public function registerAssets()
    {
        // make sure core hasn't been registered previously

        $dirs = array('css', 'js');
        foreach ($this->assets as $key => $files) {
            if (in_array($key, $dirs)) {
                $files = is_array($files) ? $files : array($files);
                foreach ($files as $file) {
                    $filePath = Foundation::getAssetsPath() . DIRECTORY_SEPARATOR . $key . DIRECTORY_SEPARATOR . $file;
                    if (file_exists($filePath) && is_file($filePath)) {
                        $method = strcasecmp($key, 'css') === 0 ? 'registerCssFile' : 'registerScriptFile';
                        call_user_func(
                            array(\Yii::app()->clientScript, "$method"),
                            Foundation::getAssetsUrl() . "/$key/$file"
                        );
                    }
                }
            }
        }

    }