WP_Classic_To_Block_Menu_Converter

14class WP_Classic_To_Block_Menu_Converter {15 16	/**17	 * Converts a Classic Menu to blocks.18	 *19	 * @since 6.3.020	 *21	 * @param WP_Term $menu The Menu term object of the menu to convert.22	 * @return string|WP_Error The serialized and normalized parsed blocks on success,23	 *                         an empty string when there are no menus to convert,24	 *                         or WP_Error on invalid menu.25	 */26	public static function convert( $menu ) {27 28		if ( ! is_nav_menu( $menu ) ) {29			return new WP_Error(30				'invalid_menu',31				__( 'The menu provided is not a valid menu.' )32			);33		}34 35		$menu_items = wp_get_nav_menu_items( $menu->term_id, array( 'update_post_term_cache' => false ) );36 37		if ( empty( $menu_items ) ) {38			return '';39		}40 41		// Set up the $menu_item variables.42		// Adds the class property classes for the current context, if applicable.43		_wp_menu_item_classes_by_context( $menu_items );44 45		$menu_items_by_parent_id = static::group_by_parent_id( $menu_items );46 47		$first_menu_item = $menu_items_by_parent_id[0] ?? array();48 49		$inner_blocks = static::to_blocks(50			$first_menu_item,51			$menu_items_by_parent_id52		);53 54		return serialize_blocks( $inner_blocks );55	}56 57	/**58	 * Returns an array of menu items grouped by the id of the parent menu item.59	 *60	 * @since 6.3.061	 *62	 * @param array $menu_items An array of menu items.63	 * @return array64	 */65	private static function group_by_parent_id( $menu_items ) {66		$menu_items_by_parent_id = array();67 68		foreach ( $menu_items as $menu_item ) {69			$menu_items_by_parent_id[ $menu_item->menu_item_parent ][] = $menu_item;70		}71 72		return $menu_items_by_parent_id;73	}74 75	/**76	 * Turns menu item data into a nested array of parsed blocks77	 *78	 * @since 6.3.079	 *80	 * @param array $menu_items              An array of menu items that represent81	 *                                       an individual level of a menu.82	 * @param array $menu_items_by_parent_id An array keyed by the id of the83	 *                                       parent menu where each element is an84	 *                                       array of menu items that belong to85	 *                                       that parent.86	 * @return array An array of parsed block data.87	 */88	private static function to_blocks( $menu_items, $menu_items_by_parent_id ) {89 90		if ( empty( $menu_items ) ) {91			return array();92		}93