detectedTz = detectedTz;
                 // The current TZ value holds either the uers's selection or
                 // the force timezone value
                 dw_davcal__modals.currentTz = (tz === false) ? '' : tz;
                 // Initialize the davcal popup
                 var res = jQuery('#fullCalendar').fullCalendar(fcOptions);
             }
         }
     );    
 });
 
 /**
  * This holds all modal windows that DAVCal uses.
  */
 var dw_davcal__modals = {
     $editEventDialog: null,
     $dialog: null,
     $settingsDialog: null,
     $inputDialog: null,
     msg: null,
     completeCb: null,
     action: null,
     uid: null,
     settings: null,
     page: null,
     detectedTz: null,
     currentTz: null,
     
     /**
      * Show the settings dialog
      */
     // FIXME: Hide URLs for multi-calendar
     showSettingsDialog : function() {
         if(dw_davcal__modals.$settingsDialog)
             return;
 
         // Dialog buttons are language-dependent and defined here.
         // Attach event handlers for save and cancel.
         var dialogButtons = {};
         if(!JSINFO.plugin.davcal['disable_settings'])
         {
             dialogButtons[LANG.plugins.davcal['save']] = function() {
                 var postArray = { };
                 jQuery("input[class=dw_davcal__settings], select[class=dw_davcal__settings]").each(function() {
                   if(jQuery(this).attr('type') == 'checkbox')
                   {
                       postArray[jQuery(this).prop('name')] = jQuery(this).prop('checked') ? 1 : 0;
                   }
                   else
                   {
                       postArray[jQuery(this).prop('name')] = jQuery(this).val();
                   }
                 });
                 jQuery('#dw_davcal__ajaxsettings').html('<img src="'+DOKU_BASE+'lib/images/throbber.gif" alt="" width="16" height="16" />');
                 jQuery.post(
                     DOKU_BASE + 'lib/exe/ajax.php',
                     {
                         call: 'plugin_davcal',
                         id: dw_davcal__modals.page,
                         page: dw_davcal__modals.page,
                         action: 'saveSettings',
                         params: postArray,
                         sectok: JSINFO.plugin.davcal['sectok']
                     },
                     function(data)
                     {
                         var result = data['result'];
                         var html = data['html'];
                         jQuery('#dw_davcal__ajaxsettings').html(html);
                         if(result === true)
                         {
                             location.reload();
                         }
                     }
                 );
             };
         }
         dialogButtons[LANG.plugins.davcal['cancel']] = function () {
             dw_davcal__modals.hideSettingsDialog();
         };
         
         var settingsHtml = '<div><table>';
         
         if(JSINFO.plugin.davcal['disable_settings'] && JSINFO.plugin.davcal['disable_sync'] && JSINFO.plugin.davcal['disable_ics'])
         {
             settingsHtml += LANG.plugins.davcal['nothing_to_show'];
         }
         
         if(!JSINFO.plugin.davcal['disable_settings'])
         {
             settingsHtml += '<tr><td>' + LANG.plugins.davcal['timezone'] + '</td><td><select name="timezone" id="dw_davcal__settings_timezone" class="dw_davcal__settings"></select></td></tr>' +
             '<tr><td>' + LANG.plugins.davcal['timeformat'] + '</td><td><select name="timeformat" id="dw_davcal__settings_timeformat" class="dw_davcal__settings"></select></td></tr>' +
             '<tr><td>' + LANG.plugins.davcal['weeknumbers'] + '</td><td><input type="checkbox" name="weeknumbers" id="dw_davcal__settings_weeknumbers" class="dw_davcal__settings"></td></tr>' +
             '<tr><td>' + LANG.plugins.davcal['only_workweek'] + '</td><td><input type="checkbox" name="workweek" id="dw_davcal__settings_workweek" class="dw_davcal__settings"></td></tr>' +
             '<tr><td>' + LANG.plugins.davcal['start_monday'] + '</td><td><input type="checkbox" name="monday" id="dw_davcal__settings_monday" class="dw_davcal__settings"></td></tr>';
          }
          
