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   1  /**
   2   * @output wp-admin/js/customize-nav-menus.js
   3   */
   4  
   5  /* global _wpCustomizeNavMenusSettings, wpNavMenu, console */
   6  ( function( api, wp, $ ) {
   7      'use strict';
   8  
   9      /**
  10       * Set up wpNavMenu for drag and drop.
  11       */
  12      wpNavMenu.originalInit = wpNavMenu.init;
  13      wpNavMenu.options.menuItemDepthPerLevel = 20;
  14      wpNavMenu.options.sortableItems         = '> .customize-control-nav_menu_item';
  15      wpNavMenu.options.targetTolerance       = 10;
  16      wpNavMenu.init = function() {
  17          this.jQueryExtensions();
  18      };
  19  
  20      /**
  21       * @namespace wp.customize.Menus
  22       */
  23      api.Menus = api.Menus || {};
  24  
  25      // Link settings.
  26      api.Menus.data = {
  27          itemTypes: [],
  28          l10n: {},
  29          settingTransport: 'refresh',
  30          phpIntMax: 0,
  31          defaultSettingValues: {
  32              nav_menu: {},
  33              nav_menu_item: {}
  34          },
  35          locationSlugMappedToName: {}
  36      };
  37      if ( 'undefined' !== typeof _wpCustomizeNavMenusSettings ) {
  38          $.extend( api.Menus.data, _wpCustomizeNavMenusSettings );
  39      }
  40  
  41      /**
  42       * Newly-created Nav Menus and Nav Menu Items have negative integer IDs which
  43       * serve as placeholders until Save & Publish happens.
  44       *
  45       * @alias wp.customize.Menus.generatePlaceholderAutoIncrementId
  46       *
  47       * @return {number}
  48       */
  49      api.Menus.generatePlaceholderAutoIncrementId = function() {
  50          return -Math.ceil( api.Menus.data.phpIntMax * Math.random() );
  51      };
  52  
  53      /**
  54       * wp.customize.Menus.AvailableItemModel
  55       *
  56       * A single available menu item model. See PHP's WP_Customize_Nav_Menu_Item_Setting class.
  57       *
  58       * @class    wp.customize.Menus.AvailableItemModel
  59       * @augments Backbone.Model
  60       */
  61      api.Menus.AvailableItemModel = Backbone.Model.extend( $.extend(
  62          {
  63              id: null // This is only used by Backbone.
  64          },
  65          api.Menus.data.defaultSettingValues.nav_menu_item
  66      ) );
  67  
  68      /**
  69       * wp.customize.Menus.AvailableItemCollection
  70       *
  71       * Collection for available menu item models.
  72       *
  73       * @class    wp.customize.Menus.AvailableItemCollection
  74       * @augments Backbone.Collection
  75       */
  76      api.Menus.AvailableItemCollection = Backbone.Collection.extend(/** @lends wp.customize.Menus.AvailableItemCollection.prototype */{
  77          model: api.Menus.AvailableItemModel,
  78  
  79          sort_key: 'order',
  80  
  81          comparator: function( item ) {
  82              return -item.get( this.sort_key );
  83          },
  84  
  85          sortByField: function( fieldName ) {
  86              this.sort_key = fieldName;
  87              this.sort();
  88          }
  89      });
  90      api.Menus.availableMenuItems = new api.Menus.AvailableItemCollection( api.Menus.data.availableMenuItems );
  91  
  92      /**
  93       * Insert a new `auto-draft` post.
  94       *
  95       * @since 4.7.0
  96       * @alias wp.customize.Menus.insertAutoDraftPost
  97       *
  98       * @param {Object} params - Parameters for the draft post to create.
  99       * @param {string} params.post_type - Post type to add.
 100       * @param {string} params.post_title - Post title to use.
 101       * @return {jQuery.promise} Promise resolved with the added post.
 102       */
 103      api.Menus.insertAutoDraftPost = function insertAutoDraftPost( params ) {
 104          var request, deferred = $.Deferred();
 105  
 106          request = wp.ajax.post( 'customize-nav-menus-insert-auto-draft', {
 107              'customize-menus-nonce': api.settings.nonce['customize-menus'],
 108              'wp_customize': 'on',
 109              'customize_changeset_uuid': api.settings.changeset.uuid,
 110              'params': params
 111          } );
 112  
 113          request.done( function( response ) {
 114              if ( response.post_id ) {
 115                  api( 'nav_menus_created_posts' ).set(
 116                      api( 'nav_menus_created_posts' ).get().concat( [ response.post_id ] )
 117                  );
 118  
 119                  if ( 'page' === params.post_type ) {
 120  
 121                      // Activate static front page controls as this could be the first page created.
 122                      if ( api.section.has( 'static_front_page' ) ) {
 123                          api.section( 'static_front_page' ).activate();
 124                      }
 125  
 126                      // Add new page to dropdown-pages controls.
 127                      api.control.each( function( control ) {
 128                          var select;
 129                          if ( 'dropdown-pages' === control.params.type ) {
 130                              select = control.container.find( 'select[name^="_customize-dropdown-pages-"]' );
 131                              select.append( new Option( params.post_title, response.post_id ) );
 132                          }
 133                      } );
 134                  }
 135                  deferred.resolve( response );
 136              }
 137          } );
 138  
 139          request.fail( function( response ) {
 140              var error = response || '';
 141  
 142              if ( 'undefined' !== typeof response.message ) {
 143                  error = response.message;
 144              }
 145  
 146              console.error( error );
 147              deferred.rejectWith( error );
 148          } );
 149  
 150          return deferred.promise();
 151      };
 152  
 153      api.Menus.AvailableMenuItemsPanelView = wp.Backbone.View.extend(/** @lends wp.customize.Menus.AvailableMenuItemsPanelView.prototype */{
 154  
 155          el: '#available-menu-items',
 156  
 157          events: {
 158              'input #menu-items-search': 'debounceSearch',
 159              'focus .menu-item-tpl': 'focus',
 160              'click .menu-item-tpl': '_submit',
 161              'click #custom-menu-item-submit': '_submitLink',
 162              'keypress #custom-menu-item-name': '_submitLink',
 163              'click .new-content-item .add-content': '_submitNew',
 164              'keypress .create-item-input': '_submitNew',
 165              'keydown': 'keyboardAccessible'
 166          },
 167  
 168          // Cache current selected menu item.
 169          selected: null,
 170  
 171          // Cache menu control that opened the panel.
 172          currentMenuControl: null,
 173          debounceSearch: null,
 174          $search: null,
 175          $clearResults: null,
 176          searchTerm: '',
 177          rendered: false,
 178          pages: {},
 179          sectionContent: '',
 180          loading: false,
 181          addingNew: false,
 182  
 183          /**
 184           * wp.customize.Menus.AvailableMenuItemsPanelView
 185           *
 186           * View class for the available menu items panel.
 187           *
 188           * @constructs wp.customize.Menus.AvailableMenuItemsPanelView
 189           * @augments   wp.Backbone.View
 190           */
 191          initialize: function() {
 192              var self = this;
 193  
 194              if ( ! api.panel.has( 'nav_menus' ) ) {
 195                  return;
 196              }
 197  
 198              this.$search = $( '#menu-items-search' );
 199              this.$clearResults = this.$el.find( '.clear-results' );
 200              this.sectionContent = this.$el.find( '.available-menu-items-list' );
 201  
 202              this.debounceSearch = _.debounce( self.search, 500 );
 203  
 204              _.bindAll( this, 'close' );
 205  
 206              /*
 207               * If the available menu items panel is open and the customize controls
 208               * are interacted with (other than an item being deleted), then close
 209               * the available menu items panel. Also close on back button click.
 210               */
 211              $( '#customize-controls, .customize-section-back' ).on( 'click keydown', function( e ) {
 212                  var isDeleteBtn = $( e.target ).is( '.item-delete, .item-delete *' ),
 213                      isAddNewBtn = $( e.target ).is( '.add-new-menu-item, .add-new-menu-item *' );
 214                  if ( $( 'body' ).hasClass( 'adding-menu-items' ) && ! isDeleteBtn && ! isAddNewBtn ) {
 215                      self.close();
 216                  }
 217              } );
 218  
 219              // Clear the search results and trigger an `input` event to fire a new search.
 220              this.$clearResults.on( 'click', function() {
 221                  self.$search.val( '' ).trigger( 'focus' ).trigger( 'input' );
 222              } );
 223  
 224              this.$el.on( 'input', '#custom-menu-item-name.invalid, #custom-menu-item-url.invalid', function() {
 225                  $( this ).removeClass( 'invalid' );
 226              });
 227  
 228              // Load available items if it looks like we'll need them.
 229              api.panel( 'nav_menus' ).container.on( 'expanded', function() {
 230                  if ( ! self.rendered ) {
 231                      self.initList();
 232                      self.rendered = true;
 233                  }
 234              });
 235  
 236              // Load more items.
 237              this.sectionContent.on( 'scroll', function() {
 238                  var totalHeight = self.$el.find( '.accordion-section.open .available-menu-items-list' ).prop( 'scrollHeight' ),
 239                      visibleHeight = self.$el.find( '.accordion-section.open' ).height();
 240  
 241                  if ( ! self.loading && $( this ).scrollTop() > 3 / 4 * totalHeight - visibleHeight ) {
 242                      var type = $( this ).data( 'type' ),
 243                          object = $( this ).data( 'object' );
 244  
 245                      if ( 'search' === type ) {
 246                          if ( self.searchTerm ) {
 247                              self.doSearch( self.pages.search );
 248                          }
 249                      } else {
 250                          self.loadItems( [
 251                              { type: type, object: object }
 252                          ] );
 253                      }
 254                  }
 255              });
 256  
 257              // Close the panel if the URL in the preview changes.
 258              api.previewer.bind( 'url', this.close );
 259  
 260              self.delegateEvents();
 261          },
 262  
 263          // Search input change handler.
 264          search: function( event ) {
 265              var $searchSection = $( '#available-menu-items-search' ),
 266                  $otherSections = $( '#available-menu-items .accordion-section' ).not( $searchSection );
 267  
 268              if ( ! event ) {
 269                  return;
 270              }
 271  
 272              if ( this.searchTerm === event.target.value ) {
 273                  return;
 274              }
 275  
 276              if ( '' !== event.target.value && ! $searchSection.hasClass( 'open' ) ) {
 277                  $otherSections.fadeOut( 100 );
 278                  $searchSection.find( '.accordion-section-content' ).slideDown( 'fast' );
 279                  $searchSection.addClass( 'open' );
 280                  this.$clearResults.addClass( 'is-visible' );
 281              } else if ( '' === event.target.value ) {
 282                  $searchSection.removeClass( 'open' );
 283                  $otherSections.show();
 284                  this.$clearResults.removeClass( 'is-visible' );
 285              }
 286  
 287              this.searchTerm = event.target.value;
 288              this.pages.search = 1;
 289              this.doSearch( 1 );
 290          },
 291  
 292          // Get search results.
 293          doSearch: function( page ) {
 294              var self = this, params,
 295                  $section = $( '#available-menu-items-search' ),
 296                  $content = $section.find( '.accordion-section-content' ),
 297                  itemTemplate = wp.template( 'available-menu-item' );
 298  
 299              if ( self.currentRequest ) {
 300                  self.currentRequest.abort();
 301              }
 302  
 303              if ( page < 0 ) {
 304                  return;
 305              } else if ( page > 1 ) {
 306                  $section.addClass( 'loading-more' );
 307                  $content.attr( 'aria-busy', 'true' );
 308                  wp.a11y.speak( api.Menus.data.l10n.itemsLoadingMore );
 309              } else if ( '' === self.searchTerm ) {
 310                  $content.html( '' );
 311                  wp.a11y.speak( '' );
 312                  return;
 313              }
 314  
 315              $section.addClass( 'loading' );
 316              self.loading = true;
 317  
 318              params = api.previewer.query( { excludeCustomizedSaved: true } );
 319              _.extend( params, {
 320                  'customize-menus-nonce': api.settings.nonce['customize-menus'],
 321                  'wp_customize': 'on',
 322                  'search': self.searchTerm,
 323                  'page': page
 324              } );
 325  
 326              self.currentRequest = wp.ajax.post( 'search-available-menu-items-customizer', params );
 327  
 328              self.currentRequest.done(function( data ) {
 329                  var items;
 330                  if ( 1 === page ) {
 331                      // Clear previous results as it's a new search.
 332                      $content.empty();
 333                  }
 334                  $section.removeClass( 'loading loading-more' );
 335                  $content.attr( 'aria-busy', 'false' );
 336                  $section.addClass( 'open' );
 337                  self.loading = false;
 338                  items = new api.Menus.AvailableItemCollection( data.items );
 339                  self.collection.add( items.models );
 340                  items.each( function( menuItem ) {
 341                      $content.append( itemTemplate( menuItem.attributes ) );
 342                  } );
 343                  if ( 20 > items.length ) {
 344                      self.pages.search = -1; // Up to 20 posts and 20 terms in results, if <20, no more results for either.
 345                  } else {
 346                      self.pages.search = self.pages.search + 1;
 347                  }
 348                  if ( items && page > 1 ) {
 349                      wp.a11y.speak( api.Menus.data.l10n.itemsFoundMore.replace( '%d', items.length ) );
 350                  } else if ( items && page === 1 ) {
 351                      wp.a11y.speak( api.Menus.data.l10n.itemsFound.replace( '%d', items.length ) );
 352                  }
 353              });
 354  
 355              self.currentRequest.fail(function( data ) {
 356                  // data.message may be undefined, for example when typing slow and the request is aborted.
 357                  if ( data.message ) {
 358                      $content.empty().append( $( '<li class="nothing-found"></li>' ).text( data.message ) );
 359                      wp.a11y.speak( data.message );
 360                  }
 361                  self.pages.search = -1;
 362              });
 363  
 364              self.currentRequest.always(function() {
 365                  $section.removeClass( 'loading loading-more' );
 366                  $content.attr( 'aria-busy', 'false' );
 367                  self.loading = false;
 368                  self.currentRequest = null;
 369              });
 370          },
 371  
 372          // Render the individual items.
 373          initList: function() {
 374              var self = this;
 375  
 376              // Render the template for each item by type.
 377              _.each( api.Menus.data.itemTypes, function( itemType ) {
 378                  self.pages[ itemType.type + ':' + itemType.object ] = 0;
 379              } );
 380              self.loadItems( api.Menus.data.itemTypes );
 381          },
 382  
 383          /**
 384           * Load available nav menu items.
 385           *
 386           * @since 4.3.0
 387           * @since 4.7.0 Changed function signature to take list of item types instead of single type/object.
 388           * @access private
 389           *
 390           * @param {Array.<Object>} itemTypes List of objects containing type and key.
 391           * @param {string} deprecated Formerly the object parameter.
 392           * @return {void}
 393           */
 394          loadItems: function( itemTypes, deprecated ) {
 395              var self = this, _itemTypes, requestItemTypes = [], params, request, itemTemplate, availableMenuItemContainers = {};
 396              itemTemplate = wp.template( 'available-menu-item' );
 397  
 398              if ( _.isString( itemTypes ) && _.isString( deprecated ) ) {
 399                  _itemTypes = [ { type: itemTypes, object: deprecated } ];
 400              } else {
 401                  _itemTypes = itemTypes;
 402              }
 403  
 404              _.each( _itemTypes, function( itemType ) {
 405                  var container, name = itemType.type + ':' + itemType.object;
 406                  if ( -1 === self.pages[ name ] ) {
 407                      return; // Skip types for which there are no more results.
