User tracking state implementation progress for live unread / new counts

app/models/user_tracking_state.rb

@@ -7,6 +7,8 @@ class UserTrackingState
 
   CHANNEL = "/user-tracking"
 
+  attr_accessor :user_id, :topic_id, :highest_post_number, :last_read_post_number, :created_at
+
   MessageBus.client_filter(CHANNEL) do |user_id, message|
     if user_id
       UserTrackingState.new(User.find(user_id)).filter(message)
@@ -19,23 +21,61 @@ class UserTrackingState
     MessageBus.publish(CHANNEL, "CHANGE", user_ids: [user_id].compact)
   end
 
-  def initialize(user)
-    @user = user
-    @query = TopicQuery.new(@user)
+  def self.treat_as_new_topic_clause
+    User.where("CASE
+                  WHEN COALESCE(u.new_topic_duration_minutes, :default_duration) = :always THEN u.created_at
+                  WHEN COALESCE(u.new_topic_duration_minutes, :default_duration) = :last_visit THEN COALESCE(u.previous_visit_at,u.created_at)
+                  ELSE (:now::timestamp - INTERVAL '1 MINUTE' * COALESCE(u.new_topic_duration_minutes, :default_duration))
+               END",
+                now: DateTime.now,
+                last_visit: User::NewTopicDuration::LAST_VISIT,
+                always: User::NewTopicDuration::ALWAYS,
+                default_duration: SiteSetting.new_topic_duration_minutes
+              ).where_values[0]
   end
 
-  def new_list
-    @query
-      .new_results(limit: false)
-      .select(topics: [:id, :created_at])
-      .map{|t| [t.id, t.created_at]}
-  end
+  def self.report(user_ids, topic_id = nil)
 
-  def unread_list
-    []
-  end
+    # Sam: this is a hairy report, in particular I need custom joins and fancy conditions
+    #  Dropping to sql_builder so I can make sense of it.
+    #
+    # Keep in mind, we need to be able to filter on a GROUP of users, and zero in on topic
+    #  all our existing scope work does not do this
+    #
+    # This code needs to be VERY efficient as it is triggered via the message bus and may steal
+    #  cycles from usual requests
+    #
+
+    unread = TopicQuery.unread_filter(Topic).where_values.join(" AND ")
+    new = TopicQuery.new_filter(Topic, "xxx").where_values.join(" AND ").gsub!("'xxx'", treat_as_new_topic_clause)
+
+    sql = <<SQL
+    SELECT u.id AS user_id, topics.id AS topic_id, topics.created_at, highest_post_number, last_read_post_number
+    FROM users u
+    FULL OUTER JOIN topics ON 1=1
+    LEFT JOIN topic_users tu ON tu.topic_id = topics.id AND tu.user_id = u.id
+    LEFT JOIN categories c ON c.id = topics.id
+    WHERE u.id IN (:user_ids) AND
+          topics.archetype <> 'private_message' AND
+          ((#{unread}) OR (#{new})) AND
+          (topics.visible OR u.admin OR u.moderator) AND
+          topics.deleted_at IS NULL AND
+          ( category_id IS NULL OR NOT c.secure OR category_id IN (
+              SELECT c2.id FROM categories c2
+              JOIN category_groups cg ON cg.category_id = c2.id
+              JOIN group_users gu ON gu.user_id = u.id AND cg.group_id = gu.group_id
+              WHERE c2.secure )
+          )
+
+SQL
+
+    if topic_id
+      sql << " AND topics.id = :topic_id"
+    end
+
+    SqlBuilder.new(sql)
+      .map_exec(UserTrackingState, user_ids: user_ids, topic_id: topic_id)
 
-  def filter(message)
   end
 
 end