feat: detect admin/dispute DMs in background notification pipeline

lib/core/app.dart

@@ -166,11 +166,12 @@ class _MostroAppState extends ConsumerState<MostroApp> {
         if (!_notificationLaunchHandled && _router != null) {
           _notificationLaunchHandled = true;
           WidgetsBinding.instance.addPostFrameCallback((_) async {
-            final orderId = await getNotificationLaunchOrderId();
+            final payload = await getNotificationLaunchOrderId();
             if (!mounted) return;
-            if (orderId != null && orderId.isNotEmpty) {
-              debugPrint('App launched from notification tap, navigating to order: $orderId');
-              _router!.push('/trade_detail/$orderId');
+            if (payload != null && payload.isNotEmpty) {
+              final route = resolveNotificationRoute(payload);
+              debugPrint('App launched from notification tap, navigating to: $route');
+              _router!.push(route);
             }
           });
         }

lib/features/notifications/services/background_notification_service.dart

@@ -18,6 +18,7 @@ import 'package:mostro_mobile/features/key_manager/key_derivator.dart';
 import 'package:mostro_mobile/features/key_manager/key_manager.dart';
 import 'package:mostro_mobile/features/key_manager/key_storage.dart';
 import 'package:mostro_mobile/features/notifications/utils/notification_data_extractor.dart';
+import 'package:mostro_mobile/shared/utils/nostr_utils.dart';
 import 'package:mostro_mobile/features/notifications/utils/notification_message_mapper.dart';
 import 'package:mostro_mobile/generated/l10n.dart';
 import 'package:mostro_mobile/generated/l10n_de.dart';
@@ -57,6 +58,39 @@ Future<String?> getNotificationLaunchOrderId() async {
   return null;
 }
 
+/// Resolves the navigation route from a notification payload string.
+///
+/// Returns the route path to navigate to. Pure function, no side effects.
+String resolveNotificationRoute(String? payload) {
+  if (payload == null || payload.isEmpty) {
+    return '/notifications';
+  }
+
+  try {
+    final decoded = jsonDecode(payload);
+    if (decoded is! Map<String, dynamic>) {
+      throw FormatException('Payload is not a JSON object');
+    }
+
+    final type = decoded['type'] as String?;
+    final orderId = decoded['orderId'] as String?;
+    final disputeId = decoded['disputeId'] as String?;
+
+    if (type == 'admin_dm' && orderId != null) {
+      if (disputeId != null) {
+        return '/dispute_details/$disputeId';
+      }
+      return '/trade_detail/$orderId';
+    }
+  } on FormatException {
+    // Not JSON — treat as plain orderId (legacy format)
+  } catch (e) {
+    logger.e('Unexpected error parsing notification payload: $e');
+  }
+
+  return '/trade_detail/$payload';
+}
+
 void _onNotificationTap(NotificationResponse response) {
   try {
     final context = MostroApp.navigatorKey.currentContext;
@@ -65,14 +99,9 @@ void _onNotificationTap(NotificationResponse response) {
       return;
     }
 
-    final orderId = response.payload;
-    if (orderId != null && orderId.isNotEmpty) {
-      context.push('/trade_detail/$orderId');
-      logger.i('Navigated to trade detail for order: $orderId');
-    } else {
-      context.push('/notifications');
-      logger.i('Navigated to notifications screen');
-    }
+    final route = resolveNotificationRoute(response.payload);
+    context.push(route);
+    logger.i('Navigated to: $route');
   } catch (e) {
     logger.e('Navigation error: $e');
   }
@@ -129,13 +158,18 @@ Future<void> showLocalNotification(NostrEvent event) async {
       ),
     );
 
+    // Build payload: JSON for admin DMs, plain orderId for standard notifications
+    final notificationPayload = notificationData.action == mostro_action.Action.sendDm
+        ? jsonEncode({'type': 'admin_dm', 'orderId': mostroMessage.id})
+        : mostroMessage.id;
+
     // Use fixed ID (0) with tag for replacement - Android uses tag+id combo
     await flutterLocalNotificationsPlugin.show(
       0, // Fixed ID - tag 'mostro-trade' makes it unique and replaceable
       notificationText.title,
       notificationText.body,
       details,
-      payload: mostroMessage.id,
+      payload: notificationPayload,
     );
 
     logger.i('Shown: ${notificationText.title} - ${notificationText.body}');
@@ -153,6 +187,17 @@ Future<MostroMessage?> _decryptAndProcessEvent(NostrEvent event) async {
 
     final sessions = await _loadSessionsFromDatabase();
 
