WordPress menu on the fly

Wordpress menu on the fly

<?php
  // it needs to be attached to a hook like save_post or something similar
  $pages = get_posts(
      array(
          'post_type'      => 'page',
          'posts_per_page' => - 1
      )
  );
  $projects = get_posts(
      array(
          'post_type'      => 'project',
          'posts_per_page' => - 1
      )
  );
  $menu_name = 'ms-main-menu';
  $menu_exists = wp_get_nav_menu_object( $menu_name );
  if ( $menu_exists ) {
      wp_delete_nav_menu( $menu_name );
  }
  $menu_id = wp_create_nav_menu( $menu_name );
  $menu = get_term_by( 'name', $menu_name, 'nav_menu' );
  // Set up default page items
  if ( ! empty( $pages ) ) {
      foreach ( $pages as $page ) {
          $itemData =  array(
              'menu-item-object-id' => $page->ID,
              'menu-item-object' => $page->post_type,
              'menu-item-type' => 'post_type',
              'menu-item-status' => 'publish'
          );
          wp_update_nav_menu_item($menu->term_id, 0, $itemData);
      }
  }
  // Set up default project items
  if ( ! empty( $projects ) ) {
      foreach ( $projects as $project ) {
          $itemData =  array(
              'menu-item-object-id' => $project->ID,
              'menu-item-object' => $project->post_type,
              'menu-item-type' => 'post_type',
              'menu-item-status' => 'publish'
          );
          wp_update_nav_menu_item($menu->term_id, 0, $itemData);
      }
  }
  $locations = get_theme_mod('nav_menu_locations');
  $locations['main'] = $menu->term_id;
  set_theme_mod( 'nav_menu_locations', $locations );
?>