private function get_layout_id($post_id, $post_type)
 {
     global $wpddlayout, $pagenow;
     if ($pagenow == 'post-new.php') {
         $layout = $wpddlayout->post_types_manager->get_layout_to_type_object($post_type);
         if (null === $layout) {
             return null;
         }
         return $layout->layout_id;
     } else {
         $layout_slug = self::page_has_layout($post_id);
         if ($layout_slug === false) {
             return null;
         }
         return WPDD_Layouts::get_layout_id_by_slug($layout_slug);
     }
 }