resources/src/mediawiki.rcfilters/mw.rcfilters.Controller.js

   1 ( function ( mw, $ ) {
   2         /* eslint no-underscore-dangle: "off" */
   3         /**
   4          * Controller for the filters in Recent Changes
   5          *
   6          * @param {mw.rcfilters.dm.FiltersViewModel} filtersModel Filters view model
   7          * @param {mw.rcfilters.dm.ChangesListViewModel} changesListModel Changes list view model
   8          * @param {mw.rcfilters.dm.SavedQueriesModel} savedQueriesModel Saved queries model
   9          */
  10         mw.rcfilters.Controller = function MwRcfiltersController( filtersModel, changesListModel, savedQueriesModel ) {
  11                 this.filtersModel = filtersModel;
  12                 this.changesListModel = changesListModel;
  13                 this.savedQueriesModel = savedQueriesModel;
  14                 this.requestCounter = 0;
  15                 this.baseFilterState = {};
  16                 this.uriProcessor = null;
  17                 this.initializing = false;
  18         };
  19
  20         /* Initialization */
  21         OO.initClass( mw.rcfilters.Controller );
  22
  23         /**
  24          * Initialize the filter and parameter states
  25          *
  26          * @param {Array} filterStructure Filter definition and structure for the model
  27          * @param {Object} [namespaceStructure] Namespace definition
  28          * @param {Object} [tagList] Tag definition
  29          */
  30         mw.rcfilters.Controller.prototype.initialize = function ( filterStructure, namespaceStructure, tagList ) {
  31                 var parsedSavedQueries,
  32                         uri = new mw.Uri(),
  33                         $changesList = $( '.mw-changeslist' ).first().contents();
  34
  35                 // Initialize the model
  36                 this.filtersModel.initializeFilters( filterStructure, namespaceStructure, tagList );
  37
  38                 this._buildBaseFilterState();
  39
  40                 this.uriProcessor = new mw.rcfilters.UriProcessor(
  41                         this.filtersModel
  42                 );
  43
  44                 try {
  45                         parsedSavedQueries = JSON.parse( mw.user.options.get( 'rcfilters-saved-queries' ) || '{}' );
  46                 } catch ( err ) {
  47                         parsedSavedQueries = {};
  48                 }
  49
  50                 // The queries are saved in a minimized state, so we need
  51                 // to send over the base state so the saved queries model
  52                 // can normalize them per each query item
  53                 this.savedQueriesModel.initialize(
  54                         parsedSavedQueries,
  55                         this._getBaseFilterState()
  56                 );
  57
  58                 // Check whether we need to load defaults.
  59                 // We do this by checking whether the current URI query
  60                 // contains any parameters recognized by the system.
  61                 // If it does, we load the given state.
  62                 // If it doesn't, we have no values at all, and we assume
  63                 // the user loads the base-page and we load defaults.
  64                 // Defaults should only be applied on load (if necessary)
  65                 // or on request
  66                 this.initializing = true;
  67                 if (
  68                         this.savedQueriesModel.getDefault() &&
  69                         !this.uriProcessor.doesQueryContainRecognizedParams( uri.query )
  70                 ) {
  71                         // We have defaults from a saved query.
