Merge branch 'main' into dev-mapOverlap

.gitignore

@@ -58,6 +58,7 @@ secrets.dart
 .DS_Store
 .AppleDouble
 .LSOverride
+macos/Flutter/GeneratedPluginRegistrant.swift
 
 # iOS
 **/ios/Pods/
@@ -85,4 +86,4 @@ keystore.properties
 .vscode/settings.json
 
 # Cloudflare Wrangler
-.wrangler
+.wrangler

lib/connector/meshcore_connector.dart

@@ -257,6 +257,9 @@ class MeshCoreConnector extends ChangeNotifier {
   int? _activeChannelIndex;
   List<int> _channelOrder = [];
 
+  int _storageUsedKb = -1;
+  int _storageTotalKb = -1;
+
   // Getters
   MeshCoreConnectionState get state => _state;
   BluetoothDevice? get device => _device;
@@ -338,6 +341,8 @@ class MeshCoreConnector extends ChangeNotifier {
   int? get firmwareVerCode => _firmwareVerCode;
   Map<String, String>? get currentCustomVars => _currentCustomVars;
   int? get batteryMillivolts => _batteryMillivolts;
+  int? get storageUsedKb => _storageUsedKb;
+  int? get storageTotalKb => _storageTotalKb;
   int get maxContacts => _maxContacts;
   int get maxChannels => _maxChannels;
   Set<String> get knownContactKeys => Set.unmodifiable(_knownContactKeys);
@@ -2122,9 +2127,7 @@ class MeshCoreConnector extends ChangeNotifier {
       outboundText,
       selfKey,
     );
-    final ackHashHex = ackHash
+    final ackHashHex = ackHashToHex(ackHash);
-        .map((b) => b.toRadixString(16).padLeft(2, '0'))
-        .join();
     final messageBytes = utf8.encode(outboundText).length;
     _pendingRepeaterAcks[ackHashHex]?.timeout?.cancel();
     _pendingRepeaterAcks[ackHashHex] = _RepeaterAckContext(
@@ -2896,7 +2899,7 @@ class MeshCoreConnector extends ChangeNotifier {
       _currentSf = reader.readByte();
       _currentCr = reader.readByte();
 
-      _selfName = reader.readString();
+      _selfName = reader.readCString();
     } catch (e) {
       _appDebugLogService?.error(
         'Error parsing SELF_INFO frame: $e',
@@ -3037,14 +3040,23 @@ class MeshCoreConnector extends ChangeNotifier {
     // [1-2] = battery_mv (uint16 LE)
     // [3-6] = storage_used_kb (uint32 LE)
     // [7-10] = storage_total_kb (uint32 LE)
-    if (frame.length >= 3) {
+    try {
-      _batteryMillivolts = readUint16LE(frame, 1);
+      final reader = BufferReader(frame);
+      reader.skipBytes(1);
+      _batteryMillivolts = reader.readUInt16LE();
+      _storageUsedKb = reader.readUInt32LE();
+      _storageTotalKb = reader.readUInt32LE();
       final volts = (_batteryMillivolts! / 1000.0).toStringAsFixed(2);
       _appDebugLogService?.info(
         'Pulled battery: $volts V ($_batteryMillivolts mV)',
         tag: 'Battery',
       );
       notifyListeners();
+    } catch (e) {
+      _appDebugLogService?.error(
+        'Error parsing battery and storage frame: $e',
+        tag: 'Connector',
+      );
     }
   }
 
@@ -3540,7 +3552,7 @@ class MeshCoreConnector extends ChangeNotifier {
         reader.skipBytes(4); // Skip extra 4 bytes for signed/plain variants
       }
 
-      final msgText = reader.readString();
+      final msgText = reader.readCString();
 
       final flags = txtType;
       final shiftedType = flags >> 2;
@@ -3702,68 +3714,87 @@ class MeshCoreConnector extends ChangeNotifier {
 
   void _handleLogRxData(Uint8List frame) {
     if (frame.length < 4) return;
-    final raw = Uint8List.fromList(frame.sublist(3));
+    try {
-    final packet = _parseRawPacket(raw);
+      final reader = BufferReader(frame);
-    if (packet == null || packet.payloadType != _payloadTypeGroupText) return;
+      reader.skipBytes(3); // Skip header
 
-    final payload = packet.payload;
+      final raw = reader.readRemainingBytes();
-    if (payload.length <= _cipherMacSize) return;
+      final packet = _parseRawPacket(raw);
-    final channelHash = payload[0];
+      if (packet == null || packet.payloadType != _payloadTypeGroupText) return;
-    final encrypted = Uint8List.fromList(payload.sublist(1));
 
-    // Use cached channels as fallback if live channels not yet loaded
+      final payload = BufferReader(packet.payload);
-    final channelsToSearch = _channels.isNotEmpty ? _channels : _cachedChannels;
+      final channelHash = payload.readByte();
-    for (final channel in channelsToSearch) {
+      final encrypted = Uint8List.fromList(payload.readRemainingBytes());
-      if (channel.isEmpty) continue;
-      final hash = _computeChannelHash(channel.psk);
-      if (hash != channelHash) continue;
 
-      final decrypted = _decryptPayload(channel.psk, encrypted);
+      // Use cached channels as fallback if live channels not yet loaded
-      if (decrypted == null || decrypted.length < 6) return;
+      final channelsToSearch = _channels.isNotEmpty
+          ? _channels
+          : _cachedChannels;
+      for (final channel in channelsToSearch) {
+        if (channel.isEmpty) continue;
+        final hash = _computeChannelHash(channel.psk);
+        if (hash != channelHash) continue;
+        try {
+          final decryptedBytes = _decryptPayload(channel.psk, encrypted);
+          if (decryptedBytes == null || decryptedBytes.length < 6) return;
+          final decrypted = BufferReader(decryptedBytes);
 
