public function deletePhoto($model, $parentRelation = null)
    {
        $thumbs = $this->options['photo']['thumbnails'];
        $id = is_null($parentRelation) ? $model->id : $model->$parentRelation->id;
        $path = $this->options['photo']['path'] . "/{$id}";
        // delete original
        $this->delete($path . "/original/{$model->photo}");
        // thumbnails delete
        foreach($thumbs as $thumb => $size){
            $this->delete($path . "/thumbnails/{$thumb}_{$model->photo}");
        }
    }