public function addMetabox()
    {
        $fields = $this->getModel()->getFields();

        // Add meta box
        add_meta_box(
            $this->getModel()->getId(),
            $this->getModel()->getTitle(),
            [$this, 'callback'],
            $this->getModel()->getSlug(),
            $this->getModel()->getContext(),
            $this->getModel()->getPriority(),
            $fields
        );

        // Render assets
        Render::assets(['post.php', 'post-new.php'], $fields);
    }