_replace($google_font[2], $file_url, $google_font[0]);

                //async
                if(!empty(Config::$options['fonts']['async'])) {
                    $new_google_font = preg_replace(array('#media=([\'"]).+?\1#', '#onload=([\'"]).+?\1#'), '', $new_google_font);
                    $new_google_font = str_replace('<link', '<link media="print" onload="this.media=\'all\';this.onload=null;"', $new_google_font);
                }

                //replace original font tag
                $html = str_replace($google_font[0], $new_google_font, $html);
            }
        }

        return $html;
    }

    //download and save google font css file
    private static function download_google_font($url, $file_path)
    {
        //add https if using relative scheme
        if(substr($url, 0, 2) === '//') {
            $url = 'https:' . $url;
        }

        //download css file
        $css_response = wp_remote_get(html_entity_decode($url), array('user-agent' => 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/111.0.0.0 Safari/537.36'));

        //check valid response
        if(wp_remote_retrieve_response_code($css_response) !== 200) {
            return false;
        }

        //css content
        $css = $css_response['body'];

        //find font files inside the css
        $regex = '/url\((https:\/\/fonts\.gstatic\.com\/.*?)\)/';
        preg_match_all($regex, $css, $matches);
        $font_urls = array_unique($matches[1]);

        $font_requests = array();
        foreach($font_urls as $font_url) {

            if(!file_exists(PERFMATTERS_CACHE_DIR . 'fonts/' . basename($font_url))) {
                $font_requests[] = array('url' => $font_url, 'type' => 'GET');
            }

            $cached_font_url = self::$font_file_cache_url . 'fonts/' . basename($font_url);
            $css = str_replace($font_url, $cached_font_url, $css);
        }

        //download new font files to cache directory
        if(method_exists(WpOrg\Requests\Requests::class, 'request_multiple')) { //wp 6.2+
            $font_responses = WpOrg\Requests\Requests::request_multiple($font_requests);
        }
        elseif(method_exists(RequestsOld::class, 'request_multiple')) { //deprecated
            $font_responses = RequestsOld::request_multiple($font_requests);
        }   

        if(!empty($font_responses)) {
            foreach($font_responses as $font_response) {
                if(is_a($font_response, 'Requests_Response') || is_a($font_response, 'WpOrg\Requests\Response')) {
                    $font_path = PERFMATTERS_CACHE_DIR . 'fonts/' . basename($font_response->url);

                    //save font file
                    file_put_contents($font_path, $font_response->body);
                }
            }
        }

        //save final css file
        file_put_contents($file_path, $css);

        return true;
    }

    //delete all files in the fonts cache directory
    public static function clear_local_fonts()
    {
        $files = glob(PERFMATTERS_CACHE_DIR . 'fonts/*');
        foreach($files as $file) {
            if(is_file($file)) {
                unlink($file);
            }
        }
    }
}