+    // Try matching by adminSharedKey first (dispute chat DMs)
+    final adminSession = sessions.cast<Session?>().firstWhere(
+      (s) => s?.adminSharedKey?.public == event.recipient,
+      orElse: () => null,
+    );
+
+    if (adminSession != null) {
+      return _processAdminDm(event, adminSession);
+    }
+
+    // Standard Mostro message: match by tradeKey
     final matchingSession = sessions.cast<Session?>().firstWhere(
       (s) => s?.tradeKey.public == event.recipient,
       orElse: () => null,
@@ -172,6 +217,20 @@ Future<MostroMessage?> _decryptAndProcessEvent(NostrEvent event) async {
       return null;
     }
 
+    // Detect admin/dispute DM format that arrived via tradeKey
+    final firstItem = result[0];
+    if (NostrUtils.isDmPayload(firstItem)) {
+      if (matchingSession.orderId == null) {
+        logger.w('DM received but session has no orderId (recipient: ${event.recipient}), skipping notification');
+        return null;
+      }
+      return MostroMessage(
+        action: mostro_action.Action.sendDm,
+        id: matchingSession.orderId,
+        timestamp: event.createdAt?.millisecondsSinceEpoch,
+      );
+    }
+
     final mostroMessage = MostroMessage.fromJson(result[0]);
     mostroMessage.timestamp = event.createdAt?.millisecondsSinceEpoch;
 
@@ -182,6 +241,29 @@ Future<MostroMessage?> _decryptAndProcessEvent(NostrEvent event) async {
   }
 }
 
+Future<MostroMessage?> _processAdminDm(NostrEvent event, Session session) async {
+  try {
+    final unwrapped = await event.p2pUnwrap(session.adminSharedKey!);
+    if (unwrapped.content == null || unwrapped.content!.isEmpty) {
+      return null;
+    }
+
+    if (session.orderId == null) {
+      logger.w('Admin DM received but session has no orderId (recipient: ${event.recipient}), skipping notification');
+      return null;
+    }
+
+    return MostroMessage(
+      action: mostro_action.Action.sendDm,
+      id: session.orderId,
+      timestamp: event.createdAt?.millisecondsSinceEpoch,
+    );
+  } catch (e) {
+    logger.e('Admin DM decrypt error: $e');
+    return null;
+  }
+}
+
 Future<List<Session>> _loadSessionsFromDatabase() async {
   try {
     final db = await openMostroDatabase('mostro.db');

lib/features/notifications/utils/notification_data_extractor.dart

@@ -177,20 +177,28 @@ class NotificationDataExtractor {
         // No additional values needed
         break;
 
+      case Action.sendDm:
+        // Admin/dispute DM — no payload extraction needed, generic message
+        break;
+
+      case Action.cooperativeCancelAccepted:
+        // No additional values needed
+        break;
+
       case Action.cantDo:
         final cantDo = event.getPayload<CantDo>();
         values['reason'] = cantDo?.cantDoReason.toString();
         isTemporary = true; // cantDo notifications are temporary
         break;
-        
+
       case Action.rate:
         // No additional values needed
         break;
-        
+
       case Action.rateReceived:
         // This action doesn't generate notifications
         return null;
-        
+
       default:
         // Unknown actions generate temporary notifications
         isTemporary = true;

lib/features/notifications/utils/notification_message_mapper.dart

@@ -70,7 +70,7 @@ class NotificationMessageMapper {
       case mostro.Action.cooperativeCancelAccepted:
         return 'notification_cooperative_cancel_accepted_title';
       case mostro.Action.sendDm:
-        return 'notification_new_message_title';
+        return 'notification_admin_message_title';
       case mostro.Action.cancel:
       case mostro.Action.adminCancel:
       case mostro.Action.adminCanceled:
@@ -166,7 +166,7 @@ class NotificationMessageMapper {
       case mostro.Action.cooperativeCancelAccepted:
         return 'notification_cooperative_cancel_accepted_message';
       case mostro.Action.sendDm:
-        return 'notification_new_message_message';
+        return 'notification_admin_message_message';
       case mostro.Action.cancel:
       case mostro.Action.adminCancel:
       case mostro.Action.adminCanceled:
@@ -330,6 +330,10 @@ class NotificationMessageMapper {
         return s.notification_new_message_title;
       case 'notification_new_message_message':
         return s.notification_new_message_message;
+      case 'notification_admin_message_title':
+        return s.notification_admin_message_title;
+      case 'notification_admin_message_message':
+        return s.notification_admin_message_message;
       case 'notification_order_update_title':
         return s.notification_order_update_title;
       case 'notification_order_update_message':

