public static function parseTag($tag)
    {
        $tag = explode('_', strtr(trim($tag), '-', '_'));
        $language = self::getLanguage(strtolower($tag[0]));
        $region = '';
        if (isset($tag[1])) {
            $region = self::getRegion(strtoupper($tag[1]));
        }
        return array(
            $language,
            $region
        );
    }