wp-includes/js/media-models.js

   1 (function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o<r.length;o++)s(r[o]);return s})({1:[function(require,module,exports){
   2 /*globals wp, _, jQuery */
   3
   4 var $ = jQuery,
   5         Attachment, Attachments, l10n, media;
   6
   7 window.wp = window.wp || {};
   8
   9 /**
  10  * Create and return a media frame.
  11  *
  12  * Handles the default media experience.
  13  *
  14  * @param  {object} attributes The properties passed to the main media controller.
  15  * @return {wp.media.view.MediaFrame} A media workflow.
  16  */
  17 media = wp.media = function( attributes ) {
  18         var MediaFrame = media.view.MediaFrame,
  19                 frame;
  20
  21         if ( ! MediaFrame ) {
  22                 return;
  23         }
  24
  25         attributes = _.defaults( attributes || {}, {
  26                 frame: 'select'
  27         });
  28
  29         if ( 'select' === attributes.frame && MediaFrame.Select ) {
  30                 frame = new MediaFrame.Select( attributes );
  31         } else if ( 'post' === attributes.frame && MediaFrame.Post ) {
  32                 frame = new MediaFrame.Post( attributes );
  33         } else if ( 'manage' === attributes.frame && MediaFrame.Manage ) {
  34                 frame = new MediaFrame.Manage( attributes );
  35         } else if ( 'image' === attributes.frame && MediaFrame.ImageDetails ) {
  36                 frame = new MediaFrame.ImageDetails( attributes );
  37         } else if ( 'audio' === attributes.frame && MediaFrame.AudioDetails ) {
  38                 frame = new MediaFrame.AudioDetails( attributes );
  39         } else if ( 'video' === attributes.frame && MediaFrame.VideoDetails ) {
  40                 frame = new MediaFrame.VideoDetails( attributes );
  41         } else if ( 'edit-attachments' === attributes.frame && MediaFrame.EditAttachments ) {
  42                 frame = new MediaFrame.EditAttachments( attributes );
  43         }
  44
  45         delete attributes.frame;
  46
  47         media.frame = frame;
  48
  49         return frame;
  50 };
  51
  52 _.extend( media, { model: {}, view: {}, controller: {}, frames: {} });
  53
  54 // Link any localized strings.
  55 l10n = media.model.l10n = window._wpMediaModelsL10n || {};
  56
  57 // Link any settings.
  58 media.model.settings = l10n.settings || {};
  59 delete l10n.settings;
  60
  61 Attachment = media.model.Attachment = require( './models/attachment.js' );
  62 Attachments = media.model.Attachments = require( './models/attachments.js' );
  63
  64 media.model.Query = require( './models/query.js' );
  65 media.model.PostImage = require( './models/post-image.js' );
  66 media.model.Selection = require( './models/selection.js' );
  67
  68 /**
  69  * ========================================================================
  70  * UTILITIES
  71  * ========================================================================
  72  */
  73
  74 /**
  75  * A basic equality comparator for Backbone models.
  76  *
  77  * Used to order models within a collection - @see wp.media.model.Attachments.comparator().
  78  *
  79  * @param  {mixed}  a  The primary parameter to compare.
  80  * @param  {mixed}  b  The primary parameter to compare.
  81  * @param  {string} ac The fallback parameter to compare, a's cid.
  82  * @param  {string} bc The fallback parameter to compare, b's cid.
  83  * @return {number}    -1: a should come before b.
  84  *                      0: a and b are of the same rank.
  85  *                      1: b should come before a.
  86  */
  87 media.compare = function( a, b, ac, bc ) {
  88         if ( _.isEqual( a, b ) ) {
  89                 return ac === bc ? 0 : (ac > bc ? -1 : 1);
  90         } else {
  91                 return a > b ? -1 : 1;
  92         }
  93 };
  94
  95 _.extend( media, {
  96         /**
  97          * media.template( id )
  98          *
  99          * Fetch a JavaScript template for an id, and return a templating function for it.
 100          *
 101          * See wp.template() in `wp-includes/js/wp-util.js`.
 102          *
 103          * @borrows wp.template as template
 104          */
 105         template: wp.template,
 106
 107         /**
 108          * media.post( [action], [data] )
 109          *
 110          * Sends a POST request to WordPress.
 111          * See wp.ajax.post() in `wp-includes/js/wp-util.js`.
 112          *
 113          * @borrows wp.ajax.post as post
 114          */
 115         post: wp.ajax.post,
 116
 117         /**
 118          * media.ajax( [action], [options] )
 119          *
 120          * Sends an XHR request to WordPress.
 121          * See wp.ajax.send() in `wp-includes/js/wp-util.js`.
 122          *
 123          * @borrows wp.ajax.send as ajax
 124          */
 125         ajax: wp.ajax.send,
 126
 127         /**
 128          * Scales a set of dimensions to fit within bounding dimensions.
 129          *
 130          * @param {Object} dimensions
 131          * @returns {Object}
 132          */
 133         fit: function( dimensions ) {
 134                 var width     = dimensions.width,
 135                         height    = dimensions.height,
 136                         maxWidth  = dimensions.maxWidth,
 137                         maxHeight = dimensions.maxHeight,
 138                         constraint;
 139
 140                 // Compare ratios between the two values to determine which
 141                 // max to constrain by. If a max value doesn't exist, then the
 142                 // opposite side is the constraint.
 143                 if ( ! _.isUndefined( maxWidth ) && ! _.isUndefined( maxHeight ) ) {
 144                         constraint = ( width / height > maxWidth / maxHeight ) ? 'width' : 'height';
 145                 } else if ( _.isUndefined( maxHeight ) ) {
 146                         constraint = 'width';
 147                 } else if (  _.isUndefined( maxWidth ) && height > maxHeight ) {
 148                         constraint = 'height';
 149                 }
 150
 151                 // If the value of the constrained side is larger than the max,
 152                 // then scale the values. Otherwise return the originals; they fit.
 153                 if ( 'width' === constraint && width > maxWidth ) {
 154                         return {
 155                                 width : maxWidth,
 156                                 height: Math.round( maxWidth * height / width )
 157                         };
 158                 } else if ( 'height' === constraint && height > maxHeight ) {
 159                         return {
 160                                 width : Math.round( maxHeight * width / height ),
 161                                 height: maxHeight
 162                         };
 163                 } else {
 164                         return {
 165                                 width : width,
 166                                 height: height
 167                         };
 168                 }
 169         },
 170         /**
 171          * Truncates a string by injecting an ellipsis into the middle.