          if(!JSINFO.plugin.davcal['disable_sync'])
          {
              settingsHtml += '<tr id="dw_davcal__settings_syncurl"><td>' + LANG.plugins.davcal['sync_url'] + '</td><td><input type="text" name="syncurl" readonly="readonly" id="dw_davcal__settings_syncurl_edit" class="dw_davcal__text" value="' + dw_davcal__modals.settings['syncurl'] + '"></td></tr>';
              settingsHtml += '<tr id="dw_davcal__settings_principalurl"><td>' + LANG.plugins.davcal['sync_ical'] + '</td><td><input type="text" name="principalurl" readonly="readonly" id="dw_davcal__settings_principalurl_edit" class="dw_davcal__text" value="' + dw_davcal__modals.settings['principalurl'] + '"></td></tr>';
          }
          
          if(!JSINFO.plugin.davcal['disable_ics'])
          {
              settingsHtml += '<tr id="dw_davcal__settings_privateurl"><td>' + LANG.plugins.davcal['private_url'] + '</td><td><input type="text" name="privateurl" readonly="readonly" id="dw_davcal__settings_privateurl_edit" class="dw_davcal__text" value="' + dw_davcal__modals.settings['privateurl'] + '"></td></tr>';
          }
          
          settingsHtml += '</table>' +
             '</div>' +
             '<div id="dw_davcal__ajaxsettings"></div>';
         
         dw_davcal__modals.$settingsDialog = jQuery(document.createElement('div'))
        .dialog({
            autoOpen: false,
            draggable: true,
            // fix for dragging: http://stackoverflow.com/questions/17247486/jquery-ui-dialog-dragging-issues
            drag: function(event, ui) {
                var fixPix = jQuery(document).scrollTop();
                iObj = ui.position;
                iObj.top = iObj.top - fixPix;
                jQuery(this).closest(".ui-dialog").css("top", iObj.top + "px");
            },
            title: LANG.plugins.davcal['settings'],
            resizable: true,         
            buttons: dialogButtons,
        })
        .html(
            settingsHtml
             )
        .parent()
        .attr('id','dw_davcal__settings')
        .show()
        .appendTo('.dokuwiki:first');
        
        jQuery('#dw_davcal__settings').position({
            my: "center",
            at: "center",
            of: window
        });
        
        // Initialize current settings
         
         if(!JSINFO.plugin.davcal['disable_settings'])
         {
             var $tzdropdown = jQuery('#dw_davcal__settings_timezone');
             jQuery('#fullCalendarTimezoneList option').each(function() {
                 jQuery('<option />', {value: jQuery(this).val(), 
                         text: jQuery(this).text()}).appendTo($tzdropdown);
             });
             
             var $tfdropdown = jQuery('#dw_davcal__settings_timeformat');
             jQuery('<option />', {value: 'lang', text: LANG.plugins.davcal['language_specific']}).appendTo($tfdropdown);
             jQuery('<option />', {value: '24h', text: '24h'}).appendTo($tfdropdown);
             jQuery('<option />', {value: '12h', text: '12h'}).appendTo($tfdropdown);
             
             if(!JSINFO.plugin.davcal['disable_sync'])
             {
                 jQuery('#dw_davcal__settings_syncurl_edit').on('click', function() {
                     jQuery(this).select();
                 });
                 jQuery('#dw_davcal__settings_principalurl_edit').on('click', function() {
                     jQuery(this).select();
                 });
             }
             
             if(!JSINFO.plugin.davcal['disable_ics'])
             {
                 jQuery('#dw_davcal__settings_privateurl_edit').on('click', function() {
                     jQuery(this).select(); 
                 });
             }
             