 408                  }
 409                  container = $( '#available-menu-items-' + itemType.type + '-' + itemType.object );
 410                  container.find( '.accordion-section-title' ).addClass( 'loading' );
 411                  availableMenuItemContainers[ name ] = container;
 412  
 413                  requestItemTypes.push( {
 414                      object: itemType.object,
 415                      type: itemType.type,
 416                      page: self.pages[ name ]
 417                  } );
 418              } );
 419  
 420              if ( 0 === requestItemTypes.length ) {
 421                  return;
 422              }
 423  
 424              self.loading = true;
 425  
 426              params = api.previewer.query( { excludeCustomizedSaved: true } );
 427              _.extend( params, {
 428                  'customize-menus-nonce': api.settings.nonce['customize-menus'],
 429                  'wp_customize': 'on',
 430                  'item_types': requestItemTypes
 431              } );
 432  
 433              request = wp.ajax.post( 'load-available-menu-items-customizer', params );
 434  
 435              request.done(function( data ) {
 436                  var typeInner;
 437                  _.each( data.items, function( typeItems, name ) {
 438                      if ( 0 === typeItems.length ) {
 439                          if ( 0 === self.pages[ name ] ) {
 440                              availableMenuItemContainers[ name ].find( '.accordion-section-title' )
 441                                  .addClass( 'cannot-expand' )
 442                                  .removeClass( 'loading' )
 443                                  .find( '.accordion-section-title > button' )
 444                                  .prop( 'tabIndex', -1 );
 445                          }
 446                          self.pages[ name ] = -1;
 447                          return;
 448                      } else if ( ( 'post_type:page' === name ) && ( ! availableMenuItemContainers[ name ].hasClass( 'open' ) ) ) {
 449                          availableMenuItemContainers[ name ].find( '.accordion-section-title > button' ).trigger( 'click' );
 450                      }
 451                      typeItems = new api.Menus.AvailableItemCollection( typeItems ); // @todo Why is this collection created and then thrown away?
 452                      self.collection.add( typeItems.models );
 453                      typeInner = availableMenuItemContainers[ name ].find( '.available-menu-items-list' );
 454                      typeItems.each( function( menuItem ) {
 455                          typeInner.append( itemTemplate( menuItem.attributes ) );
 456                      } );
 457                      self.pages[ name ] += 1;
 458                  });
 459              });
 460              request.fail(function( data ) {
 461                  if ( typeof console !== 'undefined' && console.error ) {
 462                      console.error( data );
 463                  }
 464              });
 465              request.always(function() {
 466                  _.each( availableMenuItemContainers, function( container ) {
 467                      container.find( '.accordion-section-title' ).removeClass( 'loading' );
 468                  } );
 469                  self.loading = false;
 470              });
 471          },
 472  
 473          // Adjust the height of each section of items to fit the screen.
 474          itemSectionHeight: function() {
 475              var sections, lists, totalHeight, accordionHeight, diff;
 476              totalHeight = window.innerHeight;
 477              sections = this.$el.find( '.accordion-section:not( #available-menu-items-search ) .accordion-section-content' );
 478              lists = this.$el.find( '.accordion-section:not( #available-menu-items-search ) .available-menu-items-list:not(":only-child")' );
 479              accordionHeight =  46 * ( 1 + sections.length ) + 14; // Magic numbers.
 480              diff = totalHeight - accordionHeight;
 481              if ( 120 < diff && 290 > diff ) {
 482                  sections.css( 'max-height', diff );
 483                  lists.css( 'max-height', ( diff - 60 ) );
 484              }
 485          },
 486  
 487          // Highlights a menu item.
 488          select: function( menuitemTpl ) {
 489              this.selected = $( menuitemTpl );
 490              this.selected.siblings( '.menu-item-tpl' ).removeClass( 'selected' );
 491              this.selected.addClass( 'selected' );
 492          },
 493  
 494          // Highlights a menu item on focus.
 495          focus: function( event ) {
 496              this.select( $( event.currentTarget ) );
 497          },
 498  
 499          // Submit handler for keypress and click on menu item.
 500          _submit: function( event ) {
 501              // Only proceed with keypress if it is Enter or Spacebar.
 502              if ( 'keypress' === event.type && ( 13 !== event.which && 32 !== event.which ) ) {
 503                  return;
 504              }
 505  
 506              this.submit( $( event.currentTarget ) );
 507          },
 508  
 509          // Adds a selected menu item to the menu.
 510          submit: function( menuitemTpl ) {
 511              var menuitemId, menu_item;
 512  
 513              if ( ! menuitemTpl ) {
 514                  menuitemTpl = this.selected;
 515              }
 516  
 517              if ( ! menuitemTpl || ! this.currentMenuControl ) {
 518                  return;
 519              }
 520  
 521              this.select( menuitemTpl );
 522  
 523              menuitemId = $( this.selected ).data( 'menu-item-id' );
 524              menu_item = this.collection.findWhere( { id: menuitemId } );
 525              if ( ! menu_item ) {
 526                  return;
 527              }
 528  
 529              this.currentMenuControl.addItemToMenu( menu_item.attributes );
 530  
 531              $( menuitemTpl ).find( '.menu-item-handle' ).addClass( 'item-added' );
 532          },
 533  
 534          // Submit handler for keypress and click on custom menu item.
 535          _submitLink: function( event ) {
 536              // Only proceed with keypress if it is Enter.
 537              if ( 'keypress' === event.type && 13 !== event.which ) {
 538                  return;
 539              }
 540  
 541              this.submitLink();
 542          },
 543  
 544          // Adds the custom menu item to the menu.
 545          submitLink: function() {
 546              var menuItem,
 547                  itemName = $( '#custom-menu-item-name' ),
 548                  itemUrl = $( '#custom-menu-item-url' ),
 549                  url = itemUrl.val().trim(),
 550                  urlRegex;
 551  
 552              if ( ! this.currentMenuControl ) {
 553                  return;
 554              }
 555  
 556              /*
 557               * Allow URLs including:
 558               * - http://example.com/
 559               * - //example.com
 560               * - /directory/
 561               * - ?query-param
 562               * - #target
 563               * - mailto:foo@example.com
 564               *
 565               * Any further validation will be handled on the server when the setting is attempted to be saved,
 566               * so this pattern does not need to be complete.
 567               */
 568              urlRegex = /^((\w+:)?\/\/\w.*|\w+:(?!\/\/$)|\/|\?|#)/;
 569  
 570              if ( '' === itemName.val() ) {
 571                  itemName.addClass( 'invalid' );
 572                  return;
 573              } else if ( ! urlRegex.test( url ) ) {
 574                  itemUrl.addClass( 'invalid' );
 575                  return;
 576              }
 577  
 578              menuItem = {
 579                  'title': itemName.val(),
 580                  'url': url,
 581                  'type': 'custom',
 582                  'type_label': api.Menus.data.l10n.custom_label,
 583                  'object': 'custom'
 584              };
 585  
 586              this.currentMenuControl.addItemToMenu( menuItem );
 587  
 588              // Reset the custom link form.
 589              itemUrl.val( '' ).attr( 'placeholder', 'https://' );
 590              itemName.val( '' );
 591          },
 592  
 593          /**
 594           * Submit handler for keypress (enter) on field and click on button.
 595           *
 596           * @since 4.7.0
 597           * @private
 598           *
 599           * @param {jQuery.Event} event Event.
 600           * @return {void}
 601           */
 602          _submitNew: function( event ) {
 603              var container;
 604  
 605              // Only proceed with keypress if it is Enter.
 606              if ( 'keypress' === event.type && 13 !== event.which ) {
 607                  return;
 608              }
 609  
 610              if ( this.addingNew ) {
 611                  return;
 612              }
 613  
 614              container = $( event.target ).closest( '.accordion-section' );
 615  
 616              this.submitNew( container );
 617          },
 618  
 619          /**
 620           * Creates a new object and adds an associated menu item to the menu.
 621           *
 622           * @since 4.7.0
 623           * @private
 624           *
 625           * @param {jQuery} container
 626           * @return {void}
 627           */
 628          submitNew: function( container ) {
 629              var panel = this,
 630                  itemName = container.find( '.create-item-input' ),
 631                  title = itemName.val(),
 632                  dataContainer = container.find( '.available-menu-items-list' ),
 633                  itemType = dataContainer.data( 'type' ),
 634                  itemObject = dataContainer.data( 'object' ),
 635                  itemTypeLabel = dataContainer.data( 'type_label' ),
 636                  promise;
 637  
 638              if ( ! this.currentMenuControl ) {
 639                  return;
 640              }
 641  
 642              // Only posts are supported currently.
 643              if ( 'post_type' !== itemType ) {
 644                  return;
 645              }
 646  
 647              if ( '' === itemName.val().trim() ) {
 648                  itemName.addClass( 'invalid' );
 649                  itemName.focus();
 650                  return;
 651              } else {
 652                  itemName.removeClass( 'invalid' );
 653                  container.find( '.accordion-section-title' ).addClass( 'loading' );
 654              }
 655  
 656              panel.addingNew = true;
 657              itemName.attr( 'disabled', 'disabled' );
 658              promise = api.Menus.insertAutoDraftPost( {
 659                  post_title: title,
 660                  post_type: itemObject
 661              } );
 662              promise.done( function( data ) {
 663                  var availableItem, $content, itemElement;
 664                  availableItem = new api.Menus.AvailableItemModel( {
 665                      'id': 'post-' + data.post_id, // Used for available menu item Backbone models.
 666                      'title': itemName.val(),
 667                      'type': itemType,
 668                      'type_label': itemTypeLabel,
 669                      'object': itemObject,
 670                      'object_id': data.post_id,
 671                      'url': data.url
 672                  } );
 673  
 674                  // Add new item to menu.
 675                  panel.currentMenuControl.addItemToMenu( availableItem.attributes );
 676  
 677                  // Add the new item to the list of available items.
 678                  api.Menus.availableMenuItemsPanel.collection.add( availableItem );
 679                  $content = container.find( '.available-menu-items-list' );
 680                  itemElement = $( wp.template( 'available-menu-item' )( availableItem.attributes ) );
 681                  itemElement.find( '.menu-item-handle:first' ).addClass( 'item-added' );
 682                  $content.prepend( itemElement );
 683                  $content.scrollTop();
 684  
 685                  // Reset the create content form.
 686                  itemName.val( '' ).removeAttr( 'disabled' );
 687                  panel.addingNew = false;
 688                  container.find( '.accordion-section-title' ).removeClass( 'loading' );
 689              } );
 690          },
 691  
 692          // Opens the panel.
 693          open: function( menuControl ) {
 694              var panel = this, close;
 695  
 696              this.currentMenuControl = menuControl;
 697  
 698              this.itemSectionHeight();
 699  
 700              if ( api.section.has( 'publish_settings' ) ) {
 701                  api.section( 'publish_settings' ).collapse();
 702              }
 703  
 704              $( 'body' ).addClass( 'adding-menu-items' );
 705  
 706              close = function() {
 707                  panel.close();
 708                  $( this ).off( 'click', close );
 709              };
 710              $( '#customize-preview' ).on( 'click', close );
 711  
 712              // Collapse all controls.
 713              _( this.currentMenuControl.getMenuItemControls() ).each( function( control ) {
 714                  control.collapseForm();
 715              } );
 716  
 717              this.$el.find( '.selected' ).removeClass( 'selected' );
 718  
 719              this.$search.trigger( 'focus' );
 720          },
 721  
 722          // Closes the panel.
 723          close: function( options ) {
 724              options = options || {};
 725  
 726              if ( options.returnFocus && this.currentMenuControl ) {
 727                  this.currentMenuControl.container.find( '.add-new-menu-item' ).focus();
 728              }
 729  
 730              this.currentMenuControl = null;
 731              this.selected = null;
 732  
 733              $( 'body' ).removeClass( 'adding-menu-items' );
 734              $( '#available-menu-items .menu-item-handle.item-added' ).removeClass( 'item-added' );
 735  
 736              this.$search.val( '' ).trigger( 'input' );
 737          },
 738  
 739          // Add a few keyboard enhancements to the panel.
 740          keyboardAccessible: function( event ) {
 741              var isEnter = ( 13 === event.which ),
 742                  isEsc = ( 27 === event.which ),
 743                  isBackTab = ( 9 === event.which && event.shiftKey ),
 744                  isSearchFocused = $( event.target ).is( this.$search );
 745  
 746              // If enter pressed but nothing entered, don't do anything.
 747              if ( isEnter && ! this.$search.val() ) {
 748                  return;
 749              }
 750  
 751              if ( isSearchFocused && isBackTab ) {
 752                  this.currentMenuControl.container.find( '.add-new-menu-item' ).focus();
 753                  event.preventDefault(); // Avoid additional back-tab.
 754              } else if ( isEsc ) {
 755                  this.close( { returnFocus: true } );
 756              }
 757          }
 758      });
 759  
 760      /**
 761       * wp.customize.Menus.MenusPanel
 762       *
 763       * Customizer panel for menus. This is used only for screen options management.
 764       * Note that 'menus' must match the WP_Customize_Menu_Panel::$type.
 765       *
 766       * @class    wp.customize.Menus.MenusPanel
 767       * @augments wp.customize.Panel
 768       */
 769      api.Menus.MenusPanel = api.Panel.extend(/** @lends wp.customize.Menus.MenusPanel.prototype */{
 770  
 771          attachEvents: function() {
 772              api.Panel.prototype.attachEvents.call( this );
 773  
 774              var panel = this,
 775                  panelMeta = panel.container.find( '.panel-meta' ),
 776                  help = panelMeta.find( '.customize-help-toggle' ),
 777                  content = panelMeta.find( '.customize-panel-description' ),
 778                  options = $( '#screen-options-wrap' ),
 779                  button = panelMeta.find( '.customize-screen-options-toggle' );
 780              button.on( 'click keydown', function( event ) {
 781                  if ( api.utils.isKeydownButNotEnterEvent( event ) ) {
 782                      return;
 783                  }
 784                  event.preventDefault();
 785  
 786                  // Hide description.
 787                  if ( content.not( ':hidden' ) ) {
 788                      content.slideUp( 'fast' );
 789                      help.attr( 'aria-expanded', 'false' );
 790                  }
 791  
 792                  if ( 'true' === button.attr( 'aria-expanded' ) ) {
 793                      button.attr( 'aria-expanded', 'false' );
 794                      panelMeta.removeClass( 'open' );
 795                      panelMeta.removeClass( 'active-menu-screen-options' );
 796                      options.slideUp( 'fast' );
 797                  } else {
 798                      button.attr( 'aria-expanded', 'true' );
 799                      panelMeta.addClass( 'open' );
 800                      panelMeta.addClass( 'active-menu-screen-options' );
 801                      options.slideDown( 'fast' );
 802                  }
 803  
 804                  return false;
 805              } );
 806  
 807              // Help toggle.
 808              help.on( 'click keydown', function( event ) {
 809                  if ( api.utils.isKeydownButNotEnterEvent( event ) ) {
 810                      return;
 811                  }
 812                  event.preventDefault();
 813  
 814                  if ( 'true' === button.attr( 'aria-expanded' ) ) {
 815                      button.attr( 'aria-expanded', 'false' );
 816                      help.attr( 'aria-expanded', 'true' );
 817                      panelMeta.addClass( 'open' );
 818                      panelMeta.removeClass( 'active-menu-screen-options' );
 819                      options.slideUp( 'fast' );
 820                      content.slideDown( 'fast' );
 821                  }
 822              } );
 823          },
 824  
 825          /**
 826           * Update field visibility when clicking on the field toggles.
 827           */
 828          ready: function() {
 829              var panel = this;
 830              panel.container.find( '.hide-column-tog' ).on( 'click', function() {
 831                  panel.saveManageColumnsState();
 832              });
 833  
 834              // Inject additional heading into the menu locations section's head container.
 835              api.section( 'menu_locations', function( section ) {
 836                  section.headContainer.prepend(
 837                      wp.template( 'nav-menu-locations-header' )( api.Menus.data )
 838                  );
 839              } );
 840          },
 841  
 842          /**
 843           * Save hidden column states.
 844           *
 845           * @since 4.3.0
 846           * @private
 847           *
 848           * @return {void}
 849           */
 850          saveManageColumnsState: _.debounce( function() {
 851              var panel = this;
 852              if ( panel._updateHiddenColumnsRequest ) {
 853                  panel._updateHiddenColumnsRequest.abort();
 854              }
 855  
 856              panel._updateHiddenColumnsRequest = wp.ajax.post( 'hidden-columns', {
 857                  hidden: panel.hidden(),
 858                  screenoptionnonce: $( '#screenoptionnonce' ).val(),
 859                  page: 'nav-menus'
 860              } );
 861              panel._updateHiddenColumnsRequest.always( function() {
 862                  panel._updateHiddenColumnsRequest = null;
 863              } );
 864          }, 2000 ),
 865  
 866          /**
 867           * @deprecated Since 4.7.0 now that the nav_menu sections are responsible for toggling the classes on their own containers.
 868           */
 869          checked: function() {},
 870  
 871          /**
 872           * @deprecated Since 4.7.0 now that the nav_menu sections are responsible for toggling the classes on their own containers.
 873           */
 874          unchecked: function() {},
 875  
 876          /**
 877           * Get hidden fields.
 878           *
 879           * @since 4.3.0
 880           * @private
 881           *
 882           * @return {Array} Fields (columns) that are hidden.