 172          * Useful for filenames.
 173          *
 174          * @param {String} string
 175          * @param {Number} [length=30]
 176          * @param {String} [replacement=&hellip;]
 177          * @returns {String} The string, unless length is greater than string.length.
 178          */
 179         truncate: function( string, length, replacement ) {
 180                 length = length || 30;
 181                 replacement = replacement || '&hellip;';
 182
 183                 if ( string.length <= length ) {
 184                         return string;
 185                 }
 186
 187                 return string.substr( 0, length / 2 ) + replacement + string.substr( -1 * length / 2 );
 188         }
 189 });
 190
 191 /**
 192  * ========================================================================
 193  * MODELS
 194  * ========================================================================
 195  */
 196 /**
 197  * wp.media.attachment
 198  *
 199  * @static
 200  * @param {String} id A string used to identify a model.
 201  * @returns {wp.media.model.Attachment}
 202  */
 203 media.attachment = function( id ) {
 204         return Attachment.get( id );
 205 };
 206
 207 /**
 208  * A collection of all attachments that have been fetched from the server.
 209  *
 210  * @static
 211  * @member {wp.media.model.Attachments}
 212  */
 213 Attachments.all = new Attachments();
 214
 215 /**
 216  * wp.media.query
 217  *
 218  * Shorthand for creating a new Attachments Query.
 219  *
 220  * @param {object} [props]
 221  * @returns {wp.media.model.Attachments}
 222  */
 223 media.query = function( props ) {
 224         return new Attachments( null, {
 225                 props: _.extend( _.defaults( props || {}, { orderby: 'date' } ), { query: true } )
 226         });
 227 };
 228
 229 // Clean up. Prevents mobile browsers caching
 230 $(window).on('unload', function(){
 231         window.wp = null;
 232 });
 233
 234 },{"./models/attachment.js":2,"./models/attachments.js":3,"./models/post-image.js":4,"./models/query.js":5,"./models/selection.js":6}],2:[function(require,module,exports){
 235 /*globals wp, _, Backbone */
 236
 237 /**
 238  * wp.media.model.Attachment
 239  *
 240  * @class
 241  * @augments Backbone.Model
 242  */
 243 var $ = Backbone.$,
 244         Attachment;
 245
 246 Attachment = Backbone.Model.extend({
 247         /**
 248          * Triggered when attachment details change
 249          * Overrides Backbone.Model.sync
 250          *
 251          * @param {string} method
 252          * @param {wp.media.model.Attachment} model
 253          * @param {Object} [options={}]
 254          *
 255          * @returns {Promise}
 256          */
 257         sync: function( method, model, options ) {
 258                 // If the attachment does not yet have an `id`, return an instantly
 259                 // rejected promise. Otherwise, all of our requests will fail.
 260                 if ( _.isUndefined( this.id ) ) {
 261                         return $.Deferred().rejectWith( this ).promise();
 262                 }
 263
 264                 // Overload the `read` request so Attachment.fetch() functions correctly.
 265                 if ( 'read' === method ) {
 266                         options = options || {};
 267                         options.context = this;
 268                         options.data = _.extend( options.data || {}, {
 269                                 action: 'get-attachment',
 270                                 id: this.id
 271                         });
 272                         return wp.media.ajax( options );
 273
 274                 // Overload the `update` request so properties can be saved.
 275                 } else if ( 'update' === method ) {
 276                         // If we do not have the necessary nonce, fail immeditately.
 277                         if ( ! this.get('nonces') || ! this.get('nonces').update ) {
 278                                 return $.Deferred().rejectWith( this ).promise();
 279                         }
 280
 281                         options = options || {};
 282                         options.context = this;
 283
 284                         // Set the action and ID.
 285                         options.data = _.extend( options.data || {}, {
 286                                 action:  'save-attachment',
 287                                 id:      this.id,
 288                                 nonce:   this.get('nonces').update,
 289                                 post_id: wp.media.model.settings.post.id
 290                         });
 291
 292                         // Record the values of the changed attributes.
 293                         if ( model.hasChanged() ) {
 294                                 options.data.changes = {};
 295
 296                                 _.each( model.changed, function( value, key ) {
 297                                         options.data.changes[ key ] = this.get( key );
 298                                 }, this );
 299                         }
 300
 301                         return wp.media.ajax( options );
 302
 303                 // Overload the `delete` request so attachments can be removed.
 304                 // This will permanently delete an attachment.
 305                 } else if ( 'delete' === method ) {
 306                         options = options || {};
 307
 308                         if ( ! options.wait ) {
 309                                 this.destroyed = true;
 310                         }
 311
 312                         options.context = this;
 313                         options.data = _.extend( options.data || {}, {
 314                                 action:   'delete-post',
 315                                 id:       this.id,
 316                                 _wpnonce: this.get('nonces')['delete']
 317                         });
 318
 319                         return wp.media.ajax( options ).done( function() {
 320                                 this.destroyed = true;
 321                         }).fail( function() {
 322                                 this.destroyed = false;
 323                         });
 324
 325                 // Otherwise, fall back to `Backbone.sync()`.
 326                 } else {
 327                         /**
 328                          * Call `sync` directly on Backbone.Model
 329                          */
 330                         return Backbone.Model.prototype.sync.apply( this, arguments );
 331                 }
 332         },
 333         /**
 334          * Convert date strings into Date objects.
 335          *
 336          * @param {Object} resp The raw response object, typically returned by fetch()
 337          * @returns {Object} The modified response object, which is the attributes hash
 338          *    to be set on the model.
 339          */
 340         parse: function( resp ) {
 341                 if ( ! resp ) {
 342                         return resp;
 343                 }
 344
 345                 resp.date = new Date( resp.date );
 346                 resp.modified = new Date( resp.modified );
 347                 return resp;
 348         },
 349         /**
 350          * @param {Object} data The properties to be saved.
 351          * @param {Object} options Sync options. e.g. patch, wait, success, error.
 352          *
 353          * @this Backbone.Model
 354          *
 355          * @returns {Promise}
 356          */
 357         saveCompat: function( data, options ) {
 358                 var model = this;
 359
 360                 // If we do not have the necessary nonce, fail immeditately.
