fix: Dedupe recent messages and wasm

.github/workflows/build-artifacts.yml

@@ -301,7 +301,7 @@ jobs:
         run: flutter pub get
 
       - name: Build web release
-        run: flutter build web --release --base-href /meshcore-sar/
+        run: flutter build web --wasm --release --base-href /meshcore-sar/
 
       - name: Upload pages artifact
         uses: actions/upload-pages-artifact@v3

Makefile

@@ -135,6 +135,9 @@ clean: ## Clean build artifacts
 	flutter clean
 	rm -rf $(BUILD_DIR)
 
+build-web: ## Build web with WebAssembly
+	flutter build web --wasm --release
+
 # Build for all platforms
 build-all: bump ## Build for Android and iOS
 	flutter build apk --release

lib/providers/messages_provider.dart

@@ -23,6 +23,7 @@ typedef DisplayMessageEntry = ({Message message, int occurrenceCount});
 /// Messages Provider - manages message history and SAR markers
 class MessagesProvider with ChangeNotifier {
   static const Duration _channelEchoWarningDelay = Duration(seconds: 12);
+  static const Duration _receivedDuplicateWindow = Duration(seconds: 5);
 
   final List<Message> _messages = [];
   final Map<String, SarMarker> _sarMarkers = {};
@@ -731,10 +732,25 @@ class MessagesProvider with ChangeNotifier {
       return -1;
     }
 
+    final exactDuplicateIndex = _findExactDuplicateMessageIndex(message);
+    if (exactDuplicateIndex != -1) {
+      return exactDuplicateIndex;
+    }
+
+    final lastConversationDuplicateIndex =
+        _findLastConversationDuplicateMessageIndex(message);
+    if (lastConversationDuplicateIndex != -1) {
+      return lastConversationDuplicateIndex;
+    }
+
+    return -1;
+  }
+
+  int _findExactDuplicateMessageIndex(Message message) {
     for (int index = 0; index < _messages.length; index++) {
       final existing = _messages[index];
       if (existing.isSentMessage ||
-          !_matchesDuplicateScope(existing, message) ||
+          !_matchesExactDuplicateScope(existing, message) ||
           existing.text != message.text) {
         continue;
       }
@@ -751,23 +767,38 @@ class MessagesProvider with ChangeNotifier {
     return -1;
   }
 
-  bool _matchesDuplicateScope(Message existing, Message message) {
+  int _findLastConversationDuplicateMessageIndex(Message message) {
+    for (int index = _messages.length - 1; index >= 0; index--) {
+      final existing = _messages[index];
+      if (!_isSameConversation(existing, message)) {
+        continue;
+      }
+      if (existing.isSentMessage ||
+          existing.isSystemMessage ||
+          existing.text != message.text) {
+        return -1;
+      }
+      final receivedDelta = existing.receivedAt.difference(message.receivedAt).abs();
+      if (receivedDelta > _receivedDuplicateWindow) {
+        return -1;
+      }
+      return _matchesDuplicateSenderIdentity(existing, message) ? index : -1;
+    }
+
+    return -1;
+  }
+
+  bool _matchesExactDuplicateScope(Message existing, Message message) {
     if (existing.messageType != message.messageType) {
       return false;
     }
 
     if (message.isContactMessage) {
-      // Match by sender key + sender timestamp (matches official app's DB
-      // uniqueness: contactPublicKey + senderTimestamp + text + txtType).
-      if (existing.senderKeyShort == message.senderKeyShort &&
-          existing.senderTimestamp == message.senderTimestamp) {
-        return true;
+      if (!_isSameConversation(existing, message)) {
+        return false;
       }
-
-      // Fallback dedup when retransmits surface as separate inbound rows
-      // without a stable timestamp/message id, but still carry the same
-      // visible sender identity and payload.
-      return _matchesDuplicateSenderIdentity(existing, message);
+      return existing.senderTimestamp == message.senderTimestamp &&
+          _matchesDuplicateSenderIdentity(existing, message);
     }
 
     if (message.isChannelMessage) {
@@ -775,24 +806,37 @@ class MessagesProvider with ChangeNotifier {
         return false;
       }
 