             if(dw_davcal__modals.settings)
             {
                 if(dw_davcal__modals.settings['timeformat'] !== '')
                     jQuery('#dw_davcal__settings_timeformat').val(dw_davcal__modals.settings['timeformat']);
                 if(dw_davcal__modals.settings['timezone'] !== '')
                     jQuery('#dw_davcal__settings_timezone').val(dw_davcal__modals.settings['timezone']);
                 if(dw_davcal__modals.settings['weeknumbers'] == 1)
                     jQuery('#dw_davcal__settings_weeknumbers').prop('checked', true);
                 else
                     jQuery('#dw_davcal__settings_weeknumbers').prop('checked', false);
                     
                 if(dw_davcal__modals.settings['workweek'] == 1)
                     jQuery('#dw_davcal__settings_workweek').prop('checked', true);
                 else
                     jQuery('#dw_davcal__settings_workweek').prop('checked', false);
                     
                 if(dw_davcal__modals.settings['monday'] == 1)
                     jQuery('#dw_davcal__settings_monday').prop('checked', true);
                 else
                     jQuery('#dw_davcal__settings_monday').prop('checked', false);
                 if(dw_davcal__modals.settings['meta']['forcetimezone'] !== 'no')
                     jQuery('#dw_davcal__settings_timezone').prop('disabled', true);
                 if(dw_davcal__modals.settings['meta']['forcetimeformat'] !== 'no')
                     jQuery('#dw_davcal__settings_timeformat').prop('disabled', true);
             }
         }
 
         // attach event handlers
         jQuery('#dw_davcal__settings .ui-dialog-titlebar-close').click(function(){
           dw_davcal__modals.hideSettingsDialog();
         });
     },
     
     /**
      * Sanity-check our events.
      * 
      * @return boolean false on failure, otherwise true
      */
     checkEvents : function() {
         // Retrieve dates
         var allDay = jQuery('#dw_davcal__allday_edit').prop('checked');
         var startDate = moment(jQuery('#dw_davcal__eventfrom_edit').val(), 'YYYY-MM-DD');
         var endDate = moment(jQuery('#dw_davcal__eventto_edit').val(), 'YYYY-MM-DD');
         
         // Do the checking
         if(!allDay)
         {
             var startTime = moment.duration(jQuery('#dw_davcal__eventfromtime_edit').val());
             var endTime = moment.duration(jQuery('#dw_davcal__eventtotime_edit').val());
             startDate.add(startTime);
             endDate.add(endTime);
         }
         if(!startDate.isValid())
         {
             dw_davcal__modals.msg = LANG.plugins.davcal['start_date_invalid'];
             dw_davcal__modals.showDialog(false);
             return false;
         }
         if(!endDate.isValid())
         {
             dw_davcal__modals.msg = LANG.plugins.davcal['end_date_invalid'];
             dw_davcal__modals.showDialog(false);
             return false;
         }
         if(endDate.isBefore(startDate))
         {
             dw_davcal__modals.msg = LANG.plugins.davcal['end_date_before_start_date'];
             dw_davcal__modals.showDialog(false);
             return false;
         }
         if(!allDay && endDate.isSame(startDate))
         {
             dw_davcal__modals.msg = LANG.plugins.davcal['end_date_is_same_as_start_date'];
             dw_davcal__modals.showDialog(false);
             return false;
         }
         return true;
     },
     
     /**
      * Show the edit event dialog, which is also used to create new events
      * @param {Object} event The event to create, that is the date or the calEvent
      * @param {Object} edit  Whether we edit (true) or create a new event (false)
      */
     showEditEventDialog : function(event, edit) {
         if(dw_davcal__modals.$editEventDialog)
             return;
         
