public function getUser()
    {
        if (null === $this->user && $this->isLogin()) {
            $username = Base::instance()->get(static::SESSION_USER);
            $this->user = Security::instance()->getUserProvider()->loadByUsername($username);

            try {
                Authentication::instance()->checkUser($this->user);
            } catch(Exception $e) {
                $this->user = null;
            }
        }

        return $this->user;
    }