lib/features/subscriptions/subscription_manager.dart

@@ -23,10 +23,12 @@ class SubscriptionManager {
 
   final _ordersController = StreamController<NostrEvent>.broadcast();
   final _chatController = StreamController<NostrEvent>.broadcast();
+  final _disputeChatController = StreamController<NostrEvent>.broadcast();
   final _relayListController = StreamController<RelayListEvent>.broadcast();
 
   Stream<NostrEvent> get orders => _ordersController.stream;
   Stream<NostrEvent> get chat => _chatController.stream;
+  Stream<NostrEvent> get disputeChat => _disputeChatController.stream;
   Stream<RelayListEvent> get relayList => _relayListController.stream;
 
   SubscriptionManager(this.ref) {
@@ -141,6 +143,16 @@ class SubscriptionManager {
               .map((s) => s.sharedKey!.public)
               .toList(),
         );
+      case SubscriptionType.disputeChat:
+        final adminKeys = sessions
+            .where((s) => s.adminSharedKey?.public != null)
+            .map((s) => s.adminSharedKey!.public)
+            .toList();
+        if (adminKeys.isEmpty) return null;
+        return NostrFilter(
+          kinds: [1059],
+          p: adminKeys,
+        );
       case SubscriptionType.relayList:
         // Relay list subscriptions are handled separately via subscribeToMostroRelayList
         return null;
@@ -156,6 +168,9 @@ class SubscriptionManager {
         case SubscriptionType.chat:
           _chatController.add(event);
           break;
+        case SubscriptionType.disputeChat:
+          _disputeChatController.add(event);
+          break;
         case SubscriptionType.relayList:
           final relayListEvent = RelayListEvent.fromEvent(event);
           if (relayListEvent != null) {
@@ -207,6 +222,8 @@ class SubscriptionManager {
         return orders;
       case SubscriptionType.chat:
         return chat;
+      case SubscriptionType.disputeChat:
+        return disputeChat;
       case SubscriptionType.relayList:
         // RelayList subscriptions should use subscribeToMostroRelayList() instead
         throw UnsupportedError('Use subscribeToMostroRelayList() for relay list subscriptions');
@@ -328,6 +345,7 @@ class SubscriptionManager {
     unsubscribeAll();
     _ordersController.close();
     _chatController.close();
+    _disputeChatController.close();
     _relayListController.close();
   }
 }

lib/features/subscriptions/subscription_type.dart

@@ -1,5 +1,6 @@
 enum SubscriptionType {
   chat,
   orders,
+  disputeChat,
   relayList,
 }

lib/l10n/intl_de.arb

@@ -1176,6 +1176,8 @@
     "notification_cant_do_message": "Die angeforderte Aktion kann nicht ausgeführt werden",
     "notification_new_message_title": "Neue Nachricht",
     "notification_new_message_message": "Du hast eine neue Nachricht erhalten",
+    "notification_admin_message_title": "Nachricht vom Administrator",
+    "notification_admin_message_message": "Du hast eine Nachricht vom Streitadministrator erhalten",
     "notification_order_update_title": "Order-Update",
     "notification_order_update_message": "Deine Order wurde aktualisiert",
     "@_comment_notification_details": "Labels für Benachrichtigungsdetails",

lib/l10n/intl_en.arb

@@ -1176,6 +1176,8 @@
     "notification_cant_do_message": "The requested action cannot be performed",
     "notification_new_message_title": "New message",
     "notification_new_message_message": "You have received a new message",
+    "notification_admin_message_title": "Message from admin",
+    "notification_admin_message_message": "You have received a message from the dispute admin",
     "notification_order_update_title": "Order update",
     "notification_order_update_message": "Your order has been updated",
     "@_comment_notification_details": "Notification details labels",

