feat: add contact UI helpers and path editor for routing management

- Implemented contactTypeIcon and contactTypeColor functions for better UI representation of contact types.
- Created colorForName and firstCharacterOrEmoji functions to enhance contact display.
- Developed PathEditorSheet widget for managing contact paths with a user-friendly interface.
- Introduced RoutingSheet for managing contact routing modes and displaying path history.
- Added a script for generating proof of concept (PoC) payloads for clipboard contact import validation.

lib/connector/meshcore_connector.dart

@@ -160,6 +160,7 @@ class MeshCoreConnector extends ChangeNotifier {
       {}; // contactPubKeyHex -> Set of "targetHash_emoji"
 
   StreamSubscription<List<ScanResult>>? _scanSubscription;
+  StreamSubscription<bool>? _isScanningSubscription;
   StreamSubscription<BluetoothConnectionState>? _connectionSubscription;
   StreamSubscription<List<int>>? _notifySubscription;
   Timer? _notifyListenersTimer;
@@ -507,10 +508,22 @@ class MeshCoreConnector extends ChangeNotifier {
     if (messages == null) return;
     final removed = messages.remove(message);
     if (!removed) return;
+    _retryService?.untrack(message.messageId);
     await _messageStore.saveMessages(contactKeyHex, messages);
     notifyListeners();
   }
 
+  Future<void> resendMessage(Contact contact, Message message) async {
+    await deleteMessage(message);
+    await sendMessage(
+      contact,
+      message.text,
+      originalText: message.originalText,
+      translatedLanguageCode: message.translatedLanguageCode,
+      translationModelId: message.translationModelId,
+    );
+  }
+
   Future<void> _loadMessagesForContact(String contactKeyHex) async {
     if (_loadedConversationKeys.contains(contactKeyHex)) return;
     _loadedConversationKeys.add(contactKeyHex);
@@ -1356,6 +1369,21 @@ class MeshCoreConnector extends ChangeNotifier {
   }) async {
     if (_state == MeshCoreConnectionState.scanning) return;
 
+    // A BLE scan must never disturb an active (or in-progress) non-BLE
+    // connection. The connection state enum is shared across transports, so
+    // entering the `scanning` state while connected over TCP/USB would clobber
+    // the live `connected` state and later reset it to `disconnected`.
+    if (_state != MeshCoreConnectionState.disconnected ||
+        _tcpConnector.isConnected ||
+        _usbManager.isConnected) {
+      _appDebugLogService?.warn(
+        'startScan ignored: not idle (state=$_state, '
+        'tcp=${_tcpConnector.isConnected}, usb=${_usbManager.isConnected})',
+        tag: 'BLE Scan',
+      );
+      return;
+    }
+
     _scanResults.clear();
     _linuxSystemScanResults.clear();
     _setState(MeshCoreConnectionState.scanning);
@@ -1409,20 +1437,40 @@ class MeshCoreConnector extends ChangeNotifier {
     });
 
     try {
+      // Filter by the Nordic UART Service UUID rather than by advertised
+      // name. All MeshCore-compatible firmware (ESP32 + nRF52) advertises this
+      // service UUID, so this matches every device regardless of the name it
+      // chooses to advertise (e.g. community forks like the M5 Cardputer that
+      // do not use a "MeshCore-" name prefix). This mirrors how the official
+      // app discovers devices. Note: on Android `withKeywords` cannot be
+      // combined with any other filter, which is why name keywords are not
+      // used here.
       await FlutterBluePlus.startScan(
-        withKeywords: MeshCoreUuids.deviceNamePrefixes,
+        withServices: [Guid(MeshCoreUuids.service)],
         webOptionalServices: [Guid(MeshCoreUuids.service)],
         timeout: timeout,
         androidScanMode: AndroidScanMode.lowLatency,
       );
     } catch (error) {
       _appDebugLogService?.warn('Scan/picker failure: $error', tag: 'BLE Scan');
-      _setState(MeshCoreConnectionState.disconnected);
+      await stopScan();
       rethrow;
     }
 
-    await Future.delayed(timeout);
-    await stopScan();
+    // Reset our shared state when the native scan ends — whether it was stopped
+    // by the user (stopScan), by the platform timeout, or by Bluetooth turning
+    // off. This replaces a blocking `Future.delayed(timeout)` tail that kept
+    // startScan() pending for the whole timeout and made Stop appear ineffective.
+    // `isScanning` is a re-emit stream that replays its latest value on listen,
+    // so skip(1) to ignore that and only react to a genuine transition to false.
+    await _isScanningSubscription?.cancel();
+    _isScanningSubscription = FlutterBluePlus.isScanning.skip(1).listen((
+      scanning,
+    ) {
+      if (!scanning && _state == MeshCoreConnectionState.scanning) {
+        unawaited(stopScan());
+      }
+    });
   }
 
