Enhance location handling and UI updates

- Refactor location permission handling in SparseLocationLogger
- Add updateMyLocation method to SparseLocationLogger
- Introduce new contact handling in MeshCoreConnector
- Update map screen with a new option to refresh location
- Add localization for "Update Location" in app_en.arb
- Adjust payload types in meshcore_protocol.dart

lib/connector/meshcore_connector.dart

@@ -2,6 +2,8 @@ import 'dart:async';
 import 'dart:convert';
 
 import 'package:crypto/crypto.dart' as crypto;
+import 'package:geolocator/geolocator.dart';
+import 'package:meshcore_open/services/sparse_location_logger.dart';
 import 'package:pointycastle/export.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter_blue_plus/flutter_blue_plus.dart';
@@ -130,6 +132,7 @@ class MeshCoreConnector extends ChangeNotifier {
   PathHistoryService? _pathHistoryService;
   AppSettingsService? _appSettingsService;
   BackgroundService? _backgroundService;
+  SparseLocationLogger? _sparseLocationLogger;
   final NotificationService _notificationService = NotificationService();
   BleDebugLogService? _bleDebugLogService;
   AppDebugLogService? _appDebugLogService;
@@ -502,6 +505,7 @@ class MeshCoreConnector extends ChangeNotifier {
     BleDebugLogService? bleDebugLogService,
     AppDebugLogService? appDebugLogService,
     BackgroundService? backgroundService,
+    SparseLocationLogger? sparseLocationLogger,
   }) {
     _retryService = retryService;
     _pathHistoryService = pathHistoryService;
@@ -509,11 +513,14 @@ class MeshCoreConnector extends ChangeNotifier {
     _bleDebugLogService = bleDebugLogService;
     _appDebugLogService = appDebugLogService;
     _backgroundService = backgroundService;
+    _sparseLocationLogger = sparseLocationLogger;
 
     // Initialize notification service
     _notificationService.initialize();
     _loadChannelOrder();
 
+    _sparseLocationLogger?.initialize(_updateLocationandAdvert);
+
     // Initialize retry service callbacks
     _retryService?.initialize(
       sendMessageCallback: _sendMessageDirect,
@@ -828,6 +835,8 @@ class MeshCoreConnector extends ChangeNotifier {
     return result;
   }
 
+  SparseLocationLogger? get sparseLocationLogger => _sparseLocationLogger;
+
   bool get _shouldAutoReconnect => !_manualDisconnect && _lastDeviceId != null;
 
   void _cancelReconnectTimer() {
@@ -1690,6 +1699,11 @@ class MeshCoreConnector extends ChangeNotifier {
         _isLoadingContacts = true;
         notifyListeners();
         break;
+      case pushCodeNewAdvert:
+        debugPrint('Got New CONTACT');
+        // It the same format as respCodeContact, so we can reuse the handler
+        _handleContact(frame);
+        break;
       case respCodeContact:
         debugPrint('Got CONTACT');
         _handleContact(frame);
@@ -1734,6 +1748,7 @@ class MeshCoreConnector extends ChangeNotifier {
       case pushCodeStatusResponse:
         break;
       case pushCodeLogRxData:
+        _handleRxData(frame);
         _handleLogRxData(frame);
         break;
       case respCodeChannelInfo:
@@ -1747,6 +1762,7 @@ class MeshCoreConnector extends ChangeNotifier {
         break;
       case respCodeCustomVars:
         _handleCustomVars(frame);
+        break;
       default:
         debugPrint('Unknown frame code: $code');
     }
@@ -2002,6 +2018,76 @@ class MeshCoreConnector extends ChangeNotifier {
     }
   }
 
