resources/src/mediawiki.widgets/mw.widgets.CategoryCapsuleItemWidget.js

   1 /*!
   2  * MediaWiki Widgets - CategoryCapsuleItemWidget class.
   3  *
   4  * @copyright 2011-2015 MediaWiki Widgets Team and others; see AUTHORS.txt
   5  * @license The MIT License (MIT); see LICENSE.txt
   6  */
   7 ( function ( $, mw ) {
   8
   9         /**
  10          * @class mw.widgets.CategoryCapsuleItemWidget
  11          */
  12
  13         var processExistenceCheckQueueDebounced,
  14                 api = new mw.Api(),
  15                 currentRequest = null,
  16                 existenceCache = {},
  17                 existenceCheckQueue = {};
  18
  19         // The existence checking code really could be refactored into a separate class.
  20
  21         /**
  22          * @private
  23          */
  24         function processExistenceCheckQueue() {
  25                 var queue, titles;
  26                 if ( currentRequest ) {
  27                         // Don't fire off a million requests at the same time
  28                         currentRequest.always( function () {
  29                                 currentRequest = null;
  30                                 processExistenceCheckQueueDebounced();
  31                         } );
  32                         return;
  33                 }
  34                 queue = existenceCheckQueue;
  35                 existenceCheckQueue = {};
  36                 titles = Object.keys( queue ).filter( function ( title ) {
  37                         if ( existenceCache.hasOwnProperty( title ) ) {
  38                                 queue[ title ].resolve( existenceCache[ title ] );
  39                         }
  40                         return !existenceCache.hasOwnProperty( title );
  41                 } );
  42                 if ( !titles.length ) {
  43                         return;
  44                 }
  45                 currentRequest = api.get( {
  46                         action: 'query',
  47                         prop: [ 'info' ],
  48                         titles: titles
  49                 } ).done( function ( response ) {
  50                         var index, curr, title;
  51                         for ( index in response.query.pages ) {
  52                                 curr = response.query.pages[ index ];
  53                                 title = mw.Title.newFromText( curr.title ).getPrefixedText();
  54                                 existenceCache[ title ] = curr.missing === undefined;
  55                                 queue[ title ].resolve( existenceCache[ title ] );
  56                         }
  57                 } );
  58         }
  59
  60         processExistenceCheckQueueDebounced = OO.ui.debounce( processExistenceCheckQueue );
  61
  62         /**
  63          * Register a request to check whether a page exists.
  64          *
  65          * @private
  66          * @param {mw.Title} title
  67          * @return {jQuery.Promise} Promise resolved with true if the page exists or false otherwise
  68          */
  69         function checkPageExistence( title ) {
  70                 var key = title.getPrefixedText();
  71                 if ( !existenceCheckQueue[ key ] ) {
  72                         existenceCheckQueue[ key ] = $.Deferred();
  73                 }
  74                 processExistenceCheckQueueDebounced();
  75                 return existenceCheckQueue[ key ].promise();
  76         }
  77
  78         /**
  79          * Category selector capsule item widget. Extends OO.ui.CapsuleItemWidget with the ability to link
  80          * to the given page, and to show its existence status (i.e., whether it is a redlink).
  81          *
  82          * @uses mw.Api
  83          * @extends OO.ui.CapsuleItemWidget
  84          *
  85          * @constructor
  86          * @param {Object} config Configuration options
  87          * @cfg {mw.Title} title Page title to use (required)
  88          */
  89         mw.widgets.CategoryCapsuleItemWidget = function MWWCategoryCapsuleItemWidget( config ) {
  90                 // Parent constructor
  91                 mw.widgets.CategoryCapsuleItemWidget.parent.call( this, $.extend( {
  92                         data: config.title.getMainText(),
  93                         label: config.title.getMainText()
  94                 }, config ) );
  95
  96                 // Properties
  97                 this.title = config.title;
  98                 this.$link = $( '<a>' )
  99                         .text( this.label )
 100                         .attr( 'target', '_blank' )
 101                         .on( 'click', function ( e ) {
 102                                 // CapsuleMultiSelectWidget really wants to prevent you from clicking the link, don't let it
 103                                 e.stopPropagation();
 104                         } );
 105
 106                 // Initialize
 107                 this.setMissing( false );
 108                 this.$label.replaceWith( this.$link );
 109                 this.setLabelElement( this.$link );
 110                 checkPageExistence( this.title ).done( function ( exists ) {
 111                         this.setMissing( !exists );
 112                 }.bind( this ) );
 113         };
 114
 115         /* Setup */
 116
 117         OO.inheritClass( mw.widgets.CategoryCapsuleItemWidget, OO.ui.CapsuleItemWidget );
 118
 119         /* Methods */
 120
 121         /**
 122          * Update label link href and CSS classes to reflect page existence status.
 123          *
 124          * @private
 125          * @param {boolean} missing Whether the page is missing (does not exist)
 126          */
 127         mw.widgets.CategoryCapsuleItemWidget.prototype.setMissing = function ( missing ) {
 128                 if ( !missing ) {
 129                         this.$link
 130                                 .attr( 'href', this.title.getUrl() )
 131                                 .removeClass( 'new' );
 132                 } else {
 133                         this.$link
 134                                 .attr( 'href', this.title.getUrl( { action: 'edit', redlink: 1 } ) )
 135                                 .addClass( 'new' );
 136                 }
 137         };
 138
 139 }( jQuery, mediaWiki ) );