-        var readonly = dw_davcal__modals.settings['readonly'];
+        var readonly = true;
+        for(var i=0; i<dw_davcal__modals.settings['calids'].length; i++)
+        {
+            if(edit)
+            {
+                // Use the specific calendar setting if we edit an event
+                if(event.page == dw_davcal__modals.settings['calids'][i]['page'])
+                  readonly = !dw_davcal__modals.settings['calids'][i]['write'];
+            }
+            else
+            {
+                // If there is at least one writable calendar,
+                // we set readonly to false
+                if(dw_davcal__modals.settings['calids'][i]['write'])
+                  readonly = false;
+            }
+        }
+
         var title = '';   
         var dialogButtons = {};
         var calEvent = [];
         var recurringWarning = '';
         // Buttons are dependent on edit or create
         // Several possibilities:
         //
         // 1) Somebody tries to edit, it is not recurring and not readonly -> show
         // 2) Somebody tries to edit, it is recurring and not readonly -> message
         // 3) Somebody tries to edit, it is readonly -> message
         // 4) Somebody tries to create and it is readonly -> message
         // 5) Somebody tries to create -> show
         if(edit && (event.recurring != true) && (readonly === false))
         {
             calEvent = event;
             title = LANG.plugins.davcal['edit_event'];
             dialogButtons[LANG.plugins.davcal['edit']] = function() {
                 if(!dw_davcal__modals.checkEvents())
                   return;
                 var postArray = { };
                 var attachArr = new Array();
-                var pageid = dw_davcal__modals.page;
-                if(dw_davcal__modals.settings['multi'])
-                {
-                    pageid = jQuery("#dw_davcal__editevent_calendar option:selected").val();
-                }
+                var pageid = calEvent.page;
+
                 jQuery('.dw_davcal__editevent_attachment_link').each(function() {
                     var attachment = jQuery(this).attr('href');
                     if(attachment != undefined)
                     {
                         attachArr.push(attachment);
                     }
                 });
                 postArray['attachments'] = attachArr;
                 jQuery("input.dw_davcal__editevent, textarea.dw_davcal__editevent").each(function() {
                   if(jQuery(this).attr('type') == 'checkbox')
                   {
                       postArray[jQuery(this).prop('name')] = jQuery(this).prop('checked') ? 1 : 0;
                   }
                   else
                   {
                       postArray[jQuery(this).prop('name')] = jQuery(this).val();
                   }
                 });
                 jQuery('#dw_davcal__ajaxedit').html('<img src="'+DOKU_BASE+'lib/images/throbber.gif" alt="" width="16" height="16" />');
                 jQuery.post(
                     DOKU_BASE + 'lib/exe/ajax.php',
                     {
                         call: 'plugin_davcal',
                         id: pageid,
                         page: dw_davcal__modals.page,
                         action: 'editEvent',
                         params: postArray,
                         sectok: JSINFO.plugin.davcal['sectok']
                     },
                     function(data)
                     {
                         var result = data['result'];
                         var html = data['html'];
                         jQuery('#dw_davcal__ajaxedit').html(html);
                         if(result === true)
                         {
                             jQuery('#fullCalendar').fullCalendar('refetchEvents');
                             dw_davcal__modals.hideEditEventDialog();
                         }
                     }
                 );
             };
             dialogButtons[LANG.plugins.davcal['delete']] = function() {
                 dw_davcal__modals.action = 'deleteEvent';
                 dw_davcal__modals.msg = LANG.plugins.davcal['really_delete_this_event'];
                 dw_davcal__modals.completeCb = function(data) {
                     var result = data['result'];
                     var html = data['html'];
                     jQuery('#dw_davcal__ajaxedit').html(html);                    
                     if(result === true)
                     {
                         jQuery('#fullCalendar').fullCalendar('refetchEvents');
                         dw_davcal__modals.hideEditEventDialog();
                     }
                 };
                 dw_davcal__modals.showDialog(true);
             };
         }
         else if(edit && (event.recurring == true) && (readonly === false))
         {
             calEvent = event;
             title = LANG.plugins.davcal['edit_event'];
             recurringWarning = LANG.plugins.davcal['recurring_cant_edit'];
         }
         else if(edit && (readonly === true))
         {
             calEvent = event;
             title = LANG.plugins.davcal['edit_event'];
             recurringWarning = LANG.plugins.davcal['no_permission'];
         }
         else if(readonly === true)
         {
             calEvent.start = event;
             calEvent.end = moment(event);
             calEvent.start.hour(12);
             calEvent.start.minute(0);
             calEvent.end.hour(13);
             calEvent.end.minute(0);
             calEvent.allDay = false;
             calEvent.recurring = false;
             calEvent.title = '';
             calEvent.description = '';
             calEvent.id = '0';
             calEvent.page = dw_davcal__modals.page;
             title = LANG.plugins.davcal['create_new_event'];
             recurringWarning = LANG.plugins.davcal['no_permission'];
         }
         else
         {
             calEvent.start = event;
             calEvent.end = moment(event);
             calEvent.start.hour(12);
             calEvent.start.minute(0);
             calEvent.end.hour(13);
             calEvent.end.minute(0);
             calEvent.allDay = false;
             calEvent.recurring = false;
             calEvent.title = '';
             calEvent.description = '';
             calEvent.id = '0';
             calEvent.page = dw_davcal__modals.settings['calids'][0]['page'];
             title = LANG.plugins.davcal['create_new_event'];
             dialogButtons[LANG.plugins.davcal['create']] = function() {
                 if(!dw_davcal__modals.checkEvents())
                   return;
 
