diff --git a/app/models/topic.rb b/app/models/topic.rb
index 9563ddc2e..e2b6bb441 100644
--- a/app/models/topic.rb
+++ b/app/models/topic.rb
@@ -560,60 +560,8 @@ class Topic < ActiveRecord::Base
save
end
- # Create the summary of the interesting posters in a topic. Cheats to avoid
- # many queries.
- def posters_summary(topic_user = nil, current_user = nil, opts={})
- return @posters_summary if @posters_summary.present?
- descriptions = {}
-
- # Use an avatar lookup object if we have it, otherwise create one just for this forum topic
- al = opts[:avatar_lookup]
- if al.blank?
- al = AvatarLookup.new([user_id, last_post_user_id, featured_user1_id, featured_user2_id, featured_user3_id])
- end
-
- # Helps us add a description to a poster
- add_description = lambda do |u, desc|
- if u.present?
- descriptions[u.id] ||= []
- descriptions[u.id] << I18n.t(desc)
- end
- end
-
- add_description.call(al[user_id], :original_poster)
- add_description.call(al[featured_user1_id], :most_posts)
- add_description.call(al[featured_user2_id], :frequent_poster)
- add_description.call(al[featured_user3_id], :frequent_poster)
- add_description.call(al[featured_user4_id], :frequent_poster)
- add_description.call(al[last_post_user_id], :most_recent_poster)
-
-
- @posters_summary = [al[user_id],
- al[last_post_user_id],
- al[featured_user1_id],
- al[featured_user2_id],
- al[featured_user3_id],
- al[featured_user4_id]
- ].compact.uniq[0..4]
-
- unless @posters_summary[0] == al[last_post_user_id]
- # shuffle last_poster to back
- @posters_summary.reject!{|u| u == al[last_post_user_id]}
- @posters_summary << al[last_post_user_id]
- end
- @posters_summary.map! do |p|
- if p
- result = TopicPoster.new
- result.user = p
- result.description = descriptions[p.id].join(', ')
- result.extras = "latest" if al[last_post_user_id] == p
- result
- else
- nil
- end
- end.compact!
-
- @posters_summary
+ def posters_summary(options = {})
+ @posters_summary ||= TopicPostersSummary.new(self, options).summary
end
# Enable/disable the star on the topic
diff --git a/app/models/topic_posters_summary.rb b/app/models/topic_posters_summary.rb
new file mode 100644
index 000000000..b3c0e42ae
--- /dev/null
+++ b/app/models/topic_posters_summary.rb
@@ -0,0 +1,79 @@
+class TopicPostersSummary
+ attr_reader :topic, :options
+
+ def initialize(topic, options = {})
+ @topic = topic
+ @options = options
+ end
+
+ def summary
+ sorted_top_posters.map { |user| new_topic_poster_for user }
+ end
+
+ private
+
+ def new_topic_poster_for(user)
+ TopicPoster.new.tap do |topic_poster|
+ topic_poster.user = user
+ topic_poster.description = descriptions_for(user)
+ topic_poster.extras = 'latest' if is_latest_poster?(user)
+ end
+ end
+
+ def descriptions_by_id
+ @descriptions_by_id ||= begin
+ user_ids_with_descriptions.inject({}) do |descriptions, (id, description)|
+ descriptions[id] ||= []
+ descriptions[id] << description
+ descriptions
+ end
+ end
+ end
+
+ def descriptions_for(user)
+ descriptions_by_id[user.id].join ', '
+ end
+
+ def shuffle_last_poster_to_back_in(summary)
+ unless last_poster_is_topic_creator?
+ summary.reject!{ |u| u.id == topic.last_post_user_id }
+ summary << avatar_lookup[topic.last_post_user_id]
+ end
+ summary
+ end
+
+ def user_ids_with_descriptions
+ user_ids.zip([
+ :original_poster,
+ :most_recent_poster,
+ :most_posts,
+ :frequent_poster,
+ :frequent_poster,
+ :frequent_poster
+ ].map { |description| I18n.t(description) })
+ end
+
+ def last_poster_is_topic_creator?
+ topic.user_id == topic.last_post_user_id
+ end
+
+ def is_latest_poster?(user)
+ topic.last_post_user_id == user.id
+ end
+
+ def sorted_top_posters
+ shuffle_last_poster_to_back_in top_posters
+ end
+
+ def top_posters
+ user_ids.map { |id| avatar_lookup[id] }.compact.uniq.take(5)
+ end
+
+ def user_ids
+ [ topic.user_id, topic.last_post_user_id, *topic.featured_user_ids ]
+ end
+
+ def avatar_lookup
+ @avatar_lookup ||= options[:avatar_lookup] || AvatarLookup.new(user_ids)
+ end
+end
diff --git a/spec/models/topic_posters_summary_spec.rb b/spec/models/topic_posters_summary_spec.rb
new file mode 100644
index 000000000..06d02f9db
--- /dev/null
+++ b/spec/models/topic_posters_summary_spec.rb
@@ -0,0 +1,71 @@
+require 'spec_helper'
+
+describe TopicPostersSummary do
+ describe '#summary' do
+ let(:summary) { described_class.new(topic).summary }
+
+ let(:topic) do
+ Fabricate(:topic,
+ user: topic_creator,
+ last_poster: last_poster,
+ featured_user1: featured_user1,
+ featured_user2: featured_user2,
+ featured_user3: featured_user3,
+ featured_user4: featured_user4
+ )
+ end
+
+ let(:topic_creator) { Fabricate(:user) }
+ let(:last_poster) { nil }
+ let(:featured_user1) { nil }
+ let(:featured_user2) { nil }
+ let(:featured_user3) { nil }
+ let(:featured_user4) { nil }
+
+ it 'contains only the topic creator when there are no other posters' do
+ expect(summary.count).to eq 1
+
+ summary.first.tap do |topic_poster|
+ expect(topic_poster.user).to eq topic_creator
+ expect(topic_poster.extras).to eq 'latest'
+ expect(topic_poster.description).to eq(
+ "#{I18n.t(:original_poster)}, #{I18n.t(:most_recent_poster)}"
+ )
+ end
+ end
+
+ context 'when the lastest poster is also the topic creator' do
+ let(:last_poster) { topic_creator }
+ let(:featured_user1) { Fabricate(:user) }
+
+ before do
+ topic.last_poster = topic_creator
+ topic.featured_user1 = featured_user1
+ topic.save!
+ end
+
+ it 'keeps the topic creator at the front of the summary' do
+ expect(summary.map(&:user)).to eq([
+ topic_creator,
+ featured_user1
+ ])
+ end
+ end
+
+ context 'when the topic has many posters' do
+ let(:last_poster) { Fabricate(:user) }
+ let(:featured_user1) { Fabricate(:user) }
+ let(:featured_user2) { Fabricate(:user) }
+ let(:featured_user3) { Fabricate(:user) }
+ let(:featured_user4) { Fabricate(:user) }
+
+ it 'contains only five posters with latest poster at the end' do
+ expect(summary.map(&:user)).to eq([
+ topic_creator,
+ featured_user1, featured_user2, featured_user3,
+ last_poster
+ ])
+ end
+ end
+ end
+end