   Future<void> _loadLinuxSystemDevicesForScan() async {
@@ -1430,15 +1478,13 @@ class MeshCoreConnector extends ChangeNotifier {
       final systemDevices = await FlutterBluePlus.systemDevices([
         Guid(MeshCoreUuids.service),
       ]);
+      // systemDevices is already filtered by the NUS service UUID above, so no
+      // additional name-prefix filtering is applied here. This keeps Linux
+      // discovery name-agnostic and consistent with the main scan path.
       _linuxSystemScanResults
         ..clear()
         ..addAll(
           systemDevices
-              .where(
-                (device) => MeshCoreUuids.deviceNamePrefixes.any(
-                  device.platformName.startsWith,
-                ),
-              )
               .map(
                 (device) => ScanResult(
                   device: device,
@@ -1499,9 +1545,17 @@ class MeshCoreConnector extends ChangeNotifier {
     }
     await _scanSubscription?.cancel();
     _scanSubscription = null;
+    await _isScanningSubscription?.cancel();
+    _isScanningSubscription = null;
 
     if (_state == MeshCoreConnectionState.scanning) {
-      _setState(MeshCoreConnectionState.disconnected);
+      // Restore to `connected` if a non-BLE transport is still live, so a stray
+      // scan can never tear down the reported connection state. Normally there
+      // is no live transport here and we fall through to `disconnected`.
+      final restored = (_tcpConnector.isConnected || _usbManager.isConnected)
+          ? MeshCoreConnectionState.connected
+          : MeshCoreConnectionState.disconnected;
+      _setState(restored);
     }
   }
 
@@ -1743,6 +1797,17 @@ class MeshCoreConnector extends ChangeNotifier {
         activeTransport == MeshCoreTransportType.tcp;
   }
 
+  /// Fast (non-timeout) connect failures are usually a stale link left over
+  /// from a previous session and recover on an immediate retry. Timeouts mean
+  /// the device is likely off or out of range, so retrying would only delay
+  /// genuine failure feedback.
+  @visibleForTesting
+  static bool shouldRetryBleConnectAfterError(String errorText) {
+    final lowerErrorText = errorText.toLowerCase();
+    return !lowerErrorText.contains('timed out') &&
+        !lowerErrorText.contains('timeout');
+  }
+
   Future<void> connect(
     BluetoothDevice device, {
     String? displayName,
@@ -1911,18 +1976,71 @@ class MeshCoreConnector extends ChangeNotifier {
           }
         }
       } else {
-        try {
-          await device.connect(
+        Future<void> attemptConnect() {
+          return device.connect(
             timeout: connectTimeout,
             mtu: null,
             license: License.free,
           );
+        }
+
+        // A previous app session (e.g. killed from the iOS app switcher) can
+        // leave the OS holding a stale link to the peripheral. Clear it before
+        // connecting so the fresh attempt doesn't race the stale handle.
+        if (!PlatformInfo.isWeb && device.isConnected) {
+          _appDebugLogService?.warn(
+            'Device reports an existing connection before connect; clearing stale link',
+            tag: 'BLE Connect',
+          );
+          try {
+            await device.disconnect(queue: false);
+          } catch (cleanupError) {
+            _appDebugLogService?.warn(
+              'Stale-link cleanup disconnect failed (continuing): $cleanupError',
+              tag: 'BLE Connect',
+            );
+          }
+        }
+
+        try {
+          await attemptConnect();
         } catch (error) {
           _appDebugLogService?.error(
             'device.connect() failure: $error',
             tag: 'BLE Connect',
           );
-          rethrow;
+          if (PlatformInfo.isWeb ||
+              !shouldRetryBleConnectAfterError(error.toString())) {
+            rethrow;
+          }
+          // Fast (non-timeout) failures are usually a stale connection left by
+          // a previous session; clean up and retry once before surfacing.
+          _appDebugLogService?.warn(
+            'Retrying connect once after clearing possible stale connection',
+            tag: 'BLE Connect',
+          );
+          try {
+            await device.disconnect(queue: false);
+          } catch (cleanupError) {
+            _appDebugLogService?.warn(
+              'Pre-retry cleanup disconnect failed (continuing): $cleanupError',
+              tag: 'BLE Connect',
+            );
+          }
+          await Future<void>.delayed(const Duration(milliseconds: 500));
+          try {
+            await attemptConnect();
+            _appDebugLogService?.info(
+              'Retry connect succeeded after stale-connection cleanup',
+              tag: 'BLE Connect',
+            );
+          } catch (retryError) {
+            _appDebugLogService?.error(
+              'device.connect() retry failure: $retryError',
+              tag: 'BLE Connect',
+            );
+            rethrow;
+          }
         }
       }
 