 883           */
 884          hidden: function() {
 885              return $( '.hide-column-tog' ).not( ':checked' ).map( function() {
 886                  var id = this.id;
 887                  return id.substring( 0, id.length - 5 );
 888              }).get().join( ',' );
 889          }
 890      } );
 891  
 892      /**
 893       * wp.customize.Menus.MenuSection
 894       *
 895       * Customizer section for menus. This is used only for lazy-loading child controls.
 896       * Note that 'nav_menu' must match the WP_Customize_Menu_Section::$type.
 897       *
 898       * @class    wp.customize.Menus.MenuSection
 899       * @augments wp.customize.Section
 900       */
 901      api.Menus.MenuSection = api.Section.extend(/** @lends wp.customize.Menus.MenuSection.prototype */{
 902  
 903          /**
 904           * Initialize.
 905           *
 906           * @since 4.3.0
 907           *
 908           * @param {string} id
 909           * @param {Object} options
 910           */
 911          initialize: function( id, options ) {
 912              var section = this;
 913              api.Section.prototype.initialize.call( section, id, options );
 914              section.deferred.initSortables = $.Deferred();
 915          },
 916  
 917          /**
 918           * Ready.
 919           */
 920          ready: function() {
 921              var section = this, fieldActiveToggles, handleFieldActiveToggle;
 922  
 923              if ( 'undefined' === typeof section.params.menu_id ) {
 924                  throw new Error( 'params.menu_id was not defined' );
 925              }
 926  
 927              /*
 928               * Since newly created sections won't be registered in PHP, we need to prevent the
 929               * preview's sending of the activeSections to result in this control
 930               * being deactivated when the preview refreshes. So we can hook onto
 931               * the setting that has the same ID and its presence can dictate
 932               * whether the section is active.
 933               */
 934              section.active.validate = function() {
 935                  if ( ! api.has( section.id ) ) {
 936                      return false;
 937                  }
 938                  return !! api( section.id ).get();
 939              };
 940  
 941              section.populateControls();
 942  
 943              section.navMenuLocationSettings = {};
 944              section.assignedLocations = new api.Value( [] );
 945  
 946              api.each(function( setting, id ) {
 947                  var matches = id.match( /^nav_menu_locations\[(.+?)]/ );
 948                  if ( matches ) {
 949                      section.navMenuLocationSettings[ matches[1] ] = setting;
 950                      setting.bind( function() {
 951                          section.refreshAssignedLocations();
 952                      });
 953                  }
 954              });
 955  
 956              section.assignedLocations.bind(function( to ) {
 957                  section.updateAssignedLocationsInSectionTitle( to );
 958              });
 959  
 960              section.refreshAssignedLocations();
 961  
 962              api.bind( 'pane-contents-reflowed', function() {
 963                  // Skip menus that have been removed.
 964                  if ( ! section.contentContainer.parent().length ) {
 965                      return;
 966                  }
 967                  section.container.find( '.menu-item .menu-item-reorder-nav button' ).attr({ 'tabindex': '0', 'aria-hidden': 'false' });
 968                  section.container.find( '.menu-item.move-up-disabled .menus-move-up' ).attr({ 'tabindex': '-1', 'aria-hidden': 'true' });
 969                  section.container.find( '.menu-item.move-down-disabled .menus-move-down' ).attr({ 'tabindex': '-1', 'aria-hidden': 'true' });
 970                  section.container.find( '.menu-item.move-left-disabled .menus-move-left' ).attr({ 'tabindex': '-1', 'aria-hidden': 'true' });
 971                  section.container.find( '.menu-item.move-right-disabled .menus-move-right' ).attr({ 'tabindex': '-1', 'aria-hidden': 'true' });
 972              } );
 973  
 974              /**
 975               * Update the active field class for the content container for a given checkbox toggle.
 976               *
 977               * @this {jQuery}
 978               * @return {void}
 979               */
 980              handleFieldActiveToggle = function() {
 981                  var className = 'field-' + $( this ).val() + '-active';
 982                  section.contentContainer.toggleClass( className, $( this ).prop( 'checked' ) );
 983              };
 984              fieldActiveToggles = api.panel( 'nav_menus' ).contentContainer.find( '.metabox-prefs:first' ).find( '.hide-column-tog' );
 985              fieldActiveToggles.each( handleFieldActiveToggle );
 986              fieldActiveToggles.on( 'click', handleFieldActiveToggle );
 987          },
 988  
 989          populateControls: function() {
 990              var section = this,
 991                  menuNameControlId,
 992                  menuLocationsControlId,
 993                  menuAutoAddControlId,
 994                  menuDeleteControlId,
 995                  menuControl,
 996                  menuNameControl,
 997                  menuLocationsControl,
 998                  menuAutoAddControl,
 999                  menuDeleteControl;
1000  
1001              // Add the control for managing the menu name.
1002              menuNameControlId = section.id + '[name]';
1003              menuNameControl = api.control( menuNameControlId );
1004              if ( ! menuNameControl ) {
1005                  menuNameControl = new api.controlConstructor.nav_menu_name( menuNameControlId, {
1006                      type: 'nav_menu_name',
1007                      label: api.Menus.data.l10n.menuNameLabel,
1008                      section: section.id,
1009                      priority: 0,
1010                      settings: {
1011                          'default': section.id
1012                      }
1013                  } );
1014                  api.control.add( menuNameControl );
1015                  menuNameControl.active.set( true );
1016              }
1017  
1018              // Add the menu control.
1019              menuControl = api.control( section.id );
1020              if ( ! menuControl ) {
1021                  menuControl = new api.controlConstructor.nav_menu( section.id, {
1022                      type: 'nav_menu',
1023                      section: section.id,
1024                      priority: 998,
1025                      settings: {
1026                          'default': section.id
1027                      },
1028                      menu_id: section.params.menu_id
1029                  } );
1030                  api.control.add( menuControl );
1031                  menuControl.active.set( true );
1032              }
1033  
1034              // Add the menu locations control.
1035              menuLocationsControlId = section.id + '[locations]';
1036              menuLocationsControl = api.control( menuLocationsControlId );
1037              if ( ! menuLocationsControl ) {
1038                  menuLocationsControl = new api.controlConstructor.nav_menu_locations( menuLocationsControlId, {
1039                      section: section.id,
1040                      priority: 999,
1041                      settings: {
1042                          'default': section.id
1043                      },
1044                      menu_id: section.params.menu_id
1045                  } );
1046                  api.control.add( menuLocationsControl.id, menuLocationsControl );
1047                  menuControl.active.set( true );
1048              }
1049  
1050              // Add the control for managing the menu auto_add.
1051              menuAutoAddControlId = section.id + '[auto_add]';
1052              menuAutoAddControl = api.control( menuAutoAddControlId );
1053              if ( ! menuAutoAddControl ) {
1054                  menuAutoAddControl = new api.controlConstructor.nav_menu_auto_add( menuAutoAddControlId, {
1055                      type: 'nav_menu_auto_add',
1056                      label: '',
1057                      section: section.id,
1058                      priority: 1000,
1059                      settings: {
1060                          'default': section.id
1061                      }
1062                  } );
1063                  api.control.add( menuAutoAddControl );
1064                  menuAutoAddControl.active.set( true );
1065              }
1066  
1067              // Add the control for deleting the menu.
1068              menuDeleteControlId = section.id + '[delete]';
1069              menuDeleteControl = api.control( menuDeleteControlId );
1070              if ( ! menuDeleteControl ) {
1071                  menuDeleteControl = new api.Control( menuDeleteControlId, {
1072                      section: section.id,
1073                      priority: 1001,
1074                      templateId: 'nav-menu-delete-button'
1075                  } );
1076                  api.control.add( menuDeleteControl.id, menuDeleteControl );
1077                  menuDeleteControl.active.set( true );
1078                  menuDeleteControl.deferred.embedded.done( function () {
1079                      menuDeleteControl.container.find( 'button' ).on( 'click', function() {
1080                          var menuId = section.params.menu_id;
1081                          var menuControl = api.Menus.getMenuControl( menuId );
1082                          menuControl.setting.set( false );
1083                      });
1084                  } );
1085              }
1086          },
1087  
1088          /**
1089           *
1090           */
1091          refreshAssignedLocations: function() {
1092              var section = this,
1093                  menuTermId = section.params.menu_id,
1094                  currentAssignedLocations = [];
1095              _.each( section.navMenuLocationSettings, function( setting, themeLocation ) {
1096                  if ( setting() === menuTermId ) {
1097                      currentAssignedLocations.push( themeLocation );
1098                  }
1099              });
1100              section.assignedLocations.set( currentAssignedLocations );
1101          },
1102  
1103          /**
1104           * @param {Array} themeLocationSlugs Theme location slugs.
1105           */
1106          updateAssignedLocationsInSectionTitle: function( themeLocationSlugs ) {
1107              var section = this,
1108                  $title;
1109  
1110              $title = section.container.find( '.accordion-section-title:first' );
1111              $title.find( '.menu-in-location' ).remove();
1112              _.each( themeLocationSlugs, function( themeLocationSlug ) {
1113                  var $label, locationName;
1114                  $label = $( '<span class="menu-in-location"></span>' );
1115                  locationName = api.Menus.data.locationSlugMappedToName[ themeLocationSlug ];
1116                  $label.text( api.Menus.data.l10n.menuLocation.replace( '%s', locationName ) );
1117                  $title.append( $label );
1118              });
1119  
1120              section.container.toggleClass( 'assigned-to-menu-location', 0 !== themeLocationSlugs.length );
1121  
1122          },
1123  
1124          onChangeExpanded: function( expanded, args ) {
1125              var section = this, completeCallback;
1126  
1127              if ( expanded ) {
1128                  wpNavMenu.menuList = section.contentContainer;
1129                  wpNavMenu.targetList = wpNavMenu.menuList;
1130  
1131                  // Add attributes needed by wpNavMenu.
1132                  $( '#menu-to-edit' ).removeAttr( 'id' );
1133                  wpNavMenu.menuList.attr( 'id', 'menu-to-edit' ).addClass( 'menu' );
1134  
1135                  _.each( api.section( section.id ).controls(), function( control ) {
1136                      if ( 'nav_menu_item' === control.params.type ) {
1137                          control.actuallyEmbed();
1138                      }
1139                  } );
1140  
1141                  // Make sure Sortables is initialized after the section has been expanded to prevent `offset` issues.
1142                  if ( args.completeCallback ) {
1143                      completeCallback = args.completeCallback;
1144                  }
1145                  args.completeCallback = function() {
1146                      if ( 'resolved' !== section.deferred.initSortables.state() ) {
1147                          wpNavMenu.initSortables(); // Depends on menu-to-edit ID being set above.
1148                          section.deferred.initSortables.resolve( wpNavMenu.menuList ); // Now MenuControl can extend the sortable.
1149  
1150                          // @todo Note that wp.customize.reflowPaneContents() is debounced,
1151                          // so this immediate change will show a slight flicker while priorities get updated.
1152                          api.control( 'nav_menu[' + String( section.params.menu_id ) + ']' ).reflowMenuItems();
1153                      }
1154                      if ( _.isFunction( completeCallback ) ) {
1155                          completeCallback();
1156                      }
1157                  };
1158              }
1159              api.Section.prototype.onChangeExpanded.call( section, expanded, args );
1160          },
1161  
1162          /**
1163           * Highlight how a user may create new menu items.
1164           *
1165           * This method reminds the user to create new menu items and how.
1166           * It's exposed this way because this class knows best which UI needs
1167           * highlighted but those expanding this section know more about why and
1168           * when the affordance should be highlighted.
1169           *
1170           * @since 4.9.0
1171           *
1172           * @return {void}
1173           */
1174          highlightNewItemButton: function() {
1175              api.utils.highlightButton( this.contentContainer.find( '.add-new-menu-item' ), { delay: 2000 } );
1176          }
1177      });
1178  
1179      /**
1180       * Create a nav menu setting and section.
1181       *
1182       * @since 4.9.0
1183       *
1184       * @param {string} [name=''] Nav menu name.
1185       * @return {wp.customize.Menus.MenuSection} Added nav menu.
1186       */
1187      api.Menus.createNavMenu = function createNavMenu( name ) {
1188          var customizeId, placeholderId, setting;
1189          placeholderId = api.Menus.generatePlaceholderAutoIncrementId();
1190  
1191          customizeId = 'nav_menu[' + String( placeholderId ) + ']';
1192  
1193          // Register the menu control setting.
1194          setting = api.create( customizeId, customizeId, {}, {
1195              type: 'nav_menu',
1196              transport: api.Menus.data.settingTransport,
1197              previewer: api.previewer
1198          } );
1199          setting.set( $.extend(
1200              {},
1201              api.Menus.data.defaultSettingValues.nav_menu,
1202              {
1203                  name: name || ''
1204              }
1205          ) );
1206  
1207          /*
1208           * Add the menu section (and its controls).
1209           * Note that this will automatically create the required controls
1210           * inside via the Section's ready method.
1211           */
1212          return api.section.add( new api.Menus.MenuSection( customizeId, {
1213              panel: 'nav_menus',
1214              title: displayNavMenuName( name ),
1215              customizeAction: api.Menus.data.l10n.customizingMenus,
1216              priority: 10,
1217              menu_id: placeholderId
1218          } ) );
1219      };
1220  
1221      /**
1222       * wp.customize.Menus.NewMenuSection
1223       *
1224       * Customizer section for new menus.
1225       *
1226       * @class    wp.customize.Menus.NewMenuSection
1227       * @augments wp.customize.Section
1228       */
1229      api.Menus.NewMenuSection = api.Section.extend(/** @lends wp.customize.Menus.NewMenuSection.prototype */{
1230  
1231          /**
1232           * Add behaviors for the accordion section.
1233           *
1234           * @since 4.3.0
1235           */
1236          attachEvents: function() {
1237              var section = this,
1238                  container = section.container,
1239                  contentContainer = section.contentContainer,
1240                  navMenuSettingPattern = /^nav_menu\[/;
1241  
1242              section.headContainer.find( '.accordion-section-title' ).replaceWith(
1243                  wp.template( 'nav-menu-create-menu-section-title' )
1244              );
1245  
1246              /*
1247               * We have to manually handle section expanded because we do not
1248               * apply the `accordion-section-title` class to this button-driven section.
1249               */
1250              container.on( 'click', '.customize-add-menu-button', function() {
1251                  section.expand();
1252              });
1253  
1254              contentContainer.on( 'keydown', '.menu-name-field', function( event ) {
1255                  if ( 13 === event.which ) { // Enter.
1256                      section.submit();
1257                  }
1258              } );
1259              contentContainer.on( 'click', '#customize-new-menu-submit', function( event ) {
1260                  section.submit();
1261                  event.stopPropagation();
1262                  event.preventDefault();
1263              } );
1264  
1265              /**
1266               * Get number of non-deleted nav menus.
1267               *
1268               * @since 4.9.0
1269               * @return {number} Count.
1270               */
1271  			function getNavMenuCount() {
1272                  var count = 0;
1273                  api.each( function( setting ) {
1274                      if ( navMenuSettingPattern.test( setting.id ) && false !== setting.get() ) {
1275                          count += 1;
1276                      }
1277                  } );
1278                  return count;
1279              }
1280  
1281              /**
1282               * Update visibility of notice to prompt users to create menus.
1283               *
1284               * @since 4.9.0
1285               * @return {void}
1286               */
1287  			function updateNoticeVisibility() {
1288                  container.find( '.add-new-menu-notice' ).prop( 'hidden', getNavMenuCount() > 0 );
1289              }
1290  
1291              /**
1292               * Handle setting addition.
1293               *
1294               * @since 4.9.0
1295               * @param {wp.customize.Setting} setting - Added setting.
1296               * @return {void}
1297               */
1298  			function addChangeEventListener( setting ) {
1299                  if ( navMenuSettingPattern.test( setting.id ) ) {
1300                      setting.bind( updateNoticeVisibility );
1301                      updateNoticeVisibility();
1302                  }
1303              }
1304  
1305              /**
1306               * Handle setting removal.
1307               *
1308               * @since 4.9.0
1309               * @param {wp.customize.Setting} setting - Removed setting.