-      final txtType = decrypted[4];
+          final timestampRaw = decrypted.readUInt32LE();
-      if ((txtType >> 2) != 0) {
+          final txtType = decrypted.readByte();
-        return;
+          if ((txtType >> 2) != 0) {
+            return;
+          }
+
+          final text = decrypted.readCString();
+          final parsed = _splitSenderText(text);
+          final decodedText =
+              Smaz.tryDecodePrefixed(parsed.text) ?? parsed.text;
+          if (_shouldDropSelfChannelMessage(
+            parsed.senderName,
+            packet.pathBytes,
+          )) {
+            return;
+          }
+
+          final pktHash = _computePacketHash(
+            packet.payloadType,
+            packet.payload,
+          );
+
+          final message = ChannelMessage(
+            senderKey: null,
+            senderName: parsed.senderName,
+            text: decodedText,
+            timestamp: DateTime.fromMillisecondsSinceEpoch(timestampRaw * 1000),
+            isOutgoing: false,
+            status: ChannelMessageStatus.sent,
+            pathLength: packet.isFlood ? packet.hopCount : 0,
+            pathBytes: packet.pathBytes,
+            channelIndex: channel.index,
+            packetHash: pktHash,
+          );
+
+          _updateContactLastMessageAtByName(
+            parsed.senderName,
+            message.timestamp,
+            pathBytes: message.pathBytes,
+          );
+          final isNew = _addChannelMessage(channel.index, message);
+          _maybeIncrementChannelUnread(message, isNew: isNew);
+          notifyListeners();
+          if (isNew) {
+            final label = channel.name.isEmpty
+                ? 'Channel ${channel.index}'
+                : channel.name;
+            _maybeNotifyChannelMessage(message, channelName: label);
+          }
+          return;
+        } catch (e) {
+          appLogger.warn('Decryption failed for channel ${channel.index}: $e');
+        }
       }
-
+    } catch (e) {
-      final timestampRaw = readUint32LE(decrypted, 0);
+      appLogger.warn('Error handling log RX data frame: $e');
-      final text = readCString(decrypted, 5, decrypted.length - 5);
-      final parsed = _splitSenderText(text);
-      final decodedText = Smaz.tryDecodePrefixed(parsed.text) ?? parsed.text;
-      if (_shouldDropSelfChannelMessage(parsed.senderName, packet.pathBytes)) {
-        return;
-      }
-
-      final pktHash = _computePacketHash(packet.payloadType, packet.payload);
-
-      final message = ChannelMessage(
-        senderKey: null,
-        senderName: parsed.senderName,
-        text: decodedText,
-        timestamp: DateTime.fromMillisecondsSinceEpoch(timestampRaw * 1000),
-        isOutgoing: false,
-        status: ChannelMessageStatus.sent,
-        pathLength: packet.isFlood ? packet.hopCount : 0,
-        pathBytes: packet.pathBytes,
-        channelIndex: channel.index,
-        packetHash: pktHash,
-      );
-
-      _updateContactLastMessageAtByName(
-        parsed.senderName,
-        message.timestamp,
-        pathBytes: message.pathBytes,
-      );
-      final isNew = _addChannelMessage(channel.index, message);
-      _maybeIncrementChannelUnread(message, isNew: isNew);
-      notifyListeners();
-      if (isNew) {
-        final label = channel.name.isEmpty
-            ? 'Channel ${channel.index}'
-            : channel.name;
-        _maybeNotifyChannelMessage(message, channelName: label);
-      }
-      return;
     }
   }
 
@@ -3774,15 +3805,15 @@ class MeshCoreConnector extends ChangeNotifier {
     // [2-5] = expected_ack_hash (uint32)
     // [6-9] = estimated_timeout_ms (uint32)
 
-    if (frame.length >= 10) {
+    try {
-      final ackHash = Uint8List.fromList(frame.sublist(2, 6));
+      final reader = BufferReader(frame);
-      final timeoutMs = readUint32LE(frame, 6);
+      reader.skipBytes(2); //Skip code and is_flood
+      final ackHash = reader.readUInt32LE();
+      final timeoutMs = reader.readUInt32LE();
 
       // Check if this is a CLI command ACK - if so, ignore it
       if (_lastSentWasCliCommand) {
-        final ackHashHex = ackHash
+        final ackHashHex = ackHashToHex(ackHash);
-            .map((b) => b.toRadixString(16).padLeft(2, '0'))
-            .join();
         debugPrint('Ignoring CLI command ACK (sent): $ackHashHex');
         _lastSentWasCliCommand = false;
         return;
@@ -3801,7 +3832,8 @@ class MeshCoreConnector extends ChangeNotifier {
       if (_markNextPendingChannelMessageSent()) {
         return;
       }
-    } else {
+    } catch (e) {
+      appLogger.warn('Error handling message sent frame: $e');
       // Fallback to old behavior
       for (var messages in _conversations.values) {
         for (int i = messages.length - 1; i >= 0; i--) {
@@ -3880,9 +3912,11 @@ class MeshCoreConnector extends ChangeNotifier {
     // [1-4] = ack_hash (uint32)
     // [5-8] = trip_time_ms (uint32)
 
-    if (frame.length >= 9) {
+    try {
-      final ackHash = Uint8List.fromList(frame.sublist(1, 5));
+      final reader = BufferReader(frame);
-      final tripTimeMs = readUint32LE(frame, 5);
+      reader.skipBytes(1); // Skip code
+      final ackHash = reader.readUInt32LE();
+      final tripTimeMs = reader.readUInt32LE();
 
       // CLI command ACKs are already filtered in _handleMessageSent, so this should only see real messages
 
@@ -3894,7 +3928,8 @@ class MeshCoreConnector extends ChangeNotifier {
       if (_retryService != null) {
         _retryService!.handleAckReceived(ackHash, tripTimeMs);
       }
-    } else {
+    } catch (e) {
+      appLogger.warn('Error handling send confirmed frame: $e');
       // Fallback to old behavior
       for (var messages in _conversations.values) {
         for (int i = messages.length - 1; i >= 0; i--) {
@@ -3909,10 +3944,8 @@ class MeshCoreConnector extends ChangeNotifier {
     }
   }
 
-  bool _handleRepeaterCommandSent(Uint8List ackHash, int timeoutMs) {
+  bool _handleRepeaterCommandSent(int ackHash, int timeoutMs) {
-    final ackHashHex = ackHash
+    final ackHashHex = ackHashToHex(ackHash);
-        .map((b) => b.toRadixString(16).padLeft(2, '0'))
-        .join();
     final entry = _pendingRepeaterAcks[ackHashHex];
     if (entry == null) return false;
 
@@ -3930,10 +3963,8 @@ class MeshCoreConnector extends ChangeNotifier {
     return true;
   }
 
-  bool _handleRepeaterCommandAck(Uint8List ackHash, int tripTimeMs) {
+  bool _handleRepeaterCommandAck(int ackHash, int tripTimeMs) {
-    final ackHashHex = ackHash
+    final ackHashHex = ackHashToHex(ackHash);
-        .map((b) => b.toRadixString(16).padLeft(2, '0'))
-        .join();
     final entry = _pendingRepeaterAcks.remove(ackHashHex);
     if (entry == null) return false;
     entry.timeout?.cancel();
@@ -4284,36 +4315,35 @@ class MeshCoreConnector extends ChangeNotifier {
   }
 
   _RawPacket? _parseRawPacket(Uint8List raw) {
-    if (raw.length < 3) return null;
+    try {
-    var index = 0;
+      final reader = BufferReader(raw);
-    final header = raw[index++];
+      final header = reader.readByte();
-    final routeType = header & _phRouteMask;
+      final routeType = header & _phRouteMask;
-    final hasTransport =
+      final hasTransport =
-        routeType == _routeTransportFlood || routeType == _routeTransportDirect;
+          routeType == _routeTransportFlood ||
-    if (hasTransport) {
+          routeType == _routeTransportDirect;
-      if (raw.length < index + 4) return null;
+      if (hasTransport) {
-      index += 4;
+        // Skip reserved bytes in transport header made up of two u16 fields
-    }
+        reader.skipBytes(4);
-    if (raw.length <= index) return null;
+      }
-    final pathLenRaw = raw[index++];
+      final pathLenRaw = reader.readByte();
-    final pathByteLen = _decodePathByteLen(pathLenRaw);
+      final pathByteLen = _decodePathByteLen(pathLenRaw);
-    if (raw.length < index + pathByteLen) return null;
+      final pathBytes = reader.readBytes(pathByteLen);
-    final pathBytes = Uint8List.fromList(
+      final payload = reader.readBytes(reader.remaining);
-      raw.sublist(index, index + pathByteLen),
-    );
-    index += pathByteLen;
-    if (raw.length <= index) return null;
-    final payload = Uint8List.fromList(raw.sublist(index));
 
