public function actionDelete()
 {
     $itemId = yii::$app->request->post('item_id');
     $variantId = yii::$app->request->post('variant_id');
     $filterId = yii::$app->request->post('filter_id');
     if ($value = FilterValue::find()->where(['item_id' => $itemId, 'variant_id' => $variantId])->one()) {
         $value->delete();
     } else {
         FilterValue::deleteAll(['item_id' => $itemId, 'filter_id' => $filterId]);
     }
     return json_encode(['result' => 'success']);
 }