-      // Primary dedup: same senderTimestamp = same message from mesh repeats.
-      // Matches official app's DB uniqueness: (channelSecret, senderTimestamp, text).
       if (existing.senderTimestamp == message.senderTimestamp) {
         return true;
       }
-
-      // Secondary: catch near-duplicate repeats within a 30s window
-      // (clock drift between nodes).
-      final withinChannelRepeatWindow =
-          (existing.senderTimestamp - message.senderTimestamp).abs() <= 30;
-      if (!withinChannelRepeatWindow) {
       return false;
     }
 
-      return _matchesDuplicateSenderIdentity(existing, message);
+    // System messages and other types: never deduplicate by scope alone.
+    return false;
+  }
+
+  bool _isSameConversation(Message existing, Message message) {
+    if (existing.messageType != message.messageType) {
+      return false;
+    }
+
+    if (message.isChannelMessage) {
+      return existing.channelIdx == message.channelIdx;
+    }
+
+    if (!message.isContactMessage) {
+      return false;
+    }
+
+    if (existing.recipientPublicKey != null && message.recipientPublicKey != null) {
+      return _listEquals(existing.recipientPublicKey!, message.recipientPublicKey!);
+    }
+
+    if (existing.recipientPublicKey == null && message.recipientPublicKey == null) {
+      return true;
     }
 
-    // System messages and other types: never deduplicate by scope alone.
     return false;
   }
 
@@ -825,7 +869,7 @@ class MessagesProvider with ChangeNotifier {
         continue;
       }
 
-      if (_matchesDuplicateScope(existing, message)) {
+      if (_matchesSentReplayScope(existing, message)) {
         return index;
       }
     }
@@ -833,6 +877,24 @@ class MessagesProvider with ChangeNotifier {
     return -1;
   }
 
+  bool _matchesSentReplayScope(Message existing, Message message) {
+    if (!_isSameConversation(existing, message)) {
+      return false;
+    }
+
+    if (existing.senderTimestamp == message.senderTimestamp) {
+      return true;
+    }
+
+    final withinChannelRepeatWindow =
+        (existing.senderTimestamp - message.senderTimestamp).abs() <= 30;
+    if (!withinChannelRepeatWindow) {
+      return false;
+    }
+
+    return _matchesDuplicateSenderIdentity(existing, message);
+  }
+
   /// Add multiple messages
   void addMessages(List<Message> messages) {
     int addedCount = 0;
@@ -1254,7 +1316,9 @@ class MessagesProvider with ChangeNotifier {
     }
 
     return existing.text == message.text &&
-        _matchesDuplicateScope(existing, message);
+        (_matchesExactDuplicateScope(existing, message) ||
+            (_isSameConversation(existing, message) &&
+                _matchesDuplicateSenderIdentity(existing, message)));
   }
 
   int _messageOccurrenceCount(Message message) =>

lib/services/message_storage_service.dart

@@ -58,10 +58,7 @@ class MessageStorageService {
           : jsonList;
 