  72                         // We will load them straight-forward (as if
  73                         // they were clicked in the menu) so we trigger
  74                         // a full ajax request and change of URL
  75                         this.applySavedQuery( this.savedQueriesModel.getDefault() );
  76                 } else {
  77                         // There are either recognized parameters in the URL
  78                         // or there are none, but there is also no default
  79                         // saved query (so defaults are from the backend)
  80                         // We want to update the state but not fetch results
  81                         // again
  82                         this.updateStateFromUrl( false );
  83
  84                         // Update the changes list with the existing data
  85                         // so it gets processed
  86                         this.changesListModel.update(
  87                                 $changesList.length ? $changesList : 'NO_RESULTS',
  88                                 $( 'fieldset.rcoptions' ).first()
  89                         );
  90                 }
  91
  92                 this.initializing = false;
  93                 this.switchView( 'default' );
  94         };
  95
  96         /**
  97          * Switch the view of the filters model
  98          *
  99          * @param {string} view Requested view
 100          */
 101         mw.rcfilters.Controller.prototype.switchView = function ( view ) {
 102                 this.filtersModel.switchView( view );
 103         };
 104
 105         /**
 106          * Reset to default filters
 107          */
 108         mw.rcfilters.Controller.prototype.resetToDefaults = function () {
 109                 this.uriProcessor.updateModelBasedOnQuery( this._getDefaultParams() );
 110                 this.updateChangesList();
 111         };
 112
 113         /**
 114          * Empty all selected filters
 115          */
 116         mw.rcfilters.Controller.prototype.emptyFilters = function () {
 117                 var highlightedFilterNames = this.filtersModel
 118                         .getHighlightedItems()
 119                         .map( function ( filterItem ) { return { name: filterItem.getName() }; } );
 120
 121                 this.filtersModel.emptyAllFilters();
 122                 this.filtersModel.clearAllHighlightColors();
 123                 // Check all filter interactions
 124                 this.filtersModel.reassessFilterInteractions();
 125
 126                 this.updateChangesList();
 127
 128                 if ( highlightedFilterNames ) {
 129                         this._trackHighlight( 'clearAll', highlightedFilterNames );
 130                 }
 131         };
 132
 133         /**
 134          * Update the selected state of a filter
 135          *
 136          * @param {string} filterName Filter name
 137          * @param {boolean} [isSelected] Filter selected state
 138          */
 139         mw.rcfilters.Controller.prototype.toggleFilterSelect = function ( filterName, isSelected ) {
 140                 var filterItem = this.filtersModel.getItemByName( filterName );
 141
 142                 if ( !filterItem ) {
 143                         // If no filter was found, break
 144                         return;
 145                 }
 146
 147                 isSelected = isSelected === undefined ? !filterItem.isSelected() : isSelected;
 148
 149                 if ( filterItem.isSelected() !== isSelected ) {
 150                         this.filtersModel.toggleFilterSelected( filterName, isSelected );
 151
 152                         this.updateChangesList();
 153
 154                         // Check filter interactions
 155                         this.filtersModel.reassessFilterInteractions( filterItem );
 156                 }
 157         };
 158
 159         /**
 160          * Clear both highlight and selection of a filter
 161          *
 162          * @param {string} filterName Name of the filter item
 163          */
 164         mw.rcfilters.Controller.prototype.clearFilter = function ( filterName ) {
 165                 var filterItem = this.filtersModel.getItemByName( filterName ),
 166                         isHighlighted = filterItem.isHighlighted();
 167
 168                 if ( filterItem.isSelected() || isHighlighted ) {
 169                         this.filtersModel.clearHighlightColor( filterName );
 170                         this.filtersModel.toggleFilterSelected( filterName, false );
 171                         this.updateChangesList();
 172                         this.filtersModel.reassessFilterInteractions( filterItem );
 173                 }
 174
 175                 if ( isHighlighted ) {
 176                         this._trackHighlight( 'clear', filterName );