1310               * @return {void}
1311               */
1312  			function removeChangeEventListener( setting ) {
1313                  if ( navMenuSettingPattern.test( setting.id ) ) {
1314                      setting.unbind( updateNoticeVisibility );
1315                      updateNoticeVisibility();
1316                  }
1317              }
1318  
1319              api.each( addChangeEventListener );
1320              api.bind( 'add', addChangeEventListener );
1321              api.bind( 'removed', removeChangeEventListener );
1322              updateNoticeVisibility();
1323  
1324              api.Section.prototype.attachEvents.apply( section, arguments );
1325          },
1326  
1327          /**
1328           * Set up the control.
1329           *
1330           * @since 4.9.0
1331           */
1332          ready: function() {
1333              this.populateControls();
1334          },
1335  
1336          /**
1337           * Create the controls for this section.
1338           *
1339           * @since 4.9.0
1340           */
1341          populateControls: function() {
1342              var section = this,
1343                  menuNameControlId,
1344                  menuLocationsControlId,
1345                  newMenuSubmitControlId,
1346                  menuNameControl,
1347                  menuLocationsControl,
1348                  newMenuSubmitControl;
1349  
1350              menuNameControlId = section.id + '[name]';
1351              menuNameControl = api.control( menuNameControlId );
1352              if ( ! menuNameControl ) {
1353                  menuNameControl = new api.controlConstructor.nav_menu_name( menuNameControlId, {
1354                      label: api.Menus.data.l10n.menuNameLabel,
1355                      description: api.Menus.data.l10n.newMenuNameDescription,
1356                      section: section.id,
1357                      priority: 0
1358                  } );
1359                  api.control.add( menuNameControl.id, menuNameControl );
1360                  menuNameControl.active.set( true );
1361              }
1362  
1363              menuLocationsControlId = section.id + '[locations]';
1364              menuLocationsControl = api.control( menuLocationsControlId );
1365              if ( ! menuLocationsControl ) {
1366                  menuLocationsControl = new api.controlConstructor.nav_menu_locations( menuLocationsControlId, {
1367                      section: section.id,
1368                      priority: 1,
1369                      menu_id: '',
1370                      isCreating: true
1371                  } );
1372                  api.control.add( menuLocationsControlId, menuLocationsControl );
1373                  menuLocationsControl.active.set( true );
1374              }
1375  
1376              newMenuSubmitControlId = section.id + '[submit]';
1377              newMenuSubmitControl = api.control( newMenuSubmitControlId );
1378              if ( !newMenuSubmitControl ) {
1379                  newMenuSubmitControl = new api.Control( newMenuSubmitControlId, {
1380                      section: section.id,
1381                      priority: 1,
1382                      templateId: 'nav-menu-submit-new-button'
1383                  } );
1384                  api.control.add( newMenuSubmitControlId, newMenuSubmitControl );
1385                  newMenuSubmitControl.active.set( true );
1386              }
1387          },
1388  
1389          /**
1390           * Create the new menu with name and location supplied by the user.
1391           *
1392           * @since 4.9.0
1393           */
1394          submit: function() {
1395              var section = this,
1396                  contentContainer = section.contentContainer,
1397                  nameInput = contentContainer.find( '.menu-name-field' ).first(),
1398                  name = nameInput.val(),
1399                  menuSection;
1400  
1401              if ( ! name ) {
1402                  nameInput.addClass( 'invalid' );
1403                  nameInput.focus();
1404                  return;
1405              }
1406  
1407              menuSection = api.Menus.createNavMenu( name );
1408  
1409              // Clear name field.
1410              nameInput.val( '' );
1411              nameInput.removeClass( 'invalid' );
1412  
1413              contentContainer.find( '.assigned-menu-location input[type=checkbox]' ).each( function() {
1414                  var checkbox = $( this ),
1415                  navMenuLocationSetting;
1416  
1417                  if ( checkbox.prop( 'checked' ) ) {
1418                      navMenuLocationSetting = api( 'nav_menu_locations[' + checkbox.data( 'location-id' ) + ']' );
1419                      navMenuLocationSetting.set( menuSection.params.menu_id );
1420  
1421                      // Reset state for next new menu.
1422                      checkbox.prop( 'checked', false );
1423                  }
1424              } );
1425  
1426              wp.a11y.speak( api.Menus.data.l10n.menuAdded );
1427  
1428              // Focus on the new menu section.
1429              menuSection.focus( {
1430                  completeCallback: function() {
1431                      menuSection.highlightNewItemButton();
1432                  }
1433              } );
1434          },
1435  
1436          /**
1437           * Select a default location.
1438           *
1439           * This method selects a single location by default so we can support
1440           * creating a menu for a specific menu location.
1441           *
1442           * @since 4.9.0
1443           *
1444           * @param {string|null} locationId - The ID of the location to select. `null` clears all selections.
1445           * @return {void}
1446           */
1447          selectDefaultLocation: function( locationId ) {
1448              var locationControl = api.control( this.id + '[locations]' ),
1449                  locationSelections = {};
1450  
1451              if ( locationId !== null ) {
1452                  locationSelections[ locationId ] = true;
1453              }
1454  
1455              locationControl.setSelections( locationSelections );
1456          }
1457      });
1458  
1459      /**
1460       * wp.customize.Menus.MenuLocationControl
1461       *
1462       * Customizer control for menu locations (rendered as a <select>).
1463       * Note that 'nav_menu_location' must match the WP_Customize_Nav_Menu_Location_Control::$type.
1464       *
1465       * @class    wp.customize.Menus.MenuLocationControl
1466       * @augments wp.customize.Control
1467       */
1468      api.Menus.MenuLocationControl = api.Control.extend(/** @lends wp.customize.Menus.MenuLocationControl.prototype */{
1469          initialize: function( id, options ) {
1470              var control = this,
1471                  matches = id.match( /^nav_menu_locations\[(.+?)]/ );
1472              control.themeLocation = matches[1];
1473              api.Control.prototype.initialize.call( control, id, options );
1474          },
1475  
1476          ready: function() {
1477              var control = this, navMenuIdRegex = /^nav_menu\[(-?\d+)]/;
1478  
1479              // @todo It would be better if this was added directly on the setting itself, as opposed to the control.
1480              control.setting.validate = function( value ) {
1481                  if ( '' === value ) {
1482                      return 0;
1483                  } else {
1484                      return parseInt( value, 10 );
1485                  }
1486              };
1487  
1488              // Create and Edit menu buttons.
1489              control.container.find( '.create-menu' ).on( 'click', function() {
1490                  var addMenuSection = api.section( 'add_menu' );
1491                  addMenuSection.selectDefaultLocation( this.dataset.locationId );
1492                  addMenuSection.focus();
1493              } );
1494              control.container.find( '.edit-menu' ).on( 'click', function() {
1495                  var menuId = control.setting();
1496                  api.section( 'nav_menu[' + menuId + ']' ).focus();
1497              });
1498              control.setting.bind( 'change', function() {
1499                  var menuIsSelected = 0 !== control.setting();
1500                  control.container.find( '.create-menu' ).toggleClass( 'hidden', menuIsSelected );
1501                  control.container.find( '.edit-menu' ).toggleClass( 'hidden', ! menuIsSelected );
1502              });
1503  
1504              // Add/remove menus from the available options when they are added and removed.
1505              api.bind( 'add', function( setting ) {
1506                  var option, menuId, matches = setting.id.match( navMenuIdRegex );
1507                  if ( ! matches || false === setting() ) {
1508                      return;
1509                  }
1510                  menuId = matches[1];
1511                  option = new Option( displayNavMenuName( setting().name ), menuId );
1512                  control.container.find( 'select' ).append( option );
1513              });
1514              api.bind( 'remove', function( setting ) {
1515                  var menuId, matches = setting.id.match( navMenuIdRegex );
1516                  if ( ! matches ) {
1517                      return;
1518                  }
1519                  menuId = parseInt( matches[1], 10 );
1520                  if ( control.setting() === menuId ) {
1521                      control.setting.set( '' );
1522                  }
1523                  control.container.find( 'option[value=' + menuId + ']' ).remove();
1524              });
1525              api.bind( 'change', function( setting ) {
1526                  var menuId, matches = setting.id.match( navMenuIdRegex );
1527                  if ( ! matches ) {
1528                      return;
1529                  }
1530                  menuId = parseInt( matches[1], 10 );
1531                  if ( false === setting() ) {
1532                      if ( control.setting() === menuId ) {
1533                          control.setting.set( '' );
1534                      }
1535                      control.container.find( 'option[value=' + menuId + ']' ).remove();
1536                  } else {
1537                      control.container.find( 'option[value=' + menuId + ']' ).text( displayNavMenuName( setting().name ) );
1538                  }
1539              });
1540          }
1541      });
1542  
1543      api.Menus.MenuItemControl = api.Control.extend(/** @lends wp.customize.Menus.MenuItemControl.prototype */{
1544  
1545          /**
1546           * wp.customize.Menus.MenuItemControl
1547           *
1548           * Customizer control for menu items.
1549           * Note that 'menu_item' must match the WP_Customize_Menu_Item_Control::$type.
1550           *
1551           * @constructs wp.customize.Menus.MenuItemControl
1552           * @augments   wp.customize.Control
1553           *
1554           * @inheritDoc
1555           */
1556          initialize: function( id, options ) {
1557              var control = this;
1558              control.expanded = new api.Value( false );
1559              control.expandedArgumentsQueue = [];
1560              control.expanded.bind( function( expanded ) {
1561                  var args = control.expandedArgumentsQueue.shift();
1562                  args = $.extend( {}, control.defaultExpandedArguments, args );
1563                  control.onChangeExpanded( expanded, args );
1564              });
1565              api.Control.prototype.initialize.call( control, id, options );
1566              control.active.validate = function() {
1567                  var value, section = api.section( control.section() );
1568                  if ( section ) {
1569                      value = section.active();
1570                  } else {
1571                      value = false;
1572                  }
1573                  return value;
1574              };
1575          },
1576  
1577          /**
1578           * Override the embed() method to do nothing,
1579           * so that the control isn't embedded on load,
1580           * unless the containing section is already expanded.
1581           *
1582           * @since 4.3.0
1583           */
1584          embed: function() {
1585              var control = this,
1586                  sectionId = control.section(),
1587                  section;
1588              if ( ! sectionId ) {
1589                  return;
1590              }
1591              section = api.section( sectionId );
1592              if ( ( section && section.expanded() ) || api.settings.autofocus.control === control.id ) {
1593                  control.actuallyEmbed();
1594              }
1595          },
1596  
1597          /**
1598           * This function is called in Section.onChangeExpanded() so the control
1599           * will only get embedded when the Section is first expanded.
1600           *
1601           * @since 4.3.0
1602           */
1603          actuallyEmbed: function() {
1604              var control = this;
1605              if ( 'resolved' === control.deferred.embedded.state() ) {
1606                  return;
1607              }
1608              control.renderContent();
1609              control.deferred.embedded.resolve(); // This triggers control.ready().
1610          },
1611  
1612          /**
1613           * Set up the control.
1614           */
1615          ready: function() {
1616              if ( 'undefined' === typeof this.params.menu_item_id ) {
1617                  throw new Error( 'params.menu_item_id was not defined' );
1618              }
1619  
1620              this._setupControlToggle();
1621              this._setupReorderUI();
1622              this._setupUpdateUI();
1623              this._setupRemoveUI();
1624              this._setupLinksUI();
1625              this._setupTitleUI();
1626          },
1627  
1628          /**
1629           * Show/hide the settings when clicking on the menu item handle.
1630           */
1631          _setupControlToggle: function() {
1632              var control = this;
1633  
1634              this.container.find( '.menu-item-handle' ).on( 'click', function( e ) {
1635                  e.preventDefault();
1636                  e.stopPropagation();
1637                  var menuControl = control.getMenuControl(),
1638                      isDeleteBtn = $( e.target ).is( '.item-delete, .item-delete *' ),
1639                      isAddNewBtn = $( e.target ).is( '.add-new-menu-item, .add-new-menu-item *' );
1640  
1641                  if ( $( 'body' ).hasClass( 'adding-menu-items' ) && ! isDeleteBtn && ! isAddNewBtn ) {
1642                      api.Menus.availableMenuItemsPanel.close();
1643                  }
1644  
1645                  if ( menuControl.isReordering || menuControl.isSorting ) {
1646                      return;
1647                  }
1648                  control.toggleForm();
1649              } );
1650          },
1651  
1652          /**
1653           * Set up the menu-item-reorder-nav
1654           */
1655          _setupReorderUI: function() {
1656              var control = this, template, $reorderNav;
1657  
1658              template = wp.template( 'menu-item-reorder-nav' );
1659  
1660              // Add the menu item reordering elements to the menu item control.
1661              control.container.find( '.item-controls' ).after( template );
1662  
1663              // Handle clicks for up/down/left-right on the reorder nav.
1664              $reorderNav = control.container.find( '.menu-item-reorder-nav' );
1665              $reorderNav.find( '.menus-move-up, .menus-move-down, .menus-move-left, .menus-move-right' ).on( 'click', function() {
1666                  var moveBtn = $( this );
1667                  moveBtn.focus();
1668  
1669                  var isMoveUp = moveBtn.is( '.menus-move-up' ),
1670                      isMoveDown = moveBtn.is( '.menus-move-down' ),
1671                      isMoveLeft = moveBtn.is( '.menus-move-left' ),
1672                      isMoveRight = moveBtn.is( '.menus-move-right' );
1673  
1674                  if ( isMoveUp ) {
1675                      control.moveUp();
1676                  } else if ( isMoveDown ) {
1677                      control.moveDown();
1678                  } else if ( isMoveLeft ) {
1679                      control.moveLeft();
1680                  } else if ( isMoveRight ) {
1681                      control.moveRight();
1682                  }
1683  
1684                  moveBtn.focus(); // Re-focus after the container was moved.
1685              } );
1686          },
1687  
1688          /**
1689           * Set up event handlers for menu item updating.
1690           */
1691          _setupUpdateUI: function() {
1692              var control = this,
1693                  settingValue = control.setting(),
1694                  updateNotifications;
1695  
1696              control.elements = {};
1697              control.elements.url = new api.Element( control.container.find( '.edit-menu-item-url' ) );
1698              control.elements.title = new api.Element( control.container.find( '.edit-menu-item-title' ) );
1699              control.elements.attr_title = new api.Element( control.container.find( '.edit-menu-item-attr-title' ) );
1700              control.elements.target = new api.Element( control.container.find( '.edit-menu-item-target' ) );
1701              control.elements.classes = new api.Element( control.container.find( '.edit-menu-item-classes' ) );
1702              control.elements.xfn = new api.Element( control.container.find( '.edit-menu-item-xfn' ) );
1703              control.elements.description = new api.Element( control.container.find( '.edit-menu-item-description' ) );
1704              // @todo Allow other elements, added by plugins, to be automatically picked up here;
1705              // allow additional values to be added to setting array.
1706  
1707              _.each( control.elements, function( element, property ) {
1708                  element.bind(function( value ) {
1709                      if ( element.element.is( 'input[type=checkbox]' ) ) {
1710                          value = ( value ) ? element.element.val() : '';
1711                      }
1712  
1713                      var settingValue = control.setting();
1714                      if ( settingValue && settingValue[ property ] !== value ) {
1715                          settingValue = _.clone( settingValue );
1716                          settingValue[ property ] = value;
1717                          control.setting.set( settingValue );
1718                      }
1719                  });
1720                  if ( settingValue ) {
1721                      if ( ( property === 'classes' || property === 'xfn' ) && _.isArray( settingValue[ property ] ) ) {
1722                          element.set( settingValue[ property ].join( ' ' ) );
1723                      } else {
1724                          element.set( settingValue[ property ] );
1725                      }
1726                  }
1727              });
1728  
1729              control.setting.bind(function( to, from ) {
1730                  var itemId = control.params.menu_item_id,
1731                      followingSiblingItemControls = [],
1732                      childrenItemControls = [],
1733                      menuControl;
1734  
1735                  if ( false === to ) {
1736                      menuControl = api.control( 'nav_menu[' + String( from.nav_menu_term_id ) + ']' );
1737                      control.container.remove();
1738  
1739                      _.each( menuControl.getMenuItemControls(), function( otherControl ) {
1740                          if ( from.menu_item_parent === otherControl.setting().menu_item_parent && otherControl.setting().position > from.position ) {
1741                              followingSiblingItemControls.push( otherControl );
1742                          } else if ( otherControl.setting().menu_item_parent === itemId ) {
1743                              childrenItemControls.push( otherControl );
1744                          }
1745                      });
1746  
1747                      // Shift all following siblings by the number of children this item has.