+  void _handleContactAdvert(Contact contact) {
+    if (contact.type == advTypeRepeater) {
+      _contactUnreadCount.remove(contact.publicKeyHex);
+      _unreadStore.saveContactUnreadCount(
+        Map<String, int>.from(_contactUnreadCount),
+      );
+    }
+    // Check if this is a new contact
+    final isNewContact = !_knownContactKeys.contains(contact.publicKeyHex);
+    final existingIndex = _contacts.indexWhere(
+      (c) => c.publicKeyHex == contact.publicKeyHex,
+    );
+
+    if (existingIndex >= 0) {
+      final existing = _contacts[existingIndex];
+      final mergedLastMessageAt =
+          existing.lastMessageAt.isAfter(contact.lastMessageAt)
+          ? existing.lastMessageAt
+          : contact.lastMessageAt;
+
+      appLogger.info(
+        'Refreshing contact ${contact.name}: devicePath=${contact.pathLength}, existingOverride=${existing.pathOverride}',
+        tag: 'Connector',
+      );
+
+      // CRITICAL: Preserve user's path override when contact is refreshed from device
+      _contacts[existingIndex] = contact.copyWith(
+        lastMessageAt: mergedLastMessageAt,
+        pathOverride: existing.pathOverride, // Preserve user's path choice
+        pathOverrideBytes: existing.pathOverrideBytes,
+      );
+
+      appLogger.info(
+        'After merge: pathOverride=${_contacts[existingIndex].pathOverride}, devicePath=${_contacts[existingIndex].pathLength}',
+        tag: 'Connector',
+      );
+    } else {
+      _contacts.add(contact);
+      appLogger.info(
+        'Added new contact ${contact.name}: pathLen=${contact.pathLength}',
+        tag: 'Connector',
+      );
+    }
+    _knownContactKeys.add(contact.publicKeyHex);
+    _loadMessagesForContact(contact.publicKeyHex);
+
+    // Add path to history if we have a valid path
+    if (_pathHistoryService != null && contact.pathLength >= 0) {
+      _pathHistoryService!.handlePathUpdated(contact);
+    }
+
+    notifyListeners();
+
+    // Show notification for new contact (advertisement)
+    if (isNewContact && _appSettingsService != null) {
+      final settings = _appSettingsService!.settings;
+      if (settings.notificationsEnabled && settings.notifyOnNewAdvert) {
+        _notificationService.showAdvertNotification(
+          contactName: contact.name,
+          contactType: contact.typeLabel,
+          contactId: contact.publicKeyHex,
+        );
+      }
+    }
+
+    if (!_isLoadingContacts) {
+      unawaited(_persistContacts());
+    }
+  }
+
   Future<void> _persistContacts() async {
     await _contactStore.saveContacts(_contacts);
   }
@@ -3285,6 +3371,136 @@ class MeshCoreConnector extends ChangeNotifier {
 
     super.dispose();
   }
+
+  _updateLocationandAdvert(Position position) async {
+    final snapToGridCenter = _sparseLocationLogger?.snapToGridCenter(
+      position: position,
+      cellSizeMeters: 0.001,
+    );
+    double lat = snapToGridCenter?.latitude ?? 0.0;
+    double lon = snapToGridCenter?.longitude ?? 0.0;
+
+    if (lat == 0.0 && lon == 0.0) {
+      debugPrint('Invalid location (0,0), skipping advert');
+      return;
+    }
+
+    await sendFrame(buildSetOtherParamsFrame(true, 1, 1, 0));
+    await setNodeLocation(lat: lat, lon: lon);
+    await sendSelfAdvert(flood: true);
+    _selfLatitude = lat;
+    _selfLongitude = lon;
+    notifyListeners();
+  }
+
+  void _handleRxData(Uint8List frame) {
+    final packet = BufferReader(frame);
+    packet.skipBytes(3); // Skip frame type byte
+    //final snr = packet.readByte() / 4.0;
+    //final rssi = packet.readByte();
+    final header = packet.readByte();
+    //final routeType = header & 0x03;
+    final payloadType = (header >> 2) & 0x0F;
+    //final payloadVer = (header >> 6) & 0x03;
+
+    if (packet.remaining <= 0) return;
+    final pathLen = packet.readByte();
+
+    if (packet.remaining < pathLen) return;
+    final pathBytes = packet.readBytes(pathLen);
+
+    if (packet.remaining <= 0) return;
+    final payload = packet.readBytes(packet.remaining);
+
+    switch (payloadType) {
+      case payloadTypeADVERT:
+        _handlePayloadAdvertReceived(payload, pathBytes);
+        break;
+      default:
+    }
+  }
+
+  void _handlePayloadAdvertReceived(Uint8List frame, Uint8List path) {
+    final advert = BufferReader(frame);
+    if (advert.remaining <= 32) return;
+    final publicKey = advert.readBytes(32);
+    final contactKeyHex = publicKey
+        .map((b) => b.toRadixString(16).padLeft(2, '0'))
+        .join();
+    if (advert.remaining <= 4) return;
+    final timestamp = advert.readInt32LE();
+    if (advert.remaining <= 64) return;
+    advert.skipBytes(64); // Skip signature for now
+    if (advert.remaining <= 1) return;
+    final flags = advert.readByte();
+    final type = flags & 0x0F;
+    final hasLocation = (flags & 0x10) != 0;
+    //final hasFeature1 = (flags & 0x20) != 0;
+    //final hasFeature2 = (flags & 0x40) != 0;
+    final hasName = (flags & 0x80) != 0;
+    double latitude = 0.0;
+    double longitude = 0.0;
+    if (hasLocation && advert.remaining >= 8) {
+      latitude = advert.readInt32LE() / 1e6;
+      longitude = advert.readInt32LE() / 1e6;
+    }
+    String name = '';
+    if (hasName && advert.remaining > 0) {
+      name = advert.readString();
+    }
+    // Check if this is a new contact
+    final isNewContact = !_knownContactKeys.contains(contactKeyHex);
+    if (isNewContact) {
+      _handleContactAdvert(
+        Contact(
+          publicKey: publicKey,
+          name: name,
+          type: type,
+          pathLength: path.length,
+          path: path,
+          latitude: latitude,
+          longitude: longitude,
+          lastSeen: DateTime.fromMillisecondsSinceEpoch(timestamp * 1000),
+        ),
+      );
+      return;
+    }
+
+    final existingIndex = _contacts.indexWhere(
+      (c) => c.publicKeyHex == contactKeyHex,
+    );
+
+    if (existingIndex >= 0) {
+      final existing = _contacts[existingIndex];
+      final mergedLastMessageAt = existing.lastMessageAt.isAfter(DateTime.now())
+          ? DateTime.now()
+          : existing.lastMessageAt;
+
+      appLogger.info(
+        'Refreshing contact ${existing.name}: devicePath=${existing.pathLength}, existingOverride=${existing.pathOverride}',
+        tag: 'Connector',
+      );
+
+      // CRITICAL: Preserve user's path override when contact is refreshed from device
+      _contacts[existingIndex] = existing.copyWith(
+        latitude: hasLocation ? latitude : existing.latitude,
+        longitude: hasLocation ? longitude : existing.longitude,
+        name: hasName ? name : existing.name,
+        path: path,
+        pathLength: path.length,
+        lastMessageAt: mergedLastMessageAt,
+        lastSeen: DateTime.fromMillisecondsSinceEpoch(timestamp * 1000),
+        pathOverride: existing.pathOverride, // Preserve user's path choice
+        pathOverrideBytes: existing.pathOverrideBytes,
+      );
+
+      appLogger.info(
+        'After merge: pathOverride=${_contacts[existingIndex].pathOverride}, devicePath=${_contacts[existingIndex].pathLength}',
+        tag: 'Connector',
+      );
+      notifyListeners();
+    }
+  }
 }
 
