feat: Enable Capacity Config UI (#5164)

- Enables Capacity Config in UI
- Rewrite auto assignment Logic to consider only online agents

fixes: #4990

spec/services/auto_assignment/agent_assignment_service_spec.rb

@@ -0,0 +1,38 @@
+require 'rails_helper'
+
+RSpec.describe AutoAssignment::AgentAssignmentService do
+  let!(:account) { create(:account) }
+  let!(:inbox) { create(:inbox, account: account, enable_auto_assignment: false) }
+  let!(:inbox_members) { create_list(:inbox_member, 5, inbox: inbox) }
+  let!(:conversation) { create(:conversation, inbox: inbox, account: account) }
+  let!(:online_users) do
+    {
+      inbox_members[0].user_id.to_s => 'busy',
+      inbox_members[1].user_id.to_s => 'busy',
+      inbox_members[2].user_id.to_s => 'busy',
+      inbox_members[3].user_id.to_s => 'online',
+      inbox_members[4].user_id.to_s => 'online'
+    }
+  end
+
+  before do
+    allow(::OnlineStatusTracker).to receive(:get_available_users).and_return(online_users)
+  end
+
+  describe '#perform' do
+    it 'will assign an online agent to the conversation' do
+      expect(conversation.reload.assignee).to be_nil
+      described_class.new(conversation: conversation, allowed_agent_ids: inbox_members.map(&:user_id).map(&:to_s)).perform
+      expect(conversation.reload.assignee).not_to be_nil
+    end
+  end
+
+  describe '#find_assignee' do
+    it 'will return an online agent from the allowed agent ids in roud robin' do
+      expect(described_class.new(conversation: conversation,
+                                 allowed_agent_ids: inbox_members.map(&:user_id).map(&:to_s)).find_assignee).to eq(inbox_members[3].user)
+      expect(described_class.new(conversation: conversation,
+                                 allowed_agent_ids: inbox_members.map(&:user_id).map(&:to_s)).find_assignee).to eq(inbox_members[4].user)
+    end
+  end
+end

spec/services/auto_assignment/inbox_round_robin_service_spec.rb

@@ -0,0 +1,59 @@
+require 'rails_helper'
+
+describe AutoAssignment::InboxRoundRobinService do
+  subject(:inbox_round_robin_service) { described_class.new(inbox: inbox) }
+
+  let!(:account) { create(:account) }
+  let!(:inbox) { create(:inbox, account: account) }
+  let!(:inbox_members) { create_list(:inbox_member, 5, inbox: inbox) }
+
+  describe '#available_agent' do
+    it 'returns nil if allowed_agent_ids is not passed or empty' do
+      expect(described_class.new(inbox: inbox).available_agent).to be_nil
+    end
+
+    it 'gets the first available agent in allowed_agent_ids 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)
+      described_class.new(inbox: inbox).available_agent(allowed_agent_ids: [inbox_members[0].user_id, inbox_members[4].user_id].map(&:to_s))
+      expect(inbox_round_robin_service.send(:queue)).to eq(expected_queue)
+    end
+
+    it 'constructs round_robin_queue if queue is not present' do
+      inbox_round_robin_service.clear_queue
+      expect(inbox_round_robin_service.send(:queue)).to eq([])
+      inbox_round_robin_service.available_agent
+      # the service constructed the redis queue before performing
+      expect(inbox_round_robin_service.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
+      inbox_round_robin_service.add_agent_to_queue([2, 3, 5, 9])
+      expect(inbox_round_robin_service.send(:queue).sort.map(&:to_i)).not_to eq(inbox_members.map(&:user_id).sort)
+      inbox_round_robin_service.available_agent
+      # the service have refreshed the redis queue before performing
+      expect(inbox_round_robin_service.send(:queue).sort.map(&:to_i)).to eq(inbox_members.map(&:user_id).sort)
+    end
+
+    context 'when allowed_agent_ids is passed' do
+      it 'will get the first allowed member and move it to the end of the queue' do
+        expected_queue = [inbox_members[3].user_id, inbox_members[2].user_id, inbox_members[4].user_id, inbox_members[1].user_id,
+                          inbox_members[0].user_id].map(&:to_s)
+        expect(described_class.new(inbox: inbox).available_agent(
+                 allowed_agent_ids: [
+                   inbox_members[3].user_id,
+                   inbox_members[2].user_id
+                 ].map(&:to_s)
+               )).to eq inbox_members[2].user
+        expect(described_class.new(inbox: inbox).available_agent(
+                 allowed_agent_ids: [
+                   inbox_members[3].user_id,
+                   inbox_members[2].user_id
+                 ].map(&:to_s)
+               )).to eq inbox_members[3].user
+        expect(inbox_round_robin_service.send(:queue)).to eq(expected_queue)
+      end
+    end
+  end
+end