protected function _parseAssetCallback($m) {
        if (Config::config()['user']['output']['asset']['enabled']) {
            $data = ['type' => $m[1], 'cache' => $m[3], 'files' => explode(',', $m[2])];

            $asset = new Asset($data);

            if ($m[1] == 'css') {
                return '<link href="{{url:.Gcs.gcs.asset.default:\'' . $asset->getId() . '\',\'' . $asset->getType() . '\'}}" rel="stylesheet" media="screen" type="text/css" />';
            }
            else if ($m[1] == 'js') {
                return '<script type="text/javascript" defer src="{{url:.Gcs.gcs.asset.default:\'' . $asset->getId() . '\',\'' . $asset->getType() . '\'}}" ></script>';
            }
        }
        else {
            $content = '';
            $files = explode(',', $m[2]);

            foreach ($files as $value) {
                $value = preg_replace('#\\n#isU', '', $value);
                $value = preg_replace('#\\r#isU', '', $value);
                $value = preg_replace('#\\t#isU', '', $value);

                if ($m[1] == 'css') {
                    $content .= '<link href="/' . trim($value) . '" rel="stylesheet" media="screen" type="text/css" />' . "\n";
                }
                else {
                    $content .= '<script type="text/javascript" defer src="/' . trim($value) . '"></script>' . "\n";
                }
            }

            return $content;
        }

        return '';
    }