function update_chat_user($data)
 {
     $nickname = $data['nickname'];
     $status = ${$data}['status'];
     $color = $data['color'];
     $time = time();
     $db =& db_factory::instance();
     $sql = "UPDATE chat_user \n\t\t\t\t\t\tSET time={$time}, status = {$status},\n\t\t\t\t\t\t\tcolor = {$color}, nickname = {$nickname},\n\t\t\t\t\t\tWHERE id='{$chat_user_id}'";
     $db->sql_exec($sql);
     chat_user::_set_session_chat_user_data($row);
 }
 function leave_chat_room()
 {
     $chat_user_data = chat_user::get_chat_user_data();
     chat_system::leave_chat_room($chat_user_data['id'], $chat_user_data['nickname'], $chat_user_data['chat_room_id']);
     $chat_user_data['chat_room_id'] = 0;
     chat_user::_set_session_chat_user_data($chat_user_data);
 }