1748                      _.each( followingSiblingItemControls, function( followingSiblingItemControl ) {
1749                          var value = _.clone( followingSiblingItemControl.setting() );
1750                          value.position += childrenItemControls.length;
1751                          followingSiblingItemControl.setting.set( value );
1752                      });
1753  
1754                      // Now move the children up to be the new subsequent siblings.
1755                      _.each( childrenItemControls, function( childrenItemControl, i ) {
1756                          var value = _.clone( childrenItemControl.setting() );
1757                          value.position = from.position + i;
1758                          value.menu_item_parent = from.menu_item_parent;
1759                          childrenItemControl.setting.set( value );
1760                      });
1761  
1762                      menuControl.debouncedReflowMenuItems();
1763                  } else {
1764                      // Update the elements' values to match the new setting properties.
1765                      _.each( to, function( value, key ) {
1766                          if ( control.elements[ key] ) {
1767                              control.elements[ key ].set( to[ key ] );
1768                          }
1769                      } );
1770                      control.container.find( '.menu-item-data-parent-id' ).val( to.menu_item_parent );
1771  
1772                      // Handle UI updates when the position or depth (parent) change.
1773                      if ( to.position !== from.position || to.menu_item_parent !== from.menu_item_parent ) {
1774                          control.getMenuControl().debouncedReflowMenuItems();
1775                      }
1776                  }
1777              });
1778  
1779              // Style the URL field as invalid when there is an invalid_url notification.
1780              updateNotifications = function() {
1781                  control.elements.url.element.toggleClass( 'invalid', control.setting.notifications.has( 'invalid_url' ) );
1782              };
1783              control.setting.notifications.bind( 'add', updateNotifications );
1784              control.setting.notifications.bind( 'removed', updateNotifications );
1785          },
1786  
1787          /**
1788           * Set up event handlers for menu item deletion.
1789           */
1790          _setupRemoveUI: function() {
1791              var control = this, $removeBtn;
1792  
1793              // Configure delete button.
1794              $removeBtn = control.container.find( '.item-delete' );
1795  
1796              $removeBtn.on( 'click', function() {
1797                  // Find an adjacent element to add focus to when this menu item goes away.
1798                  var addingItems = true, $adjacentFocusTarget, $next, $prev,
1799                      instanceCounter = 0, // Instance count of the menu item deleted.
1800                      deleteItemOriginalItemId = control.params.original_item_id,
1801                      addedItems = control.getMenuControl().$sectionContent.find( '.menu-item' ),
1802                      availableMenuItem;
1803  
1804                  if ( ! $( 'body' ).hasClass( 'adding-menu-items' ) ) {
1805                      addingItems = false;
1806                  }
1807  
1808                  $next = control.container.nextAll( '.customize-control-nav_menu_item:visible' ).first();
1809                  $prev = control.container.prevAll( '.customize-control-nav_menu_item:visible' ).first();
1810  
1811                  if ( $next.length ) {
1812                      $adjacentFocusTarget = $next.find( false === addingItems ? '.item-edit' : '.item-delete' ).first();
1813                  } else if ( $prev.length ) {
1814                      $adjacentFocusTarget = $prev.find( false === addingItems ? '.item-edit' : '.item-delete' ).first();
1815                  } else {
1816                      $adjacentFocusTarget = control.container.nextAll( '.customize-control-nav_menu' ).find( '.add-new-menu-item' ).first();
1817                  }
1818  
1819                  /*
1820                   * If the menu item deleted is the only of its instance left,
1821                   * remove the check icon of this menu item in the right panel.
1822                   */
1823                  _.each( addedItems, function( addedItem ) {
1824                      var menuItemId, menuItemControl, matches;
1825  
1826                      // This is because menu item that's deleted is just hidden.
1827                      if ( ! $( addedItem ).is( ':visible' ) ) {
1828                          return;
1829                      }
1830  
1831                      matches = addedItem.getAttribute( 'id' ).match( /^customize-control-nav_menu_item-(-?\d+)$/, '' );
1832                      if ( ! matches ) {
1833                          return;
1834                      }
1835  
1836                      menuItemId      = parseInt( matches[1], 10 );
1837                      menuItemControl = api.control( 'nav_menu_item[' + String( menuItemId ) + ']' );
1838  
1839                      // Check for duplicate menu items.
1840                      if ( menuItemControl && deleteItemOriginalItemId == menuItemControl.params.original_item_id ) {
1841                          instanceCounter++;
1842                      }
1843                  } );
1844  
1845                  if ( instanceCounter <= 1 ) {
1846                      // Revert the check icon to add icon.
1847                      availableMenuItem = $( '#menu-item-tpl-' + control.params.original_item_id );
1848                      availableMenuItem.removeClass( 'selected' );
1849                      availableMenuItem.find( '.menu-item-handle' ).removeClass( 'item-added' );
1850                  }
1851  
1852                  control.container.slideUp( function() {
1853                      control.setting.set( false );
1854                      wp.a11y.speak( api.Menus.data.l10n.itemDeleted );
1855                      $adjacentFocusTarget.focus(); // Keyboard accessibility.
1856                  } );
1857  
1858                  control.setting.set( false );
1859              } );
1860          },
1861  
1862          _setupLinksUI: function() {
1863              var $origBtn;
1864  
1865              // Configure original link.
1866              $origBtn = this.container.find( 'a.original-link' );
1867  
1868              $origBtn.on( 'click', function( e ) {
1869                  e.preventDefault();
1870                  api.previewer.previewUrl( e.target.toString() );
1871              } );
1872          },
1873  
1874          /**
1875           * Update item handle title when changed.
1876           */
1877          _setupTitleUI: function() {
1878              var control = this, titleEl;
1879  
1880              // Ensure that whitespace is trimmed on blur so placeholder can be shown.
1881              control.container.find( '.edit-menu-item-title' ).on( 'blur', function() {
1882                  $( this ).val( $( this ).val().trim() );
1883              } );
1884  
1885              titleEl = control.container.find( '.menu-item-title' );
1886              control.setting.bind( function( item ) {
1887                  var trimmedTitle, titleText;
1888                  if ( ! item ) {
1889                      return;
1890                  }
1891                  item.title = item.title || '';
1892                  trimmedTitle = item.title.trim();
1893  
1894                  titleText = trimmedTitle || item.original_title || api.Menus.data.l10n.untitled;
1895  
1896                  if ( item._invalid ) {
1897                      titleText = api.Menus.data.l10n.invalidTitleTpl.replace( '%s', titleText );
1898                  }
1899  
1900                  // Don't update to an empty title.
1901                  if ( trimmedTitle || item.original_title ) {
1902                      titleEl
1903                          .text( titleText )
1904                          .removeClass( 'no-title' );
1905                  } else {
1906                      titleEl
1907                          .text( titleText )
1908                          .addClass( 'no-title' );
1909                  }
1910              } );
1911          },
1912  
1913          /**
1914           *
1915           * @return {number}
1916           */
1917          getDepth: function() {
1918              var control = this, setting = control.setting(), depth = 0;
1919              if ( ! setting ) {
1920                  return 0;
1921              }
1922              while ( setting && setting.menu_item_parent ) {
1923                  depth += 1;
1924                  control = api.control( 'nav_menu_item[' + setting.menu_item_parent + ']' );
1925                  if ( ! control ) {
1926                      break;
1927                  }
1928                  setting = control.setting();
1929              }
1930              return depth;
1931          },
1932  
1933          /**
1934           * Amend the control's params with the data necessary for the JS template just in time.
1935           */
1936          renderContent: function() {
1937              var control = this,
1938                  settingValue = control.setting(),
1939                  containerClasses;
1940  
1941              control.params.title = settingValue.title || '';
1942              control.params.depth = control.getDepth();
1943              control.container.data( 'item-depth', control.params.depth );
1944              containerClasses = [
1945                  'menu-item',
1946                  'menu-item-depth-' + String( control.params.depth ),
1947                  'menu-item-' + settingValue.object,
1948                  'menu-item-edit-inactive'
1949              ];
1950  
1951              if ( settingValue._invalid ) {
1952                  containerClasses.push( 'menu-item-invalid' );
1953                  control.params.title = api.Menus.data.l10n.invalidTitleTpl.replace( '%s', control.params.title );
1954              } else if ( 'draft' === settingValue.status ) {
1955                  containerClasses.push( 'pending' );
1956                  control.params.title = api.Menus.data.pendingTitleTpl.replace( '%s', control.params.title );
1957              }
1958  
1959              control.params.el_classes = containerClasses.join( ' ' );
1960              control.params.item_type_label = settingValue.type_label;
1961              control.params.item_type = settingValue.type;
1962              control.params.url = settingValue.url;
1963              control.params.target = settingValue.target;
1964              control.params.attr_title = settingValue.attr_title;
1965              control.params.classes = _.isArray( settingValue.classes ) ? settingValue.classes.join( ' ' ) : settingValue.classes;
1966              control.params.xfn = settingValue.xfn;
1967              control.params.description = settingValue.description;
1968              control.params.parent = settingValue.menu_item_parent;
1969              control.params.original_title = settingValue.original_title || '';
1970  
1971              control.container.addClass( control.params.el_classes );
1972  
1973              api.Control.prototype.renderContent.call( control );
1974          },
1975  
1976          /***********************************************************************
1977           * Begin public API methods
1978           **********************************************************************/
1979  
1980          /**
1981           * @return {wp.customize.controlConstructor.nav_menu|null}
1982           */
1983          getMenuControl: function() {
1984              var control = this, settingValue = control.setting();
1985              if ( settingValue && settingValue.nav_menu_term_id ) {
1986                  return api.control( 'nav_menu[' + settingValue.nav_menu_term_id + ']' );
1987              } else {
1988                  return null;
1989              }
1990          },
1991  
1992          /**
1993           * Expand the accordion section containing a control
1994           */
1995          expandControlSection: function() {
1996              var $section = this.container.closest( '.accordion-section' );
1997              if ( ! $section.hasClass( 'open' ) ) {
1998                  $section.find( '.accordion-section-title:first' ).trigger( 'click' );
1999              }
2000          },
2001  
2002          /**
2003           * @since 4.6.0
2004           *
2005           * @param {Boolean} expanded
2006           * @param {Object} [params]
2007           * @return {Boolean} False if state already applied.
2008           */
2009          _toggleExpanded: api.Section.prototype._toggleExpanded,
2010  
2011          /**
2012           * @since 4.6.0
2013           *
2014           * @param {Object} [params]
2015           * @return {Boolean} False if already expanded.
2016           */
2017          expand: api.Section.prototype.expand,
2018  
2019          /**
2020           * Expand the menu item form control.
2021           *
2022           * @since 4.5.0 Added params.completeCallback.
2023           *
2024           * @param {Object}   [params] - Optional params.
2025           * @param {Function} [params.completeCallback] - Function to call when the form toggle has finished animating.
2026           */
2027          expandForm: function( params ) {
2028              this.expand( params );
2029          },
2030  
2031          /**
2032           * @since 4.6.0
2033           *
2034           * @param {Object} [params]
2035           * @return {Boolean} False if already collapsed.
2036           */
2037          collapse: api.Section.prototype.collapse,
2038  
2039          /**
2040           * Collapse the menu item form control.
2041           *
2042           * @since 4.5.0 Added params.completeCallback.
2043           *
2044           * @param {Object}   [params] - Optional params.
2045           * @param {Function} [params.completeCallback] - Function to call when the form toggle has finished animating.
2046           */
2047          collapseForm: function( params ) {
2048              this.collapse( params );
2049          },
2050  
2051          /**
2052           * Expand or collapse the menu item control.
2053           *
2054           * @deprecated this is poor naming, and it is better to directly set control.expanded( showOrHide )
2055           * @since 4.5.0 Added params.completeCallback.
2056           *
2057           * @param {boolean}  [showOrHide] - If not supplied, will be inverse of current visibility
2058           * @param {Object}   [params] - Optional params.
2059           * @param {Function} [params.completeCallback] - Function to call when the form toggle has finished animating.
2060           */
2061          toggleForm: function( showOrHide, params ) {
2062              if ( typeof showOrHide === 'undefined' ) {
2063                  showOrHide = ! this.expanded();
2064              }
2065              if ( showOrHide ) {
2066                  this.expand( params );
2067              } else {
2068                  this.collapse( params );
2069              }
2070          },
2071  
2072          /**
2073           * Expand or collapse the menu item control.
2074           *
2075           * @since 4.6.0
2076           * @param {boolean}  [showOrHide] - If not supplied, will be inverse of current visibility
2077           * @param {Object}   [params] - Optional params.
2078           * @param {Function} [params.completeCallback] - Function to call when the form toggle has finished animating.
2079           */
2080          onChangeExpanded: function( showOrHide, params ) {
2081              var self = this, $menuitem, $inside, complete;
2082  
2083              $menuitem = this.container;
2084              $inside = $menuitem.find( '.menu-item-settings:first' );
2085              if ( 'undefined' === typeof showOrHide ) {
2086                  showOrHide = ! $inside.is( ':visible' );
2087              }
2088  
2089              // Already expanded or collapsed.
2090              if ( $inside.is( ':visible' ) === showOrHide ) {
2091                  if ( params && params.completeCallback ) {
2092                      params.completeCallback();
2093                  }
2094                  return;
2095              }
2096  
2097              if ( showOrHide ) {
2098                  // Close all other menu item controls before expanding this one.
2099                  api.control.each( function( otherControl ) {
2100                      if ( self.params.type === otherControl.params.type && self !== otherControl ) {
2101                          otherControl.collapseForm();
2102                      }
2103                  } );
2104  
2105                  complete = function() {
2106                      $menuitem
2107                          .removeClass( 'menu-item-edit-inactive' )
2108                          .addClass( 'menu-item-edit-active' );
2109                      self.container.trigger( 'expanded' );
2110  
2111                      if ( params && params.completeCallback ) {
2112                          params.completeCallback();
2113                      }
2114                  };
2115  
2116                  $menuitem.find( '.item-edit' ).attr( 'aria-expanded', 'true' );
2117                  $inside.slideDown( 'fast', complete );
2118  
2119                  self.container.trigger( 'expand' );
2120              } else {
2121                  complete = function() {
2122                      $menuitem
2123                          .addClass( 'menu-item-edit-inactive' )
2124                          .removeClass( 'menu-item-edit-active' );
2125                      self.container.trigger( 'collapsed' );
2126  
2127                      if ( params && params.completeCallback ) {
2128                          params.completeCallback();
2129                      }
2130                  };
2131  
2132                  self.container.trigger( 'collapse' );
2133  
2134                  $menuitem.find( '.item-edit' ).attr( 'aria-expanded', 'false' );
2135                  $inside.slideUp( 'fast', complete );
2136              }
2137          },
2138  
2139          /**
2140           * Expand the containing menu section, expand the form, and focus on
2141           * the first input in the control.
2142           *
2143           * @since 4.5.0 Added params.completeCallback.
2144           *
2145           * @param {Object}   [params] - Params object.
2146           * @param {Function} [params.completeCallback] - Optional callback function when focus has completed.
2147           */
2148          focus: function( params ) {
2149              params = params || {};
2150              var control = this, originalCompleteCallback = params.completeCallback, focusControl;
2151  
2152              focusControl = function() {
2153                  control.expandControlSection();
2154  
2155                  params.completeCallback = function() {
2156                      var focusable;
2157  
2158                      // Note that we can't use :focusable due to a jQuery UI issue. See: https://github.com/jquery/jquery-ui/pull/1583
2159                      focusable = control.container.find( '.menu-item-settings' ).find( 'input, select, textarea, button, object, a[href], [tabindex]' ).filter( ':visible' );
2160                      focusable.first().focus();
2161  
2162                      if ( originalCompleteCallback ) {
2163                          originalCompleteCallback();
2164                      }
2165                  };
2166  
2167                  control.expandForm( params );
2168              };
2169  
2170              if ( api.section.has( control.section() ) ) {
2171                  api.section( control.section() ).expand( {
2172                      completeCallback: focusControl
2173                  } );
2174              } else {
2175                  focusControl();
2176              }
2177          },
2178  
2179          /**
2180           * Move menu item up one in the menu.
2181           */
2182          moveUp: function() {
2183              this._changePosition( -1 );
2184              wp.a11y.speak( api.Menus.data.l10n.movedUp );
2185          },
2186  
2187          /**
2188           * Move menu item up one in the menu.
2189           */
2190          moveDown: function() {
2191              this._changePosition( 1 );
2192              wp.a11y.speak( api.Menus.data.l10n.movedDown );
2193          },
2194          /**
2195           * Move menu item and all children up one level of depth.
