add Likes Recieved to possible stats in summary email

app/mailers/user_notifications.rb

@@ -112,6 +112,11 @@ class UserNotifications < ActionMailer::Base
     value = user.unread_private_messages
     @counts << {label_key: 'user_notifications.digest.unread_messages', value: value, href: "#{Discourse.base_url}/my/messages"} if value > 0
 
+    if @counts.size < 3
+      value = user.unread_notifications_of_type(Notification.types[:liked])
+      @counts << {label_key: 'user_notifications.digest.liked_received', value: value, href: "#{Discourse.base_url}/my/notifications"} if value > 0
+    end
+
     if @counts.size < 3
       @counts << {
         label_key: 'user_notifications.digest.new_posts',

app/models/user.rb

@@ -293,23 +293,22 @@ class User < ActiveRecord::Base
     super
   end
 
-  def unread_private_messages
+  def unread_notifications_of_type(notification_type)
-    @unread_pms ||=
+    # perf critical, much more efficient than AR
-      begin
+    sql = "
-        # perf critical, much more efficient than AR
+       SELECT COUNT(*) FROM notifications n
-        sql = "
+       LEFT JOIN topics t ON n.topic_id = t.id
-           SELECT COUNT(*) FROM notifications n
+       WHERE
-           LEFT JOIN topics t ON n.topic_id = t.id
+        t.deleted_at IS NULL AND
-           WHERE
+        n.notification_type = :type AND
-            t.deleted_at IS NULL AND
+        n.user_id = :user_id AND
-            n.notification_type = :type AND
+        NOT read"
-            n.user_id = :user_id AND
-            NOT read"
 
-        User.exec_sql(sql, user_id: id,
+    User.exec_sql(sql, user_id: id, type: notification_type).getvalue(0,0).to_i
-                           type:  Notification.types[:private_message])
+  end
-            .getvalue(0,0).to_i
+
-      end
+  def unread_private_messages
+    @unread_pms ||= unread_notifications_of_type(Notification.types[:private_message])
   end
 
   def unread_notifications

config/locales/server.en.yml

@@ -2448,6 +2448,7 @@ en:
       new_topics: "New Topics"
       unread_messages: "Unread Messages"
       unread_notifications: "Unread Notifications"
+      liked_received: "Likes Received"
       new_posts: "New Posts"
       new_users: "New Users"
       popular_topics: "Popular Topics"