AsPageableMixin to make backbone.pageable to stay on same page during fetch

Closes #670

src/UI/Activity/Queue/QueueCollection.js

@@ -1,8 +1,10 @@
 var _ = require('underscore');
 var PageableCollection = require('backbone.pageable');
+//var PageableCollection = require('../../Shared/Grid/SonarrPageableCollection');
 var QueueModel = require('./QueueModel');
 var FormatHelpers = require('../../Shared/FormatHelpers');
 var AsSortedCollection = require('../../Mixins/AsSortedCollection');
+var AsPageableCollection = require('../../Mixins/AsPageableCollection');
 var moment = require('moment');
 
 require('../../Mixins/backbone.signalr.mixin');
@@ -64,9 +66,9 @@ var QueueCollection = PageableCollection.extend({
 });
 
 QueueCollection = AsSortedCollection.call(QueueCollection);
+QueueCollection = AsPageableCollection.call(QueueCollection);
 
 var collection = new QueueCollection().bindSignalR();
 collection.fetch();
 
-
 module.exports = collection;

src/UI/Mixins/AsPageableCollection.js

@@ -0,0 +1,45 @@
+var _ = require('underscore');
+
+module.exports = function() {
+    var originalMakeCollectionEventHandler = this.prototype._makeCollectionEventHandler;
+
+    this.prototype._makeCollectionEventHandler = function (pageCollection, fullCollection) {
+        var self = this;
+        this.pageCollection = pageCollection;
+        this.fullCollection = fullCollection;
+        var eventHandler = originalMakeCollectionEventHandler.apply(this, arguments);
+
+        return _.wrap(eventHandler, _.bind(self._resetEventHandler, self));
+    };
+
+    this.prototype._resetEventHandler = function (originalEventHandler, event, model, collection, options) {
+        if (event === 'reset') {
+            var currentPage = this.state.currentPage;
+            var pageSize = this.state.pageSize;
+
+            originalEventHandler.apply(this, [].slice.call(arguments, 1));
+
+            var totalPages = Math.ceil(this.state.totalRecords / pageSize);
+            var newPage = Math.min(currentPage, totalPages);
+
+            if (newPage !== this.state.currentPage) {
+                this.state.currentPage = newPage;
+
+                // If backbone pageable fixes their reset bug
+                // (they reset the page number, but not the range),
+                // we'll want to do this for all resets where the page number changed
+                if (currentPage !== newPage) {
+                    var pageStart = (newPage - 1) * pageSize;
+                    var pageEnd = pageStart + pageSize;
+
+                    this.pageCollection.reset(this.fullCollection.models.slice(pageStart, pageEnd),
+                        _.extend({}, options, { parse : false }));
+                }
+            }
+        } else {
+            originalEventHandler.call(this, [].slice.call(arguments, 1));
+        }
+    };
+
+    return this;
+};