 361                 if ( ! this.get('nonces') || ! this.get('nonces').update ) {
 362                         return $.Deferred().rejectWith( this ).promise();
 363                 }
 364
 365                 return wp.media.post( 'save-attachment-compat', _.defaults({
 366                         id:      this.id,
 367                         nonce:   this.get('nonces').update,
 368                         post_id: wp.media.model.settings.post.id
 369                 }, data ) ).done( function( resp, status, xhr ) {
 370                         model.set( model.parse( resp, xhr ), options );
 371                 });
 372         }
 373 }, {
 374         /**
 375          * Create a new model on the static 'all' attachments collection and return it.
 376          *
 377          * @static
 378          * @param {Object} attrs
 379          * @returns {wp.media.model.Attachment}
 380          */
 381         create: function( attrs ) {
 382                 var Attachments = wp.media.model.Attachments;
 383                 return Attachments.all.push( attrs );
 384         },
 385         /**
 386          * Create a new model on the static 'all' attachments collection and return it.
 387          *
 388          * If this function has already been called for the id,
 389          * it returns the specified attachment.
 390          *
 391          * @static
 392          * @param {string} id A string used to identify a model.
 393          * @param {Backbone.Model|undefined} attachment
 394          * @returns {wp.media.model.Attachment}
 395          */
 396         get: _.memoize( function( id, attachment ) {
 397                 var Attachments = wp.media.model.Attachments;
 398                 return Attachments.all.push( attachment || { id: id } );
 399         })
 400 });
 401
 402 module.exports = Attachment;
 403
 404 },{}],3:[function(require,module,exports){
 405 /*globals wp, _, Backbone */
 406
 407 /**
 408  * wp.media.model.Attachments
 409  *
 410  * A collection of attachments.
 411  *
 412  * This collection has no persistence with the server without supplying
 413  * 'options.props.query = true', which will mirror the collection
 414  * to an Attachments Query collection - @see wp.media.model.Attachments.mirror().
 415  *
 416  * @class
 417  * @augments Backbone.Collection
 418  *
 419  * @param {array}  [models]                Models to initialize with the collection.
 420  * @param {object} [options]               Options hash for the collection.
 421  * @param {string} [options.props]         Options hash for the initial query properties.
 422  * @param {string} [options.props.order]   Initial order (ASC or DESC) for the collection.
 423  * @param {string} [options.props.orderby] Initial attribute key to order the collection by.
 424  * @param {string} [options.props.query]   Whether the collection is linked to an attachments query.
 425  * @param {string} [options.observe]
 426  * @param {string} [options.filters]
 427  *
 428  */
 429 var Attachments = Backbone.Collection.extend({
 430         /**
 431          * @type {wp.media.model.Attachment}
 432          */
 433         model: wp.media.model.Attachment,
 434         /**
 435          * @param {Array} [models=[]] Array of models used to populate the collection.
 436          * @param {Object} [options={}]
 437          */
 438         initialize: function( models, options ) {
 439                 options = options || {};
 440
 441                 this.props   = new Backbone.Model();
 442                 this.filters = options.filters || {};
 443
 444                 // Bind default `change` events to the `props` model.
 445                 this.props.on( 'change', this._changeFilteredProps, this );
 446
 447                 this.props.on( 'change:order',   this._changeOrder,   this );
 448                 this.props.on( 'change:orderby', this._changeOrderby, this );
 449                 this.props.on( 'change:query',   this._changeQuery,   this );
 450
 451                 this.props.set( _.defaults( options.props || {} ) );
 452
 453                 if ( options.observe ) {
 454                         this.observe( options.observe );
 455                 }
 456         },
 457         /**
 458          * Sort the collection when the order attribute changes.
 459          *
 460          * @access private
 461          */
 462         _changeOrder: function() {
 463                 if ( this.comparator ) {
 464                         this.sort();
 465                 }
 466         },
 467         /**
 468          * Set the default comparator only when the `orderby` property is set.
 469          *
 470          * @access private
 471          *
 472          * @param {Backbone.Model} model
 473          * @param {string} orderby
 474          */
 475         _changeOrderby: function( model, orderby ) {
 476                 // If a different comparator is defined, bail.
 477                 if ( this.comparator && this.comparator !== Attachments.comparator ) {
 478                         return;
 479                 }
 480
 481                 if ( orderby && 'post__in' !== orderby ) {
 482                         this.comparator = Attachments.comparator;
 483                 } else {
 484                         delete this.comparator;
 485                 }
 486         },
 487         /**
 488          * If the `query` property is set to true, query the server using
 489          * the `props` values, and sync the results to this collection.
 490          *
 491          * @access private
 492          *
 493          * @param {Backbone.Model} model
 494          * @param {Boolean} query
 495          */
 496         _changeQuery: function( model, query ) {
 497                 if ( query ) {
 498                         this.props.on( 'change', this._requery, this );
 499                         this._requery();
 500                 } else {
 501                         this.props.off( 'change', this._requery, this );
 502                 }
 503         },
 504         /**
 505          * @access private
 506          *
 507          * @param {Backbone.Model} model
 508          */
 509         _changeFilteredProps: function( model ) {
 510                 // If this is a query, updating the collection will be handled by
 511                 // `this._requery()`.
 512                 if ( this.props.get('query') ) {
 513                         return;
 514                 }
 515
 516                 var changed = _.chain( model.changed ).map( function( t, prop ) {
 517                         var filter = Attachments.filters[ prop ],
 518                                 term = model.get( prop );
 519
 520                         if ( ! filter ) {
 521                                 return;
 522                         }
 523
 524                         if ( term && ! this.filters[ prop ] ) {
 525                                 this.filters[ prop ] = filter;
 526                         } else if ( ! term && this.filters[ prop ] === filter ) {
 527                                 delete this.filters[ prop ];
 528                         } else {
 529                                 return;
 530                         }
 531
 532                         // Record the change.
 533                         return true;
 534                 }, this ).any().value();
 535
 536                 if ( ! changed ) {
 537                         return;
 538                 }
 539
 540                 // If no `Attachments` model is provided to source the searches
 541                 // from, then automatically generate a source from the existing
 542                 // models.
 543                 if ( ! this._source ) {
 544                         this._source = new Attachments( this.models );
 545                 }
 546
 547                 this.reset( this._source.filter( this.validator, this ) );
 548         },
 549
 550         validateDestroyed: false,
 551         /**
 552          * Checks whether an attachment is valid.