                 var postArray = { };
-                var pageid = dw_davcal__modals.page;
-                var attachArr = new Array();
-                if(dw_davcal__modals.settings['multi'])
-                {
-                    pageid = jQuery("#dw_davcal__editevent_calendar option:selected").val();
-                }
+                var pageid = jQuery("#dw_davcal__editevent_calendar option:selected").val();
                 jQuery("input.dw_davcal__editevent, textarea.dw_davcal__editevent").each(function() {
                   if(jQuery(this).attr('type') == 'checkbox')
                   {
                       postArray[jQuery(this).prop('name')] = jQuery(this).prop('checked') ? 1 : 0;
                   }
                   else
                   {
                       postArray[jQuery(this).prop('name')] = jQuery(this).val();
                   }
                 });
                 jQuery('.dw_davcal__editevent_attachment_link').each(function() {
                     var attachment = jQuery(this).attr('href');
                     if(attachment != undefined)
                     {
                         attachArr.push(attachment);
                     }
                 });
                 postArray['attachments'] = attachArr;
                 jQuery('#dw_davcal__ajaxedit').html('<img src="'+DOKU_BASE+'lib/images/throbber.gif" alt="" width="16" height="16" />');
                 jQuery.post(
                     DOKU_BASE + 'lib/exe/ajax.php',
                     {
                         call: 'plugin_davcal',
                         id: pageid,
                         page: dw_davcal__modals.page,
                         action: 'newEvent',
                         params: postArray,
                         sectok: JSINFO.plugin.davcal['sectok']
                     },
                     function(data)
                     {
                         var result = data['result'];
                         var html = data['html'];
                         jQuery('#dw_davcal__ajaxedit').html(html);
                         if(result === true)
                         {
                             jQuery('#fullCalendar').fullCalendar('refetchEvents');
                             dw_davcal__modals.hideEditEventDialog();
                         }
                     }
                 );
             };
         }
         dialogButtons[LANG.plugins.davcal['cancel']] = function() {
             dw_davcal__modals.hideEditEventDialog();
         };
         dw_davcal__modals.uid = calEvent.id;
         dw_davcal__modals.$editEventDialog = jQuery(document.createElement('div'))
        .dialog({
            autoOpen: false,
            draggable: true,
            // fix for dragging: http://stackoverflow.com/questions/17247486/jquery-ui-dialog-dragging-issues
            drag: function(event, ui) {
                var fixPix = jQuery(document).scrollTop();
                iObj = ui.position;
                iObj.top = iObj.top - fixPix;
                jQuery(this).closest(".ui-dialog").css("top", iObj.top + "px");
            },
            title: title,
            resizable: true,         
            buttons: dialogButtons,
        })
        .html(
             '<div><table>' + 
             '<tr><td>' + LANG.plugins.davcal['calendar'] + '</td><td><select id="dw_davcal__editevent_calendar"></select></td></tr>' +
             '<tr><td>' + LANG.plugins.davcal['title'] + '</td><td><input type="text" id="dw_davcal__eventname_edit" name="eventname" class="dw_davcal__editevent"></td></tr>' +
             '<tr><td>' + LANG.plugins.davcal['description'] + '</td><td><textarea name="eventdescription" id="dw_davcal__eventdescription_edit" class="dw_davcal__editevent dw_davcal__text"></textarea></td></tr>' +
             '<tr><td>' + LANG.plugins.davcal['from'] + '</td><td><input type="text" name="eventfrom" id="dw_davcal__eventfrom_edit" class="dw_davcal__editevent dw_davcal__date"><input type="text" name="eventfromtime" id="dw_davcal__eventfromtime_edit" class="dw_davcal__editevent dw_davcal__time"></td></tr>' +
             '<tr><td>' + LANG.plugins.davcal['to'] + '</td><td><input type="text" name="eventto" id="dw_davcal__eventto_edit" class="dw_davcal__editevent dw_davcal__date"><input type="text" name="eventtotime" id="dw_davcal__eventtotime_edit" class="dw_davcal__editevent dw_davcal__time"></td></tr>' +
             '<tr><td colspan="2"><input type="checkbox" name="allday" id="dw_davcal__allday_edit" class="dw_davcal__editevent">' + LANG.plugins.davcal['allday'] + '</td></tr>' +
             '<tr><td>' + LANG.plugins.davcal['attachments'] + '</td><td><table id="dw_davcal__editevent_attachments"><tbody><tr><td><input type="text" id="dw_davcal__editevent_attachment" value="http://"></td><td><a href="#" id="dw_davcal__editevent_attach">' + LANG.plugins.davcal['add_attachment'] + '</a></td></tr></tbody></table></td></tr>' +
             '</table>' +
             recurringWarning + 
             '<input type="hidden" name="uid" id="dw_davcal__uid_edit" class="dw_davcal__editevent">' +
             '<input type="hidden" name="detectedtz" id="dw_davcal__tz_edit" class="dw_davcal__editevent">' +
             '<input type="hidden" name="currenttz" id="dw_davcal__currenttz_edit" class="dw_davcal__editevent">' +
             '</div>' +
             '<div id="dw_davcal__ajaxedit"></div>'
             )
        .parent()
        .attr('id','dw_davcal__edit')
        .show()
        .appendTo('.dokuwiki:first');
        
