private function setAndValidateChatSession($id)
 {
     session_start();
     if (!isset($_SESSION['timestamp' . $id])) {
         $_SESSION['timestamp' . $id] = time();
         ChatRoomMember::updateUserCurrentChatroomStatus(1, $id);
     }
     if (time() - $_SESSION['timestamp' . $id] > 100) {
         session_unset();
         // unset $_SESSION variable for the run-time
         session_destroy();
         ChatRoomMember::updateUserCurrentChatroomStatus(0, $id);
         return true;
     }
 }