public function prepare($items = null)
    {
        $items->each(function ($item) {
            $item->items = collect();
            if ($item->has_categories) {
                $item->items = $this->prepare(ProjectCategories::allForMenu($item->page->uri()));
            }
            $item->href = $this->setHref($item);
            $item->class = $this->setClass($item);
        });

        return $items;
    }