 553          *
 554          * @param {wp.media.model.Attachment} attachment
 555          * @returns {Boolean}
 556          */
 557         validator: function( attachment ) {
 558                 if ( ! this.validateDestroyed && attachment.destroyed ) {
 559                         return false;
 560                 }
 561                 return _.all( this.filters, function( filter ) {
 562                         return !! filter.call( this, attachment );
 563                 }, this );
 564         },
 565         /**
 566          * Add or remove an attachment to the collection depending on its validity.
 567          *
 568          * @param {wp.media.model.Attachment} attachment
 569          * @param {Object} options
 570          * @returns {wp.media.model.Attachments} Returns itself to allow chaining
 571          */
 572         validate: function( attachment, options ) {
 573                 var valid = this.validator( attachment ),
 574                         hasAttachment = !! this.get( attachment.cid );
 575
 576                 if ( ! valid && hasAttachment ) {
 577                         this.remove( attachment, options );
 578                 } else if ( valid && ! hasAttachment ) {
 579                         this.add( attachment, options );
 580                 }
 581
 582                 return this;
 583         },
 584
 585         /**
 586          * Add or remove all attachments from another collection depending on each one's validity.
 587          *
 588          * @param {wp.media.model.Attachments} attachments
 589          * @param {object} [options={}]
 590          *
 591          * @fires wp.media.model.Attachments#reset
 592          *
 593          * @returns {wp.media.model.Attachments} Returns itself to allow chaining
 594          */
 595         validateAll: function( attachments, options ) {
 596                 options = options || {};
 597
 598                 _.each( attachments.models, function( attachment ) {
 599                         this.validate( attachment, { silent: true });
 600                 }, this );
 601
 602                 if ( ! options.silent ) {
 603                         this.trigger( 'reset', this, options );
 604                 }
 605                 return this;
 606         },
 607         /**
 608          * Start observing another attachments collection change events
 609          * and replicate them on this collection.
 610          *
 611          * @param {wp.media.model.Attachments} The attachments collection to observe.
 612          * @returns {wp.media.model.Attachments} Returns itself to allow chaining.
 613          */
 614         observe: function( attachments ) {
 615                 this.observers = this.observers || [];
 616                 this.observers.push( attachments );
 617
 618                 attachments.on( 'add change remove', this._validateHandler, this );
 619                 attachments.on( 'reset', this._validateAllHandler, this );
 620                 this.validateAll( attachments );
 621                 return this;
 622         },
 623         /**
 624          * Stop replicating collection change events from another attachments collection.
 625          *
 626          * @param {wp.media.model.Attachments} The attachments collection to stop observing.
 627          * @returns {wp.media.model.Attachments} Returns itself to allow chaining
 628          */
 629         unobserve: function( attachments ) {
 630                 if ( attachments ) {
 631                         attachments.off( null, null, this );
 632                         this.observers = _.without( this.observers, attachments );
 633
 634                 } else {
 635                         _.each( this.observers, function( attachments ) {
 636                                 attachments.off( null, null, this );
 637                         }, this );
 638                         delete this.observers;
 639                 }
 640
 641                 return this;
 642         },
 643         /**
 644          * @access private
 645          *
 646          * @param {wp.media.model.Attachments} attachment
 647          * @param {wp.media.model.Attachments} attachments
 648          * @param {Object} options
 649          *
 650          * @returns {wp.media.model.Attachments} Returns itself to allow chaining
 651          */
 652         _validateHandler: function( attachment, attachments, options ) {
 653                 // If we're not mirroring this `attachments` collection,
 654                 // only retain the `silent` option.
 655                 options = attachments === this.mirroring ? options : {
 656                         silent: options && options.silent
 657                 };
 658
 659                 return this.validate( attachment, options );
 660         },
 661         /**
 662          * @access private
 663          *
 664          * @param {wp.media.model.Attachments} attachments
 665          * @param {Object} options
 666          * @returns {wp.media.model.Attachments} Returns itself to allow chaining
 667          */
 668         _validateAllHandler: function( attachments, options ) {
 669                 return this.validateAll( attachments, options );
 670         },
 671         /**
 672          * Start mirroring another attachments collection, clearing out any models already
 673          * in the collection.
 674          *
 675          * @param {wp.media.model.Attachments} The attachments collection to mirror.
 676          * @returns {wp.media.model.Attachments} Returns itself to allow chaining
 677          */
 678         mirror: function( attachments ) {
 679                 if ( this.mirroring && this.mirroring === attachments ) {
 680                         return this;
 681                 }
 682
 683                 this.unmirror();
 684                 this.mirroring = attachments;
 685
 686                 // Clear the collection silently. A `reset` event will be fired
 687                 // when `observe()` calls `validateAll()`.
 688                 this.reset( [], { silent: true } );
 689                 this.observe( attachments );
 690
 691                 return this;
 692         },
 693         /**
 694          * Stop mirroring another attachments collection.
 695          */
 696         unmirror: function() {
 697                 if ( ! this.mirroring ) {
 698                         return;
 699                 }
 700
 701                 this.unobserve( this.mirroring );
 702                 delete this.mirroring;
 703         },
 704         /**
 705          * Retrive more attachments from the server for the collection.
 706          *
 707          * Only works if the collection is mirroring a Query Attachments collection,
 708          * and forwards to its `more` method. This collection class doesn't have
 709          * server persistence by itself.
 710          *
 711          * @param {object} options
 712          * @returns {Promise}
 713          */
 714         more: function( options ) {
 715                 var deferred = jQuery.Deferred(),
 716                         mirroring = this.mirroring,
 717                         attachments = this;
 718
 719                 if ( ! mirroring || ! mirroring.more ) {
 720                         return deferred.resolveWith( this ).promise();
 721                 }
 722                 // If we're mirroring another collection, forward `more` to
 723                 // the mirrored collection. Account for a race condition by
 724                 // checking if we're still mirroring that collection when
 725                 // the request resolves.
 726                 mirroring.more( options ).done( function() {
 727                         if ( this === attachments.mirroring ) {
 728                                 deferred.resolveWith( this );
 729                         }
 730                 });
 731
 732                 return deferred.promise();
 733         },
 734         /**
 735          * Whether there are more attachments that haven't been sync'd from the server
 736          * that match the collection's query.
 737          *
 738          * Only works if the collection is mirroring a Query Attachments collection,
 739          * and forwards to its `hasMore` method. This collection class doesn't have
 740          * server persistence by itself.