 const int _phRouteMask = 0x03;

lib/connector/meshcore_protocol.dart

@@ -151,6 +151,7 @@ const int cmdGetContactByKey = 30;
 const int cmdGetChannel = 31;
 const int cmdSetChannel = 32;
 const int cmdSendTracePath = 36;
+const int cmdSetOtherParams = 38;
 const int cmdGetRadioSettings = 57;
 const int cmdGetTelemetryReq = 39;
 const int cmdGetCustomVar = 40;
@@ -212,6 +213,30 @@ const int advTypeRepeater = 2;
 const int advTypeRoom = 3;
 const int advTypeSensor = 4;
 
+// Payload Types
+const int payloadTypeREQ =
+    0x00; // request (prefixed with dest/src hashes, MAC) (enc data: timestamp, blob)
+const int payloadTypeRESPONSE =
+    0x01; // response to REQ or ANON_REQ (prefixed with dest/src hashes, MAC) (enc data: timestamp, blob)
+const int payloadTypeTXTMSG =
+    0x02; // a plain text message (prefixed with dest/src hashes, MAC) (enc data: timestamp, text)
+const int payloadTypeACK = 0x03; // a simple ack
+const int payloadTypeADVERT = 0x04; // a node advertising its Identity
+const int payloadTypeGRPTXT =
+    0x05; // an (unverified) group text message (prefixed with channel hash, MAC) (enc data: timestamp, "name: msg")
+const int payloadTypeGRPDATA =
+    0x06; // an (unverified) group datagram (prefixed with channel hash, MAC) (enc data: timestamp, blob)
+const int payloadTypeANONREQ =
+    0x07; // generic request (prefixed with dest_hash, ephemeral pub_key, MAC) (enc data: ...)
+const int payloadTypePATH =
+    0x08; // returned path (prefixed with dest/src hashes, MAC) (enc data: path, extra)
+const int payloadTypeTRACE = 0x09; // trace a path, collecting SNI for each hop
+const int payloadTypeMULTIPART = 0x0A; // packet is one of a set of packets
+const int payloadTypeCONTROL = 0x0B; // a control/discovery packet
+//...
+const int payloadTypeRawCustom =
+    0x0F; // custom packet as raw bytes, for applications with custom encryption, payloads, etc
+
 // Sizes
 const int pubKeySize = 32;
 const int maxPathSize = 64;
@@ -777,3 +802,22 @@ Uint8List buildZeroHopContact(Uint8List pubKey) {
   writer.writeBytes(pubKey);
   return writer.toBytes();
 }
+
+// Build CMD_SET_OTHER_PARAMS frame
+// Format: [cmd][allowAutoAddContacts][allowTelemetryFlags][advertLocationPolicy][multiAcks]
+Uint8List buildSetOtherParamsFrame(
+  bool allowAutoAddContacts,
+  int allowTelemetryFlags,
+  int advertLocationPolicy,
+  int multiAcks,
+) {
+  final writer = BufferWriter();
+  writer.writeByte(cmdSetOtherParams);
+  writer.writeByte(
+    allowAutoAddContacts ? 0x00 : 0x01,
+  ); // Allow Auto Add Contacts
+  writer.writeByte(allowTelemetryFlags); // Allow Telemetry Flags
+  writer.writeByte(advertLocationPolicy); // Advertisement Location Policy
+  writer.writeByte(multiAcks); // Multi Acknowledgements
+  return writer.toBytes();
+}