       final jsonString = jsonEncode(limitedList);
-      await prefs.setString(
-        _key(_messagesKey, namespace: namespace),
-        jsonString,
-      );
+      final messagesKey = _key(_messagesKey, namespace: namespace);
       final retainedMessageIds = limitedList
           .map((entry) => entry['id'] as String)
           .toSet();
@@ -89,22 +86,41 @@ class MessageStorageService {
           routeMetadataJson[entry.key] = entry.value.toJson();
         }
       }
-      await prefs.setString(
-        _key(_messageContactLocationsKey, namespace: namespace),
-        jsonEncode(locationJson),
+      final contactLocationsKey = _key(
+        _messageContactLocationsKey,
+        namespace: namespace,
       );
-      await prefs.setString(
-        _key(_messageReceptionDetailsKey, namespace: namespace),
-        jsonEncode(receptionJson),
+      final receptionDetailsKey = _key(
+        _messageReceptionDetailsKey,
+        namespace: namespace,
       );
-      await prefs.setString(
-        _key(_messageTransferDetailsKey, namespace: namespace),
-        jsonEncode(transferJson),
+      final transferDetailsKey = _key(
+        _messageTransferDetailsKey,
+        namespace: namespace,
       );
-      await prefs.setString(
-        _key(_messageRouteMetadataKey, namespace: namespace),
-        jsonEncode(routeMetadataJson),
+      final routeMetadataKey = _key(
+        _messageRouteMetadataKey,
+        namespace: namespace,
       );
+      final locationJsonString = jsonEncode(locationJson);
+      final receptionJsonString = jsonEncode(receptionJson);
+      final transferJsonString = jsonEncode(transferJson);
+      final routeMetadataJsonString = jsonEncode(routeMetadataJson);
+      final hasChanges =
+          prefs.getString(messagesKey) != jsonString ||
+          prefs.getString(contactLocationsKey) != locationJsonString ||
+          prefs.getString(receptionDetailsKey) != receptionJsonString ||
+          prefs.getString(transferDetailsKey) != transferJsonString ||
+          prefs.getString(routeMetadataKey) != routeMetadataJsonString;
+      if (!hasChanges) {
+        return;
+      }
+
+      await prefs.setString(messagesKey, jsonString);
+      await prefs.setString(contactLocationsKey, locationJsonString);
+      await prefs.setString(receptionDetailsKey, receptionJsonString);
+      await prefs.setString(transferDetailsKey, transferJsonString);
+      await prefs.setString(routeMetadataKey, routeMetadataJsonString);
 
       debugPrint(
         '✅ [MessageStorage] Saved ${limitedList.length} messages to storage',

test/providers/messages_provider_retransmission_test.dart

@@ -423,6 +423,133 @@ void main() {
       expect(provider.messages.single.id, equals('handle-1'));
     });
 
+    test('channel duplicates only dedupe against the latest channel message', () {
+      final provider = MessagesProvider();
+      final sender = Uint8List.fromList([9, 8, 7, 6, 5, 4]);
+
+      provider.addMessage(
+        Message(
+          id: 'channel-first',
+          messageType: MessageType.channel,
+          channelIdx: 2,
+          pathLen: 1,
+          textType: MessageTextType.plain,
+          senderTimestamp: 1700000820,
+          text: 'same payload',
+          senderName: 'Radio Alpha',
+          receivedAt: DateTime.now(),
+          senderPublicKeyPrefix: sender,
+        ),
+      );
+      provider.addMessage(
+        Message(
+          id: 'channel-middle',
+          messageType: MessageType.channel,
+          channelIdx: 2,
+          pathLen: 1,
+          textType: MessageTextType.plain,
+          senderTimestamp: 1700000825,
+          text: 'different payload',
+          senderName: 'Radio Bravo',
+          receivedAt: DateTime.now(),
+          senderPublicKeyPrefix: Uint8List.fromList([1, 2, 3, 4, 5, 6]),
+        ),
+      );
+      provider.addMessage(
+        Message(
+          id: 'channel-repeat',
+          messageType: MessageType.channel,
+          channelIdx: 2,
+          pathLen: 2,
+          textType: MessageTextType.plain,
+          senderTimestamp: 1700000830,
+          text: 'same payload',
+          senderName: 'Radio Alpha',
+          receivedAt: DateTime.now(),
+          senderPublicKeyPrefix: sender,
+        ),
+      );
+
+      expect(provider.messages, hasLength(3));
+      expect(provider.messages.last.id, equals('channel-repeat'));
+    });
+
+    test('adjacent channel duplicates still dedupe within 5 seconds', () {
+      final provider = MessagesProvider();
+      final sender = Uint8List.fromList([4, 5, 6, 7, 8, 9]);
+      final baseTime = DateTime.fromMillisecondsSinceEpoch(1700000840000);
+
+      provider.addMessage(
+        Message(
+          id: 'adjacent-1',
+          messageType: MessageType.channel,
+          channelIdx: 3,
+          pathLen: 1,
+          textType: MessageTextType.plain,
+          senderTimestamp: 1700000840,
+          text: 'same payload',
+          senderName: 'Radio Charlie',
+          receivedAt: baseTime,
+          senderPublicKeyPrefix: sender,
+        ),
+      );
+      provider.addMessage(
+        Message(
+          id: 'adjacent-2',
+          messageType: MessageType.channel,
+          channelIdx: 3,
+          pathLen: 2,
+          textType: MessageTextType.plain,
+          senderTimestamp: 1700000845,
+          text: 'same payload',
+          senderName: 'Radio Charlie',
+          receivedAt: baseTime.add(const Duration(seconds: 4)),
+          senderPublicKeyPrefix: sender,
+        ),
+      );
+
+      expect(provider.messages, hasLength(1));
+      expect(provider.messages.single.id, equals('adjacent-1'));
+    });
+
+    test('channel duplicates outside 5 second window are kept', () {
+      final provider = MessagesProvider();
+      final sender = Uint8List.fromList([6, 7, 8, 9, 0, 1]);
+      final baseTime = DateTime.fromMillisecondsSinceEpoch(1700000850000);
+
+      provider.addMessage(
+        Message(
+          id: 'window-1',
+          messageType: MessageType.channel,
+          channelIdx: 4,
+          pathLen: 1,
+          textType: MessageTextType.plain,
+          senderTimestamp: 1700000850,
+          text: 'same payload',
+          senderName: 'Radio Delta',
+          receivedAt: baseTime,
+          senderPublicKeyPrefix: sender,
+        ),
+      );
+      provider.addMessage(
+        Message(
+          id: 'window-2',
+          messageType: MessageType.channel,
+          channelIdx: 4,
+          pathLen: 2,
+          textType: MessageTextType.plain,
+          senderTimestamp: 1700000855,
+          text: 'same payload',
+          senderName: 'Radio Delta',
+          receivedAt: baseTime.add(const Duration(seconds: 6)),
+          senderPublicKeyPrefix: sender,
+        ),
+      );
+
+      expect(provider.messages, hasLength(2));
+      expect(provider.messages.last.id, equals('window-2'));
+    });
+
     test('display list collapses stored duplicates and sums copy counts', () {
       final provider = MessagesProvider();
       final sender = Uint8List.fromList([5, 4, 3, 2, 1, 0]);

