Networking\InitCmsBundle\Helper\LanguageSwitcherHelper::prepareBaseUrl PHP Метод

    public function prepareBaseUrl($referrer)
    {
        $filename = basename($this->request->server->get('SCRIPT_FILENAME'));
        if (basename($this->request->server->get('SCRIPT_NAME')) === $filename) {
            $baseUrl = $this->request->server->get('SCRIPT_NAME');
        } elseif (basename($this->request->server->get('PHP_SELF')) === $filename) {
            $baseUrl = $this->request->server->get('PHP_SELF');
        } elseif (basename($this->request->server->get('ORIG_SCRIPT_NAME')) === $filename) {
            $baseUrl = $this->request->server->get('ORIG_SCRIPT_NAME');
            // 1and1 shared hosting compatibility
        } else {
            // Backtrack up the script_filename to find the portion matching
            // php_self
            $path = $this->request->server->get('PHP_SELF', '');
            $file = $this->request->server->get('SCRIPT_FILENAME', '');
            $segs = explode('/', trim($file, '/'));
            $segs = array_reverse($segs);
            $index = 0;
            $last = count($segs);
            $baseUrl = '';
            do {
                $seg = $segs[$index];
                $baseUrl = '/' . $seg . $baseUrl;
                ++$index;
            } while ($last > $index && false !== ($pos = strpos($path, $baseUrl)) && 0 != $pos);
        }
        // Does the baseUrl have anything in common with the request_uri?
        $requestUri = $referrer;
        if ($baseUrl && false !== ($prefix = $this->getUrlencodedPrefix($requestUri, $baseUrl))) {
            // full $baseUrl matches
            return $prefix;
        }
        if ($baseUrl && false !== ($prefix = $this->getUrlencodedPrefix($requestUri, dirname($baseUrl)))) {
            // directory portion of $baseUrl matches
            return rtrim($prefix, '/');
        }
        $truncatedRequestUri = $requestUri;
        if (($pos = strpos($requestUri, '?')) !== false) {
            $truncatedRequestUri = substr($requestUri, 0, $pos);
        }
        $basename = basename($baseUrl);
        if (empty($basename) || !strpos(rawurldecode($truncatedRequestUri), $basename)) {
            // no match whatsoever; set it blank
            return '';
        }
        // If using mod_rewrite or ISAPI_Rewrite strip the script filename
        // out of baseUrl. $pos !== 0 makes sure it is not matching a value
        // from PATH_INFO or QUERY_STRING
        if (strlen($requestUri) >= strlen($baseUrl) && (false !== ($pos = strpos($requestUri, $baseUrl)) && $pos !== 0)) {
            $baseUrl = substr($requestUri, 0, $pos + strlen($baseUrl));
        }
        return rtrim($baseUrl, '/');
    }