        jQuery('#dw_davcal__edit').position({
            my: "center",
            at: "center",
            of: window
        });
        
        // Populate calendar dropdown
        var $dropdown = jQuery("#dw_davcal__editevent_calendar");
        for(var i=0; i<dw_davcal__modals.settings['calids'].length; i++)
        {
            var sel = '';
            // When creating an event, do not show read-only calendars
            if(!edit && (dw_davcal__modals.settings['calids'][i]['write'] === false))
              continue;
            if(calEvent.page == dw_davcal__modals.settings['calids'][i]['page'])
              sel = ' selected="selected"';
            $dropdown.append('<option value="' + dw_davcal__modals.settings['calids'][i]['page'] + '"' + sel + '>' + dw_davcal__modals.settings['calids'][i]['name'] + '</option>');
        }
        if(edit || (dw_davcal__modals.settings['calids'].length < 1))
        {
            $dropdown.prop('disabled', true);
        }
        
        // Set up existing/predefined values
        jQuery('#dw_davcal__tz_edit').val(dw_davcal__modals.detectedTz);
        jQuery('#dw_davcal__currenttz_edit').val(dw_davcal__modals.currentTz);
        jQuery('#dw_davcal__uid_edit').val(calEvent.id);
        jQuery('#dw_davcal__eventname_edit').val(calEvent.title);
        jQuery('#dw_davcal__eventfrom_edit').val(calEvent.start.format('YYYY-MM-DD'));
        jQuery('#dw_davcal__eventfromtime_edit').val(calEvent.start.format('HH:mm'));
        jQuery('#dw_davcal__eventdescription_edit').val(calEvent.description);
        if(calEvent.attachments && (calEvent.attachments !== null))
        {
            for(var i=0; i<calEvent.attachments.length; i++)
            {
                var url = calEvent.attachments[i];
                var row = '<tr><td><a href="' + url + '" class="dw_davcal__editevent_attachment_link">' + url + '</a></td><td><a class="deleteLink" href="#">' + LANG.plugins.davcal['delete'] + '</a></td></tr>';
                jQuery('#dw_davcal__editevent_attachments > tbody:last').append(row);
 
