/**
  * Sync calendar
  * @param ilCalendarCategory $cat 
  */
 protected function doSynchronisation(ilCalendarCategory $category)
 {
     include_once './Services/Calendar/classes/class.ilCalendarRemoteReader.php';
     $remote = new ilCalendarRemoteReader($category->getRemoteUrl());
     $remote->setUser($category->getRemoteUser());
     $remote->setPass($category->getRemotePass());
     $remote->read();
     $remote->import($category);
 }
 /**
  * Sync external calendars
  */
 protected function synchroniseExternalCalendars()
 {
     global $ilUser;
     if (!ilCalendarSettings::_getInstance()->isWebCalSyncEnabled()) {
         return false;
     }
     // @todo make this thread safe
     $limit = new ilDateTime(time(), IL_CAL_UNIX);
     $limit->increment(IL_CAL_HOUR, -1 * ilCalendarSettings::_getInstance()->getWebCalSyncHours());
     $cats = ilCalendarCategories::_getInstance($ilUser->getId());
     foreach ($cats->getCategoriesInfo() as $cat_id => $info) {
         if ($info['remote']) {
             // Check for execution
             $category = new ilCalendarCategory($cat_id);
             if (ilDateTime::_before($category->getRemoteSyncLastExecution(), $limit)) {
                 // update in any case to avoid multiple updates of invalid calendar sources.
                 $category->setRemoteSyncLastExecution(new ilDateTime(time(), IL_CAL_UNIX));
                 $category->update();
                 include_once './Services/Calendar/classes/class.ilCalendarRemoteReader.php';
                 $remote = new ilCalendarRemoteReader($category->getRemoteUrl());
                 $remote->setUser($category->getRemoteUser());
                 $remote->setPass($category->getRemotePass());
                 $remote->read();
                 $remote->import($category);
                 break;
             }
         }
     }
 }