From 9c8e50351d07776eba5549fbfcb59e568562a348 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?R=C3=A9gis=20Hanol?= <regis@hanol.fr>
Date: Fri, 27 Dec 2013 18:10:35 +0100
Subject: [PATCH] first stab at calculating the score of a topic for the top
 tab

---
 app/controllers/list_controller.rb            |  7 +++----
 app/models/top_topic.rb                       | 19 +++++++++++++++++--
 ...20131227164338_add_scores_to_top_topics.rb |  7 +++++++
 lib/topic_query.rb                            |  7 +++----
 4 files changed, 30 insertions(+), 10 deletions(-)
 create mode 100644 db/migrate/20131227164338_add_scores_to_top_topics.rb

diff --git a/app/controllers/list_controller.rb b/app/controllers/list_controller.rb
index 475322ce47e..e19fdefbc61 100644
--- a/app/controllers/list_controller.rb
+++ b/app/controllers/list_controller.rb
@@ -73,8 +73,7 @@ class ListController < ApplicationController
   end
 
   def top
-    sort_order = params[:sort_order] || "posts"
-    top = generate_top_lists_by(sort_order)
+    top = generate_top_lists
 
     respond_to do |format|
       format.html do
@@ -179,7 +178,7 @@ class ListController < ApplicationController
     public_send(method, opts.merge(next_page_params(opts)))
   end
 
-  def generate_top_lists_by(sort_order)
+  def generate_top_lists
     top = {}
     topic_ids = Set.new
 
@@ -188,7 +187,7 @@ class ListController < ApplicationController
         per_page: SiteSetting.topics_per_period_in_summary,
         except_topic_ids: topic_ids.to_a
       }
-      list = TopicQuery.new(current_user, options).list_top(sort_order, period)
+      list = TopicQuery.new(current_user, options).list_top_for(period)
       topic_ids.merge(list.topic_ids)
       top[period] = list
     end
diff --git a/app/models/top_topic.rb b/app/models/top_topic.rb
index e00ebeccb64..9a30df02297 100644
--- a/app/models/top_topic.rb
+++ b/app/models/top_topic.rb
@@ -20,12 +20,17 @@ class TopTopic < ActiveRecord::Base
                 FROM topics
                 WHERE deleted_at IS NULL
                 AND visible
-                AND NOT archived")
-      # update all the counter caches
+                AND archetype <> :private_message
+                AND NOT archived",
+                private_message: Archetype::private_message)
+
       TopTopic.periods.each do |period|
+        # update all the counter caches
         TopTopic.sort_orders.each do |sort|
           TopTopic.send("update_#{sort}_count_for", period)
         end
+        # compute top score
+        TopTopic.compute_top_score_for(period)
       end
     end
   end
@@ -61,6 +66,16 @@ class TopTopic < ActiveRecord::Base
     TopTopic.update_top_topics(period, "likes", sql)
   end
 
+  def self.compute_top_score_for(period)
+    exec_sql("UPDATE top_topics
+              SET #{period}_score = log(
+                1 +
+                (#{period}_posts_count) *
+                (#{period}_likes_count / 2.0 + 1.0) *
+                (#{period}_views_count / 100.0 + 1.0)
+              )")
+  end
+
   def self.start_of(period)
     case period
       when :yearly  then 1.year.ago
diff --git a/db/migrate/20131227164338_add_scores_to_top_topics.rb b/db/migrate/20131227164338_add_scores_to_top_topics.rb
new file mode 100644
index 00000000000..e8acad62b30
--- /dev/null
+++ b/db/migrate/20131227164338_add_scores_to_top_topics.rb
@@ -0,0 +1,7 @@
+class AddScoresToTopTopics < ActiveRecord::Migration
+  def change
+    TopTopic.periods.each do |period|
+      add_column :top_topics, "#{period}_score".to_sym, :float
+    end
+  end
+end
diff --git a/lib/topic_query.rb b/lib/topic_query.rb
index a8c199dd147..b7064cf1d19 100644
--- a/lib/topic_query.rb
+++ b/lib/topic_query.rb
@@ -84,12 +84,11 @@ class TopicQuery
     create_list(:posted) {|l| l.where('tu.user_id IS NOT NULL') }
   end
 
-  def list_top(sort_order, period)
-    count = "#{period}_#{sort_order}_count"
+  def list_top_for(period)
+    score = "#{period}_score"
     create_list(:top, unordered: true) do |topics|
       topics.joins(:top_topic)
-            .where("top_topics.#{count} > 0")
-            .order("top_topics.#{count} DESC, topics.bumped_at DESC")
+            .order("top_topics.#{score} DESC, topics.bumped_at DESC")
     end
   end