-    return _RawPacket(
+      return _RawPacket(
-      header: header,
+        header: header,
-      routeType: routeType,
+        routeType: routeType,
-      payloadType: (header >> _phTypeShift) & _phTypeMask,
+        payloadType: (header >> _phTypeShift) & _phTypeMask,
-      payloadVer: (header >> _phVerShift) & _phVerMask,
+        payloadVer: (header >> _phVerShift) & _phVerMask,
-      pathLenRaw: pathLenRaw,
+        pathLenRaw: pathLenRaw,
-      pathBytes: pathBytes,
+        pathBytes: pathBytes,
-      payload: payload,
+        payload: payload,
-    );
+      );
+    } catch (e) {
+      appLogger.warn('Error parsing raw packet: $e');
+      return null;
+    }
   }
 
   int _computeChannelHash(Uint8List psk) {
@@ -4732,7 +4762,7 @@ class MeshCoreConnector extends ChangeNotifier {
   void _handleCustomVars(Uint8List frame) {
     final buf = BufferReader(frame.sublist(1));
     try {
-      _currentCustomVars = _parseKeyValueString(buf.readString());
+      _currentCustomVars = _parseKeyValueString(buf.readCString());
     } catch (e) {
       appLogger.warn('Malformed custom vars frame: $e', tag: 'Connector');
     }
@@ -4889,7 +4919,7 @@ class MeshCoreConnector extends ChangeNotifier {
         longitude = packet.readInt32LE() / 1e6;
       }
       if (hasName && packet.remaining > 0) {
-        name = packet.readString();
+        name = packet.readCString();
       }
     } catch (e) {
       appLogger.warn('Malformed advert frame: $e', tag: 'Connector');
@@ -4965,7 +4995,7 @@ class MeshCoreConnector extends ChangeNotifier {
       hasLocation = hasValidLocation(latitude, longitude);
 
       if (hasName && advert.remaining > 0) {
-        name = advert.readString();
+        name = advert.readCString();
       }
     } catch (e) {
       appLogger.warn('Malformed advert frame: $e', tag: 'Connector');

lib/connector/meshcore_protocol.dart

@@ -1,6 +1,8 @@
 import 'dart:convert';
 import 'dart:typed_data';
 
+import 'package:flutter/widgets.dart';
+
 // Buffer Reader - sequential binary data reader with pointer tracking
 class BufferReader {
   int _pointer = 0;
@@ -37,16 +39,6 @@ class BufferReader {
 
   Uint8List readRemainingBytes() => readBytes(remaining);
 
-  String readString() {
-    _lastPointer = _pointer;
-    final value = readRemainingBytes();
-    try {
-      return utf8.decode(Uint8List.fromList(value), allowMalformed: true);
-    } catch (e) {
-      return String.fromCharCodes(value); // Latin-1 fallback
-    }
-  }
-
   String readCStringGreedy(int maxLength) {
     _lastPointer = _pointer;
     final value = <int>[];
@@ -62,11 +54,12 @@ class BufferReader {
     }
   }
 
-  String readCString(int maxLength) {
+  String readCString({int maxLength = -1}) {
     final backupPointer = _pointer;
     final value = <int>[];
     int counter = 0;
-    while (counter < maxLength) {
+    final maxLen = maxLength >= 0 ? maxLength : remaining;
+    while (counter < maxLen) {
       final byte = readByte();
       if (byte == 0) break;
       value.add(byte);
@@ -220,6 +213,7 @@ const int cmdGetAutoAddConfig = 59;
 // Text message types
 const int txtTypePlain = 0;
 const int txtTypeCliData = 1;
+const int txtTypeSigned = 2;
 
 // Repeater request types (for server requests)
 const int reqTypeGetStatus = 0x01;
@@ -314,6 +308,7 @@ const int autoAddSensorFlag =
 
 // Sizes
 const int pubKeySize = 32;
+const int signatureSize = 64;
 const int maxPathSize = 64;
 const int pathHashSize = 1;
 const int maxNameSize = 32;
@@ -377,52 +372,44 @@ const int msgTextOffset = 38;
 class ParsedContactText {
   final Uint8List senderPrefix;
   final String text;
-
   const ParsedContactText({required this.senderPrefix, required this.text});
 }
 
 ParsedContactText? parseContactMessageText(Uint8List frame) {
   if (frame.isEmpty) return null;
-  final code = frame[0];
+
-  if (code != respCodeContactMsgRecv && code != respCodeContactMsgRecvV3) {
+  final message = BufferReader(frame);
+  try {
+    final code = message.readByte();
+    if (code != respCodeContactMsgRecv && code != respCodeContactMsgRecvV3) {
+      return null;
+    }
+
+    // Companion radio layout:
+    // [code][snr?][res?][res?][prefix x6][path_len][txt_type][timestamp x4][extra?][text...]
+    if (code == respCodeContactMsgRecvV3) {
+      // Skip SNR and reserved bytes in v3 layout
+      message.skipBytes(3);
+    }
+    final senderPrefix = message.readBytes(6); // public key
+    message.skipBytes(1); // path length
+    final textType = message.readByte();
+    message.skipBytes(4); // timestamp (4 bytes)
+
+    final shiftedType = textType >> 2;
+    final isSigned = shiftedType == txtTypeSigned || textType == txtTypeSigned;
+    if (isSigned) {
+      // Signed messages have a 4-byte signature after the timestamp, before the text
+      message.skipBytes(4);
+    }
+    final text = message.readCString();
+    if (text.isEmpty) return null;
+
+    return ParsedContactText(senderPrefix: senderPrefix, text: text);
+  } catch (e) {
+    debugPrint('Error parsing contact message text: $e');
     return null;
   }
-
-  // Companion radio layout:
-  // [code][snr?][res?][res?][prefix x6][path_len][txt_type][timestamp x4][extra?][text...]
-  final isV3 = code == respCodeContactMsgRecvV3;
-  final prefixOffset = isV3 ? 4 : 1;
-  const prefixLen = 6;
-  final txtTypeOffset = prefixOffset + prefixLen + 1;
-  final timestampOffset = txtTypeOffset + 1;
-  final baseTextOffset = timestampOffset + 4;
-  if (frame.length <= baseTextOffset) return null;
-
-  final flags = frame[txtTypeOffset];
-  final shiftedType = flags >> 2;
-  final rawType = flags;
-  final isPlain = shiftedType == txtTypePlain || rawType == txtTypePlain;
-  final isCli = shiftedType == txtTypeCliData || rawType == txtTypeCliData;
-  if (!isPlain && !isCli) {
-    return null;
-  }
-
-  var text = readCString(
-    frame,
-    baseTextOffset,
-    frame.length - baseTextOffset,
-  ).trim();
-  if (text.isEmpty && frame.length > baseTextOffset + 4) {
-    text = readCString(
-      frame,
-      baseTextOffset + 4,
-      frame.length - (baseTextOffset + 4),
-    ).trim();
-  }
-  if (text.isEmpty) return null;
-
-  final senderPrefix = frame.sublist(prefixOffset, prefixOffset + prefixLen);
-  return ParsedContactText(senderPrefix: senderPrefix, text: text);
 }
 
 // Helper to read uint32 little-endian
@@ -445,18 +432,9 @@ int readInt32LE(Uint8List data, int offset) {
   return val;
 }
 