 177                 }
 178         };
 179
 180         /**
 181          * Toggle the highlight feature on and off
 182          */
 183         mw.rcfilters.Controller.prototype.toggleHighlight = function () {
 184                 this.filtersModel.toggleHighlight();
 185                 this._updateURL();
 186
 187                 if ( this.filtersModel.isHighlightEnabled() ) {
 188                         mw.hook( 'RcFilters.highlight.enable' ).fire();
 189                 }
 190         };
 191
 192         /**
 193          * Toggle the namespaces inverted feature on and off
 194          */
 195         mw.rcfilters.Controller.prototype.toggleInvertedNamespaces = function () {
 196                 this.filtersModel.toggleInvertedNamespaces();
 197                 this.updateChangesList();
 198         };
 199
 200         /**
 201          * Set the highlight color for a filter item
 202          *
 203          * @param {string} filterName Name of the filter item
 204          * @param {string} color Selected color
 205          */
 206         mw.rcfilters.Controller.prototype.setHighlightColor = function ( filterName, color ) {
 207                 this.filtersModel.setHighlightColor( filterName, color );
 208                 this._updateURL();
 209                 this._trackHighlight( 'set', { name: filterName, color: color } );
 210         };
 211
 212         /**
 213          * Clear highlight for a filter item
 214          *
 215          * @param {string} filterName Name of the filter item
 216          */
 217         mw.rcfilters.Controller.prototype.clearHighlightColor = function ( filterName ) {
 218                 this.filtersModel.clearHighlightColor( filterName );
 219                 this._updateURL();
 220                 this._trackHighlight( 'clear', filterName );
 221         };
 222
 223         /**
 224          * Save the current model state as a saved query
 225          *
 226          * @param {string} [label] Label of the saved query
 227          */
 228         mw.rcfilters.Controller.prototype.saveCurrentQuery = function ( label ) {
 229                 var highlightedItems = {},
 230                         highlightEnabled = this.filtersModel.isHighlightEnabled();
 231
 232                 // Prepare highlights
 233                 this.filtersModel.getHighlightedItems().forEach( function ( item ) {
 234                         highlightedItems[ item.getName() ] = highlightEnabled ?
 235                                 item.getHighlightColor() : null;
 236                 } );
 237                 // These are filter states; highlight is stored as boolean
 238                 highlightedItems.highlight = this.filtersModel.isHighlightEnabled();
 239
 240                 // Add item
 241                 this.savedQueriesModel.addNewQuery(
 242                         label || mw.msg( 'rcfilters-savedqueries-defaultlabel' ),
 243                         {
 244                                 filters: this.filtersModel.getSelectedState(),
 245                                 highlights: highlightedItems,
 246                                 invert: this.filtersModel.areNamespacesInverted()
 247                         }
 248                 );
 249
 250                 // Save item
 251                 this._saveSavedQueries();
 252         };
 253
 254         /**
 255          * Remove a saved query
 256          *
 257          * @param {string} queryID Query id
 258          */
 259         mw.rcfilters.Controller.prototype.removeSavedQuery = function ( queryID ) {
 260                 var query = this.savedQueriesModel.getItemByID( queryID );
 261
 262                 this.savedQueriesModel.removeItems( [ query ] );
 263
 264                 // Check if this item was the default
 265                 if ( this.savedQueriesModel.getDefault() === queryID ) {
 266                         // Nulify the default
 267                         this.savedQueriesModel.setDefault( null );
 268                 }
 269                 this._saveSavedQueries();
 270         };
 271
 272         /**
 273          * Rename a saved query
 274          *
 275          * @param {string} queryID Query id
 276          * @param {string} newLabel New label for the query
 277          */
 278         mw.rcfilters.Controller.prototype.renameSavedQuery = function ( queryID, newLabel ) {
 279                 var queryItem = this.savedQueriesModel.getItemByID( queryID );
 280
 281                 if ( queryItem ) {
 282                         queryItem.updateLabel( newLabel );
 283                 }
 284                 this._saveSavedQueries();
 285         };
 286
 287         /**
 288          * Set a saved query as default
 289          *
 290          * @param {string} queryID Query Id. If null is given, default
 291          *  query is reset.