lib/l10n/app_en.arb

@@ -619,6 +619,7 @@
   "map_sharedPin": "Shared pin",
   "map_joinRoom": "Join Room",
   "map_manageRepeater": "Manage Repeater",
+  "map_updateMyLocation": "Update Location",
   "mapCache_title": "Offline Map Cache",
   "mapCache_selectAreaFirst": "Select an area to cache first",
   "mapCache_noTilesToDownload": "No tiles to download for this area",

lib/main.dart

@@ -1,5 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_localizations/flutter_localizations.dart';
+import 'package:meshcore_open/services/sparse_location_logger.dart';
 import 'l10n/app_localizations.dart';
 import 'package:provider/provider.dart';
 
@@ -33,7 +34,7 @@ void main() async {
   final appDebugLogService = AppDebugLogService();
   final backgroundService = BackgroundService();
   final mapTileCacheService = MapTileCacheService();
-
+  final sparseLocationLogger = SparseLocationLogger();
   // Load settings
   await appSettingsService.loadSettings();
 
@@ -56,6 +57,7 @@ void main() async {
     bleDebugLogService: bleDebugLogService,
     appDebugLogService: appDebugLogService,
     backgroundService: backgroundService,
+    sparseLocationLogger: sparseLocationLogger,
   );
 
   await connector.loadContactCache();
@@ -76,6 +78,7 @@ void main() async {
       bleDebugLogService: bleDebugLogService,
       appDebugLogService: appDebugLogService,
       mapTileCacheService: mapTileCacheService,
+      sparseLocationLogger: sparseLocationLogger,
     ),
   );
 }
@@ -89,6 +92,7 @@ class MeshCoreApp extends StatelessWidget {
   final BleDebugLogService bleDebugLogService;
   final AppDebugLogService appDebugLogService;
   final MapTileCacheService mapTileCacheService;
+  final SparseLocationLogger sparseLocationLogger;
 
   const MeshCoreApp({
     super.key,
@@ -100,6 +104,7 @@ class MeshCoreApp extends StatelessWidget {
     required this.bleDebugLogService,
     required this.appDebugLogService,
     required this.mapTileCacheService,
+    required this.sparseLocationLogger,
   });
 
   @override

lib/screens/map_screen.dart

@@ -275,6 +275,17 @@ class _MapScreenState extends State<MapScreen> {
                         ),
                       ),
                     ),
+                    PopupMenuItem(
+                      child: Row(
+                        children: [
+                          const Icon(Icons.refresh),
+                          const SizedBox(width: 8),
+                          Text(context.l10n.map_updateMyLocation),
+                        ],
+                      ),
+                      onTap: () =>
+                          connector.sparseLocationLogger?.updateMyLocation(),
+                    ),
                   ],
                   icon: const Icon(Icons.more_vert),
                 ),
@@ -357,8 +368,8 @@ class _MapScreenState extends State<MapScreen> {
                               connector.selfLatitude!,
                               connector.selfLongitude!,
                             ),
-                            width: 35,
+                            width: 40,
-                            height: 35,
+                            height: 40,
                             child: Container(
                               padding: const EdgeInsets.all(4),
                               decoration: BoxDecoration(

lib/screens/settings_screen.dart

@@ -490,6 +490,8 @@ class _SettingsScreenState extends State<SettingsScreen> {
     final latController = TextEditingController();
     final lonController = TextEditingController();
     final intervalController = TextEditingController();
+    bool isLogging = connector.sparseLocationLogger?.isLogging() ?? false;
+
     latController.text = connector.selfLatitude?.toStringAsFixed(6) ?? '';
     lonController.text = connector.selfLongitude?.toStringAsFixed(6) ?? '';
 