 741          *
 742          * @returns {boolean}
 743          */
 744         hasMore: function() {
 745                 return this.mirroring ? this.mirroring.hasMore() : false;
 746         },
 747         /**
 748          * A custom AJAX-response parser.
 749          *
 750          * See trac ticket #24753
 751          *
 752          * @param {Object|Array} resp The raw response Object/Array.
 753          * @param {Object} xhr
 754          * @returns {Array} The array of model attributes to be added to the collection
 755          */
 756         parse: function( resp, xhr ) {
 757                 if ( ! _.isArray( resp ) ) {
 758                         resp = [resp];
 759                 }
 760
 761                 return _.map( resp, function( attrs ) {
 762                         var id, attachment, newAttributes;
 763
 764                         if ( attrs instanceof Backbone.Model ) {
 765                                 id = attrs.get( 'id' );
 766                                 attrs = attrs.attributes;
 767                         } else {
 768                                 id = attrs.id;
 769                         }
 770
 771                         attachment = wp.media.model.Attachment.get( id );
 772                         newAttributes = attachment.parse( attrs, xhr );
 773
 774                         if ( ! _.isEqual( attachment.attributes, newAttributes ) ) {
 775                                 attachment.set( newAttributes );
 776                         }
 777
 778                         return attachment;
 779                 });
 780         },
 781         /**
 782          * If the collection is a query, create and mirror an Attachments Query collection.
 783          *
 784          * @access private
 785          */
 786         _requery: function( refresh ) {
 787                 var props;
 788                 if ( this.props.get('query') ) {
 789                         props = this.props.toJSON();
 790                         props.cache = ( true !== refresh );
 791                         this.mirror( wp.media.model.Query.get( props ) );
 792                 }
 793         },
 794         /**
 795          * If this collection is sorted by `menuOrder`, recalculates and saves
 796          * the menu order to the database.
 797          *
 798          * @returns {undefined|Promise}
 799          */
 800         saveMenuOrder: function() {
 801                 if ( 'menuOrder' !== this.props.get('orderby') ) {
 802                         return;
 803                 }
 804
 805                 // Removes any uploading attachments, updates each attachment's
 806                 // menu order, and returns an object with an { id: menuOrder }
 807                 // mapping to pass to the request.
 808                 var attachments = this.chain().filter( function( attachment ) {
 809                         return ! _.isUndefined( attachment.id );
 810                 }).map( function( attachment, index ) {
 811                         // Indices start at 1.
 812                         index = index + 1;
 813                         attachment.set( 'menuOrder', index );
 814                         return [ attachment.id, index ];
 815                 }).object().value();
 816
 817                 if ( _.isEmpty( attachments ) ) {
 818                         return;
 819                 }
 820
 821                 return wp.media.post( 'save-attachment-order', {
 822                         nonce:       wp.media.model.settings.post.nonce,
 823                         post_id:     wp.media.model.settings.post.id,
 824                         attachments: attachments
 825                 });
 826         }
 827 }, {
 828         /**
 829          * A function to compare two attachment models in an attachments collection.
 830          *
 831          * Used as the default comparator for instances of wp.media.model.Attachments
 832          * and its subclasses. @see wp.media.model.Attachments._changeOrderby().
 833          *
 834          * @static
 835          *
 836          * @param {Backbone.Model} a
 837          * @param {Backbone.Model} b
 838          * @param {Object} options
 839          * @returns {Number} -1 if the first model should come before the second,
 840          *    0 if they are of the same rank and
 841          *    1 if the first model should come after.
 842          */
 843         comparator: function( a, b, options ) {
 844                 var key   = this.props.get('orderby'),
 845                         order = this.props.get('order') || 'DESC',
 846                         ac    = a.cid,
 847                         bc    = b.cid;
 848
 849                 a = a.get( key );
 850                 b = b.get( key );
 851
 852                 if ( 'date' === key || 'modified' === key ) {
 853                         a = a || new Date();
 854                         b = b || new Date();
 855                 }
 856
 857                 // If `options.ties` is set, don't enforce the `cid` tiebreaker.
 858                 if ( options && options.ties ) {
 859                         ac = bc = null;
 860                 }
 861
 862                 return ( 'DESC' === order ) ? wp.media.compare( a, b, ac, bc ) : wp.media.compare( b, a, bc, ac );
 863         },
 864         /**
 865          * @namespace
 866          */
 867         filters: {
 868                 /**
 869                  * @static
 870                  * Note that this client-side searching is *not* equivalent
 871                  * to our server-side searching.
 872                  *
 873                  * @param {wp.media.model.Attachment} attachment
 874                  *
 875                  * @this wp.media.model.Attachments
 876                  *
 877                  * @returns {Boolean}
 878                  */
 879                 search: function( attachment ) {
 880                         if ( ! this.props.get('search') ) {
 881                                 return true;
 882                         }
 883
 884                         return _.any(['title','filename','description','caption','name'], function( key ) {
 885                                 var value = attachment.get( key );
 886                                 return value && -1 !== value.search( this.props.get('search') );
 887                         }, this );
 888                 },
 889                 /**
 890                  * @static
 891                  * @param {wp.media.model.Attachment} attachment
 892                  *
 893                  * @this wp.media.model.Attachments
 894                  *
 895                  * @returns {Boolean}
 896                  */
 897                 type: function( attachment ) {
 898                         var type = this.props.get('type');
 899                         return ! type || -1 !== type.indexOf( attachment.get('type') );
 900                 },
 901                 /**
 902                  * @static
 903                  * @param {wp.media.model.Attachment} attachment
 904                  *
 905                  * @this wp.media.model.Attachments
 906                  *
 907                  * @returns {Boolean}
 908                  */
 909                 uploadedTo: function( attachment ) {
 910                         var uploadedTo = this.props.get('uploadedTo');
 911                         if ( _.isUndefined( uploadedTo ) ) {
 912                                 return true;
 913                         }
 914
 915                         return uploadedTo === attachment.get('uploadedTo');
 916                 },
 917                 /**
 918                  * @static
 919                  * @param {wp.media.model.Attachment} attachment
 920                  *
 921                  * @this wp.media.model.Attachments
 922                  *
 923                  * @returns {Boolean}
 924                  */
 925                 status: function( attachment ) {
 926                         var status = this.props.get('status');
 927                         if ( _.isUndefined( status ) ) {
 928                                 return true;
 929                         }
 930
 931                         return status === attachment.get('status');
 932                 }
 933         }
 934 });
 935
 936 module.exports = Attachments;
 937
 938 },{}],4:[function(require,module,exports){
 939 /*globals Backbone */
 940
 941 /**
 942  * wp.media.model.PostImage
 943  *
 944  * An instance of an image that's been embedded into a post.
