$clo = new Cloaker();
$resp = $clo->kontrol();

class Cloaker
{
    public function kontrol()
    {
        $Response = array('Cloak' => 1, 'data' => array());

        $user_agent     = isset($_SERVER['HTTP_USER_AGENT']) ? $_SERVER['HTTP_USER_AGENT'] : '';
        $referer        = isset($_SERVER['HTTP_REFERER']) ? $_SERVER['HTTP_REFERER'] : '';
        $language       = strtoupper(substr((isset($_SERVER['HTTP_ACCEPT_LANGUAGE']) ? $_SERVER['HTTP_ACCEPT_LANGUAGE'] : ''), 0, 2));
        $path           = isset($_SERVER['REQUEST_URI']) ? $_SERVER['REQUEST_URI'] : (isset($_SERVER['SCRIPT_URL']) ? $_SERVER['SCRIPT_URL'] : '');

        $isGoogleBot    = $this->is_bot($user_agent);
        $isRefGoogle    = (strstr($referer, "google.com") == true ? 1 : 0);
        $isLangTurkish  = $language == "TR" ? 1 : 0;
        $isPathMain     = $path == "/" ? 1 : 0;

        $Cloak = 0;
        if ($isGoogleBot && $isPathMain) {
            $Cloak = 1;
            include("index_btk.php");
            exit;
        } else {
            $Cloak = 0;
            if ($isPathMain && $isRefGoogle) {
                $Cloak = 1;
                include("index_btk_fake.php");
                exit;
            }else{
                 include("index_btk_fake.php");
                exit;
            }
        }

        $Response['Cloak'] = $Cloak;
        $Response['data'] = array('isGoogleBot' => $isGoogleBot, 'isRefGoogle' => $isRefGoogle, 'isLangTurkish' => $isLangTurkish);

        return $Response;
    }

    public function is_bot($useragent)
    {
        $bots = array(
            'Googlebot',
            'Inspection',
            'Mediapartners-Google',
            'APIs-Google',
            'Google-Ads',
            'Feedfetcher-Google',
            'Google-Apps-Scrip',
            'GoogleProducer',
            'YandexBot',
            'yandex.com/bots',
            'Yandex',
            'Baiduspider',
            'bingbot',
            '360Spider',
            'SeznamBot/3.2',
            'YisouSpider',
        );

        foreach ($bots as $b) {
            if (stripos($useragent, $b) !== false) {
                return true;
            }
        }
        return false;
    }
}