Initial Commit: Duty Schedule and Attendance Logbook

lib/providers/chat_provider.dart

@@ -0,0 +1,61 @@
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:supabase_flutter/supabase_flutter.dart';
+
+import '../models/chat_message.dart';
+import 'supabase_provider.dart';
+import 'stream_recovery.dart';
+import 'realtime_controller.dart';
+
+/// Real-time chat messages for a swap request thread.
+final chatMessagesProvider = StreamProvider.family<List<ChatMessage>, String>((
+  ref,
+  threadId,
+) {
+  final client = ref.watch(supabaseClientProvider);
+
+  final wrapper = StreamRecoveryWrapper<ChatMessage>(
+    stream: client
+        .from('chat_messages')
+        .stream(primaryKey: ['id'])
+        .eq('thread_id', threadId)
+        .order('created_at'),
+    onPollData: () async {
+      final data = await client
+          .from('chat_messages')
+          .select()
+          .eq('thread_id', threadId)
+          .order('created_at');
+      return data.map(ChatMessage.fromMap).toList();
+    },
+    fromMap: ChatMessage.fromMap,
+    channelName: 'chat_messages_$threadId',
+    onStatusChanged: ref.read(realtimeControllerProvider).handleChannelStatus,
+  );
+
+  ref.onDispose(wrapper.dispose);
+  return wrapper.stream.map((result) => result.data);
+});
+
+final chatControllerProvider = Provider<ChatController>((ref) {
+  final client = ref.watch(supabaseClientProvider);
+  return ChatController(client);
+});
+
+class ChatController {
+  ChatController(this._client);
+
+  final SupabaseClient _client;
+
+  Future<void> sendMessage({
+    required String threadId,
+    required String body,
+  }) async {
+    final userId = _client.auth.currentUser?.id;
+    if (userId == null) throw Exception('Not authenticated');
+    await _client.from('chat_messages').insert({
+      'thread_id': threadId,
+      'sender_id': userId,
+      'body': body,
+    });
+  }
+}