daggerhart · September 22, 2021 10:30 · daggerhart · Dec 30, 2015 · vladcosorg · Dec 8, 2016
diff --git a/custom-menu-items.php b/custom-menu-items.php
 <?php

 /*
 * Note! This is no longer updated here in the Gist. It has been moved to a repo.
 *
 * @link https://github.com/daggerhart/wp-custom-menu-items
 */

 /**
 * Class custom_menu_items
 *
 * This class is for creating and managing dynamic menu items in a WordPress
 * menu.
 */
 class custom_menu_items {
 	/**
 	 * Track that hooks have been registered w/ WP
 	 * @var bool
 	 */
 	protected $has_registered = false;

 	/**
 	 * Internal list of menus affected
 	 * @var array
 	 */
 	public $menus = array();

 	/**
 	 * Internal list of new menu items
 	 * @var array
 	 */
 	public $menu_items = array();

 	private function __construct(){}
 	private function __wakeup() {}
 	private function __clone() {}

 	/**
 	 * Singleton
 	 *
 	 * @return \custom_menu_items
 	 */
 	static public function get_instance(){
 		static $instance = null;

 		if ( is_null( $instance ) ){
 			$instance = new self;
 		}

 		$instance->register();
 		return $instance;
 	}

 	/**
 	 * Hook up plugin with WP
 	 */
 	private function register(){
 		if ( ! is_admin() && ! $this->has_registered ){
 			$this->has_registered = true;

 			add_filter( 'wp_get_nav_menu_items', array( $this, 'wp_get_nav_menu_items' ), 20, 2 );
 			add_filter( 'wp_get_nav_menu_object', array( $this, 'wp_get_nav_menu_object' ), 20, 2 );
 		}
 	}

 	/**
 	 * Update the menu items count when building the menu
 	 *
 	 * @param $menu_obj
 	 * @param $menu
 	 *
 	 * @return mixed
 	 */
 	function wp_get_nav_menu_object( $menu_obj, $menu ){
 		if ( is_a( $menu_obj, 'WP_Term' ) && isset( $this->menus[ $menu_obj->slug ] ) ){
 			$menu_obj->count += $this->count_menu_items( $menu_obj->slug );
 		}
 		return $menu_obj;
 	}

 	/**
 	 * Get the menu items from WP and add our new ones
 	 *
 	 * @param $items
 	 * @param $menu
 	 *
 	 * @return mixed
 	 */
 	function wp_get_nav_menu_items( $items, $menu ){
 		if ( isset( $this->menus[ $menu->slug ] ) ) {
 			$new_items = $this->get_menu_items( $menu->slug );

 			if ( ! empty( $new_items ) ) {
 				foreach ( $new_items as $new_item ) {
 					$items[] = $this->make_item_obj( $new_item );
 				}
 			}

 			$items = $this->fix_menu_orders( $items );
 		}

 		return $items;
 	}

 	/**
 	 * Entry point.
 	 * Add a new menu item to the list of custom menu items
 	 *
 	 * @param $menu_slug
 	 * @param $title
 	 * @param $url
 	 * @param $order
 	 * @param $parent
 	 * @param null $ID
 	 */
 	static public function add_item( $menu_slug, $title, $url, $order = 0, $parent = 0, $ID = null, $classes = array() ){
 		$instance = custom_menu_items::get_instance();
 		$instance->menus[ $menu_slug ] = $menu_slug;
 		$instance->menu_items[] = array(
 			'menu'    => $menu_slug,
 			'title'   => $title,
 			'url'     => $url,
 			'order'   => $order,
 			'parent'  => $parent,
 			'ID'      => $ID,
 			'classes' => $classes,
 		);
 	}

 	/**
 	 * Add a WP_Post or WP_Term to the menu using the object ID.
 	 *
 	 * @param $menu_slug
 	 * @param $object_ID
 	 * @param string $object_type
 	 * @param $order
 	 * @param $parent
 	 * @param null $ID
 	 */
 	static public function add_object( $menu_slug, $object_ID, $object_type = 'post', $order = 0, $parent = 0, $ID = NULL, $classes = array() ) {
 		$instance = custom_menu_items::get_instance();
 		$instance->menus[ $menu_slug ] = $menu_slug;

