/**
  * Load the user object into the user property
  * 
  * @return TBGUser
  */
 public static function loadUser($user = null)
 {
     try {
         self::$_user = $user === null ? TBGUser::loginCheck(self::getRequest()->getParameter('tbg3_username'), self::getRequest()->getParameter('tbg3_password')) : $user;
         if (self::$_user->isAuthenticated()) {
             if (self::$_user->isOffline() || self::$_user->isAway()) {
                 self::$_user->setOnline();
             }
             self::$_user->updateLastSeen();
             self::$_user->setTimezone(TBGSettings::getUserTimezone());
             self::$_user->setLanguage(TBGSettings::getUserLanguage());
             self::$_user->save();
             if (!self::$_user->getGroup() instanceof TBGGroup) {
                 throw new Exception('This user account belongs to a group that does not exist anymore. <br>Please contact the system administrator.');
             }
         }
     } catch (Exception $e) {
         throw $e;
     }
     return self::$_user;
 }