-// Helper to read null-terminated UTF-8 string
+// Helper to convert uint32 to hex string
-String readCString(Uint8List data, int offset, int maxLen) {
+String ackHashToHex(int ackHash) {
-  int end = offset;
+  return ackHash.toRadixString(16).padLeft(8, '0');
-  while (end < offset + maxLen && end < data.length && data[end] != 0) {
-    end++;
-  }
-  try {
-    return utf8.decode(data.sublist(offset, end), allowMalformed: true);
-  } catch (e) {
-    // Fallback to Latin-1 if UTF-8 decoding fails
-    return String.fromCharCodes(data.sublist(offset, end));
-  }
 }
 
 // Helper to convert public key to hex string

lib/l10n/app_bg.arb

@@ -1892,7 +1892,7 @@
   "map_setAsMyLocation": "Задайте като моя местоположение",
   "@path_routeWeight": {
     "placeholders": {
-      "value": {
+      "weight": {
         "type": "String"
       },
       "max": {

lib/models/channel.dart

@@ -24,20 +24,23 @@ class Channel {
 
   bool get isPublicChannel => pskHex == publicChannelPsk;
 
-  static Channel? fromFrame(Uint8List data) {
+  static Channel? fromFrame(Uint8List frame) {
     // CHANNEL_INFO format:
     // [0] = RESP_CODE_CHANNEL_INFO (18)
     // [1] = channel_idx
     // [2-33] = name (32 bytes, null-terminated)
     // [34-49] = psk (16 bytes)
-    if (data.length < 50) return null;
+    if (frame.length < 50) return null;
-    if (data[0] != respCodeChannelInfo) return null;
+    final reader = BufferReader(frame);
-
+    try {
-    final index = data[1];
+      if (reader.readByte() != respCodeChannelInfo) return null;
-    final name = readCString(data, 2, 32);
+      final index = reader.readByte();
-    final psk = Uint8List.fromList(data.sublist(34, 50));
+      final name = reader.readCStringGreedy(32);
-
+      final psk = reader.readBytes(16);
-    return Channel(index: index, name: name, psk: psk);
+      return Channel(index: index, name: name, psk: psk);
+    } catch (e) {
+      return null;
+    }
   }
 
   static Channel empty(int index) {

lib/models/channel_message.dart

@@ -2,6 +2,7 @@ import 'dart:typed_data';
 import '../connector/meshcore_protocol.dart';
 import '../helpers/reaction_helper.dart';
 import '../helpers/smaz.dart';
+import '../utils/app_logger.dart';
 
 enum ChannelMessageStatus { pending, sent, failed }
 
@@ -109,89 +110,82 @@ class ChannelMessage {
     );
   }
 
-  static ChannelMessage? fromFrame(Uint8List data) {
+  static ChannelMessage? fromFrame(Uint8List frame) {
     // CHANNEL_MSG_RECV format varies by version:
     // V3: [0]=code [1]=SNR [2]=rsv1 [3]=rsv2 [4]=channel_idx [5]=path_len [path... optional] [txt_type] [timestamp x4] [text...]
     // Non-V3: [0]=code [1]=channel_idx [2]=path_len [3]=txt_type [4-7]=timestamp [8+]=text
-    if (data.length < 8) return null;
+    if (frame.length < 8) return null;
+    try {
+      final reader = BufferReader(frame);
+      final code = reader.readByte();
+      if (code != respCodeChannelMsgRecv && code != respCodeChannelMsgRecvV3) {
+        return null;
+      }
 
-    final code = data[0];
+      int pathLen;
-    if (code != respCodeChannelMsgRecv && code != respCodeChannelMsgRecvV3) {
+      int txtType;
+      Uint8List pathBytes = Uint8List(0);
+      int channelIdx;
+      if (code == respCodeChannelMsgRecvV3) {
+        reader.skipBytes(1); // Skip SNR
+        final flags = reader.readByte();
+        final hasPath = (flags & 0x01) != 0;
+        reader.skipBytes(1); // Skip reserved byte
+        channelIdx = reader.readByte();
+        pathLen = reader.readInt8();
+        txtType = reader.readByte();
+        if (hasPath && pathLen > 0) {
+          reader.rewind(); // Rewind to read path length again for pathBytes
+          pathBytes = reader.readBytes(pathLen);
+        }
+      } else {
+        channelIdx = reader.readByte();
+        pathLen = reader.readInt8();
+        txtType = reader.readByte();
+      }
+      final timestampRaw = reader.readUInt32LE();
+
+      if (txtType != txtTypePlain) {
+        return null;
+      }
+
+      final text = reader.readCString();
+
+      // Extract sender name and actual message from "name: msg" format
+      String senderName = 'Unknown';
+      String actualText = text;
+
+      final colonIndex = text.indexOf(':');
+      if (colonIndex > 0 && colonIndex < text.length - 1 && colonIndex < 50) {
+        final potentialSender = text.substring(0, colonIndex);
+        if (!RegExp(r'[:\[\]]').hasMatch(potentialSender)) {
+          senderName = potentialSender;
+          final offset =
+              (colonIndex + 1 < text.length && text[colonIndex + 1] == ' ')
+              ? colonIndex + 2
+              : colonIndex + 1;
+          actualText = text.substring(offset);
+        }
+      }
+
+      final decodedText = Smaz.tryDecodePrefixed(actualText) ?? actualText;
+
+      return ChannelMessage(
+        senderKey: null,
+        senderName: senderName,
+        text: decodedText,
+        timestamp: DateTime.fromMillisecondsSinceEpoch(timestampRaw * 1000),
+        isOutgoing: false,
+        status: ChannelMessageStatus.sent,
+        pathLength: pathLen,
+        pathBytes: pathBytes,
+        channelIndex: channelIdx,
+      );
+    } catch (e) {
+      appLogger.error('Error parsing channel message frame: $e');
+      // If parsing fails, return null to avoid crashes
       return null;
     }
-
-    int timestampOffset, textOffset, pathLenOffset, txtTypeOffset;
-    Uint8List pathBytes = Uint8List(0);
-    int channelIdx;
-
-    if (code == respCodeChannelMsgRecvV3) {
-      channelIdx = data[4];
-      pathLenOffset = 5;
-      final pathLen = data[pathLenOffset].toSigned(8);
-      var cursor = 6;
-      final hasPathBytesFlag = (data[2] & 0x01) != 0;
-      final canFitPath = pathLen > 0 && data.length >= cursor + pathLen + 5;
-      final hasValidTxtType =
-          cursor < data.length &&
-          (data[cursor] == txtTypePlain || data[cursor] == txtTypeCliData);
-      if ((hasPathBytesFlag || (canFitPath && !hasValidTxtType)) &&
-          canFitPath) {
-        pathBytes = Uint8List.fromList(data.sublist(cursor, cursor + pathLen));
-        cursor += pathLen;
-      }
-      txtTypeOffset = cursor;
-      cursor += 1; // txt_type
-      timestampOffset = cursor;
-      textOffset = cursor + 4;
-    } else {
-      channelIdx = data[1];
-      pathLenOffset = 2;
-      txtTypeOffset = 3;
-      timestampOffset = 4;
-      textOffset = 8;
-    }
-
-    if (data.length < textOffset + 1) return null;
-
-    final txtType = data[txtTypeOffset];
-    if (txtType != txtTypePlain) {
-      return null;
-    }
-
-    final pathLen = data[pathLenOffset].toSigned(8);
-    final timestampRaw = readUint32LE(data, timestampOffset);
-    final text = readCString(data, textOffset, data.length - textOffset);
-
-    // Extract sender name and actual message from "name: msg" format
-    String senderName = 'Unknown';
-    String actualText = text;
-
-    final colonIndex = text.indexOf(':');
-    if (colonIndex > 0 && colonIndex < text.length - 1 && colonIndex < 50) {
-      final potentialSender = text.substring(0, colonIndex);
-      if (!RegExp(r'[:\[\]]').hasMatch(potentialSender)) {
-        senderName = potentialSender;
-        final offset =
-            (colonIndex + 1 < text.length && text[colonIndex + 1] == ' ')
-            ? colonIndex + 2
-            : colonIndex + 1;
-        actualText = text.substring(offset);
-      }
-    }
-
-    final decodedText = Smaz.tryDecodePrefixed(actualText) ?? actualText;
-
-    return ChannelMessage(
-      senderKey: null,
-      senderName: senderName,
-      text: decodedText,
-      timestamp: DateTime.fromMillisecondsSinceEpoch(timestampRaw * 1000),
-      isOutgoing: false,
-      status: ChannelMessageStatus.sent,
-      pathLength: pathLen,
-      pathBytes: pathBytes,
-      channelIndex: channelIdx,
-    );
   }
 
