m8chat-app2/lib/features/chat/presentation/chat_controller.dart

// Version: 1.0.0 | Created: 2026-04-01
// Riverpod providers for chat timeline.

import 'package:riverpod_annotation/riverpod_annotation.dart';

import '../data/chat_repository.dart';
import '../domain/message_model.dart';

part 'chat_controller.g.dart';

/// Streams the message list for [roomId].
@riverpod
Stream<List<MessageModel>> chatTimeline(Ref ref, String roomId) {
  final repo = ref.watch(chatRepositoryProvider);
  return repo.watchTimeline(roomId);
}

/// Sends a text message. Returns an error string on failure, null on success.
@riverpod
class SendMessage extends _$SendMessage {
  @override
  bool build() => false; // isSending

  Future<String?> send(String roomId, String text) async {
    if (text.trim().isEmpty) return null;
    state = true;
    try {
      await ref.read(chatRepositoryProvider).sendTextMessage(roomId, text);
      return null;
    } on Exception catch (e) {
      return e.toString();
    } finally {
      state = false;
    }
  }
}