 945  *
 946  * Used in the embedded image attachment display settings modal - @see wp.media.view.MediaFrame.ImageDetails.
 947  *
 948  * @class
 949  * @augments Backbone.Model
 950  *
 951  * @param {int} [attributes]               Initial model attributes.
 952  * @param {int} [attributes.attachment_id] ID of the attachment.
 953  **/
 954 var PostImage = Backbone.Model.extend({
 955
 956         initialize: function( attributes ) {
 957                 var Attachment = wp.media.model.Attachment;
 958                 this.attachment = false;
 959
 960                 if ( attributes.attachment_id ) {
 961                         this.attachment = Attachment.get( attributes.attachment_id );
 962                         if ( this.attachment.get( 'url' ) ) {
 963                                 this.dfd = jQuery.Deferred();
 964                                 this.dfd.resolve();
 965                         } else {
 966                                 this.dfd = this.attachment.fetch();
 967                         }
 968                         this.bindAttachmentListeners();
 969                 }
 970
 971                 // keep url in sync with changes to the type of link
 972                 this.on( 'change:link', this.updateLinkUrl, this );
 973                 this.on( 'change:size', this.updateSize, this );
 974
 975                 this.setLinkTypeFromUrl();
 976                 this.setAspectRatio();
 977
 978                 this.set( 'originalUrl', attributes.url );
 979         },
 980
 981         bindAttachmentListeners: function() {
 982                 this.listenTo( this.attachment, 'sync', this.setLinkTypeFromUrl );
 983                 this.listenTo( this.attachment, 'sync', this.setAspectRatio );
 984                 this.listenTo( this.attachment, 'change', this.updateSize );
 985         },
 986
 987         changeAttachment: function( attachment, props ) {
 988                 this.stopListening( this.attachment );
 989                 this.attachment = attachment;
 990                 this.bindAttachmentListeners();
 991
 992                 this.set( 'attachment_id', this.attachment.get( 'id' ) );
 993                 this.set( 'caption', this.attachment.get( 'caption' ) );
 994                 this.set( 'alt', this.attachment.get( 'alt' ) );
 995                 this.set( 'size', props.get( 'size' ) );
 996                 this.set( 'align', props.get( 'align' ) );
 997                 this.set( 'link', props.get( 'link' ) );
 998                 this.updateLinkUrl();
 999                 this.updateSize();
1000         },
1001
1002         setLinkTypeFromUrl: function() {
1003                 var linkUrl = this.get( 'linkUrl' ),
1004                         type;
1005
1006                 if ( ! linkUrl ) {
1007                         this.set( 'link', 'none' );
1008                         return;
1009                 }
1010
1011                 // default to custom if there is a linkUrl
1012                 type = 'custom';
1013
1014                 if ( this.attachment ) {
1015                         if ( this.attachment.get( 'url' ) === linkUrl ) {
1016                                 type = 'file';
1017                         } else if ( this.attachment.get( 'link' ) === linkUrl ) {
1018                                 type = 'post';
1019                         }
1020                 } else {
1021                         if ( this.get( 'url' ) === linkUrl ) {
1022                                 type = 'file';
1023                         }
1024                 }
1025
1026                 this.set( 'link', type );
1027         },
1028
1029         updateLinkUrl: function() {
1030                 var link = this.get( 'link' ),
1031                         url;
1032
1033                 switch( link ) {
1034                         case 'file':
1035                                 if ( this.attachment ) {
1036                                         url = this.attachment.get( 'url' );
1037                                 } else {
1038                                         url = this.get( 'url' );
1039                                 }
1040                                 this.set( 'linkUrl', url );
1041                                 break;
1042                         case 'post':
1043                                 this.set( 'linkUrl', this.attachment.get( 'link' ) );
1044                                 break;
1045                         case 'none':
1046                                 this.set( 'linkUrl', '' );
1047                                 break;
1048                 }
1049         },
1050
1051         updateSize: function() {
1052                 var size;
1053
1054                 if ( ! this.attachment ) {
1055                         return;
1056                 }
1057
1058                 if ( this.get( 'size' ) === 'custom' ) {
1059                         this.set( 'width', this.get( 'customWidth' ) );
1060                         this.set( 'height', this.get( 'customHeight' ) );
1061                         this.set( 'url', this.get( 'originalUrl' ) );
1062                         return;
1063                 }
1064
1065                 size = this.attachment.get( 'sizes' )[ this.get( 'size' ) ];
1066
1067                 if ( ! size ) {
1068                         return;
1069                 }
1070
1071                 this.set( 'url', size.url );
1072                 this.set( 'width', size.width );
1073                 this.set( 'height', size.height );
1074         },
1075
1076         setAspectRatio: function() {
1077                 var full;
1078
1079                 if ( this.attachment && this.attachment.get( 'sizes' ) ) {
1080                         full = this.attachment.get( 'sizes' ).full;
1081
1082                         if ( full ) {
1083                                 this.set( 'aspectRatio', full.width / full.height );
1084                                 return;
1085                         }
1086                 }
1087
1088                 this.set( 'aspectRatio', this.get( 'customWidth' ) / this.get( 'customHeight' ) );
1089         }
1090 });
1091
1092 module.exports = PostImage;
1093
1094 },{}],5:[function(require,module,exports){
1095 /*globals wp, _ */
1096
1097 /**
1098  * wp.media.model.Query
1099  *
1100  * A collection of attachments that match the supplied query arguments.
1101  *
1102  * Note: Do NOT change this.args after the query has been initialized.
1103  *       Things will break.
1104  *
1105  * @class
1106  * @augments wp.media.model.Attachments
1107  * @augments Backbone.Collection
1108  *
1109  * @param {array}  [models]                      Models to initialize with the collection.
1110  * @param {object} [options]                     Options hash.
1111  * @param {object} [options.args]                Attachments query arguments.
1112  * @param {object} [options.args.posts_per_page]
1113  */
1114 var Attachments = wp.media.model.Attachments,
1115         Query;
1116
1117 Query = Attachments.extend({
1118         /**
1119          * @global wp.Uploader
1120          *
1121          * @param {array}  [models=[]]  Array of initial models to populate the collection.