@@ -534,6 +536,20 @@ class _SettingsScreenState extends State<SettingsScreen> {
                   signed: true,
                 ),
               ),
+              const SizedBox(height: 16),
+              FeatureToggleRow(
+                title: "GPS Logging",
+                subtitle: "Enable GPS logging on the device",
+                value: isLogging,
+                onChanged: (value) async {
+                  setDialogState(() => isLogging = value);
+                  if (value) {
+                    await connector.sparseLocationLogger?.startLogging();
+                  } else {
+                    await connector.sparseLocationLogger?.stopLogging();
+                  }
+                },
+              ),
               if (hasGPS) ...[
                 const SizedBox(height: 16),
                 TextField(

lib/services/sparse_location_logger.dart

@@ -0,0 +1,244 @@
+import 'dart:async';
+import 'dart:io';
+import 'dart:math' as math;
+
+import 'package:flutter/widgets.dart';
+import 'package:geolocator/geolocator.dart';
+import 'package:gpx/gpx.dart';
+import 'package:path_provider/path_provider.dart';
+import 'package:permission_handler/permission_handler.dart';
+import 'package:share_plus/share_plus.dart';
+
+class SparseLocationLogger {
+  static const double distanceThresholdMiles = 0.25;
+  static const double distanceThresholdMeters =
+      distanceThresholdMiles * 1609.34;
+  static const double headingChangeThresholdDeg = 35.0;
+  static const double minSpeedForTurnKmh = 8.0;
+  static const double minTime = 120.0; // seconds
+
+  Position? _lastLoggedPosition;
+  double? _lastHeading;
+  DateTime? _lastLoggedTime;
+  StreamSubscription<Position>? _positionStream;
+  Timer? _timer;
+  Function(Position position)? _onNewLogPoint;
+  // GPX structures
+  final Gpx _gpx = Gpx();
+  Trkseg _currentSegment = Trkseg(); // one segment for the whole session
+
+  File? _gpxFile;
+
+  bool _isInitialized = false;
+
+  void initialize(Function(Position position) onNewLogPoint) {
+    _onNewLogPoint = onNewLogPoint;
+  }
+
+  Future<bool> getPremissons() async {
+    // Permissions & service check (same as before)
+    var status = await Permission.location.request();
+    if (!status.isGranted) {
+      debugPrint('Location permission denied');
+      return false;
+    }
+
+    bool serviceEnabled = await Geolocator.isLocationServiceEnabled();
+    if (!serviceEnabled) {
+      debugPrint('Location services disabled');
+      return false;
+    }
+    return true;
+  }
+
+  Future<void> startLogging() async {
+    if (!await getPremissons()) {
+      return;
+    }
+
+    // Prepare files
+    final directory = await getApplicationDocumentsDirectory();
+    final timestamp = DateTime.now()
+        .toIso8601String()
+        .replaceAll(':', '-')
+        .split('.')
+        .first;
+    _gpxFile = File('${directory.path}/track_$timestamp.gpx');
+
+    // Init GPX metadata
+    _gpx.metadata = Metadata(
+      name: 'Sparse Track ${DateTime.now().toString().split(' ').first}',
+      desc: 'Sparse GPS log: ~every 1.5 mi or significant turns',
+      time: DateTime.now(),
+    );
+
+    // Add one track with one segment
+    final track = Trk(name: 'Main Track');
+    _currentSegment = Trkseg();
+    track.trksegs.add(_currentSegment);
+    _gpx.trks.add(track);
+
+    _isInitialized = true;
+
+    // Start location stream
+    _positionStream = Geolocator.getPositionStream(
+      locationSettings: const LocationSettings(
+        accuracy: LocationAccuracy.high,
+        distanceFilter: 152, // meters (~0.16 mi) - helps battery
+      ),
+    ).listen(_onPositionReceived);
+
+    // Also poll via timer as fallback
+    _timer = Timer.periodic(Duration(seconds: (minTime / 2).toInt()), (
+      _,
+    ) async {
+      final position = await Geolocator.getCurrentPosition();
+      await _onPositionReceived(position);
+    });
+
+    _lastLoggedPosition = null;
+    _lastHeading = null;
+    _lastLoggedTime = null;
+
+    debugPrint('Sparse GPX logging started → ${_gpxFile?.path}');
+  }
+
+  Future<void> stopLogging() async {
+    await _positionStream?.cancel();
+    _positionStream = null;