2196           */
2197          moveLeft: function() {
2198              this._changeDepth( -1 );
2199              wp.a11y.speak( api.Menus.data.l10n.movedLeft );
2200          },
2201  
2202          /**
2203           * Move menu item and children one level deeper, as a submenu of the previous item.
2204           */
2205          moveRight: function() {
2206              this._changeDepth( 1 );
2207              wp.a11y.speak( api.Menus.data.l10n.movedRight );
2208          },
2209  
2210          /**
2211           * Note that this will trigger a UI update, causing child items to
2212           * move as well and cardinal order class names to be updated.
2213           *
2214           * @private
2215           *
2216           * @param {number} offset 1|-1
2217           */
2218          _changePosition: function( offset ) {
2219              var control = this,
2220                  adjacentSetting,
2221                  settingValue = _.clone( control.setting() ),
2222                  siblingSettings = [],
2223                  realPosition;
2224  
2225              if ( 1 !== offset && -1 !== offset ) {
2226                  throw new Error( 'Offset changes by 1 are only supported.' );
2227              }
2228  
2229              // Skip moving deleted items.
2230              if ( ! control.setting() ) {
2231                  return;
2232              }
2233  
2234              // Locate the other items under the same parent (siblings).
2235              _( control.getMenuControl().getMenuItemControls() ).each(function( otherControl ) {
2236                  if ( otherControl.setting().menu_item_parent === settingValue.menu_item_parent ) {
2237                      siblingSettings.push( otherControl.setting );
2238                  }
2239              });
2240              siblingSettings.sort(function( a, b ) {
2241                  return a().position - b().position;
2242              });
2243  
2244              realPosition = _.indexOf( siblingSettings, control.setting );
2245              if ( -1 === realPosition ) {
2246                  throw new Error( 'Expected setting to be among siblings.' );
2247              }
2248  
2249              // Skip doing anything if the item is already at the edge in the desired direction.
2250              if ( ( realPosition === 0 && offset < 0 ) || ( realPosition === siblingSettings.length - 1 && offset > 0 ) ) {
2251                  // @todo Should we allow a menu item to be moved up to break it out of a parent? Adopt with previous or following parent?
2252                  return;
2253              }
2254  
2255              // Update any adjacent menu item setting to take on this item's position.
2256              adjacentSetting = siblingSettings[ realPosition + offset ];
2257              if ( adjacentSetting ) {
2258                  adjacentSetting.set( $.extend(
2259                      _.clone( adjacentSetting() ),
2260                      {
2261                          position: settingValue.position
2262                      }
2263                  ) );
2264              }
2265  
2266              settingValue.position += offset;
2267              control.setting.set( settingValue );
2268          },
2269  
2270          /**
2271           * Note that this will trigger a UI update, causing child items to
2272           * move as well and cardinal order class names to be updated.
2273           *
2274           * @private
2275           *
2276           * @param {number} offset 1|-1
2277           */
2278          _changeDepth: function( offset ) {
2279              if ( 1 !== offset && -1 !== offset ) {
2280                  throw new Error( 'Offset changes by 1 are only supported.' );
2281              }
2282              var control = this,
2283                  settingValue = _.clone( control.setting() ),
2284                  siblingControls = [],
2285                  realPosition,
2286                  siblingControl,
2287                  parentControl;
2288  
2289              // Locate the other items under the same parent (siblings).
2290              _( control.getMenuControl().getMenuItemControls() ).each(function( otherControl ) {
2291                  if ( otherControl.setting().menu_item_parent === settingValue.menu_item_parent ) {
2292                      siblingControls.push( otherControl );
2293                  }
2294              });
2295              siblingControls.sort(function( a, b ) {
2296                  return a.setting().position - b.setting().position;
2297              });
2298  
2299              realPosition = _.indexOf( siblingControls, control );
2300              if ( -1 === realPosition ) {
2301                  throw new Error( 'Expected control to be among siblings.' );
2302              }
2303  
2304              if ( -1 === offset ) {
2305                  // Skip moving left an item that is already at the top level.
2306                  if ( ! settingValue.menu_item_parent ) {
2307                      return;
2308                  }
2309  
2310                  parentControl = api.control( 'nav_menu_item[' + settingValue.menu_item_parent + ']' );
2311  
2312                  // Make this control the parent of all the following siblings.
2313                  _( siblingControls ).chain().slice( realPosition ).each(function( siblingControl, i ) {
2314                      siblingControl.setting.set(
2315                          $.extend(
2316                              {},
2317                              siblingControl.setting(),
2318                              {
2319                                  menu_item_parent: control.params.menu_item_id,
2320                                  position: i
2321                              }
2322                          )
2323                      );
2324                  });
2325  
2326                  // Increase the positions of the parent item's subsequent children to make room for this one.
2327                  _( control.getMenuControl().getMenuItemControls() ).each(function( otherControl ) {
2328                      var otherControlSettingValue, isControlToBeShifted;
2329                      isControlToBeShifted = (
2330                          otherControl.setting().menu_item_parent === parentControl.setting().menu_item_parent &&
2331                          otherControl.setting().position > parentControl.setting().position
2332                      );
2333                      if ( isControlToBeShifted ) {
2334                          otherControlSettingValue = _.clone( otherControl.setting() );
2335                          otherControl.setting.set(
2336                              $.extend(
2337                                  otherControlSettingValue,
2338                                  { position: otherControlSettingValue.position + 1 }
2339                              )
2340                          );
2341                      }
2342                  });
2343  
2344                  // Make this control the following sibling of its parent item.
2345                  settingValue.position = parentControl.setting().position + 1;
2346                  settingValue.menu_item_parent = parentControl.setting().menu_item_parent;
2347                  control.setting.set( settingValue );
2348  
2349              } else if ( 1 === offset ) {
2350                  // Skip moving right an item that doesn't have a previous sibling.
2351                  if ( realPosition === 0 ) {
2352                      return;
2353                  }
2354  
2355                  // Make the control the last child of the previous sibling.
2356                  siblingControl = siblingControls[ realPosition - 1 ];
2357                  settingValue.menu_item_parent = siblingControl.params.menu_item_id;
2358                  settingValue.position = 0;
2359                  _( control.getMenuControl().getMenuItemControls() ).each(function( otherControl ) {
2360                      if ( otherControl.setting().menu_item_parent === settingValue.menu_item_parent ) {
2361                          settingValue.position = Math.max( settingValue.position, otherControl.setting().position );
2362                      }
2363                  });
2364                  settingValue.position += 1;
2365                  control.setting.set( settingValue );
2366              }
2367          }
2368      } );
2369  
2370      /**
2371       * wp.customize.Menus.MenuNameControl
2372       *
2373       * Customizer control for a nav menu's name.
2374       *
2375       * @class    wp.customize.Menus.MenuNameControl
2376       * @augments wp.customize.Control
2377       */
2378      api.Menus.MenuNameControl = api.Control.extend(/** @lends wp.customize.Menus.MenuNameControl.prototype */{
2379  
2380          ready: function() {
2381              var control = this;
2382  
2383              if ( control.setting ) {
2384                  var settingValue = control.setting();
2385  
2386                  control.nameElement = new api.Element( control.container.find( '.menu-name-field' ) );
2387  
2388                  control.nameElement.bind(function( value ) {
2389                      var settingValue = control.setting();
2390                      if ( settingValue && settingValue.name !== value ) {
2391                          settingValue = _.clone( settingValue );
2392                          settingValue.name = value;
2393                          control.setting.set( settingValue );
2394                      }
2395                  });
2396                  if ( settingValue ) {
2397                      control.nameElement.set( settingValue.name );
2398                  }
2399  
2400                  control.setting.bind(function( object ) {
2401                      if ( object ) {
2402                          control.nameElement.set( object.name );
2403                      }
2404                  });
2405              }
2406          }
2407      });
2408  
2409      /**
2410       * wp.customize.Menus.MenuLocationsControl
2411       *
2412       * Customizer control for a nav menu's locations.
2413       *
2414       * @since 4.9.0
2415       * @class    wp.customize.Menus.MenuLocationsControl
2416       * @augments wp.customize.Control
2417       */
2418      api.Menus.MenuLocationsControl = api.Control.extend(/** @lends wp.customize.Menus.MenuLocationsControl.prototype */{
2419  
2420          /**
2421           * Set up the control.
2422           *
2423           * @since 4.9.0
2424           */
2425          ready: function () {
2426              var control = this;
2427  
2428              control.container.find( '.assigned-menu-location' ).each(function() {
2429                  var container = $( this ),
2430                      checkbox = container.find( 'input[type=checkbox]' ),
2431                      element = new api.Element( checkbox ),
2432                      navMenuLocationSetting = api( 'nav_menu_locations[' + checkbox.data( 'location-id' ) + ']' ),
2433                      isNewMenu = control.params.menu_id === '',
2434                      updateCheckbox = isNewMenu ? _.noop : function( checked ) {
2435                          element.set( checked );
2436                      },
2437                      updateSetting = isNewMenu ? _.noop : function( checked ) {
2438                          navMenuLocationSetting.set( checked ? control.params.menu_id : 0 );
2439                      },
2440                      updateSelectedMenuLabel = function( selectedMenuId ) {
2441                          var menuSetting = api( 'nav_menu[' + String( selectedMenuId ) + ']' );
2442                          if ( ! selectedMenuId || ! menuSetting || ! menuSetting() ) {
2443                              container.find( '.theme-location-set' ).hide();
2444                          } else {
2445                              container.find( '.theme-location-set' ).show().find( 'span' ).text( displayNavMenuName( menuSetting().name ) );
2446                          }
2447                      };
2448  
2449                  updateCheckbox( navMenuLocationSetting.get() === control.params.menu_id );
2450  
2451                  checkbox.on( 'change', function() {
2452                      // Note: We can't use element.bind( function( checked ){ ... } ) here because it will trigger a change as well.
2453                      updateSetting( this.checked );
2454                  } );
2455  
2456                  navMenuLocationSetting.bind( function( selectedMenuId ) {
2457                      updateCheckbox( selectedMenuId === control.params.menu_id );
2458                      updateSelectedMenuLabel( selectedMenuId );
2459                  } );
2460                  updateSelectedMenuLabel( navMenuLocationSetting.get() );
2461              });
2462          },
2463  
2464          /**
2465           * Set the selected locations.
2466           *
2467           * This method sets the selected locations and allows us to do things like
2468           * set the default location for a new menu.
2469           *
2470           * @since 4.9.0
2471           *
2472           * @param {Object.<string,boolean>} selections - A map of location selections.
2473           * @return {void}
2474           */
2475          setSelections: function( selections ) {
2476              this.container.find( '.menu-location' ).each( function( i, checkboxNode ) {
2477                  var locationId = checkboxNode.dataset.locationId;
2478                  checkboxNode.checked = locationId in selections ? selections[ locationId ] : false;
2479              } );
2480          }
2481      });
2482  
2483      /**
2484       * wp.customize.Menus.MenuAutoAddControl
2485       *
2486       * Customizer control for a nav menu's auto add.
2487       *
2488       * @class    wp.customize.Menus.MenuAutoAddControl
2489       * @augments wp.customize.Control
2490       */
2491      api.Menus.MenuAutoAddControl = api.Control.extend(/** @lends wp.customize.Menus.MenuAutoAddControl.prototype */{
2492  
2493          ready: function() {
2494              var control = this,
2495                  settingValue = control.setting();
2496  
2497              /*
2498               * Since the control is not registered in PHP, we need to prevent the
2499               * preview's sending of the activeControls to result in this control
2500               * being deactivated.
2501               */
2502              control.active.validate = function() {
2503                  var value, section = api.section( control.section() );
2504                  if ( section ) {
2505                      value = section.active();
2506                  } else {
2507                      value = false;
2508                  }
2509                  return value;
2510              };
2511  
2512              control.autoAddElement = new api.Element( control.container.find( 'input[type=checkbox].auto_add' ) );
2513  
2514              control.autoAddElement.bind(function( value ) {
2515                  var settingValue = control.setting();
2516                  if ( settingValue && settingValue.name !== value ) {
2517                      settingValue = _.clone( settingValue );
2518                      settingValue.auto_add = value;
2519                      control.setting.set( settingValue );
2520                  }
2521              });
2522              if ( settingValue ) {
2523                  control.autoAddElement.set( settingValue.auto_add );
2524              }
2525  
2526              control.setting.bind(function( object ) {
2527                  if ( object ) {
2528                      control.autoAddElement.set( object.auto_add );
2529                  }
2530              });
2531          }
2532  
2533      });
2534  
2535      /**
2536       * wp.customize.Menus.MenuControl
2537       *
2538       * Customizer control for menus.
2539       * Note that 'nav_menu' must match the WP_Menu_Customize_Control::$type
2540       *
2541       * @class    wp.customize.Menus.MenuControl
2542       * @augments wp.customize.Control
2543       */
2544      api.Menus.MenuControl = api.Control.extend(/** @lends wp.customize.Menus.MenuControl.prototype */{
2545          /**
2546           * Set up the control.
2547           */
2548          ready: function() {
2549              var control = this,
2550                  section = api.section( control.section() ),
2551                  menuId = control.params.menu_id,
2552                  menu = control.setting(),
2553                  name,
2554                  widgetTemplate,
2555                  select;
2556  
2557              if ( 'undefined' === typeof this.params.menu_id ) {
2558                  throw new Error( 'params.menu_id was not defined' );
2559              }
2560  
2561              /*
2562               * Since the control is not registered in PHP, we need to prevent the
2563               * preview's sending of the activeControls to result in this control
2564               * being deactivated.
2565               */
2566              control.active.validate = function() {
2567                  var value;
2568                  if ( section ) {
2569                      value = section.active();
2570                  } else {
2571                      value = false;
2572                  }
2573                  return value;
2574              };
2575  
2576              control.$controlSection = section.headContainer;
2577              control.$sectionContent = control.container.closest( '.accordion-section-content' );
2578  
2579              this._setupModel();
2580  
2581              api.section( control.section(), function( section ) {
2582                  section.deferred.initSortables.done(function( menuList ) {
2583                      control._setupSortable( menuList );
2584                  });
2585              } );
2586  
2587              this._setupAddition();
2588              this._setupTitle();
2589  
2590              // Add menu to Navigation Menu widgets.
2591              if ( menu ) {
2592                  name = displayNavMenuName( menu.name );
2593  
2594                  // Add the menu to the existing controls.
2595                  api.control.each( function( widgetControl ) {
2596                      if ( ! widgetControl.extended( api.controlConstructor.widget_form ) || 'nav_menu' !== widgetControl.params.widget_id_base ) {
2597                          return;
2598                      }
2599                      widgetControl.container.find( '.nav-menu-widget-form-controls:first' ).show();
2600                      widgetControl.container.find( '.nav-menu-widget-no-menus-message:first' ).hide();
2601  
2602                      select = widgetControl.container.find( 'select' );
2603                      if ( 0 === select.find( 'option[value=' + String( menuId ) + ']' ).length ) {
2604                          select.append( new Option( name, menuId ) );
2605                      }
2606                  } );
2607  
2608                  // Add the menu to the widget template.
2609                  widgetTemplate = $( '#available-widgets-list .widget-tpl:has( input.id_base[ value=nav_menu ] )' );
2610                  widgetTemplate.find( '.nav-menu-widget-form-controls:first' ).show();
2611                  widgetTemplate.find( '.nav-menu-widget-no-menus-message:first' ).hide();
2612                  select = widgetTemplate.find( '.widget-inside select:first' );
2613                  if ( 0 === select.find( 'option[value=' + String( menuId ) + ']' ).length ) {
2614                      select.append( new Option( name, menuId ) );
2615                  }
2616              }
2617  
2618              /*
2619               * Wait for menu items to be added.
2620               * Ideally, we'd bind to an event indicating construction is complete,
2621               * but deferring appears to be the best option today.
2622               */
2623              _.defer( function () {
2624                  control.updateInvitationVisibility();
2625              } );
2626          },
2627  
2628          /**
2629           * Update ordering of menu item controls when the setting is updated.
2630           */
2631          _setupModel: function() {
2632              var control = this,
2633                  menuId = control.params.menu_id;
2634  
2635              control.setting.bind( function( to ) {
2636                  var name;
2637                  if ( false === to ) {
2638                      control._handleDeletion();
2639                  } else {
2640                      // Update names in the Navigation Menu widgets.