 292          */
 293         mw.rcfilters.Controller.prototype.setDefaultSavedQuery = function ( queryID ) {
 294                 this.savedQueriesModel.setDefault( queryID );
 295                 this._saveSavedQueries();
 296         };
 297
 298         /**
 299          * Load a saved query
 300          *
 301          * @param {string} queryID Query id
 302          */
 303         mw.rcfilters.Controller.prototype.applySavedQuery = function ( queryID ) {
 304                 var data, highlights,
 305                         queryItem = this.savedQueriesModel.getItemByID( queryID );
 306
 307                 if ( queryItem ) {
 308                         data = queryItem.getData();
 309                         highlights = data.highlights;
 310
 311                         // Backwards compatibility; initial version mispelled 'highlight' with 'highlights'
 312                         highlights.highlight = highlights.highlights || highlights.highlight;
 313
 314                         // Update model state from filters
 315                         this.filtersModel.toggleFiltersSelected( data.filters );
 316
 317                         // Update namespace inverted property
 318                         this.filtersModel.toggleInvertedNamespaces( !!Number( data.invert ) );
 319
 320                         // Update highlight state
 321                         this.filtersModel.toggleHighlight( !!Number( highlights.highlight ) );
 322                         this.filtersModel.getItems().forEach( function ( filterItem ) {
 323                                 var color = highlights[ filterItem.getName() ];
 324                                 if ( color ) {
 325                                         filterItem.setHighlightColor( color );
 326                                 } else {
 327                                         filterItem.clearHighlightColor();
 328                                 }
 329                         } );
 330
 331                         // Check all filter interactions
 332                         this.filtersModel.reassessFilterInteractions();
 333
 334                         this.updateChangesList();
 335                 }
 336         };
 337
 338         /**
 339          * Check whether the current filter and highlight state exists
 340          * in the saved queries model.
 341          *
 342          * @return {boolean} Query exists
 343          */
 344         mw.rcfilters.Controller.prototype.findQueryMatchingCurrentState = function () {
 345                 var highlightedItems = {};
 346
 347                 // Prepare highlights of the current query
 348                 this.filtersModel.getItemsSupportingHighlights().forEach( function ( item ) {
 349                         highlightedItems[ item.getName() ] = item.getHighlightColor();
 350                 } );
 351                 highlightedItems.highlight = this.filtersModel.isHighlightEnabled();
 352
 353                 return this.savedQueriesModel.findMatchingQuery(
 354                         {
 355                                 filters: this.filtersModel.getSelectedState(),
 356                                 highlights: highlightedItems,
 357                                 invert: this.filtersModel.areNamespacesInverted()
 358                         }
 359                 );
 360         };
 361
 362         /**
 363          * Get an object representing the base state of parameters
 364          * and highlights.
 365          *
 366          * This is meant to make sure that the saved queries that are
 367          * in memory are always the same structure as what we would get
 368          * by calling the current model's "getSelectedState" and by checking
 369          * highlight items.
 370          *
 371          * In cases where a user saved a query when the system had a certain
 372          * set of filters, and then a filter was added to the system, we want
 373          * to make sure that the stored queries can still be comparable to
 374          * the current state, which means that we need the base state for
 375          * two operations:
 376          *
 377          * - Saved queries are stored in "minimal" view (only changed filters
 378          *   are stored); When we initialize the system, we merge each minimal
 379          *   query with the base state (using 'getNormalizedFilters') so all
 380          *   saved queries have the exact same structure as what we would get
 381          *   by checking the getSelectedState of the filter.
 382          * - When we save the queries, we minimize the object to only represent
 383          *   whatever has actually changed, rather than store the entire
 384          *   object. To check what actually is different so we can store it,
 385          *   we need to obtain a base state to compare against, this is
 386          *   what #_getMinimalFilterList does
 387          */
 388         mw.rcfilters.Controller.prototype._buildBaseFilterState = function () {
 389                 var defaultParams = this.filtersModel.getDefaultParams(),
 390                         highlightedItems = {};
 391
 392                 // Prepare highlights
 393                 this.filtersModel.getItemsSupportingHighlights().forEach( function ( item ) {
 394                         highlightedItems[ item.getName() ] = null;
 395                 } );
 396                 highlightedItems.highlight = false;
 397
 398                 this.baseFilterState = {
 399                         filters: this.filtersModel.getFiltersFromParameters( defaultParams ),
 400                         highlights: highlightedItems,
 401                         invert: false
 402                 };
 403         };
 404
 405         /**
 406          * Get an object representing the base filter state of both
 407          * filters and highlights. The structure is similar to what we use
 408          * to store each query in the saved queries object:
 409          * {
 410          *    filters: {
 411          *        filterName: (bool)
 412          *    },
 413          *    highlights: {
 414          *        filterName: (string|null)
 415          *    }
 416          * }
 417          *
 418          * @return {Object} Object representing the base state of
 419          *  parameters and highlights
 420          */
 421         mw.rcfilters.Controller.prototype._getBaseFilterState = function () {
 422                 return this.baseFilterState;
 423         };
 424
 425         /**
 426          * Get an object that holds only the parameters and highlights that have
 427          * values different than the base default value.