            }
        }
        dw_davcal__modals.attachAttachmentDeleteHandlers();
        jQuery('#dw_davcal__editevent_attach').on("click", function(e)
        {
            e.preventDefault();
            var url = jQuery('#dw_davcal__editevent_attachment').val();
            if(url == '')
              return false;
            jQuery('#dw_davcal__editevent_attachment').val('http://');
            var row = '<tr><td><a href="' + url + '" class="dw_davcal__editevent_attachment_link">' + url + '</a></td><td><a class="deleteLink" href="#">' + LANG.plugins.davcal['delete'] + '</a></td></tr>';
            jQuery('#dw_davcal__editevent_attachments > tbody:last').append(row);
            dw_davcal__modals.attachAttachmentDeleteHandlers();
            return false;
        });
        if(calEvent.allDay && (calEvent.end === null))
        {
            jQuery('#dw_davcal__eventto_edit').val(calEvent.start.format('YYYY-MM-DD'));
            jQuery('#dw_davcal__eventtotime_edit').val(calEvent.start.format('HH:mm'));
        }
        else if(calEvent.allDay)
        {
            endEvent = moment(calEvent.end);
            endEvent.subtract(1, 'days');
            jQuery('#dw_davcal__eventto_edit').val(endEvent.format('YYYY-MM-DD'));
            jQuery('#dw_davcal__eventotime_edit').val(endEvent.format('HH:mm'));
        }
        else
        {
            jQuery('#dw_davcal__eventto_edit').val(calEvent.end.format('YYYY-MM-DD'));
            jQuery('#dw_davcal__eventtotime_edit').val(calEvent.end.format('HH:mm'));
        }
        jQuery('#dw_davcal__allday_edit').prop('checked', calEvent.allDay);
        
         // attach event handlers
         jQuery('#dw_davcal__edit .ui-dialog-titlebar-close').click(function(){
           dw_davcal__modals.hideEditEventDialog();
         });
         jQuery('#dw_davcal__eventfrom_edit').datetimepicker({format:'YYYY-MM-DD',
                                                       formatDate:'YYYY-MM-DD',
                                                       datepicker: true,
                                                       timepicker: false,
                                                       });
         jQuery('#dw_davcal__eventfromtime_edit').datetimepicker({format:'HH:mm',
                                                       formatTime:'HH:mm',
                                                       datepicker: false,
                                                       timepicker: true,
                                                       step: 15});
         jQuery('#dw_davcal__eventto_edit').datetimepicker({format:'YYYY-MM-DD',
                                                       formatDate:'YYYY-MM-DD',
                                                       datepicker: true,
                                                       timepicker: false,
                                                       });
         jQuery('#dw_davcal__eventtotime_edit').datetimepicker({format:'HH:mm',
                                                       formatTime:'HH:mm',
                                                       datepicker: false,
                                                       timepicker: true,
                                                       step:15});
         jQuery('#dw_davcal__allday_edit').change(function() {
             if(jQuery(this).is(":checked"))
             {
                 jQuery('#dw_davcal__eventfromtime_edit').prop('readonly', true);
                 jQuery('#dw_davcal__eventtotime_edit').prop('readonly', true);
             }
             else
             {
                 jQuery('#dw_davcal__eventfromtime_edit').prop('readonly', false);
                 jQuery('#dw_davcal__eventtotime_edit').prop('readonly', false);
             }
         });
         jQuery('#dw_davcal__allday_edit').change();
     },
     
