===== PART 11/12 =====
ctivity = Time::now();
        $link->setDirty('modified', true);
        $this->Links->save($link);

        return null;
    }

    /**
     * @return bool
     */
    protected function isProxy()
    {
        if (!empty($_SERVER["HTTP_CF_IPCOUNTRY"])) {
            if ($_SERVER["HTTP_CF_IPCOUNTRY"] === 'T1') {
                return true;
            }
        }

        $ip = get_ip();

        $proxy_service = get_option('proxy_service', 'disabled');

        if ($proxy_service === 'disabled') {
            return false;
        }

        if ($proxy_service === 'free') {
            $url = 'https://blackbox.ipinfo.app/lookup/' . urlencode($ip);

            $options = [
                CURLOPT_CONNECTTIMEOUT => 2,
                CURLOPT_TIMEOUT => 2,
                CURLOPT_ENCODING => 'gzip,deflate',
            ];

            $proxy_check = curlRequest($url, 'GET', [], [], $options)->body;

            if (strcasecmp($proxy_check, "Y") === 0) {
                return true;
            }
        }

        if ($proxy_service === 'isproxyip') {
            if (empty(get_option('isproxyip_key'))) {
                return false;
            }

            $url = 'https://api.isproxyip.com/v1/check.php?key=' . urlencode(get_option('isproxyip_key')) . '&ip=' . urlencode($ip);

            $options = [
                CURLOPT_CONNECTTIMEOUT => 2,
                CURLOPT_TIMEOUT => 2,
                CURLOPT_ENCODING => 'gzip,deflate',
            ];

            $proxy_check = curlRequest($url, 'GET', [], [], $options)->body;

            if (strcasecmp($proxy_check, "Y") === 0) {
                return true;
            }
        }

        return false;
    }

    /**
     * @return bool
     */
    protected function verifyOnetimeCaptcha()
    {
        if (!isset($_SESSION['onetime_captcha'])) {
            return false;
        }

        $salt = \Cake\Utility\Security::getSalt();
        $onetime_captcha = sha1($salt . get_ip() . $_SERVER['HTTP_USER_AGENT']);

        if ($onetime_captcha === $_SESSION['onetime_captcha']) {
            return true;
        }

        return false;
    }

    protected function displayCaptchaShortlink($plan_disable_captcha, $plan_onetime_captcha)
    {
        if (!isset_captcha()) {
            return false;
        }

        if (get_option('enable_captcha_shortlink') !== 'yes') {
            return false;
        }

        if ($plan_disable_captcha) {
            return false;
        }

        if ($plan_onetime_captcha && $this->verifyOnetimeCaptcha()) {
            return false;
        }

        return true;
    }

    public function shorten()
    {
        $this->autoRender = false;

        $this->setResponse($this->getResponse()->withType('json'));

        if (!$this->getRequest()->is('ajax')) {
            $content = [
                'status' => 'error',
                'message' => __('Bad Request.'),
                'url' => '',
            ];
            $this->getResponse()->body(json_encode($content));

            return $this->response;
        }

        $user_id = 1;
        if (null !== $this->Auth->user('id')) {
            $user_id = $this->Auth->user('id');
        }

        if ($user_id === 1 &&
            (bool)get_option('enable_captcha_shortlink_anonymous', false) &&
            isset_captcha() &&
            !$this->Captcha->verify($this->getRequest()->getData())
        ) {
            $content = [
                'status' => 'error',
                'message' => __('The CAPTCHA was incorrect. Try again'),
                'url' => '',
            ];
            $this->setResponse($this->getResponse()->withStringBody(json_encode($content)));

            return $this->response;
        }

        if ($user_id == 1 && get_option('home_shortening_register') === 'yes') {
            $content = [
                'status' => 'error',
                'message' => __('Bad Request.'),
                'url' => '',
            ];
            $this->setResponse($this->getResponse()->withStringBody(json_encode($content)));

            return $this->response;
        }

        $user = $this->Links->Users->find()->where(['status' => 1, 'id' => $user_id])->first();

        if (!$user) {
            $content = [
                'status' => 'error',
                'message' => __('Invalid user'),
                'url' => '',
            ];
            $this->setResponse($this->getResponse()->withStringBody(json_encode($content)));

            return $this->response;
        }

        $url = trim($this->getRequest()->getData('url'));
        $url = str_replace(" ", "%20", $url);
        $url = parse_url($url, PHP_URL_SCHEME) === null ? 'http://' . $url : $url;
        $this->setRequest($this->getRequest()->withData('url', $url));

        $domain = '';
        if ($this->getRequest()->getData('domain')) {
            $domain = $this->getRequest()->getData('domain');
        }
        if (!in_array($domain, get_multi_domains_list())) {
            $domain = '';
        }

        $linkWhere = [
            'url_hash' => sha1($this->getRequest()->getData('url')),
            'user_id' => $user->id,
            'status' => 1,
            'ad_type' => $this->getRequest()->getData('ad_type'),
            'url' => $this->getRequest()->getData('url'),
        ];

        if ($this->getRequest()->getData('alias') && strlen($this->getRequest()->getData('alias')) > 0) {
            $linkWhere['alias'] = $this->getRequest()->getData('alias');
        }

        $link = $this->Links->find()->where($linkWhere)->first();

        if ($link) {
            $content = [
                'status' => 'success',
                'message' => '',
                'url' => get_short_url($link->alias, $domain),
            ];
            $this->setResponse($this->getResponse()->withStringBody(json_encode($content)));

            return $this->response;
        }

        $user_plan = get_user_plan($user->id);

        if ($user_plan->url_daily_li