+    _timer?.cancel();
+    _timer = null;
+
+    if (_isInitialized && _currentSegment.trkpts.isNotEmpty) {
+      // Write GPX file on stop
+      final xmlString = GpxWriter().asString(_gpx, pretty: true);
+
+      await _gpxFile?.writeAsString(xmlString);
+
+      await SharePlus.instance.share(
+        ShareParams(
+          text: 'Sparse GPS track',
+          subject: 'Sparse GPS track',
+          files: [XFile(_gpxFile?.path ?? '')],
+        ),
+      );
+
+      await _gpxFile?.delete();
+    }
+
+    debugPrint('Logging stopped');
+  }
+
+  Future<void> updateMyLocation() async {
+    if (!await getPremissons()) {
+      return;
+    }
+
+    try {
+      final position = await Geolocator.getCurrentPosition();
+      _onNewLogPoint?.call(position);
+    } catch (e) {
+      debugPrint('Error updating location: $e');
+    }
+  }
+
+  Future<void> _onPositionReceived(Position position) async {
+    final now = DateTime.now();
+    final speedKmh = position.speed * 3.6;
+    final heading = position.heading;
+
+    bool shouldLog = false;
+    String reason = '';
+
+    if (_lastLoggedPosition == null) {
+      shouldLog = true;
+      reason = 'start';
+    } else {
+      final distanceMeters = Geolocator.distanceBetween(
+        _lastLoggedPosition!.latitude,
+        _lastLoggedPosition!.longitude,
+        position.latitude,
+        position.longitude,
+      );
+
+      if (distanceMeters >= distanceThresholdMeters) {
+        shouldLog = true;
+        reason =
+            'distance (${(distanceMeters / 1609.34).toStringAsFixed(2)} mi)';
+      } else if (speedKmh > minSpeedForTurnKmh && _lastHeading != null) {
+        double delta = (heading - _lastHeading!).abs();
+        delta = math.min(delta, 360 - delta);
+        if (delta > headingChangeThresholdDeg) {
+          shouldLog = true;
+          reason = 'turn (${delta.toStringAsFixed(1)}°)';
+        }
+      } else if (_lastLoggedTime != null) {
+        final elapsed = now.difference(_lastLoggedTime!).inSeconds;
+        if (elapsed >= minTime && distanceMeters >= distanceThresholdMeters) {
+          shouldLog = true;
+          reason = 'time (${elapsed}s)';
+        }
+      }
+    }
+
+    if (shouldLog) {
+      // Create GPX Waypoint (trkpt)
+      final pt = Wpt(
+        lat: position.latitude,
+        lon: position.longitude,
+        ele: position.altitude, // if available
+        time: now,
+        extensions: {
+          "course": ?heading.isFinite ? heading : null,
+          "speed": ?speedKmh > 0 ? speedKmh / 3.6 : null, // GPX speed in m/s
+        },
+        // You can add hdop, vdop, etc. from position if desired
+      );
+
+      _currentSegment.trkpts.add(pt);
+      _onNewLogPoint?.call(position);
+      debugPrint('Logged point: ${pt.lat}, ${pt.lon} ($reason)');
+
+      _lastLoggedPosition = position;
+      _lastHeading = heading;
+      _lastLoggedTime = now;
+    } else {
+      debugPrint('Skipped point: ${position.latitude}, ${position.longitude}');
+    }
+  }
+
+  Position snapToGridCenter({
+    required Position position,
+    required double cellSizeMeters,
+  }) {
+    Position snappedPosition = position;
+    // Snap latitude
+    final latFloor =
+        (position.latitude / cellSizeMeters).floor() * cellSizeMeters;
+    final snappedLat = latFloor + (cellSizeMeters / 2);
+
+    // Snap longitude
+    final lonFloor =
+        (position.longitude / cellSizeMeters).floor() * cellSizeMeters;
+    final snappedLon = lonFloor + (cellSizeMeters / 2);
+
+    snappedPosition = Position(
+      latitude: snappedLat,
+      longitude: snappedLon,
+      altitude: position.altitude,
+      accuracy: position.accuracy,
+      heading: position.heading,
+      speed: position.speed,
+      speedAccuracy: position.speedAccuracy,
+      altitudeAccuracy: position.altitudeAccuracy,
+      headingAccuracy: position.headingAccuracy,
+      timestamp: position.timestamp,
+    );
+
+    return snappedPosition;
+  }
+
+  Future<String> getGpxFilePath() async => _gpxFile?.path ?? 'Not started';
+  bool isLogging() => _positionStream != null;
+  int getPointCount() => _currentSegment.trkpts.length;
+}