2641                      name = displayNavMenuName( to.name );
2642                      api.control.each( function( widgetControl ) {
2643                          if ( ! widgetControl.extended( api.controlConstructor.widget_form ) || 'nav_menu' !== widgetControl.params.widget_id_base ) {
2644                              return;
2645                          }
2646                          var select = widgetControl.container.find( 'select' );
2647                          select.find( 'option[value=' + String( menuId ) + ']' ).text( name );
2648                      });
2649                  }
2650              } );
2651          },
2652  
2653          /**
2654           * Allow items in each menu to be re-ordered, and for the order to be previewed.
2655           *
2656           * Notice that the UI aspects here are handled by wpNavMenu.initSortables()
2657           * which is called in MenuSection.onChangeExpanded()
2658           *
2659           * @param {Object} menuList - The element that has sortable().
2660           */
2661          _setupSortable: function( menuList ) {
2662              var control = this;
2663  
2664              if ( ! menuList.is( control.$sectionContent ) ) {
2665                  throw new Error( 'Unexpected menuList.' );
2666              }
2667  
2668              menuList.on( 'sortstart', function() {
2669                  control.isSorting = true;
2670              });
2671  
2672              menuList.on( 'sortstop', function() {
2673                  setTimeout( function() { // Next tick.
2674                      var menuItemContainerIds = control.$sectionContent.sortable( 'toArray' ),
2675                          menuItemControls = [],
2676                          position = 0,
2677                          priority = 10;
2678  
2679                      control.isSorting = false;
2680  
2681                      // Reset horizontal scroll position when done dragging.
2682                      control.$sectionContent.scrollLeft( 0 );
2683  
2684                      _.each( menuItemContainerIds, function( menuItemContainerId ) {
2685                          var menuItemId, menuItemControl, matches;
2686                          matches = menuItemContainerId.match( /^customize-control-nav_menu_item-(-?\d+)$/, '' );
2687                          if ( ! matches ) {
2688                              return;
2689                          }
2690                          menuItemId = parseInt( matches[1], 10 );
2691                          menuItemControl = api.control( 'nav_menu_item[' + String( menuItemId ) + ']' );
2692                          if ( menuItemControl ) {
2693                              menuItemControls.push( menuItemControl );
2694                          }
2695                      } );
2696  
2697                      _.each( menuItemControls, function( menuItemControl ) {
2698                          if ( false === menuItemControl.setting() ) {
2699                              // Skip deleted items.
2700                              return;
2701                          }
2702                          var setting = _.clone( menuItemControl.setting() );
2703                          position += 1;
2704                          priority += 1;
2705                          setting.position = position;
2706                          menuItemControl.priority( priority );
2707  
2708                          // Note that wpNavMenu will be setting this .menu-item-data-parent-id input's value.
2709                          setting.menu_item_parent = parseInt( menuItemControl.container.find( '.menu-item-data-parent-id' ).val(), 10 );
2710                          if ( ! setting.menu_item_parent ) {
2711                              setting.menu_item_parent = 0;
2712                          }
2713  
2714                          menuItemControl.setting.set( setting );
2715                      });
2716                  });
2717  
2718              });
2719              control.isReordering = false;
2720  
2721              /**
2722               * Keyboard-accessible reordering.
2723               */
2724              this.container.find( '.reorder-toggle' ).on( 'click', function() {
2725                  control.toggleReordering( ! control.isReordering );
2726              } );
2727          },
2728  
2729          /**
2730           * Set up UI for adding a new menu item.
2731           */
2732          _setupAddition: function() {
2733              var self = this;
2734  
2735              this.container.find( '.add-new-menu-item' ).on( 'click', function( event ) {
2736                  if ( self.$sectionContent.hasClass( 'reordering' ) ) {
2737                      return;
2738                  }
2739  
2740                  if ( ! $( 'body' ).hasClass( 'adding-menu-items' ) ) {
2741                      $( this ).attr( 'aria-expanded', 'true' );
2742                      api.Menus.availableMenuItemsPanel.open( self );
2743                  } else {
2744                      $( this ).attr( 'aria-expanded', 'false' );
2745                      api.Menus.availableMenuItemsPanel.close();
2746                      event.stopPropagation();
2747                  }
2748              } );
2749          },
2750  
2751          _handleDeletion: function() {
2752              var control = this,
2753                  section,
2754                  menuId = control.params.menu_id,
2755                  removeSection,
2756                  widgetTemplate,
2757                  navMenuCount = 0;
2758              section = api.section( control.section() );
2759              removeSection = function() {
2760                  section.container.remove();
2761                  api.section.remove( section.id );
2762              };
2763  
2764              if ( section && section.expanded() ) {
2765                  section.collapse({
2766                      completeCallback: function() {
2767                          removeSection();
2768                          wp.a11y.speak( api.Menus.data.l10n.menuDeleted );
2769                          api.panel( 'nav_menus' ).focus();
2770                      }
2771                  });
2772              } else {
2773                  removeSection();
2774              }
2775  
2776              api.each(function( setting ) {
2777                  if ( /^nav_menu\[/.test( setting.id ) && false !== setting() ) {
2778                      navMenuCount += 1;
2779                  }
2780              });
2781  
2782              // Remove the menu from any Navigation Menu widgets.
2783              api.control.each(function( widgetControl ) {
2784                  if ( ! widgetControl.extended( api.controlConstructor.widget_form ) || 'nav_menu' !== widgetControl.params.widget_id_base ) {
2785                      return;
2786                  }
2787                  var select = widgetControl.container.find( 'select' );
2788                  if ( select.val() === String( menuId ) ) {
2789                      select.prop( 'selectedIndex', 0 ).trigger( 'change' );
2790                  }
2791  
2792                  widgetControl.container.find( '.nav-menu-widget-form-controls:first' ).toggle( 0 !== navMenuCount );
2793                  widgetControl.container.find( '.nav-menu-widget-no-menus-message:first' ).toggle( 0 === navMenuCount );
2794                  widgetControl.container.find( 'option[value=' + String( menuId ) + ']' ).remove();
2795              });
2796  
2797              // Remove the menu to the nav menu widget template.
2798              widgetTemplate = $( '#available-widgets-list .widget-tpl:has( input.id_base[ value=nav_menu ] )' );
2799              widgetTemplate.find( '.nav-menu-widget-form-controls:first' ).toggle( 0 !== navMenuCount );
2800              widgetTemplate.find( '.nav-menu-widget-no-menus-message:first' ).toggle( 0 === navMenuCount );
2801              widgetTemplate.find( 'option[value=' + String( menuId ) + ']' ).remove();
2802          },
2803  
2804          /**
2805           * Update Section Title as menu name is changed.
2806           */
2807          _setupTitle: function() {
2808              var control = this;
2809  
2810              control.setting.bind( function( menu ) {
2811                  if ( ! menu ) {
2812                      return;
2813                  }
2814  
2815                  var section = api.section( control.section() ),
2816                      menuId = control.params.menu_id,
2817                      controlTitle = section.headContainer.find( '.accordion-section-title' ),
2818                      sectionTitle = section.contentContainer.find( '.customize-section-title h3' ),
2819                      location = section.headContainer.find( '.menu-in-location' ),
2820                      action = sectionTitle.find( '.customize-action' ),
2821                      name = displayNavMenuName( menu.name );
2822  
2823                  // Update the control title.
2824                  controlTitle.text( name );
2825                  if ( location.length ) {
2826                      location.appendTo( controlTitle );
2827                  }
2828  
2829                  // Update the section title.
2830                  sectionTitle.text( name );
2831                  if ( action.length ) {
2832                      action.prependTo( sectionTitle );
2833                  }
2834  
2835                  // Update the nav menu name in location selects.
2836                  api.control.each( function( control ) {
2837                      if ( /^nav_menu_locations\[/.test( control.id ) ) {
2838                          control.container.find( 'option[value=' + menuId + ']' ).text( name );
2839                      }
2840                  } );
2841  
2842                  // Update the nav menu name in all location checkboxes.
2843                  section.contentContainer.find( '.customize-control-checkbox input' ).each( function() {
2844                      if ( $( this ).prop( 'checked' ) ) {
2845                          $( '.current-menu-location-name-' + $( this ).data( 'location-id' ) ).text( name );
2846                      }
2847                  } );
2848              } );
2849          },
2850  
2851          /***********************************************************************
2852           * Begin public API methods
2853           **********************************************************************/
2854  
2855          /**
2856           * Enable/disable the reordering UI
2857           *
2858           * @param {boolean} showOrHide to enable/disable reordering
2859           */
2860          toggleReordering: function( showOrHide ) {
2861              var addNewItemBtn = this.container.find( '.add-new-menu-item' ),
2862                  reorderBtn = this.container.find( '.reorder-toggle' ),
2863                  itemsTitle = this.$sectionContent.find( '.item-title' );
2864  
2865              showOrHide = Boolean( showOrHide );
2866  
2867              if ( showOrHide === this.$sectionContent.hasClass( 'reordering' ) ) {
2868                  return;
2869              }
2870  
2871              this.isReordering = showOrHide;
2872              this.$sectionContent.toggleClass( 'reordering', showOrHide );
2873              this.$sectionContent.sortable( this.isReordering ? 'disable' : 'enable' );
2874              if ( this.isReordering ) {
2875                  addNewItemBtn.attr({ 'tabindex': '-1', 'aria-hidden': 'true' });
2876                  reorderBtn.attr( 'aria-label', api.Menus.data.l10n.reorderLabelOff );
2877                  wp.a11y.speak( api.Menus.data.l10n.reorderModeOn );
2878                  itemsTitle.attr( 'aria-hidden', 'false' );
2879              } else {
2880                  addNewItemBtn.removeAttr( 'tabindex aria-hidden' );
2881                  reorderBtn.attr( 'aria-label', api.Menus.data.l10n.reorderLabelOn );
2882                  wp.a11y.speak( api.Menus.data.l10n.reorderModeOff );
2883                  itemsTitle.attr( 'aria-hidden', 'true' );
2884              }
2885  
2886              if ( showOrHide ) {
2887                  _( this.getMenuItemControls() ).each( function( formControl ) {
2888                      formControl.collapseForm();
2889                  } );
2890              }
2891          },
2892  
2893          /**
2894           * @return {wp.customize.controlConstructor.nav_menu_item[]}
2895           */
2896          getMenuItemControls: function() {
2897              var menuControl = this,
2898                  menuItemControls = [],
2899                  menuTermId = menuControl.params.menu_id;
2900  
2901              api.control.each(function( control ) {
2902                  if ( 'nav_menu_item' === control.params.type && control.setting() && menuTermId === control.setting().nav_menu_term_id ) {
2903                      menuItemControls.push( control );
2904                  }
2905              });
2906  
2907              return menuItemControls;
2908          },
2909  
2910          /**
2911           * Make sure that each menu item control has the proper depth.
2912           */
2913          reflowMenuItems: function() {
2914              var menuControl = this,
2915                  menuItemControls = menuControl.getMenuItemControls(),
2916                  reflowRecursively;
2917  
2918              reflowRecursively = function( context ) {
2919                  var currentMenuItemControls = [],
2920                      thisParent = context.currentParent;
2921                  _.each( context.menuItemControls, function( menuItemControl ) {
2922                      if ( thisParent === menuItemControl.setting().menu_item_parent ) {
2923                          currentMenuItemControls.push( menuItemControl );
2924                          // @todo We could remove this item from menuItemControls now, for efficiency.
2925                      }
2926                  });
2927                  currentMenuItemControls.sort( function( a, b ) {
2928                      return a.setting().position - b.setting().position;
2929                  });
2930  
2931                  _.each( currentMenuItemControls, function( menuItemControl ) {
2932                      // Update position.
2933                      context.currentAbsolutePosition += 1;
2934                      menuItemControl.priority.set( context.currentAbsolutePosition ); // This will change the sort order.
2935  
2936                      // Update depth.
2937                      if ( ! menuItemControl.container.hasClass( 'menu-item-depth-' + String( context.currentDepth ) ) ) {
2938                          _.each( menuItemControl.container.prop( 'className' ).match( /menu-item-depth-\d+/g ), function( className ) {
2939                              menuItemControl.container.removeClass( className );
2940                          });
2941                          menuItemControl.container.addClass( 'menu-item-depth-' + String( context.currentDepth ) );
2942                      }
2943                      menuItemControl.container.data( 'item-depth', context.currentDepth );
2944  
2945                      // Process any children items.
2946                      context.currentDepth += 1;
2947                      context.currentParent = menuItemControl.params.menu_item_id;
2948                      reflowRecursively( context );
2949                      context.currentDepth -= 1;
2950                      context.currentParent = thisParent;
2951                  });
2952  
2953                  // Update class names for reordering controls.
2954                  if ( currentMenuItemControls.length ) {
2955                      _( currentMenuItemControls ).each(function( menuItemControl ) {
2956                          menuItemControl.container.removeClass( 'move-up-disabled move-down-disabled move-left-disabled move-right-disabled' );
2957                          if ( 0 === context.currentDepth ) {
2958                              menuItemControl.container.addClass( 'move-left-disabled' );
2959                          } else if ( 10 === context.currentDepth ) {
2960                              menuItemControl.container.addClass( 'move-right-disabled' );
2961                          }
2962                      });
2963  
2964                      currentMenuItemControls[0].container
2965                          .addClass( 'move-up-disabled' )
2966                          .addClass( 'move-right-disabled' )
2967                          .toggleClass( 'move-down-disabled', 1 === currentMenuItemControls.length );
2968                      currentMenuItemControls[ currentMenuItemControls.length - 1 ].container
2969                          .addClass( 'move-down-disabled' )
2970                          .toggleClass( 'move-up-disabled', 1 === currentMenuItemControls.length );
2971                  }
2972              };
2973  
2974              reflowRecursively( {
2975                  menuItemControls: menuItemControls,
2976                  currentParent: 0,
2977                  currentDepth: 0,
2978                  currentAbsolutePosition: 0
2979              } );
2980  
2981              menuControl.updateInvitationVisibility( menuItemControls );
2982              menuControl.container.find( '.reorder-toggle' ).toggle( menuItemControls.length > 1 );
2983          },
2984  
2985          /**
2986           * Note that this function gets debounced so that when a lot of setting
2987           * changes are made at once, for instance when moving a menu item that
2988           * has child items, this function will only be called once all of the
2989           * settings have been updated.
2990           */
2991          debouncedReflowMenuItems: _.debounce( function() {
2992              this.reflowMenuItems.apply( this, arguments );
2993          }, 0 ),
2994  
2995          /**
2996           * Add a new item to this menu.
2997           *
2998           * @param {Object} item - Value for the nav_menu_item setting to be created.
2999           * @return {wp.customize.Menus.controlConstructor.nav_menu_item} The newly-created nav_menu_item control instance.
3000           */
3001          addItemToMenu: function( item ) {
3002              var menuControl = this, customizeId, settingArgs, setting, menuItemControl, placeholderId, position = 0, priority = 10,
3003                  originalItemId = item.id || '';
3004  
3005              _.each( menuControl.getMenuItemControls(), function( control ) {
3006                  if ( false === control.setting() ) {
3007                      return;
3008                  }
3009                  priority = Math.max( priority, control.priority() );
3010                  if ( 0 === control.setting().menu_item_parent ) {
3011                      position = Math.max( position, control.setting().position );
3012                  }
3013              });
3014              position += 1;
3015              priority += 1;
3016  
3017              item = $.extend(
3018                  {},
3019                  api.Menus.data.defaultSettingValues.nav_menu_item,
3020                  item,
3021                  {
3022                      nav_menu_term_id: menuControl.params.menu_id,
3023                      original_title: item.title,
3024                      position: position
3025                  }
3026              );
3027              delete item.id; // Only used by Backbone.
3028  
3029              placeholderId = api.Menus.generatePlaceholderAutoIncrementId();
3030              customizeId = 'nav_menu_item[' + String( placeholderId ) + ']';
3031              settingArgs = {
3032                  type: 'nav_menu_item',
3033                  transport: api.Menus.data.settingTransport,
3034                  previewer: api.previewer
3035              };
3036              setting = api.create( customizeId, customizeId, {}, settingArgs );
3037              setting.set( item ); // Change from initial empty object to actual item to mark as dirty.
3038  
3039              // Add the menu item control.
