protected function validateFiles(array &$library)
    {
        if (empty($library['files'])) {
            return true; // Assume files will be loaded dynamically
        }

        $readable = $count = 0;

        foreach ($library['files'] as &$file) {

            $count++;

            if (!gplcart_path_is_absolute($file)) {
                $file = $library['basepath'] . "/$file";
            }

            $readable += (int) (is_file($file) && is_readable($file));
        }

        return $count == $readable;
    }