macos/Flutter/GeneratedPluginRegistrant.swift

@@ -7,6 +7,7 @@ import Foundation
 
 import flutter_blue_plus_darwin
 import flutter_local_notifications
+import geolocator_apple
 import mobile_scanner
 import package_info_plus
 import share_plus
@@ -18,6 +19,7 @@ import wakelock_plus
 func RegisterGeneratedPlugins(registry: FlutterPluginRegistry) {
   FlutterBluePlusPlugin.register(with: registry.registrar(forPlugin: "FlutterBluePlusPlugin"))
   FlutterLocalNotificationsPlugin.register(with: registry.registrar(forPlugin: "FlutterLocalNotificationsPlugin"))
+  GeolocatorPlugin.register(with: registry.registrar(forPlugin: "GeolocatorPlugin"))
   MobileScannerPlugin.register(with: registry.registrar(forPlugin: "MobileScannerPlugin"))
   FPPPackageInfoPlusPlugin.register(with: registry.registrar(forPlugin: "FPPPackageInfoPlusPlugin"))
   SharePlusMacosPlugin.register(with: registry.registrar(forPlugin: "SharePlusMacosPlugin"))

pubspec.lock

@@ -69,10 +69,10 @@ packages:
     dependency: "direct main"
     description:
       name: characters
-      sha256: faf38497bda5ead2a8c7615f4f7939df04333478bf32e4173fcb06d428b5716b
+      sha256: f71061c654a3380576a52b451dd5532377954cf9dbd272a78fc8479606670803
       url: "https://pub.dev"
     source: hosted
-    version: "1.4.1"
+    version: "1.4.0"
   checked_yaml:
     dependency: transitive
     description:
@@ -341,6 +341,70 @@ packages:
     description: flutter
     source: sdk
     version: "0.0.0"
+  geoclue:
+    dependency: transitive
+    description:
+      name: geoclue
+      sha256: c2a998c77474fc57aa00c6baa2928e58f4b267649057a1c76738656e9dbd2a7f
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.1.1"
+  geolocator:
+    dependency: "direct main"
+    description:
+      name: geolocator
+      sha256: "79939537046c9025be47ec645f35c8090ecadb6fe98eba146a0d25e8c1357516"
+      url: "https://pub.dev"
+    source: hosted
+    version: "14.0.2"
+  geolocator_android:
+    dependency: transitive
+    description:
+      name: geolocator_android
+      sha256: "179c3cb66dfa674fc9ccbf2be872a02658724d1c067634e2c427cf6df7df901a"
+      url: "https://pub.dev"
+    source: hosted
+    version: "5.0.2"
+  geolocator_apple:
+    dependency: transitive
+    description:
+      name: geolocator_apple
+      sha256: dbdd8789d5aaf14cf69f74d4925ad1336b4433a6efdf2fce91e8955dc921bf22
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.3.13"
+  geolocator_linux:
+    dependency: transitive
+    description:
+      name: geolocator_linux
+      sha256: c4e966f0a7a87e70049eac7a2617f9e16fd4c585a26e4330bdfc3a71e6a721f3
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.2.3"
+  geolocator_platform_interface:
+    dependency: transitive
+    description:
+      name: geolocator_platform_interface
+      sha256: "30cb64f0b9adcc0fb36f628b4ebf4f731a2961a0ebd849f4b56200205056fe67"
+      url: "https://pub.dev"
+    source: hosted
+    version: "4.2.6"
+  geolocator_web:
+    dependency: transitive
+    description:
+      name: geolocator_web
+      sha256: b1ae9bdfd90f861fde8fd4f209c37b953d65e92823cb73c7dee1fa021b06f172
+      url: "https://pub.dev"
+    source: hosted
+    version: "4.1.3"
+  geolocator_windows:
+    dependency: transitive
+    description:
+      name: geolocator_windows
+      sha256: "175435404d20278ffd220de83c2ca293b73db95eafbdc8131fe8609be1421eb6"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.2.5"
   glob:
     dependency: transitive
     description:
@@ -357,6 +421,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.3.0"
+  gsettings:
+    dependency: transitive
+    description:
+      name: gsettings
+      sha256: "1b0ce661f5436d2db1e51f3c4295a49849f03d304003a7ba177d01e3a858249c"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.2.8"
   hooks:
     dependency: transitive
     description:
@@ -489,26 +561,26 @@ packages:
     dependency: transitive
     description:
       name: matcher
-      sha256: "12956d0ad8390bbcc63ca2e1469c0619946ccb52809807067a7020d57e647aa6"
+      sha256: dc58c723c3c24bf8d3e2d3ad3f2f9d7bd9cf43ec6feaa64181775e60190153f2
       url: "https://pub.dev"
     source: hosted
-    version: "0.12.18"
+    version: "0.12.17"
   material_color_utilities:
     dependency: transitive
     description:
       name: material_color_utilities
-      sha256: "9c337007e82b1889149c82ed242ed1cb24a66044e30979c44912381e9be4c48b"
+      sha256: f7142bb1154231d7ea5f96bc7bde4bda2a0945d2806bb11670e30b850d56bdec
       url: "https://pub.dev"
     source: hosted
-    version: "0.13.0"
+    version: "0.11.1"
   meta:
     dependency: transitive
     description:
       name: meta
-      sha256: "1741988757a65eb6b36abe716829688cf01910bbf91c34354ff7ec1c3de2b349"
+      sha256: "23f08335362185a5ea2ad3a4e597f1375e78bce8a040df5c600c8d3552ef2394"
       url: "https://pub.dev"
     source: hosted
-    version: "1.18.0"
+    version: "1.17.0"
   mgrs_dart:
     dependency: transitive
     description:
@@ -637,6 +709,54 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.3.0"
+  permission_handler:
+    dependency: "direct main"
+    description:
+      name: permission_handler
+      sha256: bc917da36261b00137bbc8896bf1482169cd76f866282368948f032c8c1caae1
+      url: "https://pub.dev"
+    source: hosted
+    version: "12.0.1"
+  permission_handler_android:
+    dependency: transitive
+    description:
+      name: permission_handler_android
+      sha256: "1e3bc410ca1bf84662104b100eb126e066cb55791b7451307f9708d4007350e6"
+      url: "https://pub.dev"
+    source: hosted
+    version: "13.0.1"
+  permission_handler_apple:
+    dependency: transitive
+    description:
+      name: permission_handler_apple
+      sha256: f000131e755c54cf4d84a5d8bd6e4149e262cc31c5a8b1d698de1ac85fa41023
+      url: "https://pub.dev"
+    source: hosted
+    version: "9.4.7"
+  permission_handler_html:
+    dependency: transitive
+    description:
+      name: permission_handler_html
+      sha256: "38f000e83355abb3392140f6bc3030660cfaef189e1f87824facb76300b4ff24"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.1.3+5"
+  permission_handler_platform_interface:
+    dependency: transitive
+    description:
+      name: permission_handler_platform_interface
+      sha256: eb99b295153abce5d683cac8c02e22faab63e50679b937fa1bf67d58bb282878
+      url: "https://pub.dev"
+    source: hosted
+    version: "4.3.0"
+  permission_handler_windows:
+    dependency: transitive
+    description:
+      name: permission_handler_windows
+      sha256: "1a790728016f79a41216d88672dbc5df30e686e811ad4e698bfc51f76ad91f1e"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.2.1"
   petitparser:
     dependency: transitive
     description:
@@ -910,10 +1030,10 @@ packages:
     dependency: transitive
     description:
       name: test_api
-      sha256: "93167629bfc610f71560ab9312acdda4959de4df6fac7492c89ff0d3886f6636"
+      sha256: ab2726c1a94d3176a45960b6234466ec367179b87dd74f1611adb1f3b5fb9d55
       url: "https://pub.dev"
     source: hosted
-    version: "0.7.9"
+    version: "0.7.7"
   timezone:
     dependency: transitive
     description:

pubspec.yaml

@@ -60,6 +60,8 @@ dependencies:
   gpx: ^2.3.0
   path_provider: ^2.1.5
   share_plus: ^12.0.1
+  geolocator: ^14.0.2
+  permission_handler: ^12.0.1
 
 dev_dependencies:
   flutter_test:

windows/flutter/generated_plugin_registrant.cc

@@ -7,12 +7,18 @@
 #include "generated_plugin_registrant.h"
 
 #include <flutter_blue_plus_winrt/flutter_blue_plus_plugin.h>
+#include <geolocator_windows/geolocator_windows.h>
+#include <permission_handler_windows/permission_handler_windows_plugin.h>
 #include <share_plus/share_plus_windows_plugin_c_api.h>
 #include <url_launcher_windows/url_launcher_windows.h>
 
 void RegisterPlugins(flutter::PluginRegistry* registry) {
   FlutterBluePlusPluginRegisterWithRegistrar(
       registry->GetRegistrarForPlugin("FlutterBluePlusPlugin"));
+  GeolocatorWindowsRegisterWithRegistrar(
+      registry->GetRegistrarForPlugin("GeolocatorWindows"));
+  PermissionHandlerWindowsPluginRegisterWithRegistrar(
+      registry->GetRegistrarForPlugin("PermissionHandlerWindowsPlugin"));
   SharePlusWindowsPluginCApiRegisterWithRegistrar(
       registry->GetRegistrarForPlugin("SharePlusWindowsPluginCApi"));
   UrlLauncherWindowsRegisterWithRegistrar(

windows/flutter/generated_plugins.cmake

@@ -4,6 +4,8 @@
 
 list(APPEND FLUTTER_PLUGIN_LIST
   flutter_blue_plus_winrt
+  geolocator_windows
+  permission_handler_windows
   share_plus
   url_launcher_windows
 )