3040              menuItemControl = new api.controlConstructor.nav_menu_item( customizeId, {
3041                  type: 'nav_menu_item',
3042                  section: menuControl.id,
3043                  priority: priority,
3044                  settings: {
3045                      'default': customizeId
3046                  },
3047                  menu_item_id: placeholderId,
3048                  original_item_id: originalItemId
3049              } );
3050  
3051              api.control.add( menuItemControl );
3052              setting.preview();
3053              menuControl.debouncedReflowMenuItems();
3054  
3055              wp.a11y.speak( api.Menus.data.l10n.itemAdded );
3056  
3057              return menuItemControl;
3058          },
3059  
3060          /**
3061           * Show an invitation to add new menu items when there are no menu items.
3062           *
3063           * @since 4.9.0
3064           *
3065           * @param {wp.customize.controlConstructor.nav_menu_item[]} optionalMenuItemControls
3066           */
3067          updateInvitationVisibility: function ( optionalMenuItemControls ) {
3068              var menuItemControls = optionalMenuItemControls || this.getMenuItemControls();
3069  
3070              this.container.find( '.new-menu-item-invitation' ).toggle( menuItemControls.length === 0 );
3071          }
3072      } );
3073  
3074      /**
3075       * Extends wp.customize.controlConstructor with control constructor for
3076       * menu_location, menu_item, nav_menu, and new_menu.
3077       */
3078      $.extend( api.controlConstructor, {
3079          nav_menu_location: api.Menus.MenuLocationControl,
3080          nav_menu_item: api.Menus.MenuItemControl,
3081          nav_menu: api.Menus.MenuControl,
3082          nav_menu_name: api.Menus.MenuNameControl,
3083          nav_menu_locations: api.Menus.MenuLocationsControl,
3084          nav_menu_auto_add: api.Menus.MenuAutoAddControl
3085      });
3086  
3087      /**
3088       * Extends wp.customize.panelConstructor with section constructor for menus.
3089       */
3090      $.extend( api.panelConstructor, {
3091          nav_menus: api.Menus.MenusPanel
3092      });
3093  
3094      /**
3095       * Extends wp.customize.sectionConstructor with section constructor for menu.
3096       */
3097      $.extend( api.sectionConstructor, {
3098          nav_menu: api.Menus.MenuSection,
3099          new_menu: api.Menus.NewMenuSection
3100      });
3101  
3102      /**
3103       * Init Customizer for menus.
3104       */
3105      api.bind( 'ready', function() {
3106  
3107          // Set up the menu items panel.
3108          api.Menus.availableMenuItemsPanel = new api.Menus.AvailableMenuItemsPanelView({
3109              collection: api.Menus.availableMenuItems
3110          });
3111  
3112          api.bind( 'saved', function( data ) {
3113              if ( data.nav_menu_updates || data.nav_menu_item_updates ) {
3114                  api.Menus.applySavedData( data );
3115              }
3116          } );
3117  
3118          /*
3119           * Reset the list of posts created in the customizer once published.
3120           * The setting is updated quietly (bypassing events being triggered)
3121           * so that the customized state doesn't become immediately dirty.
3122           */
3123          api.state( 'changesetStatus' ).bind( function( status ) {
3124              if ( 'publish' === status ) {
3125                  api( 'nav_menus_created_posts' )._value = [];
3126              }
3127          } );
3128  
3129          // Open and focus menu control.
3130          api.previewer.bind( 'focus-nav-menu-item-control', api.Menus.focusMenuItemControl );
3131      } );
3132  
3133      /**
3134       * When customize_save comes back with a success, make sure any inserted
3135       * nav menus and items are properly re-added with their newly-assigned IDs.
3136       *
3137       * @alias wp.customize.Menus.applySavedData
3138       *
3139       * @param {Object} data
3140       * @param {Array} data.nav_menu_updates
3141       * @param {Array} data.nav_menu_item_updates
3142       */
3143      api.Menus.applySavedData = function( data ) {
3144  
3145          var insertedMenuIdMapping = {}, insertedMenuItemIdMapping = {};
3146  
3147          _( data.nav_menu_updates ).each(function( update ) {
3148              var oldCustomizeId, newCustomizeId, customizeId, oldSetting, newSetting, setting, settingValue, oldSection, newSection, wasSaved, widgetTemplate, navMenuCount, shouldExpandNewSection;
3149              if ( 'inserted' === update.status ) {
3150                  if ( ! update.previous_term_id ) {
3151                      throw new Error( 'Expected previous_term_id' );
3152                  }
3153                  if ( ! update.term_id ) {
3154                      throw new Error( 'Expected term_id' );
3155                  }
3156                  oldCustomizeId = 'nav_menu[' + String( update.previous_term_id ) + ']';
3157                  if ( ! api.has( oldCustomizeId ) ) {
3158                      throw new Error( 'Expected setting to exist: ' + oldCustomizeId );
3159                  }
3160                  oldSetting = api( oldCustomizeId );
3161                  if ( ! api.section.has( oldCustomizeId ) ) {
3162                      throw new Error( 'Expected control to exist: ' + oldCustomizeId );
3163                  }
3164                  oldSection = api.section( oldCustomizeId );
3165  
3166                  settingValue = oldSetting.get();
3167                  if ( ! settingValue ) {
3168                      throw new Error( 'Did not expect setting to be empty (deleted).' );
3169                  }
3170                  settingValue = $.extend( _.clone( settingValue ), update.saved_value );
3171  
3172                  insertedMenuIdMapping[ update.previous_term_id ] = update.term_id;
3173                  newCustomizeId = 'nav_menu[' + String( update.term_id ) + ']';
3174                  newSetting = api.create( newCustomizeId, newCustomizeId, settingValue, {
3175                      type: 'nav_menu',
3176                      transport: api.Menus.data.settingTransport,
3177                      previewer: api.previewer
3178                  } );
3179  
3180                  shouldExpandNewSection = oldSection.expanded();
3181                  if ( shouldExpandNewSection ) {
3182                      oldSection.collapse();
3183                  }
3184  
3185                  // Add the menu section.
3186                  newSection = new api.Menus.MenuSection( newCustomizeId, {
3187                      panel: 'nav_menus',
3188                      title: settingValue.name,
3189                      customizeAction: api.Menus.data.l10n.customizingMenus,
3190                      type: 'nav_menu',
3191                      priority: oldSection.priority.get(),
3192                      menu_id: update.term_id
3193                  } );
3194  
3195                  // Add new control for the new menu.
3196                  api.section.add( newSection );
3197  
3198                  // Update the values for nav menus in Navigation Menu controls.
3199                  api.control.each( function( setting ) {
3200                      if ( ! setting.extended( api.controlConstructor.widget_form ) || 'nav_menu' !== setting.params.widget_id_base ) {
3201                          return;
3202                      }
3203                      var select, oldMenuOption, newMenuOption;
3204                      select = setting.container.find( 'select' );
3205                      oldMenuOption = select.find( 'option[value=' + String( update.previous_term_id ) + ']' );
3206                      newMenuOption = select.find( 'option[value=' + String( update.term_id ) + ']' );
3207                      newMenuOption.prop( 'selected', oldMenuOption.prop( 'selected' ) );
3208                      oldMenuOption.remove();
3209                  } );
3210  
3211                  // Delete the old placeholder nav_menu.
3212                  oldSetting.callbacks.disable(); // Prevent setting triggering Customizer dirty state when set.
3213                  oldSetting.set( false );
3214                  oldSetting.preview();
3215                  newSetting.preview();
3216                  oldSetting._dirty = false;
3217  
3218                  // Remove nav_menu section.
3219                  oldSection.container.remove();
3220                  api.section.remove( oldCustomizeId );
3221  
3222                  // Update the nav_menu widget to reflect removed placeholder menu.
3223                  navMenuCount = 0;
3224                  api.each(function( setting ) {
3225                      if ( /^nav_menu\[/.test( setting.id ) && false !== setting() ) {
3226                          navMenuCount += 1;
3227                      }
3228                  });
3229                  widgetTemplate = $( '#available-widgets-list .widget-tpl:has( input.id_base[ value=nav_menu ] )' );
3230                  widgetTemplate.find( '.nav-menu-widget-form-controls:first' ).toggle( 0 !== navMenuCount );
3231                  widgetTemplate.find( '.nav-menu-widget-no-menus-message:first' ).toggle( 0 === navMenuCount );
3232                  widgetTemplate.find( 'option[value=' + String( update.previous_term_id ) + ']' ).remove();
3233  
3234                  // Update the nav_menu_locations[...] controls to remove the placeholder menus from the dropdown options.
3235                  wp.customize.control.each(function( control ){
3236                      if ( /^nav_menu_locations\[/.test( control.id ) ) {
3237                          control.container.find( 'option[value=' + String( update.previous_term_id ) + ']' ).remove();
3238                      }
3239                  });
3240  
3241                  // Update nav_menu_locations to reference the new ID.
3242                  api.each( function( setting ) {
3243                      var wasSaved = api.state( 'saved' ).get();
3244                      if ( /^nav_menu_locations\[/.test( setting.id ) && setting.get() === update.previous_term_id ) {
3245                          setting.set( update.term_id );
3246                          setting._dirty = false; // Not dirty because this is has also just been done on server in WP_Customize_Nav_Menu_Setting::update().
3247                          api.state( 'saved' ).set( wasSaved );
3248                          setting.preview();
3249                      }
3250                  } );
3251  
3252                  if ( shouldExpandNewSection ) {
3253                      newSection.expand();
3254                  }
3255              } else if ( 'updated' === update.status ) {
3256                  customizeId = 'nav_menu[' + String( update.term_id ) + ']';
3257                  if ( ! api.has( customizeId ) ) {
3258                      throw new Error( 'Expected setting to exist: ' + customizeId );
3259                  }
3260  
3261                  // Make sure the setting gets updated with its sanitized server value (specifically the conflict-resolved name).
3262                  setting = api( customizeId );
3263                  if ( ! _.isEqual( update.saved_value, setting.get() ) ) {
3264                      wasSaved = api.state( 'saved' ).get();
3265                      setting.set( update.saved_value );
3266                      setting._dirty = false;
3267                      api.state( 'saved' ).set( wasSaved );
3268                  }
3269              }
3270          } );
3271  
3272          // Build up mapping of nav_menu_item placeholder IDs to inserted IDs.
3273          _( data.nav_menu_item_updates ).each(function( update ) {
3274              if ( update.previous_post_id ) {
3275                  insertedMenuItemIdMapping[ update.previous_post_id ] = update.post_id;
3276              }
3277          });
3278  
3279          _( data.nav_menu_item_updates ).each(function( update ) {
3280              var oldCustomizeId, newCustomizeId, oldSetting, newSetting, settingValue, oldControl, newControl;
3281              if ( 'inserted' === update.status ) {
3282                  if ( ! update.previous_post_id ) {
3283                      throw new Error( 'Expected previous_post_id' );
3284                  }
3285                  if ( ! update.post_id ) {
3286                      throw new Error( 'Expected post_id' );
3287                  }
3288                  oldCustomizeId = 'nav_menu_item[' + String( update.previous_post_id ) + ']';
3289                  if ( ! api.has( oldCustomizeId ) ) {
3290                      throw new Error( 'Expected setting to exist: ' + oldCustomizeId );
3291                  }
3292                  oldSetting = api( oldCustomizeId );
3293                  if ( ! api.control.has( oldCustomizeId ) ) {
3294                      throw new Error( 'Expected control to exist: ' + oldCustomizeId );
3295                  }
3296                  oldControl = api.control( oldCustomizeId );
3297  
3298                  settingValue = oldSetting.get();
3299                  if ( ! settingValue ) {
3300                      throw new Error( 'Did not expect setting to be empty (deleted).' );
3301                  }
3302                  settingValue = _.clone( settingValue );
3303  
3304                  // If the parent menu item was also inserted, update the menu_item_parent to the new ID.
3305                  if ( settingValue.menu_item_parent < 0 ) {
3306                      if ( ! insertedMenuItemIdMapping[ settingValue.menu_item_parent ] ) {
3307                          throw new Error( 'inserted ID for menu_item_parent not available' );
3308                      }
3309                      settingValue.menu_item_parent = insertedMenuItemIdMapping[ settingValue.menu_item_parent ];
3310                  }
3311  
3312                  // If the menu was also inserted, then make sure it uses the new menu ID for nav_menu_term_id.
3313                  if ( insertedMenuIdMapping[ settingValue.nav_menu_term_id ] ) {
3314                      settingValue.nav_menu_term_id = insertedMenuIdMapping[ settingValue.nav_menu_term_id ];
3315                  }
3316  
3317                  newCustomizeId = 'nav_menu_item[' + String( update.post_id ) + ']';
3318                  newSetting = api.create( newCustomizeId, newCustomizeId, settingValue, {
3319                      type: 'nav_menu_item',
3320                      transport: api.Menus.data.settingTransport,
3321                      previewer: api.previewer
3322                  } );
3323  
3324                  // Add the menu control.
3325                  newControl = new api.controlConstructor.nav_menu_item( newCustomizeId, {
3326                      type: 'nav_menu_item',
3327                      menu_id: update.post_id,
3328                      section: 'nav_menu[' + String( settingValue.nav_menu_term_id ) + ']',
3329                      priority: oldControl.priority.get(),
3330                      settings: {
3331                          'default': newCustomizeId
3332                      },
3333                      menu_item_id: update.post_id
3334                  } );
3335  
3336                  // Remove old control.
3337                  oldControl.container.remove();
3338                  api.control.remove( oldCustomizeId );
3339  
3340                  // Add new control to take its place.
3341                  api.control.add( newControl );
3342  
3343                  // Delete the placeholder and preview the new setting.
3344                  oldSetting.callbacks.disable(); // Prevent setting triggering Customizer dirty state when set.
3345                  oldSetting.set( false );
3346                  oldSetting.preview();
3347                  newSetting.preview();
3348                  oldSetting._dirty = false;
3349  
3350                  newControl.container.toggleClass( 'menu-item-edit-inactive', oldControl.container.hasClass( 'menu-item-edit-inactive' ) );
3351              }
3352          });
3353  
3354          /*
3355           * Update the settings for any nav_menu widgets that had selected a placeholder ID.
3356           */
3357          _.each( data.widget_nav_menu_updates, function( widgetSettingValue, widgetSettingId ) {
3358              var setting = api( widgetSettingId );
3359              if ( setting ) {
3360                  setting._value = widgetSettingValue;
3361                  setting.preview(); // Send to the preview now so that menu refresh will use the inserted menu.
3362              }
3363          });
3364      };
3365  
3366      /**
3367       * Focus a menu item control.
3368       *
3369       * @alias wp.customize.Menus.focusMenuItemControl
3370       *
3371       * @param {string} menuItemId
3372       */
3373      api.Menus.focusMenuItemControl = function( menuItemId ) {
3374          var control = api.Menus.getMenuItemControl( menuItemId );
3375          if ( control ) {
3376              control.focus();
3377          }
3378      };
3379  
3380      /**
3381       * Get the control for a given menu.
3382       *
3383       * @alias wp.customize.Menus.getMenuControl
3384       *
3385       * @param menuId
3386       * @return {wp.customize.controlConstructor.menus[]}
3387       */
3388      api.Menus.getMenuControl = function( menuId ) {
3389          return api.control( 'nav_menu[' + menuId + ']' );
3390      };
3391  
3392      /**
3393       * Given a menu item ID, get the control associated with it.
3394       *
3395       * @alias wp.customize.Menus.getMenuItemControl
3396       *
3397       * @param {string} menuItemId
3398       * @return {Object|null}
3399       */
3400      api.Menus.getMenuItemControl = function( menuItemId ) {
3401          return api.control( menuItemIdToSettingId( menuItemId ) );
3402      };
3403  
3404      /**
3405       * @alias wp.customize.Menus~menuItemIdToSettingId
3406       *
3407       * @param {string} menuItemId
3408       */
3409  	function menuItemIdToSettingId( menuItemId ) {
3410          return 'nav_menu_item[' + menuItemId + ']';
3411      }
3412  
3413      /**
3414       * Apply sanitize_text_field()-like logic to the supplied name, returning a
3415       * "unnammed" fallback string if the name is then empty.
3416       *
3417       * @alias wp.customize.Menus~displayNavMenuName
3418       *
3419       * @param {string} name
3420       * @return {string}
3421       */
3422  	function displayNavMenuName( name ) {
3423          name = name || '';
3424          name = wp.sanitize.stripTagsAndEncodeText( name ); // Remove any potential tags from name.
3425          name = name.toString().trim();
3426          return name || api.Menus.data.l10n.unnamed;
3427      }
3428  
3429  })( wp.customize, wp, jQuery );