test/services/message_storage_service_test.dart

@@ -1,5 +1,6 @@
 import 'dart:typed_data';
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter_test/flutter_test.dart';
 import 'package:meshcore_client/meshcore_client.dart';
 import 'package:meshcore_sar_app/models/message_reception_details.dart';
@@ -8,11 +9,16 @@ import 'package:shared_preferences/shared_preferences.dart';
 
 void main() {
   TestWidgetsFlutterBinding.ensureInitialized();
+  final originalDebugPrint = debugPrint;
 
   setUp(() {
     SharedPreferences.setMockInitialValues({});
   });
 
+  tearDown(() {
+    debugPrint = originalDebugPrint;
+  });
+
   test(
     'retains path bytes for stored unread message when reception sidecar is missing',
     () async {
@@ -155,4 +161,34 @@ void main() {
     expect(customMessages.single.id, customMessage.id);
     expect(customMessages.single.text, customMessage.text);
   });
+
+  test('skips unchanged message snapshots', () async {
+    final storage = MessageStorageService();
+    final logs = <String>[];
+    debugPrint = (String? message, {int? wrapWidth}) {
+      if (message != null) {
+        logs.add(message);
+      }
+    };
+    final message = Message(
+      id: 'msg-stable',
+      messageType: MessageType.channel,
+      senderPublicKeyPrefix: Uint8List.fromList([3, 3, 3, 3, 3, 3]),
+      channelIdx: 3,
+      pathLen: 1,
+      textType: MessageTextType.plain,
+      senderTimestamp: 1700003000,
+      text: 'Stable snapshot',
+      receivedAt: DateTime.fromMillisecondsSinceEpoch(1700003000500),
+      isRead: true,
+    );
+
+    await storage.saveMessages([message]);
+    await storage.saveMessages([message]);
+
+    expect(
+      logs.where((log) => log.contains('Saved 1 messages to storage')),
+      hasLength(1),
+    );
+  });
 }