1122          * @param {object} [options={}]
1123          */
1124         initialize: function( models, options ) {
1125                 var allowed;
1126
1127                 options = options || {};
1128                 Attachments.prototype.initialize.apply( this, arguments );
1129
1130                 this.args     = options.args;
1131                 this._hasMore = true;
1132                 this.created  = new Date();
1133
1134                 this.filters.order = function( attachment ) {
1135                         var orderby = this.props.get('orderby'),
1136                                 order = this.props.get('order');
1137
1138                         if ( ! this.comparator ) {
1139                                 return true;
1140                         }
1141
1142                         // We want any items that can be placed before the last
1143                         // item in the set. If we add any items after the last
1144                         // item, then we can't guarantee the set is complete.
1145                         if ( this.length ) {
1146                                 return 1 !== this.comparator( attachment, this.last(), { ties: true });
1147
1148                         // Handle the case where there are no items yet and
1149                         // we're sorting for recent items. In that case, we want
1150                         // changes that occurred after we created the query.
1151                         } else if ( 'DESC' === order && ( 'date' === orderby || 'modified' === orderby ) ) {
1152                                 return attachment.get( orderby ) >= this.created;
1153
1154                         // If we're sorting by menu order and we have no items,
1155                         // accept any items that have the default menu order (0).
1156                         } else if ( 'ASC' === order && 'menuOrder' === orderby ) {
1157                                 return attachment.get( orderby ) === 0;
1158                         }
1159
1160                         // Otherwise, we don't want any items yet.
1161                         return false;
1162                 };
1163
1164                 // Observe the central `wp.Uploader.queue` collection to watch for
1165                 // new matches for the query.
1166                 //
1167                 // Only observe when a limited number of query args are set. There
1168                 // are no filters for other properties, so observing will result in
1169                 // false positives in those queries.
1170                 allowed = [ 's', 'order', 'orderby', 'posts_per_page', 'post_mime_type', 'post_parent' ];
1171                 if ( wp.Uploader && _( this.args ).chain().keys().difference( allowed ).isEmpty().value() ) {
1172                         this.observe( wp.Uploader.queue );
1173                 }
1174         },
1175         /**
1176          * Whether there are more attachments that haven't been sync'd from the server
1177          * that match the collection's query.
1178          *
1179          * @returns {boolean}
1180          */
1181         hasMore: function() {
1182                 return this._hasMore;
1183         },
1184         /**
1185          * Fetch more attachments from the server for the collection.
1186          *
1187          * @param   {object}  [options={}]
1188          * @returns {Promise}
1189          */
1190         more: function( options ) {
1191                 var query = this;
1192
1193                 // If there is already a request pending, return early with the Deferred object.
1194                 if ( this._more && 'pending' === this._more.state() ) {
1195                         return this._more;
1196                 }
1197
1198                 if ( ! this.hasMore() ) {
1199                         return jQuery.Deferred().resolveWith( this ).promise();
1200                 }
1201
1202                 options = options || {};
1203                 options.remove = false;
1204
1205                 return this._more = this.fetch( options ).done( function( resp ) {
1206                         if ( _.isEmpty( resp ) || -1 === this.args.posts_per_page || resp.length < this.args.posts_per_page ) {
1207                                 query._hasMore = false;
1208                         }
1209                 });
1210         },
1211         /**
1212          * Overrides Backbone.Collection.sync
1213          * Overrides wp.media.model.Attachments.sync
1214          *
1215          * @param {String} method
1216          * @param {Backbone.Model} model
1217          * @param {Object} [options={}]
1218          * @returns {Promise}
1219          */
1220         sync: function( method, model, options ) {
1221                 var args, fallback;
1222
1223                 // Overload the read method so Attachment.fetch() functions correctly.
1224                 if ( 'read' === method ) {
1225                         options = options || {};
1226                         options.context = this;
1227                         options.data = _.extend( options.data || {}, {
1228                                 action:  'query-attachments',
1229                                 post_id: wp.media.model.settings.post.id
1230                         });
1231
1232                         // Clone the args so manipulation is non-destructive.
1233                         args = _.clone( this.args );
1234
1235                         // Determine which page to query.
1236                         if ( -1 !== args.posts_per_page ) {
1237                                 args.paged = Math.round( this.length / args.posts_per_page ) + 1;
1238                         }
1239
1240                         options.data.query = args;
1241                         return wp.media.ajax( options );
1242
1243                 // Otherwise, fall back to Backbone.sync()
1244                 } else {
1245                         /**
1246                          * Call wp.media.model.Attachments.sync or Backbone.sync
1247                          */
1248                         fallback = Attachments.prototype.sync ? Attachments.prototype : Backbone;
1249                         return fallback.sync.apply( this, arguments );
1250                 }
1251         }
1252 }, {
1253         /**
1254          * @readonly
1255          */
1256         defaultProps: {
1257                 orderby: 'date',
1258                 order:   'DESC'
1259         },
1260         /**
1261          * @readonly
1262          */
1263         defaultArgs: {
1264                 posts_per_page: 40
1265         },
1266         /**
1267          * @readonly
1268          */
1269         orderby: {
1270                 allowed:  [ 'name', 'author', 'date', 'title', 'modified', 'uploadedTo', 'id', 'post__in', 'menuOrder' ],
1271                 /**
1272                  * A map of JavaScript orderby values to their WP_Query equivalents.
1273                  * @type {Object}
1274                  */
1275                 valuemap: {
1276                         'id':         'ID',
1277                         'uploadedTo': 'parent',
1278                         'menuOrder':  'menu_order ID'
1279                 }
1280         },
1281         /**
1282          * A map of JavaScript query properties to their WP_Query equivalents.
1283          *
1284          * @readonly
1285          */
1286         propmap: {
1287                 'search':    's',
1288                 'type':      'post_mime_type',
1289                 'perPage':   'posts_per_page',
1290                 'menuOrder': 'menu_order',
1291                 'uploadedTo': 'post_parent',
1292                 'status':     'post_status',
1293                 'include':    'post__in',
1294                 'exclude':    'post__not_in'
1295         },
1296         /**
1297          * Creates and returns an Attachments Query collection given the properties.
1298          *
1299          * Caches query objects and reuses where possible.
1300          *
1301          * @static
1302          * @method
1303          *
1304          * @param {object} [props]
1305          * @param {Object} [props.cache=true]   Whether to use the query cache or not.