   static ChannelMessage outgoing(

lib/models/contact.dart

@@ -18,6 +18,7 @@ class Contact {
   final DateTime lastSeen;
   final DateTime lastMessageAt;
   final bool isActive;
+  final bool wasPulled;
   final Uint8List? rawPacket;
 
   Contact({
@@ -34,6 +35,7 @@ class Contact {
     required this.lastSeen,
     DateTime? lastMessageAt,
     this.isActive = true,
+    this.wasPulled = false,
     this.rawPacket,
   }) : lastMessageAt = lastMessageAt ?? lastSeen;
 

lib/models/message.dart

@@ -16,7 +16,7 @@ class Message {
   final String? messageId;
   final int retryCount;
   final int? estimatedTimeoutMs;
-  final Uint8List? expectedAckHash;
+  final int? expectedAckHash;
   final DateTime? sentAt;
   final DateTime? deliveredAt;
   final int? tripTimeMs;
@@ -56,7 +56,7 @@ class Message {
     MessageStatus? status,
     int? retryCount,
     int? estimatedTimeoutMs,
-    Uint8List? expectedAckHash,
+    int? expectedAckHash,
     DateTime? sentAt,
     DateTime? deliveredAt,
     int? tripTimeMs,
@@ -90,33 +90,35 @@ class Message {
     );
   }
 
-  static Message? fromFrame(Uint8List data, Uint8List selfPubKey) {
+  static Message? fromFrame(Uint8List frame, Uint8List selfPubKey) {
-    if (data.length < msgTextOffset + 1) return null;
+    if (frame.length < msgTextOffset + 1) return null;
+    final reader = BufferReader(frame);
+    try {
+      final code = reader.readByte();
+      if (code != respCodeContactMsgRecv && code != respCodeContactMsgRecvV3) {
+        return null;
+      }
 
-    final code = data[0];
+      final senderKey = reader.readBytes(pubKeySize);
-    if (code != respCodeContactMsgRecv && code != respCodeContactMsgRecvV3) {
+      final timestampRaw = reader.readInt32LE();
+      final flags = reader.readByte();
+      if ((flags >> 2) != txtTypePlain) {
+        return null;
+      }
+      final text = reader.readCString();
+
+      return Message(
+        senderKey: senderKey,
+        text: text,
+        timestamp: DateTime.fromMillisecondsSinceEpoch(timestampRaw * 1000),
+        isOutgoing: false,
+        isCli: false,
+        status: MessageStatus.delivered,
+        pathBytes: Uint8List(0),
+      );
+    } catch (e) {
       return null;
     }
-
-    final senderKey = Uint8List.fromList(
-      data.sublist(msgPubKeyOffset, msgPubKeyOffset + pubKeySize),
-    );
-    final timestampRaw = readUint32LE(data, msgTimestampOffset);
-    final flags = data[msgFlagsOffset];
-    if ((flags >> 2) != txtTypePlain) {
-      return null;
-    }
-    final text = readCString(data, msgTextOffset, data.length - msgTextOffset);
-
-    return Message(
-      senderKey: senderKey,
-      text: text,
-      timestamp: DateTime.fromMillisecondsSinceEpoch(timestampRaw * 1000),
-      isOutgoing: false,
-      isCli: false,
-      status: MessageStatus.delivered,
-      pathBytes: Uint8List(0),
-    );
   }
 
   static Message outgoing(

lib/screens/ble_debug_log_screen.dart

@@ -283,66 +283,66 @@ class _BleDebugLogScreenState extends State<BleDebugLogScreen> {
     if (payload.length < 101) {
       return 'ADVERT (short)';
     }
-    var offset = 0;
+    final reader = BufferReader(payload);
-    final pubKey = _bytesToHex(
+    try {
-      payload.sublist(offset, offset + 32),
+      final pubKey = _bytesToHex(reader.readBytes(pubKeySize), spaced: false);
-      spaced: false,
+
-    );
+      final timestamp = reader.readUInt32LE();
-    offset += 32;
+      reader.skipBytes(signatureSize);
-    final timestamp = readUint32LE(payload, offset);
+      final flags = reader.readByte();
-    offset += 4;
+      final role = _deviceRoleLabel(flags & 0x0F);
-    offset += 64; // signature
+      final hasLocation = (flags & 0x10) != 0;
-    final flags = payload[offset++];
+      final hasFeature1 = (flags & 0x20) != 0;
-    final role = _deviceRoleLabel(flags & 0x0F);
+      final hasFeature2 = (flags & 0x40) != 0;
-    final hasLocation = (flags & 0x10) != 0;
+      final hasName = (flags & 0x80) != 0;
-    final hasFeature1 = (flags & 0x20) != 0;
+      String? name;
-    final hasFeature2 = (flags & 0x40) != 0;
+      double? lat;
-    final hasName = (flags & 0x80) != 0;
+      double? lon;
-    String? name;
+      if (hasLocation) {
-    double? lat;
+        lat = reader.readInt32LE() / 1000000.0;
-    double? lon;
+        lon = reader.readInt32LE() / 1000000.0;
-    if (hasLocation && payload.length >= offset + 8) {
+      }
-      lat = readInt32LE(payload, offset) / 1000000.0;
+      if (hasFeature1) reader.skipBytes(2);
-      lon = readInt32LE(payload, offset + 4) / 1000000.0;
+      if (hasFeature2) reader.skipBytes(2);
-      offset += 8;
+      if (hasName) {
+        name = reader.readCStringGreedy(maxNameSize);
+      }
+      final namePart = (name != null && name.isNotEmpty) ? ' name="$name"' : '';
+      final locPart = (lat != null && lon != null)
+          ? ' loc=${lat.toStringAsFixed(6)},${lon.toStringAsFixed(6)}'
+          : '';
+      return 'ADVERT role=$role ts=$timestamp$namePart$locPart key=${pubKey.substring(0, 12)}…';
+    } catch (e) {
+      return 'ADVERT (invalid)';
     }
-    if (hasFeature1) offset += 2;
-    if (hasFeature2) offset += 2;
-    if (hasName && payload.length > offset) {
-      final rawName = String.fromCharCodes(payload.sublist(offset));
-      final nul = rawName.indexOf('\u0000');
-      name = nul >= 0 ? rawName.substring(0, nul) : rawName;
-      name = name.trim();
-    }
-    final namePart = (name != null && name.isNotEmpty) ? ' name="$name"' : '';
-    final locPart = (lat != null && lon != null)
-        ? ' loc=${lat.toStringAsFixed(6)},${lon.toStringAsFixed(6)}'
-        : '';
-    return 'ADVERT role=$role ts=$timestamp$namePart$locPart key=${pubKey.substring(0, 12)}…';
   }
 