lib/l10n/intl_es.arb

@@ -1090,6 +1090,8 @@
     "notification_cant_do_message": "La acción solicitada no se puede realizar",
     "notification_new_message_title": "Nuevo mensaje",
     "notification_new_message_message": "Has recibido un nuevo mensaje",
+    "notification_admin_message_title": "Mensaje del administrador",
+    "notification_admin_message_message": "Has recibido un mensaje del administrador de la disputa",
     "notification_order_update_title": "Actualización de orden",
     "notification_order_update_message": "Tu orden ha sido actualizada",
     "@_comment_notification_details": "Etiquetas de detalles de notificaciones",

lib/l10n/intl_fr.arb

@@ -1176,6 +1176,8 @@
     "notification_cant_do_message": "L'action demandée ne peut pas être effectuée",
     "notification_new_message_title": "Nouveau message",
     "notification_new_message_message": "Vous avez reçu un nouveau message",
+    "notification_admin_message_title": "Message de l'administrateur",
+    "notification_admin_message_message": "Vous avez reçu un message de l'administrateur du litige",
     "notification_order_update_title": "Mise à jour de commande",
     "notification_order_update_message": "Votre commande a été mise à jour",
     "@_comment_notification_details": "Notification details labels",

lib/l10n/intl_it.arb

@@ -1149,6 +1149,8 @@
     "notification_cant_do_message": "L'azione richiesta non può essere eseguita",
     "notification_new_message_title": "Nuovo messaggio",
     "notification_new_message_message": "Hai ricevuto un nuovo messaggio",
+    "notification_admin_message_title": "Messaggio dall'amministratore",
+    "notification_admin_message_message": "Hai ricevuto un messaggio dall'amministratore della disputa",
     "notification_order_update_title": "Aggiornamento ordine",
     "notification_order_update_message": "Il tuo ordine è stato aggiornato",
     "@_comment_notification_details": "Etichette dei dettagli delle notifiche",

lib/services/mostro_service.dart

@@ -14,6 +14,7 @@ import 'package:mostro_mobile/features/settings/settings_provider.dart';
 import 'package:mostro_mobile/features/order/providers/order_notifier_provider.dart';
 import 'package:mostro_mobile/features/key_manager/key_manager_provider.dart';
 import 'package:mostro_mobile/features/mostro/mostro_instance.dart';
+import 'package:mostro_mobile/shared/utils/nostr_utils.dart';
 
 class MostroService {
   final Ref ref;
@@ -105,6 +106,8 @@ class MostroService {
     final eventStore = ref.read(eventStorageProvider);
 
     if (await eventStore.hasItem(event.id!)) return;
+
+    // Reserve event ID immediately to prevent duplicate processing from multiple relays
     await eventStore.putItem(event.id!, {
       'id': event.id,
       'created_at': event.createdAt!.millisecondsSinceEpoch ~/ 1000,
@@ -133,6 +136,13 @@ class MostroService {
         return;
       }
 
+      // Skip dispute chat DMs — DisputeChatNotifier handles these
+      // via its own adminSharedKey subscription
+      if (NostrUtils.isDmPayload(result[0])) {
+        logger.i('Skipping dispute chat message (handled by DisputeChatNotifier)');
+        return;
+      }
+
       // Skip restore-specific payloads that arrive as historical events due to temporary subscription
       if (result[0] is Map &&
           _isRestorePayload(result[0] as Map<String, dynamic>)) {

lib/shared/utils/nostr_utils.dart

@@ -444,6 +444,19 @@ class NostrUtils {
     }
   }
 
+  /// Checks if a decoded Mostro payload item is a DM (dispute/admin chat) message.
+  /// DM messages use the format: {"dm": {"action": "send-dm", "payload": {...}}}
+  /// Validates shape strictly to avoid false positives from other payloads.
+  static bool isDmPayload(dynamic item) {
+    if (item is! Map) return false;
+    final dm = item['dm'];
+    if (dm is! Map) return false;
+    if (dm['action'] != 'send-dm') return false;
+    final payload = dm['payload'];
+    if (payload is! Map) return false;
+    return true;
+  }
+
   static Future<String> encryptNIP44(
     String content,
     String privkey,