@@ -3237,6 +3355,7 @@ class MeshCoreConnector extends ChangeNotifier {
     await sendFrame(buildRemoveContactFrame(contact.publicKey));
     _contacts.removeWhere((c) => c.publicKeyHex == contact.publicKeyHex);
     _knownContactKeys.remove(contact.publicKeyHex);
+    unawaited(updateKnownDiscovered());
     unawaited(_persistContacts());
     _conversations.remove(contact.publicKeyHex);
     _loadedConversationKeys.remove(contact.publicKeyHex);
@@ -3450,12 +3569,10 @@ class MeshCoreConnector extends ChangeNotifier {
 
   Future<void> sendCliCommand(String command) async {
     if (!isConnected) return;
-
-    // CLI commands are sent as UTF-8 text with a special prefix
-    final commandBytes = utf8.encode(command);
-    final bytes = Uint8List.fromList([0x01, ...commandBytes, 0x00]);
+    final selfKey = _selfPublicKey;
+    if (selfKey == null) return;
     _lastSentWasCliCommand = true;
-    await sendFrame(bytes);
+    await sendFrame(buildSendCliCommandFrame(selfKey, command));
   }
 
   Future<void> setNodeName(String name) async {
@@ -3929,8 +4046,8 @@ class MeshCoreConnector extends ChangeNotifier {
       _advertLocPolicy = reader.readByte();
       final telemetryFlag = reader.readByte();
       _telemetryModeBase = telemetryFlag & 0x03;
-      _telemetryModeEnv = telemetryFlag >> 2 & 0x03;
-      _telemetryModeLoc = telemetryFlag >> 4 & 0x03;
+      _telemetryModeLoc = telemetryFlag >> 2 & 0x03;
+      _telemetryModeEnv = telemetryFlag >> 4 & 0x03;
 
       _manualAddContacts = reader.readByte() & 0x01 == 0x00;
 
@@ -4275,7 +4392,14 @@ class MeshCoreConnector extends ChangeNotifier {
           tag: 'Connector',
         );
         notifyListeners();
-        removeContact(contactTmp);
+        unawaited(
+          removeContact(contactTmp).catchError(
+            (e) => appLogger.warn(
+              'Failed to remove self contact: $e',
+              tag: 'Connector',
+            ),
+          ),
+        );
         return;
       }
       final contact = getFromDiscovered(contactTmp);
@@ -5521,6 +5645,9 @@ class MeshCoreConnector extends ChangeNotifier {
     }
 
     messages.add(message);
+    if (messages.length > _messageWindowSize) {
+      messages.removeRange(0, messages.length - _messageWindowSize);
+    }
     _messageStore.saveMessages(pubKeyHex, messages);
     notifyListeners();
   }
@@ -5907,20 +6034,24 @@ class MeshCoreConnector extends ChangeNotifier {
   bool _isChannelRepeat(ChannelMessage existing, ChannelMessage incoming) {
     if (existing.text != incoming.text) return false;
 
+    // Self-echo: an outgoing message coming back via a repeater. The send is
+    // delayed by _waitForRadioQuiet (often 10s+) and propagation can add more,
+    // so the timestamp gap can easily exceed the cross-peer window.
+    final selfName = _selfName ?? 'Me';
+    final isSelfEcho =
+        existing.isOutgoing &&
+        !incoming.isOutgoing &&
+        (incoming.senderName == selfName || existing.senderName == selfName);
+
+    final windowMs = isSelfEcho ? 10 * 60 * 1000 : 30000;
     final diffMs =
         (existing.timestamp.millisecondsSinceEpoch -
                 incoming.timestamp.millisecondsSinceEpoch)
             .abs();
-    if (diffMs > 30000) return false;
+    if (diffMs > windowMs) return false;
 
     if (existing.senderName == incoming.senderName) return true;
-
-    if (existing.isOutgoing && !incoming.isOutgoing) {
-      final selfName = _selfName ?? 'Me';
-      if (incoming.senderName == selfName || existing.senderName == selfName) {
-        return true;
-      }
-    }
+    if (isSelfEcho) return true;
 
     return false;
   }
@@ -6152,6 +6283,7 @@ class MeshCoreConnector extends ChangeNotifier {
   @override
   void dispose() {
     _scanSubscription?.cancel();
+    _isScanningSubscription?.cancel();
     _connectionSubscription?.cancel();
     _usbFrameSubscription?.cancel();
     _notifySubscription?.cancel();
@@ -6210,82 +6342,6 @@ class MeshCoreConnector extends ChangeNotifier {
     }
   }
 