     /**
      * Attach handles to delete the attachments to all 'delete' links
      */
     attachAttachmentDeleteHandlers: function()
     {
        jQuery("#dw_davcal__editevent_attachments .deleteLink").on("click", function(e)
        {
             e.preventDefault();
             var tr = jQuery(this).closest('tr');
             tr.css("background-color", "#FF3700");
             tr.fadeOut(400, function()
             {
                 tr.remove();
             });
             return false;
        });
     },
     
     /**
      * Show an info/confirmation dialog
      * @param {Object} confirm Whether a confirmation dialog (true) or an info dialog (false) is requested
      */
     showDialog : function(confirm)
     {
         if(dw_davcal__modals.$confirmDialog)
             return;
         var dialogButtons = {};
         var title = '';
         if(confirm)
         {
             title = LANG.plugins.davcal['confirmation'];
-            var pageid = dw_davcal__modals.page;
-            if(dw_davcal__modals.settings['multi'])
-            {
-                pageid = jQuery("#dw_davcal__editevent_calendar option:selected").val();
-            }
+            var pageid = jQuery("#dw_davcal__editevent_calendar option:selected").val();
             dialogButtons[LANG.plugins.davcal['yes']] =  function() {
                             jQuery.post(
                                 DOKU_BASE + 'lib/exe/ajax.php',
                                 {
                                     call: 'plugin_davcal',
                                     id: pageid,
                                     page: dw_davcal__modals.page,
                                     action: dw_davcal__modals.action,
                                     params: {
                                         uid: dw_davcal__modals.uid
                                     },
                                     sectok: JSINFO.plugin.davcal['sectok']
                                 },
                                 function(data)
                                 {
                                     dw_davcal__modals.completeCb(data);
                                 }
                             );
                             dw_davcal__modals.hideDialog();
                     };
             dialogButtons[LANG.plugins.davcal['cancel']] = function() {
                             dw_davcal__modals.hideDialog();
                     };
         }
         else
         {
             title = LANG.plugins.davcal['info'];
             dialogButtons[LANG.plugins.davcal['ok']] = function() {
                  dw_davcal__modals.hideDialog();
             };
         }
         dw_davcal__modals.$dialog = jQuery(document.createElement('div'))
             .dialog({
                 autoOpen: false,
                 draggable: true,
                 //fix for dragging: http://stackoverflow.com/questions/17247486/jquery-ui-dialog-dragging-issues
                 drag: function(event, ui) {
                     var fixPix = jQuery(document).scrollTop();
                     iObj = ui.position;
                     iObj.top = iObj.top - fixPix;
                     jQuery(this).closest(".ui-dialog").css("top", iObj.top + "px");
                 },
                 title: title,
                 resizable: true,
                 buttons: dialogButtons,
             })
             .html(
                 '<div>' + dw_davcal__modals.msg + '</div>'
             )
             .parent()
             .attr('id','dw_davcal__confirm')
             .show()
             .appendTo('.dokuwiki:first');
    
             jQuery('#dw_davcal__confirm').position({
                 my: "center",
                 at: "center",
                 of: window
             });
                  // attach event handlers
             jQuery('#dw_davcal__confirm .ui-dialog-titlebar-close').click(function(){
                 dw_davcal__modals.hideDialog();
             });
     },
     
     /**
      * Hide the edit event dialog
      */
     hideEditEventDialog : function() {
         dw_davcal__modals.$editEventDialog.empty();
         dw_davcal__modals.$editEventDialog.remove();
         dw_davcal__modals.$editEventDialog = null;
     },
     
     /**
      * Hide the confirm/info dialog
      */
     hideDialog: function() {
         dw_davcal__modals.$dialog.empty();
         dw_davcal__modals.$dialog.remove();
         dw_davcal__modals.$dialog = null;
     },
     
     /**
      * Hide the settings dialog
      */
     hideSettingsDialog: function() {
         dw_davcal__modals.$settingsDialog.empty();
         dw_davcal__modals.$settingsDialog.remove();
         dw_davcal__modals.$settingsDialog = null;
     }
 };