/**
  * @param Model_Contest $contest
  * @throws Exception_Page
  */
 protected function check_permission($contest)
 {
     $current_user = $this->get_current_user();
     if ($contest and $contest->can_user_access($current_user)) {
         return;
     }
     //TODO: add more notice
     if ($current_user) {
         $message = __('common.contest_private');
     } else {
         $message = __('common.contest_login_first');
     }
     throw new Exception_Page($message);
 }