-  void importContact(Uint8List frame) {
-    final packet = BufferReader(frame);
-    int payloadType = 0;
-    Uint8List pathBytes = Uint8List(0);
-    try {
-      packet.skipBytes(1); // Skip frame type byte
-      packet.skipBytes(1); // Skip SNR byte
-      packet.skipBytes(1); // Skip RSSI byte
-      final header = packet.readByte();
-      final routeType = header & 0x03;
-      payloadType = (header >> 2) & 0x0F;
-      if (routeType == _routeTransportFlood ||
-          routeType == _routeTransportDirect) {
-        packet.skipBytes(4); // Skip transport-specific bytes
-      }
-      //final payloadVer = (header >> 6) & 0x03;
-      final pathLenRaw = packet.readByte();
-      final pathByteLen = _decodePathByteLen(pathLenRaw);
-      pathBytes = packet.readBytes(pathByteLen);
-    } catch (e) {
-      appLogger.warn('Malformed RX frame: $e', tag: 'Connector');
-      return;
-    }
-    double? latitude;
-    double? longitude;
-    String name = '';
-    Uint8List publicKey = Uint8List(0);
-    int type = 0;
-    int timestamp = 0;
-    bool hasLocation = false;
-    bool hasName = false;
-    if (payloadType != payloadTypeADVERT) {
-      appLogger.warn('Unexpected payload type: $payloadType', tag: 'Connector');
-      return;
-    }
-    try {
-      publicKey = packet.readBytes(32);
-      timestamp = packet.readInt32LE();
-      //TODO add signature verification
-      packet.skipBytes(64); // Skip signature for now
-      final flags = packet.readByte();
-      type = flags & 0x0F;
-      hasLocation = (flags & 0x10) != 0;
-      // For future use:
-      //final hasFeature1 = (flags & 0x20) != 0;
-      //final hasFeature2 = (flags & 0x40) != 0;
-      hasName = (flags & 0x80) != 0;
-      if (hasLocation && packet.remaining >= 8) {
-        latitude = packet.readInt32LE() / 1e6;
-        longitude = packet.readInt32LE() / 1e6;
-      }
-      if (hasName && packet.remaining > 0) {
-        name = packet.readCString();
-      }
-    } catch (e) {
-      appLogger.warn('Malformed advert frame: $e', tag: 'Connector');
-      return;
-    }
-
-    importDiscoveredContact(
-      Contact(
-        rawPacket: frame,
-        publicKey: publicKey,
-        name: name,
-        type: type,
-        pathLength: pathBytes.isEmpty ? -1 : pathBytes.length,
-        path: Uint8List.fromList(
-          pathBytes.reversed.toList(),
-        ), // Store path in reverse for easier use in outgoing messages
-        latitude: latitude,
-        longitude: longitude,
-        lastSeen: DateTime.fromMillisecondsSinceEpoch(timestamp * 1000),
-      ),
-    );
-  }
-
   bool hasValidLocation(double? latitude, double? longitude) {
     const double epsilon = 1e-6;
     final lat = latitude ?? 0.0;

lib/connector/meshcore_protocol.dart

@@ -457,8 +457,13 @@ String pubKeyToHex(Uint8List pubKey) {
 
 // Helper to convert hex string to public key
 Uint8List hexToPubKey(String hex) {
+  if (hex.length != pubKeySize * 2) {
+    throw FormatException(
+      'Public key hex must be ${pubKeySize * 2} chars, got ${hex.length}',
+    );
+  }
   final result = Uint8List(pubKeySize);
-  for (int i = 0; i < pubKeySize && i * 2 + 1 < hex.length; i++) {
+  for (int i = 0; i < pubKeySize; i++) {
     result[i] = int.parse(hex.substring(i * 2, i * 2 + 2), radix: 16);
   }
   return result;

lib/connector/meshcore_uuids.dart

@@ -3,6 +3,10 @@ class MeshCoreUuids {
   static const String rxCharacteristic = "6e400002-b5a3-f393-e0a9-e50e24dcca9e";
   static const String txCharacteristic = "6e400003-b5a3-f393-e0a9-e50e24dcca9e";
 
+  /// Known advertised-name prefixes used by stock MeshCore firmware builds.
+  /// Discovery no longer filters on these (it filters on the [service] UUID so
+  /// that community forks with custom names are still found); kept for
+  /// reference and possible future display heuristics.
   static const List<String> deviceNamePrefixes = [
     "MeshCore-",
     "Whisper-",