Chore: Refactor round robin logic (#1015)

Co-authored-by: Pranav Raj S <pranav@thoughtwoot.com>

spec/models/conversation_spec.rb

@@ -108,6 +108,7 @@ RSpec.describe Conversation, type: :model do
     end
 
     before do
+      create(:inbox_member, inbox: inbox, user: agent)
       allow(Redis::Alfred).to receive(:rpoplpush).and_return(agent.id)
     end
 
@@ -141,9 +142,11 @@ RSpec.describe Conversation, type: :model do
       conversation.status = 'resolved'
       conversation.save!
       expect(conversation.reload.assignee).to eq(agent)
+      inbox.inbox_members.where(user_id: agent.id).first.destroy!
 
       # round robin changes assignee in this case since agent doesn't have access to inbox
       agent2 = create(:user, email: 'agent2@example.com', account: account)
+      create(:inbox_member, inbox: inbox, user: agent2)
       allow(Redis::Alfred).to receive(:rpoplpush).and_return(agent2.id)
       conversation.status = 'open'
       conversation.save!

spec/services/round_robin/manage_service_spec.rb

@@ -0,0 +1,41 @@
+require 'rails_helper'
+
+describe RoundRobin::ManageService do
+  let!(:account) { create(:account) }
+  let!(:inbox) { create(:inbox, account: account) }
+  let!(:inbox_members) { create_list(:inbox_member, 5, inbox: inbox) }
+  let(:subject) { ::RoundRobin::ManageService.new(inbox: inbox) }
+
+  describe '#available_agent' do
+    it 'gets the first available agent and move agent to end of the list' do
+      expected_queue = [inbox_members[0].user_id, inbox_members[4].user_id, inbox_members[3].user_id, inbox_members[2].user_id,
+                        inbox_members[1].user_id].map(&:to_s)
+      subject.available_agent
+      expect(subject.send(:queue)).to eq(expected_queue)
+    end
+
+    it 'gets intersection of priority list and agent queue. get and move agent to the end of the list' do
+      expected_queue = [inbox_members[2].user_id, inbox_members[4].user_id, inbox_members[3].user_id, inbox_members[1].user_id,
+                        inbox_members[0].user_id].map(&:to_s)
+      expect(subject.available_agent(priority_list: [inbox_members[3].user_id, inbox_members[2].user_id])).to eq inbox_members[2].user
+      expect(subject.send(:queue)).to eq(expected_queue)
+    end
+
+    it 'constructs round_robin_queue if queue is not present' do
+      subject.clear_queue
+      expect(subject.send(:queue)).to eq([])
+      subject.available_agent
+      # the service constructed the redis queue before performing
+      expect(subject.send(:queue).sort.map(&:to_i)).to eq(inbox_members.map(&:user_id).sort)
+    end
+
+    it 'validates the queue and correct it before performing round robin' do
+      # adding some invalid ids to queue
+      subject.add_agent_to_queue([2, 3, 5, 9])
+      expect(subject.send(:queue).sort.map(&:to_i)).not_to eq(inbox_members.map(&:user_id).sort)
+      subject.available_agent
+      # the service have refreshed the redis queue before performing
+      expect(subject.send(:queue).sort.map(&:to_i)).to eq(inbox_members.map(&:user_id).sort)
+    end
+  end
+end