   String _decodeControlSummary(Uint8List payload) {
-    if (payload.isEmpty) return 'CONTROL (empty)';
+    final reader = BufferReader(payload);
-    final flags = payload[0];
+    try {
-    final subType = flags & 0xF0;
+      final flags = reader.readByte();
-    if (subType == 0x80) {
+      final subType = flags & 0xF0;
-      if (payload.length < 6) return 'CONTROL DISCOVER_REQ (short)';
+      if (subType == 0x80) {
-      final typeFilter = payload[1];
+        if (payload.length < 6) return 'CONTROL DISCOVER_REQ (short)';
-      final tag = readUint32LE(payload, 2);
+        final typeFilter = reader.readByte();
-      final since = payload.length >= 10 ? readUint32LE(payload, 6) : 0;
+        final tag = reader.readInt32LE();
-      return 'CONTROL DISCOVER_REQ filter=0x${typeFilter.toRadixString(16).padLeft(2, '0')} tag=$tag since=$since';
+        final since = payload.length >= 10 ? reader.readInt32LE() : 0;
+        return 'CONTROL DISCOVER_REQ filter=0x${typeFilter.toRadixString(16).padLeft(2, '0')} tag=$tag since=$since';
+      }
+      if (subType == 0x90) {
+        if (payload.length < 14) return 'CONTROL DISCOVER_RESP (short)';
+        final nodeType = flags & 0x0F;
+        final snrRaw = payload[1];
+        final snrSigned = snrRaw > 127 ? snrRaw - 256 : snrRaw;
+        final snr = snrSigned / 4.0;
+        final tag = reader.readInt32LE();
+        final keyLen = payload.length - 6;
+        return 'CONTROL DISCOVER_RESP node=${_deviceRoleLabel(nodeType)} snr=${snr.toStringAsFixed(2)} tag=$tag key=$keyLen';
+      }
+      return 'CONTROL subtype=0x${subType.toRadixString(16).padLeft(2, '0')}';
+    } catch (e) {
+      return 'CONTROL (invalid)';
     }
-    if (subType == 0x90) {
-      if (payload.length < 14) return 'CONTROL DISCOVER_RESP (short)';
-      final nodeType = flags & 0x0F;
-      final snrRaw = payload[1];
-      final snrSigned = snrRaw > 127 ? snrRaw - 256 : snrRaw;
-      final snr = snrSigned / 4.0;
-      final tag = readUint32LE(payload, 2);
-      final keyLen = payload.length - 6;
-      return 'CONTROL DISCOVER_RESP node=${_deviceRoleLabel(nodeType)} snr=${snr.toStringAsFixed(2)} tag=$tag key=$keyLen';
-    }
-    return 'CONTROL subtype=0x${subType.toRadixString(16).padLeft(2, '0')}';
   }
 
   String _payloadTypeLabel(int payloadType) {

lib/screens/channel_message_path_screen.dart

@@ -40,8 +40,7 @@ class ChannelMessagePathScreen extends StatelessWidget {
         final primaryPath = !channelMessage && !message.isOutgoing
             ? Uint8List.fromList(primaryPathTmp.reversed.toList())
             : primaryPathTmp;
-        final contacts = connector.allContacts;
+        final hops = _buildPathHops(primaryPath, connector, l10n);
-        final hops = _buildPathHops(primaryPath, contacts, l10n);
         final hasHopDetails = primaryPath.isNotEmpty;
         final observedLabel = _formatObservedHops(
           primaryPath.length,
@@ -303,10 +302,12 @@ class _ChannelMessagePathMapScreenState
     extends State<ChannelMessagePathMapScreen> {
   static const double _labelZoomThreshold = 8.5;
 
+  final MapController _mapController = MapController();
   Uint8List? _selectedPath;
   double _pathDistance = 0.0;
   bool _showNodeLabels = true;
   bool _didReceivePositionUpdate = false;
+  int? _focusedHopIndex;
 
   @override
   void initState() {
@@ -337,6 +338,22 @@ class _ChannelMessagePathMapScreenState
     return totalDistance;
   }
 
+  void _focusHop(_PathHop hop) {
+    if (!hop.hasLocation) return;
+    final targetZoom = _didReceivePositionUpdate
+        ? max(_mapController.camera.zoom, 10.0)
+        : 12.0;
+    _mapController.move(hop.position!, targetZoom);
+  }
+
+  void _onHopTapped(_PathHop hop) {
+    _focusHop(hop);
+    if (!mounted) return;
+    setState(() {
+      _focusedHopIndex = hop.index;
+    });
+  }
+
   @override
   Widget build(BuildContext context) {
     return Consumer<MeshCoreConnector>(
@@ -365,8 +382,7 @@ class _ChannelMessagePathMapScreenState
             : selectedPathTmp;
 
         final selectedIndex = _indexForPath(selectedPath, observedPaths);
-        final contacts = connector.allContacts;
+        final hops = _buildPathHops(selectedPath, connector, context.l10n);
-        final hops = _buildPathHops(selectedPath, contacts, context.l10n);
 
         final points = <LatLng>[];
 
@@ -421,6 +437,7 @@ class _ChannelMessagePathMapScreenState
               children: [
                 FlutterMap(
                   key: mapKey,
+                  mapController: _mapController,
                   options: MapOptions(
                     initialCenter: initialCenter,
                     initialZoom: initialZoom,
@@ -472,6 +489,7 @@ class _ChannelMessagePathMapScreenState
                   ) {
                     setState(() {
                       _selectedPath = observedPaths[index].pathBytes;
+                      _focusedHopIndex = null;
                     });
                   }),
                 if (points.isEmpty)
@@ -727,8 +745,17 @@ class _ChannelMessagePathMapScreenState
                         separatorBuilder: (_, _) => const Divider(height: 1),
                         itemBuilder: (context, index) {
                           final hop = hops[index];
+                          final isFocused = _focusedHopIndex == hop.index;
                           return ListTile(
                             dense: true,
+                            enabled: hop.hasLocation,
+                            selected: isFocused,
+                            selectedTileColor: Theme.of(
+                              context,
+                            ).colorScheme.primary.withValues(alpha: 0.12),
+                            onTap: hop.hasLocation
+                                ? () => _onHopTapped(hop)
+                                : null,
                             leading: CircleAvatar(
                               radius: 14,
                               child: Text(
@@ -787,19 +814,71 @@ class _ObservedPath {
 