 		if ($object_type == 'post' && $object = get_post( $object_ID ) ) {
 			$instance->menu_items[] = array(
 				'menu'        => $menu_slug,
 				'order'       => $order,
 				'parent'      => $parent,
 				'post_parent' => $object->post_parent,
 				'title'       => get_the_title($object),
 				'url'         => get_permalink($object),
 				'ID'          => $ID,
 				'type'        => 'post_type',
 				'object'      => get_post_type($object),
 				'object_id'   => $object_ID,
 				'classes'     => $classes,
 			);
 		}
 		else if ($object_type == 'term') {
 			global $wpdb;
 			$sql = "SELECT t.*, tt.taxonomy, tt.parent FROM {$wpdb->terms} as t LEFT JOIN {$wpdb->term_taxonomy} as tt on tt.term_id = t.term_id WHERE t.term_id = %d";
 			$object = $wpdb->get_row($wpdb->prepare($sql, $object_ID));

 			if ( $object ) {
 				$instance->menu_items[] = $tmp = array(
 					'menu'        => $menu_slug,
 					'order'       => $order,
 					'parent'      => $parent,
 					'post_parent' => $object->parent,
 					'title'       => $object->name,
 					'url'         => get_term_link((int)$object->term_id, $object->taxonomy),
 					'ID'          => $ID,
 					'type'        => 'taxonomy',
 					'object'      => $object->taxonomy,
 					'object_id'   => $object_ID,
 					'classes'     => $classes,
 				);
 			}
 		}
 	}

 	/**
 	 * Get an array of new menu items for a specific menu slug
 	 *
 	 * @param $menu_slug
 	 *
 	 * @return array
 	 */
 	private function get_menu_items( $menu_slug ){
 		$items = array();

 		if ( isset( $this->menus[ $menu_slug ] ) ) {
 			$items = array_filter( $this->menu_items, function ( $item ) use ( $menu_slug ) {
 				return $item['menu'] == $menu_slug;
 			} );
 		}
 		return $items;
 	}

 	/**
 	 * Count the number of new menu items we are adding to an individual menu
 	 *
 	 * @param $menu_slug
 	 *
 	 * @return int
 	 */
 	private function count_menu_items( $menu_slug ){
 		if ( ! isset( $this->menus[ $menu_slug ] ) ) {
 			return 0;
 		}

 		$items = $this->get_menu_items( $menu_slug );

 		return count( $items );
 	}

 	/**
 	 * Helper to create item IDs
 	 *
 	 * @param $item
 	 *
 	 * @return int
 	 */
 	private function make_item_ID( $item ){
 		return 1000000 + $item['order'] + $item['parent'];
 	}

 	/**
 	 * Make a stored item array into a menu item object
 	 *
 	 * @param array $item
 	 *
 	 * @return mixed
 	 */
 	private function make_item_obj( $item ) {
 		// generic object made to look like a post object
 		$item_obj                   = new stdClass();
 		$item_obj->ID               = ( $item['ID'] ) ? $item['ID'] : $this->make_item_ID( $item );
 		$item_obj->title            = $item['title'];
 		$item_obj->url              = $item['url'];
 		$item_obj->menu_order       = $item['order'];
 		$item_obj->menu_item_parent = $item['parent'];
 		$item_obj->post_parent      = !empty( $item['post_parent'] ) ? $item['post_parent'] : '';

 		// menu specific properties
 		$item_obj->db_id            = $item_obj->ID;
 		$item_obj->type             = !empty( $item['type'] ) ? $item['type'] : '';
 		$item_obj->object           = !empty( $item['object'] ) ? $item['object'] : '';
 		$item_obj->object_id        = !empty( $item['object_id'] ) ? $item['object_id'] : '';

 		// output attributes
 		$item_obj->classes          = $item['classes'];
 		$item_obj->target           = '';
 		$item_obj->attr_title       = '';
 		$item_obj->description      = '';
 		$item_obj->xfn              = '';
 		$item_obj->status           = '';

 		return $item_obj;
 	}

 	/**
 	 * Menu items with the same menu_order property cause a conflict. This
 	 * method attempts to provide each menu item with its own unique order value.
 	 * Thanks @codepuncher
 	 *
 	 * @param $items
 	 *
 	 * @return mixed
 	 */
 	private function fix_menu_orders( $items ){
 		$items = wp_list_sort( $items, 'menu_order' );

 		for( $i = 0; $i < count( $items ); $i++ ){
 			$items[ $i ]->menu_order = $i;
 		}

 		return $items;
 	}
 }