public function add()
    {
        if (!$this->request->isAll(['ajax', 'post'])) {
            throw new MethodNotAllowedException();
        }

        $model = $this->request->data('model');
        $foreignKey = (int)$this->request->data('foreign_key');
        $languageId = Wasabi::contentLanguage()->id;
        $url = $this->_formatUrl($this->request->data('url'));
        $routeType = (int)$this->request->data('route_type');
        $element = $this->request->data('element');

        $routeData = [
            'url' => $url,
            'model' => $model,
            'foreign_key' => $foreignKey,
            'language_id' => $languageId,
        ];

        $route = $this->_addRoute($routeType, $routeData);

        $this->_render($route, $element);
    }