 List<_PathHop> _buildPathHops(
   Uint8List pathBytes,
-  List<Contact> contacts,
+  MeshCoreConnector connector,
   AppLocalizations l10n,
 ) {
+  if (pathBytes.isEmpty) return const [];
+  final candidatesByPrefix = <int, List<Contact>>{};
+  for (final contact in connector.allContacts) {
+    if (contact.publicKey.isEmpty) continue;
+    if (contact.type != advTypeRepeater && contact.type != advTypeRoom) {
+      continue;
+    }
+    final prefix = contact.publicKey.first;
+    candidatesByPrefix.putIfAbsent(prefix, () => <Contact>[]).add(contact);
+  }
+  for (final candidates in candidatesByPrefix.values) {
+    candidates.sort((a, b) => b.lastSeen.compareTo(a.lastSeen));
+  }
+  final startPoint =
+      (connector.selfLatitude != null && connector.selfLongitude != null)
+      ? LatLng(connector.selfLatitude!, connector.selfLongitude!)
+      : null;
+  var previousPosition = startPoint;
+  final distance = Distance();
+
   final hops = <_PathHop>[];
   for (var i = 0; i < pathBytes.length; i++) {
-    final prefix = pathBytes[i];
+    final searchPoint = i == 0 ? startPoint : previousPosition;
-    final contact = _matchContactForPrefix(contacts, prefix);
+    final candidates = candidatesByPrefix[pathBytes[i]];
+    Contact? contact;
+    if (candidates != null && candidates.isNotEmpty) {
+      var bestIndex = 0;
+      if (searchPoint != null) {
+        var bestDistance = double.infinity;
+        for (var j = 0; j < candidates.length; j++) {
+          final candidate = candidates[j];
+          if (!candidate.hasLocation ||
+              candidate.latitude == null ||
+              candidate.longitude == null) {
+            continue;
+          }
+          final currentDistance = distance(
+            searchPoint,
+            LatLng(candidate.latitude!, candidate.longitude!),
+          );
+          if (currentDistance < bestDistance) {
+            bestDistance = currentDistance;
+            bestIndex = j;
+          }
+        }
+      }
+      contact = candidates.removeAt(bestIndex);
+      if (candidates.isEmpty) {
+        candidatesByPrefix.remove(pathBytes[i]);
+      }
+    }
+
+    final resolvedPosition = _resolvePosition(contact);
+    if (resolvedPosition != null) {
+      previousPosition = resolvedPosition;
+    }
     hops.add(
       _PathHop(
         index: i + 1,
-        prefix: prefix,
+        prefix: pathBytes[i],
         contact: contact,
-        position: _resolvePosition(contact),
+        position: resolvedPosition,
         l10n: l10n,
       ),
     );
@@ -807,42 +886,13 @@ List<_PathHop> _buildPathHops(
   return hops;
 }
 
-Contact? _matchContactForPrefix(List<Contact> contacts, int prefix) {
-  final matches = contacts
-      .where(
-        (contact) =>
-            (contact.type == advTypeRepeater || contact.type == advTypeRoom) &&
-            contact.publicKey.isNotEmpty &&
-            contact.publicKey[0] == prefix,
-      )
-      .toList();
-  if (matches.isEmpty) return null;
-
-  Contact? pickWhere(bool Function(Contact) predicate) {
-    for (final contact in matches) {
-      if (predicate(contact)) return contact;
-    }
-    return null;
-  }
-
-  return pickWhere((c) => c.type == advTypeRepeater && _hasValidLocation(c)) ??
-      pickWhere((c) => c.type == advTypeRepeater) ??
-      pickWhere(_hasValidLocation) ??
-      matches.first;
-}
-
 LatLng? _resolvePosition(Contact? contact) {
   if (contact == null) return null;
-  if (!_hasValidLocation(contact)) return null;
+  if (!contact.hasLocation) return null;
-  return LatLng(contact.latitude!, contact.longitude!);
+  final latitude = contact.latitude;
-}
+  final longitude = contact.longitude;
-
+  if (latitude == null || longitude == null) return null;
-bool _hasValidLocation(Contact contact) {
+  return LatLng(latitude, longitude);
-  final lat = contact.latitude;
-  final lon = contact.longitude;
-  if (lat == null || lon == null) return false;
-  if (lat == 0 && lon == 0) return false;
-  return true;
 }
 
 String _formatPrefix(int prefix) {

lib/screens/settings_screen.dart

@@ -970,7 +970,6 @@ void _privacySettings(BuildContext context, MeshCoreConnector connector) {
                 value: advertLocPolicy,
                 onChanged: (value) {
                   setDialogState(() => advertLocPolicy = value);
-                  advertLocPolicy = value;
                 },
               ),
               const SizedBox(height: 8),

lib/services/message_retry_service.dart

@@ -11,7 +11,7 @@ import 'app_debug_log_service.dart';
 
 class _AckHistoryEntry {
   final String messageId;
-  final List<Uint8List> ackHashes;
+  final List<int> ackHashes;
   final DateTime timestamp;
 
   _AckHistoryEntry({
@@ -77,7 +77,7 @@ class MessageRetryService extends ChangeNotifier {
   final Map<String, Contact> _pendingContacts = {};
   final Map<String, List<PathSelection>> _attemptPathHistory = {};
   final Map<String, AckHashMapping> _ackHashToMessageId = {};
-  final Map<String, List<Uint8List>> _expectedAckHashes = {};
+  final Map<String, List<int>> _expectedAckHashes = {};
   final List<_AckHistoryEntry> _ackHistory = [];
   final Map<String, List<String>> _sendQueue = {};
   final Set<String> _activeMessages = {};
@@ -98,7 +98,7 @@ class MessageRetryService extends ChangeNotifier {
 
   /// Compute expected ACK hash using same algorithm as firmware:
   /// SHA256([timestamp(4)][attempt(1)][text][sender_pubkey(32)]) -> first 4 bytes
-  static Uint8List computeExpectedAckHash(
+  static int computeExpectedAckHash(
     int timestampSeconds,
     int attempt,
     String text,
@@ -126,7 +126,8 @@ class MessageRetryService extends ChangeNotifier {
 
     // Compute SHA256 and return first 4 bytes
     final hash = sha256.convert(buffer);
-    return Uint8List.fromList(hash.bytes.sublist(0, 4));
+    final bytes = Uint8List.fromList(hash.bytes.sublist(0, 4));
+    return (bytes[3] << 24) | (bytes[2] << 16) | (bytes[1] << 8) | bytes[0];
   }
 
   Future<void> sendMessageWithRetry({
@@ -324,9 +325,7 @@ class MessageRetryService extends ChangeNotifier {
         outboundText,
         selfPubKey,
       );
-      final expectedHashHex = expectedHash
+      final expectedHashHex = expectedHash.toRadixString(16).padLeft(8, '0');
-          .map((b) => b.toRadixString(16).padLeft(2, '0'))
-          .join();
       _expectedHashToMessageId[expectedHashHex] = messageId;
 
       final shortText = message.text.length > 20
@@ -341,13 +340,11 @@ class MessageRetryService extends ChangeNotifier {
     config.sendMessage(contact, message.text, attempt, timestampSeconds);
   }
 
-  bool updateMessageFromSent(Uint8List ackHash, int timeoutMs) {
+  bool updateMessageFromSent(int ackHash, int timeoutMs) {
     final config = _config;
     if (config == null) return false;
 
-    final ackHashHex = ackHash
+    final ackHashHex = ackHash.toRadixString(16).padLeft(8, '0');
-        .map((b) => b.toRadixString(16).padLeft(2, '0'))
-        .join();
 
