Sorting

lms/static/coffee/src/discussion/discussion.coffee

@@ -6,6 +6,7 @@ if Backbone?
       DiscussionUtil.addDiscussion @id, @
       @bind "add", (item) =>
         item.discussion = @
+      @comparator = @sortByDate
 
     find: (id) ->
       _.first @where(id: id)
@@ -16,6 +17,19 @@ if Backbone?
       @add model
       model
 
+    sortByDate: (thread) ->
+      thread.get("created_at")
+
+    sortByVotes: (thread1, thread2) ->
+      thread1_count = parseInt(thread1.get("votes")['up_count'])
+      thread2_count = parseInt(thread2.get("votes")['up_count'])
+      thread2_count - thread1_count
+
+    sortByComments: (thread1, thread2) ->
+      thread1_count = parseInt(thread1.get("comments_count"))
+      thread2_count = parseInt(thread2.get("comments_count"))
+      thread2_count - thread1_count
+
   class @DiscussionView extends Backbone.View
 
     $: (selector) ->

lms/static/coffee/src/discussion/discussion_router.coffee

@@ -8,7 +8,6 @@ class @DiscussionRouter extends Backbone.Router
       @nav = new DiscussionThreadListView(collection: @discussion, el: $(".sidebar"))
       @nav.on "thread:selected", @navigateToThread
       @nav.render()
-      @main = new DiscussionThreadView(el: $(".discussion-column"))
 
   allThreads: ->
       true
@@ -16,7 +15,10 @@ class @DiscussionRouter extends Backbone.Router
   showThread: (forum_name, thread_id) ->
     @nav.setActiveThread(thread_id)
     thread = @discussion.get(thread_id)
-    @main.model = thread
+    if(@main)
+      @main.undelegateEvents()
+
+    @main = new DiscussionThreadView(el: $(".discussion-column"), model: thread)
     @main.render()
 
   navigateToThread: (thread_id) =>

lms/static/coffee/src/discussion/views/discussion_thread_list_view.coffee

@@ -3,6 +3,7 @@ class @DiscussionThreadListView extends Backbone.View
   events:
     "click .search": "showSearch"
     "keyup .post-search-field": "performSearch"
+    "click .sort-bar a": "sortThreads"
 
   render: ->
     @timer = 0;
@@ -26,7 +27,7 @@ class @DiscussionThreadListView extends Backbone.View
     @trigger("thread:selected", thread_id)
 
   setActiveThread: (thread_id) ->
-    @$("a").removeClass("active")
+    @$(".post-list a").removeClass("active")
     @$("a[data-id='#{thread_id}']").addClass("active")
 
   showSearch: ->
@@ -34,6 +35,20 @@ class @DiscussionThreadListView extends Backbone.View
     @$(".browse").removeClass('is-open');
     setTimeout (-> @$(".post-search-field").focus()), 200
 
+  sortThreads: (event) ->
+    @$(".sort-bar a").removeClass("active")
+    $(event.target).addClass("active")
+    sortBy = $(event.target).data("sort")
+    if sortBy == "date"
+      @collection.comparator = @collection.sortByDate
+    else if sortBy == "votes"
+      @collection.comparator = @collection.sortByVotes
+    else if sortBy == "comments"
+      @collection.comparator = @collection.sortByComments
+    @collection.sort()
+
+
+
   delay: (callback, ms) =>
     clearTimeout(@timer)
     @timer = setTimeout(callback, ms)

lms/templates/discussion/single_thread.html

@@ -18,12 +18,17 @@
     $$contents = {};
     $$discussions = {};
     $$course_id = "${course_id}";
-    $(document).ready(function() {
+    DiscussionApp = {
+      start: function() {
         window.user = new DiscussionUser(JSON.parse("${user_info | escapejs}"));
         var discussion = new Discussion(JSON.parse("${threads | escapejs}"));
 
         new DiscussionRouter({discussion: discussion});
         Backbone.history.start({pushState: true, root: "/courses/${course_id}/discussion/forum/"});
+       }
+    }
+    $(document).ready(function() {
+        DiscussionApp.start();
     });
 </script>
 </%block>