make Comment#ordered_for_story_or_thread_for_user work on query scope

app/controllers/comments_controller.rb

@@ -232,7 +232,13 @@ class CommentsController < ApplicationController
     end
 
     @threads = @showing_user.recent_threads(20).map{|r|
-      cs = Comment.ordered_for_story_or_thread_for_user(nil, r, @showing_user)
+      cs = Comment.where(
+        :thread_id => r
+      ).includes(
+        :user, :story
+      ).arrange_for_user(
+        @showing_user
+      )
 
       if @user && (@showing_user.id == @user.id)
         @votes = Vote.comment_votes_by_user_for_story_hash(@user.id,

app/controllers/stories_controller.rb

@@ -126,8 +126,7 @@ class StoriesController < ApplicationController
 
     @short_url = @story.short_id_url
 
-    @comments = Comment.ordered_for_story_or_thread_for_user(@story.id, nil,
-      @user)
+    @comments = @story.comments.includes(:user).arrange_for_user(@user)
 
     respond_to do |format|
       format.html {
@@ -155,8 +154,11 @@ class StoriesController < ApplicationController
       return redirect_to @story.comments_url
     end
 
-    @comments = Comment.ordered_for_story_or_thread_for_user(@story.id,
-      @showing_comment.thread_id, @user ? @user : nil)
+    @comments = @story.comments
+    if @showing_comment.thread_id
+      @comments = @comments.where(:thread_id => @showing_comment.thread_id)
+    end
+    @comments = @comments.includes(:user).arrange_for_user(@user)
 
     @comments.each do |c,x|
       if c.id == @showing_comment.id

app/models/comment.rb

@@ -1,6 +1,7 @@
 class Comment < ActiveRecord::Base
   belongs_to :user
-  belongs_to :story
+  belongs_to :story,
+    :inverse_of => :comments
   has_many :votes,
     :dependent => :delete_all
   belongs_to :parent_comment,
@@ -293,16 +294,10 @@ class Comment < ActiveRecord::Base
     comment
   end
 
-  def self.ordered_for_story_or_thread_for_user(story_id, thread_id, user)
+  def self.arrange_for_user(user)
     parents = {}
 
-    if thread_id
-      cs = [ "thread_id = ?", thread_id ]
-    else
-      cs = [ "story_id = ?", story_id ]
-    end
-
-    Comment.where(*cs).order("confidence DESC").includes(:user).each do |c|
+    self.order("confidence DESC").each do |c|
       (parents[c.parent_comment_id.to_i] ||= []).push c
     end
 

app/models/story.rb

@@ -2,7 +2,8 @@ class Story < ActiveRecord::Base
   belongs_to :user
   has_many :taggings,
     :autosave => true
-  has_many :comments
+  has_many :comments,
+    :inverse_of => :story
   has_many :tags, :through => :taggings
 
   validates_length_of :title, :in => 3..150
@@ -381,9 +382,9 @@ class Story < ActiveRecord::Base
   end
 
   def update_comments_count!
+    comments = self.comments.arrange_for_user(nil)
+
     # calculate count after removing deleted comments and threads
-    self.update_column :comments_count,
-      Comment.ordered_for_story_or_thread_for_user(self.id, nil, nil).select{|c|
-      !c.is_gone? }.count
+    self.update_column :comments_count, comments.count{|c| !c.is_gone? }
   end
 end

script/mail_new_activity

@@ -153,7 +153,7 @@ last_comment_id, false, false).order(:id).each do |c|
 
         thread = []
         indent_level = 0
-        Comment.ordered_for_story_or_thread_for_user(nil, c.thread_id,
+        Comment.where(:thread_id => c.thread_id).arrange_for_user(
         nil).reverse.each do |cc|
           if indent_level > 0 && cc.indent_level < indent_level
             thread.unshift cc