public function getRegularLangName($lang = NULL) {
        if (isset($this->_data['env']['APP_LANG_NAME'])) {
            return $this->_data['env']['APP_LANG_NAME'];
        }

        if (is_null($lang))
            $lang = Yii::$app->language;
        $this->_data['env']['ENABLED_LANGS'] = str_replace("-", "_", strtolower($lang));

        return $this->_data['env']['ENABLED_LANGS'];
    }