public function message($message = null, $level = null)
    {
        // If no message was provided, we should update
        // the most recently added message.
        if (!$message) {
            return $this->updateLastMessage(compact('level'));
        }

        if (!$message instanceof Message) {
            $message = new Message(compact('message', 'level'));
        }

        $this->messages()->push($message);

        return $this->flash();
    }