## Implementation Complete ### Architectural Decision: Reuse Existing Chat Infrastructure Instead of creating a new `support_session_messages` table as originally proposed, I extended the existing chat infrastructure: - **Rationale**: User feedback that creating a new table duplicates functionality. The existing `chat_rooms` and `chat_messages` tables already handle chat well. ### Key Design Choices 1. **Chat Room per Session**: Added `support_session_id` FK to `chat_rooms` with a new `support_session` room type. 2. **Guest Messages via System User**: Created a `User.system_guest` pattern (username: `_system_guest_`) - all guest messages use this single user with their display name stored in `participant_name` column. 3. **ActionCable for Real-time**: Using ActionCable (not NATS) for operator-side chat as it's simpler and sufficient for this use case. ### Files Created - Migration: `db/migrate/20251225024032_add_support_session_chat_support.rb` - Service: `app/services/remote_support/send_chat_message_service.rb` - Controller: `app/controllers/remote_support/session_messages_controller.rb` - Channel: `app/channels/support_session_chat_channel.rb` - React: `app/javascript/components/remote_support/SessionChatPanel.jsx` ### Test Coverage - 8 service specs (all passing) - 8 request specs (all passing) - 25 existing chat model specs (all passing) - 66 support session specs (all passing) ### PR https://github.com/RoM4iK/alpha/pull/46