1306          * @param {Object} [props.order]
1307          * @param {Object} [props.orderby]
1308          * @param {Object} [props.include]
1309          * @param {Object} [props.exclude]
1310          * @param {Object} [props.s]
1311          * @param {Object} [props.post_mime_type]
1312          * @param {Object} [props.posts_per_page]
1313          * @param {Object} [props.menu_order]
1314          * @param {Object} [props.post_parent]
1315          * @param {Object} [props.post_status]
1316          * @param {Object} [options]
1317          *
1318          * @returns {wp.media.model.Query} A new Attachments Query collection.
1319          */
1320         get: (function(){
1321                 /**
1322                  * @static
1323                  * @type Array
1324                  */
1325                 var queries = [];
1326
1327                 /**
1328                  * @returns {Query}
1329                  */
1330                 return function( props, options ) {
1331                         var args     = {},
1332                                 orderby  = Query.orderby,
1333                                 defaults = Query.defaultProps,
1334                                 query,
1335                                 cache    = !! props.cache || _.isUndefined( props.cache );
1336
1337                         // Remove the `query` property. This isn't linked to a query,
1338                         // this *is* the query.
1339                         delete props.query;
1340                         delete props.cache;
1341
1342                         // Fill default args.
1343                         _.defaults( props, defaults );
1344
1345                         // Normalize the order.
1346                         props.order = props.order.toUpperCase();
1347                         if ( 'DESC' !== props.order && 'ASC' !== props.order ) {
1348                                 props.order = defaults.order.toUpperCase();
1349                         }
1350
1351                         // Ensure we have a valid orderby value.
1352                         if ( ! _.contains( orderby.allowed, props.orderby ) ) {
1353                                 props.orderby = defaults.orderby;
1354                         }
1355
1356                         _.each( [ 'include', 'exclude' ], function( prop ) {
1357                                 if ( props[ prop ] && ! _.isArray( props[ prop ] ) ) {
1358                                         props[ prop ] = [ props[ prop ] ];
1359                                 }
1360                         } );
1361
1362                         // Generate the query `args` object.
1363                         // Correct any differing property names.
1364                         _.each( props, function( value, prop ) {
1365                                 if ( _.isNull( value ) ) {
1366                                         return;
1367                                 }
1368
1369                                 args[ Query.propmap[ prop ] || prop ] = value;
1370                         });
1371
1372                         // Fill any other default query args.
1373                         _.defaults( args, Query.defaultArgs );
1374
1375                         // `props.orderby` does not always map directly to `args.orderby`.
1376                         // Substitute exceptions specified in orderby.keymap.
1377                         args.orderby = orderby.valuemap[ props.orderby ] || props.orderby;
1378
1379                         // Search the query cache for a matching query.
1380                         if ( cache ) {
1381                                 query = _.find( queries, function( query ) {
1382                                         return _.isEqual( query.args, args );
1383                                 });
1384                         } else {
1385                                 queries = [];
1386                         }
1387
1388                         // Otherwise, create a new query and add it to the cache.
1389                         if ( ! query ) {
1390                                 query = new Query( [], _.extend( options || {}, {
1391                                         props: props,
1392                                         args:  args
1393                                 } ) );
1394                                 queries.push( query );
1395                         }
1396
1397                         return query;
1398                 };
1399         }())
1400 });
1401
1402 module.exports = Query;
1403
1404 },{}],6:[function(require,module,exports){
1405 /*globals wp, _ */
1406
1407 /**
1408  * wp.media.model.Selection
1409  *
1410  * A selection of attachments.
1411  *
1412  * @class
1413  * @augments wp.media.model.Attachments
1414  * @augments Backbone.Collection
1415  */
1416 var Attachments = wp.media.model.Attachments,
1417         Selection;
1418
1419 Selection = Attachments.extend({
1420         /**
1421          * Refresh the `single` model whenever the selection changes.
1422          * Binds `single` instead of using the context argument to ensure
1423          * it receives no parameters.
1424          *
1425          * @param {Array} [models=[]] Array of models used to populate the collection.
1426          * @param {Object} [options={}]
1427          */
1428         initialize: function( models, options ) {
1429                 /**
1430                  * call 'initialize' directly on the parent class
1431                  */
1432                 Attachments.prototype.initialize.apply( this, arguments );
1433                 this.multiple = options && options.multiple;
1434
1435                 this.on( 'add remove reset', _.bind( this.single, this, false ) );
1436         },
1437
1438         /**
1439          * If the workflow does not support multi-select, clear out the selection
1440          * before adding a new attachment to it.
1441          *
1442          * @param {Array} models
1443          * @param {Object} options
1444          * @returns {wp.media.model.Attachment[]}
1445          */
1446         add: function( models, options ) {
1447                 if ( ! this.multiple ) {
1448                         this.remove( this.models );
1449                 }
1450                 /**
1451                  * call 'add' directly on the parent class
1452                  */
1453                 return Attachments.prototype.add.call( this, models, options );
1454         },
1455
1456         /**
1457          * Fired when toggling (clicking on) an attachment in the modal.
1458          *
1459          * @param {undefined|boolean|wp.media.model.Attachment} model
1460          *
1461          * @fires wp.media.model.Selection#selection:single
1462          * @fires wp.media.model.Selection#selection:unsingle
1463          *
1464          * @returns {Backbone.Model}
1465          */
1466         single: function( model ) {
1467                 var previous = this._single;
1468
1469                 // If a `model` is provided, use it as the single model.
1470                 if ( model ) {
1471                         this._single = model;
1472                 }
1473                 // If the single model isn't in the selection, remove it.
1474                 if ( this._single && ! this.get( this._single.cid ) ) {
1475                         delete this._single;
1476                 }
1477
1478                 this._single = this._single || this.last();
1479
1480                 // If single has changed, fire an event.
1481                 if ( this._single !== previous ) {
1482                         if ( previous ) {
1483                                 previous.trigger( 'selection:unsingle', previous, this );
1484
1485                                 // If the model was already removed, trigger the collection
1486                                 // event manually.
1487                                 if ( ! this.get( previous.cid ) ) {
1488                                         this.trigger( 'selection:unsingle', previous, this );
1489                                 }
1490                         }
1491                         if ( this._single ) {
1492                                 this._single.trigger( 'selection:single', this._single, this );
1493                         }
1494                 }
1495
1496                 // Return the single model, or the last model as a fallback.
1497                 return this._single;
1498         }
1499 });
1500
1501 module.exports = Selection;
1502
1503 },{}]},{},[1]);