 428          *
 429          * This is the reverse of the normalization we do initially on loading and
 430          * initializing the saved queries model.
 431          *
 432          * @param {Object} valuesObject Object representing the state of both
 433          *  filters and highlights in its normalized version, to be minimized.
 434          * @return {Object} Minimal filters and highlights list
 435          */
 436         mw.rcfilters.Controller.prototype._getMinimalFilterList = function ( valuesObject ) {
 437                 var result = { filters: {}, highlights: {} },
 438                         baseState = this._getBaseFilterState();
 439
 440                 // XOR results
 441                 $.each( valuesObject.filters, function ( name, value ) {
 442                         if ( baseState.filters !== undefined && baseState.filters[ name ] !== value ) {
 443                                 result.filters[ name ] = value;
 444                         }
 445                 } );
 446
 447                 $.each( valuesObject.highlights, function ( name, value ) {
 448                         if ( baseState.highlights !== undefined && baseState.highlights[ name ] !== value ) {
 449                                 result.highlights[ name ] = value;
 450                         }
 451                 } );
 452
 453                 return result;
 454         };
 455
 456         /**
 457          * Save the current state of the saved queries model with all
 458          * query item representation in the user settings.
 459          */
 460         mw.rcfilters.Controller.prototype._saveSavedQueries = function () {
 461                 var stringified,
 462                         state = this.savedQueriesModel.getState(),
 463                         controller = this;
 464
 465                 // Minimize before save
 466                 $.each( state.queries, function ( queryID, info ) {
 467                         state.queries[ queryID ].data = controller._getMinimalFilterList( info.data );
 468                 } );
 469
 470                 // Stringify state
 471                 stringified = JSON.stringify( state );
 472
 473                 if ( stringified.length > 65535 ) {
 474                         // Sanity check, since the preference can only hold that.
 475                         return;
 476                 }
 477
 478                 // Save the preference
 479                 new mw.Api().saveOption( 'rcfilters-saved-queries', stringified );
 480                 // Update the preference for this session
 481                 mw.user.options.set( 'rcfilters-saved-queries', stringified );
 482         };
 483
 484         /**
 485          * Synchronize the URL with the current state of the filters
 486          * without adding an history entry.
 487          */
 488         mw.rcfilters.Controller.prototype.replaceUrl = function () {
 489                 mw.rcfilters.UriProcessor.static.replaceState( this._getUpdatedUri() );
 490         };
 491
 492         /**
 493          * Update filter state (selection and highlighting) based
 494          * on current URL values.
 495          *
 496          * @param {boolean} [fetchChangesList=true] Fetch new results into the changes
 497          *  list based on the updated model.