     // Try hash-based matching (fixes LoRa message drops causing mismatches)
     String? messageId = _expectedHashToMessageId.remove(ackHashHex);
@@ -389,10 +386,8 @@ class MessageRetryService extends ChangeNotifier {
 
     // Add this ACK hash to the list of expected ACKs for this message (for history)
     _expectedAckHashes[messageId] ??= [];
-    if (!_expectedAckHashes[messageId]!.any(
+    if (!_expectedAckHashes[messageId]!.any((hash) => hash == ackHash)) {
-      (hash) => listEquals(hash, ackHash),
+      _expectedAckHashes[messageId]!.add(ackHash);
-    )) {
-      _expectedAckHashes[messageId]!.add(Uint8List.fromList(ackHash));
     }
 
     // Calculate timeout: prefer ML prediction, then device-provided, then physics fallback
@@ -559,10 +554,10 @@ class MessageRetryService extends ChangeNotifier {
     }
   }
 
-  bool _checkAckHistory(Uint8List ackHash) {
+  bool _checkAckHistory(int ackHash) {
     for (final entry in _ackHistory) {
       for (final expectedHash in entry.ackHashes) {
-        if (listEquals(expectedHash, ackHash)) {
+        if (expectedHash == ackHash) {
           return true;
         }
       }
@@ -570,13 +565,11 @@ class MessageRetryService extends ChangeNotifier {
     return false;
   }
 
-  void handleAckReceived(Uint8List ackHash, int tripTimeMs) {
+  void handleAckReceived(int ackHash, int tripTimeMs) {
     final config = _config;
     String? matchedMessageId;
     int? matchedAttemptIndex;
-    final ackHashHex = ackHash
+    final ackHashHex = ackHash.toRadixString(16).padLeft(8, '0');
-        .map((b) => b.toRadixString(16).padLeft(2, '0'))
-        .join();
 
     // Clean up old ACK hash mappings (older than 15 minutes)
     final cutoffTime = DateTime.now().subtract(const Duration(minutes: 15));
@@ -606,7 +599,7 @@ class MessageRetryService extends ChangeNotifier {
         final expectedHashes = entry.value;
 
         for (final expectedHash in expectedHashes) {
-          if (listEquals(expectedHash, ackHash)) {
+          if (expectedHash == ackHash) {
             matchedMessageId = messageId;
             matchedAttemptIndex = expectedHashes.indexOf(expectedHash);
             break;
@@ -685,11 +678,11 @@ class MessageRetryService extends ChangeNotifier {
     }
   }
 
-  String? getContactKeyForAckHash(Uint8List ackHash) {
+  String? getContactKeyForAckHash(int ackHash) {
     for (var entry in _pendingMessages.entries) {
       final message = entry.value;
       if (message.expectedAckHash != null &&
-          listEquals(message.expectedAckHash, ackHash)) {
+          message.expectedAckHash == ackHash) {
         final contact = _pendingContacts[entry.key];
         return contact?.publicKeyHex;
       }

lib/storage/message_store.dart

@@ -85,9 +85,7 @@ class MessageStore {
       'messageId': msg.messageId,
       'retryCount': msg.retryCount,
       'estimatedTimeoutMs': msg.estimatedTimeoutMs,
-      'expectedAckHash': msg.expectedAckHash != null
+      'expectedAckHash': msg.expectedAckHash,
-          ? base64Encode(msg.expectedAckHash!)
-          : null,
       'sentAt': msg.sentAt?.millisecondsSinceEpoch,
       'deliveredAt': msg.deliveredAt?.millisecondsSinceEpoch,
       'tripTimeMs': msg.tripTimeMs,
@@ -119,9 +117,7 @@ class MessageStore {
       messageId: json['messageId'] as String?,
       retryCount: json['retryCount'] as int? ?? 0,
       estimatedTimeoutMs: json['estimatedTimeoutMs'] as int?,
-      expectedAckHash: json['expectedAckHash'] != null
+      expectedAckHash: json['expectedAckHash'] as int? ?? 0,
-          ? Uint8List.fromList(base64Decode(json['expectedAckHash'] as String))
-          : null,
       sentAt: json['sentAt'] != null
           ? DateTime.fromMillisecondsSinceEpoch(json['sentAt'] as int)
           : null,

macos/Flutter/GeneratedPluginRegistrant.swift

@@ -9,6 +9,7 @@ import flutter_blue_plus_darwin
 import flutter_local_notifications
 import mobile_scanner
 import package_info_plus
+import path_provider_foundation
 import share_plus
 import shared_preferences_foundation
 import sqflite_darwin
@@ -20,6 +21,7 @@ func RegisterGeneratedPlugins(registry: FlutterPluginRegistry) {
   FlutterLocalNotificationsPlugin.register(with: registry.registrar(forPlugin: "FlutterLocalNotificationsPlugin"))
   MobileScannerPlugin.register(with: registry.registrar(forPlugin: "MobileScannerPlugin"))
   FPPPackageInfoPlusPlugin.register(with: registry.registrar(forPlugin: "FPPPackageInfoPlusPlugin"))
+  PathProviderPlugin.register(with: registry.registrar(forPlugin: "PathProviderPlugin"))
   SharePlusMacosPlugin.register(with: registry.registrar(forPlugin: "SharePlusMacosPlugin"))
   SharedPreferencesPlugin.register(with: registry.registrar(forPlugin: "SharedPreferencesPlugin"))
   SqflitePlugin.register(with: registry.registrar(forPlugin: "SqflitePlugin"))

test/services/retry_and_protocol_test.dart

@@ -14,7 +14,7 @@ import 'package:meshcore_open/services/message_retry_service.dart';
 
 /// Replicates the SHA-256 computation from [MessageRetryService.computeExpectedAckHash]
 /// so tests can cross-check without calling the real implementation twice.
-Uint8List _manualAckHash(
+int _manualAckHash(
   int timestampSeconds,
   int attemptMasked, // already masked to 0x03
   String text,
@@ -35,7 +35,8 @@ Uint8List _manualAckHash(
   buffer.setRange(offset, offset + senderPubKey.length, senderPubKey);
 
   final hash = sha256.convert(buffer);
-  return Uint8List.fromList(hash.bytes.sublist(0, 4));
+  final bytes = Uint8List.fromList(hash.bytes.sublist(0, 4));
+  return (bytes[3] << 24) | (bytes[2] << 16) | (bytes[1] << 8) | bytes[0];
 }
 
 Uint8List _makeKey(int seed) {
@@ -169,16 +170,6 @@ void main() {
       expect(first, equals(second));
     });
 
-    test('hash is exactly 4 bytes long', () {
-      final hash = MessageRetryService.computeExpectedAckHash(
-        fixedTs,
-        0,
-        fixedText,
-        fixedKey,
-      );
-      expect(hash.length, equals(4));
-    });
-
     test('hash matches manual SHA-256 computation', () {
       for (int attempt = 0; attempt < 4; attempt++) {
         final actual = MessageRetryService.computeExpectedAckHash(
@@ -509,7 +500,7 @@ void main() {
           fixedText,
           fixedKey,
         );
-        final hex = hash.map((b) => b.toRadixString(16).padLeft(2, '0')).join();
+        final hex = hash.toRadixString(16).padLeft(8, '0');
         expect(
           hashes.containsKey(hex),
           isFalse,