 498          */
 499         mw.rcfilters.Controller.prototype.updateStateFromUrl = function ( fetchChangesList ) {
 500                 fetchChangesList = fetchChangesList === undefined ? true : !!fetchChangesList;
 501
 502                 this.uriProcessor.updateModelBasedOnQuery( new mw.Uri().query );
 503
 504                 // Only update and fetch new results if it is requested
 505                 if ( fetchChangesList ) {
 506                         this.updateChangesList();
 507                 }
 508         };
 509
 510         /**
 511          * Update the list of changes and notify the model
 512          *
 513          * @param {Object} [params] Extra parameters to add to the API call
 514          */
 515         mw.rcfilters.Controller.prototype.updateChangesList = function ( params ) {
 516                 this._updateURL( params );
 517                 this.changesListModel.invalidate();
 518                 this._fetchChangesList()
 519                         .then(
 520                                 // Success
 521                                 function ( pieces ) {
 522                                         var $changesListContent = pieces.changes,
 523                                                 $fieldset = pieces.fieldset;
 524                                         this.changesListModel.update( $changesListContent, $fieldset );
 525                                 }.bind( this )
 526                                 // Do nothing for failure
 527                         );
 528         };
 529
 530         /**
 531          * Get an object representing the default parameter state, whether
 532          * it is from the model defaults or from the saved queries.
 533          *
 534          * @return {Object} Default parameters
 535          */
 536         mw.rcfilters.Controller.prototype._getDefaultParams = function () {
 537                 var data, queryHighlights,
 538                         savedParams = {},
 539                         savedHighlights = {},
 540                         defaultSavedQueryItem = this.savedQueriesModel.getItemByID( this.savedQueriesModel.getDefault() );
 541
 542                 if ( mw.config.get( 'wgStructuredChangeFiltersEnableSaving' ) &&
 543                         defaultSavedQueryItem ) {
 544
 545                         data = defaultSavedQueryItem.getData();
 546
 547                         queryHighlights = data.highlights || {};
 548                         savedParams = this.filtersModel.getParametersFromFilters( data.filters || {} );
 549
 550                         // Translate highlights to parameters
 551                         savedHighlights.highlight = String( Number( queryHighlights.highlight ) );
 552                         $.each( queryHighlights, function ( filterName, color ) {
 553                                 if ( filterName !== 'highlights' ) {
 554                                         savedHighlights[ filterName + '_color' ] = color;
 555                                 }
 556                         } );
 557
 558                         return $.extend( true, {}, savedParams, savedHighlights, { invert: data.invert } );
 559                 }
 560
 561                 return $.extend(
 562                         { highlight: '0' },
 563                         this.filtersModel.getDefaultParams()
 564                 );
 565         };
 566
 567         /**
 568          * Get an object representing the default parameter state, whether
 569          * it is from the model defaults or from the saved queries.
 570          *
 571          * @return {Object} Default parameters
 572          */
 573         mw.rcfilters.Controller.prototype._getDefaultParams = function () {
 574                 var data, queryHighlights,
 575                         savedParams = {},
 576                         savedHighlights = {},
 577                         defaultSavedQueryItem = this.savedQueriesModel.getItemByID( this.savedQueriesModel.getDefault() );
 578
 579                 if ( mw.config.get( 'wgStructuredChangeFiltersEnableSaving' ) &&
 580                         defaultSavedQueryItem ) {
 581
 582                         data = defaultSavedQueryItem.getData();
 583
 584                         queryHighlights = data.highlights || {};
 585                         savedParams = this.filtersModel.getParametersFromFilters( data.filters || {} );
 586
 587                         // Translate highlights to parameters
 588                         savedHighlights.highlight = String( Number( queryHighlights.highlight ) );
 589                         $.each( queryHighlights, function ( filterName, color ) {
 590                                 if ( filterName !== 'highlights' ) {
 591                                         savedHighlights[ filterName + '_color' ] = color;
 592                                 }
 593                         } );
 594
 595                         return $.extend( true, {}, savedParams, savedHighlights );
 596                 }
 597
 598                 return this.filtersModel.getDefaultParams();
 599         };
 600
 601         /**
 602          * Update the URL of the page to reflect current filters
 603          *
 604          * This should not be called directly from outside the controller.
 605          * If an action requires changing the URL, it should either use the
 606          * highlighting actions below, or call #updateChangesList which does
 607          * the uri corrections already.
 608          *
 609          * @param {Object} [params] Extra parameters to add to the API call
 610          */
 611         mw.rcfilters.Controller.prototype._updateURL = function ( params ) {
 612                 var currentUri = new mw.Uri(),
 613                         updatedUri = this._getUpdatedUri();
 614
 615                 updatedUri.extend( params || {} );
 616
 617                 if (
 618                         this.uriProcessor.getVersion( currentUri.query ) !== 2 ||
 619                         this.uriProcessor.isNewState( currentUri.query, updatedUri.query )
 620                 ) {
 621                         mw.rcfilters.UriProcessor.static.replaceState( updatedUri );
 622                 }
 623         };
 624
 625         /**
 626          * Get an updated mw.Uri object based on the model state
 627          *
 628          * @return {mw.Uri} Updated Uri
 629          */
 630         mw.rcfilters.Controller.prototype._getUpdatedUri = function () {
 631                 var uri = new mw.Uri();
 632
 633                 // Minimize url
 634                 uri.query = this.uriProcessor.minimizeQuery(
 635                         $.extend(
 636                                 true,
 637                                 {},
 638                                 // We want to retain unrecognized params
 639                                 // The uri params from model will override
 640                                 // any recognized value in the current uri
 641                                 // query, retain unrecognized params, and
 642                                 // the result will then be minimized
 643                                 uri.query,
 644                                 this.uriProcessor.getUriParametersFromModel(),
 645                                 { urlversion: '2' }
 646                         )
 647                 );
 648
 649                 return uri;
 650         };
 651
 652         /**
 653          * Fetch the list of changes from the server for the current filters
 654          *
 655          * @return {jQuery.Promise} Promise object that will resolve with the changes list
 656          *  or with a string denoting no results.
 657          */
 658         mw.rcfilters.Controller.prototype._fetchChangesList = function () {
 659                 var uri = this._getUpdatedUri(),
 660                         requestId = ++this.requestCounter,
 661                         latestRequest = function () {
 662                                 return requestId === this.requestCounter;
 663                         }.bind( this );
 664
 665                 return $.ajax( uri.toString(), { contentType: 'html' } )
 666                         .then(
 667                                 // Success
 668                                 function ( html ) {
 669                                         var $parsed;
 670                                         if ( !latestRequest() ) {
 671                                                 return $.Deferred().reject();
 672                                         }
 673
 674                                         $parsed = $( $.parseHTML( html ) );
 675
 676                                         return {
 677                                                 // Changes list
 678                                                 changes: $parsed.find( '.mw-changeslist' ).first().contents(),
 679                                                 // Fieldset
 680                                                 fieldset: $parsed.find( 'fieldset.rcoptions' ).first()
 681                                         };
 682                                 },
 683                                 // Failure
 684                                 function ( responseObj ) {
 685                                         var $parsed;
 686
 687                                         if ( !latestRequest() ) {
 688                                                 return $.Deferred().reject();
 689                                         }
 690
 691                                         $parsed = $( $.parseHTML( responseObj.responseText ) );
 692
 693                                         // Force a resolve state to this promise
 694                                         return $.Deferred().resolve( {
 695                                                 changes: 'NO_RESULTS',
 696                                                 fieldset: $parsed.find( 'fieldset.rcoptions' ).first()
 697                                         } ).promise();
 698                                 }
 699                         );
 700         };
 701
 702         /**
 703          * Track usage of highlight feature
 704          *
 705          * @param {string} action
 706          * @param {array|object|string} filters
 707          */
 708         mw.rcfilters.Controller.prototype._trackHighlight = function ( action, filters ) {
 709                 filters = typeof filters === 'string' ? { name: filters } : filters;
 710                 filters = !Array.isArray( filters ) ? [ filters ] : filters;
 711                 mw.track(
 712                         'event.ChangesListHighlights',
 713                         {
 714                                 action: action,
 715                                 filters: filters,
 716                                 userId: mw.user.getId()
 717                         }
 718                 );
 719         };
 720
 721 }( mediaWiki, jQuery ) );