GNSS eszközhöz való kapcsolódás és bluetooth kommunikáció refraktorálása külön osztályokba

android/app/src/main/AndroidManifest.xml

@@ -9,6 +9,12 @@
             android:name="com.pravera.flutter_foreground_task.service.ForegroundService"
             android:foregroundServiceType="location"
             android:stopWithTask="false"/>
+        <service 
+            android:name="com.baseflow.geolocator.GeolocatorLocationService"
+            android:foregroundServiceType="location"
+            android:stopWithTask="false"
+            android:exported="false"/>
+
 
         <activity
             android:name=".MainActivity"
@@ -42,16 +48,18 @@
     <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
     <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />    
     <uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
+    <uses-permission android:name="android.permission.FOREGROUND_SERVICE_LOCATION"/>
     <uses-permission android:name="android.permission.ACCESS_BACKGROUND_LOCATION"/>
-    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
+    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" android:maxSdkVersion="28" />
-    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
+    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" android:maxSdkVersion="28"  />
-    <uses-permission android:name="android.permission.BLUETOOTH"/>
+    <uses-permission android:name="android.permission.BLUETOOTH" android:maxSdkVersion="30" />
-    <uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>
+    <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" android:maxSdkVersion="30" />
     <!-- <uses-permission android:name="android.permission.BLUETOOTH" android:maxSdkVersion="30"/>
     <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" android:maxSdkVersion="30"/> -->
     <!-- <uses-permission android:name="android.permission.BLUETOOTH" tools:remove="android:maxSdkVersion"/>
     <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" tools:remove="android:maxSdkVersion"/> -->
-    <uses-permission android:name="android.permission.BLUETOOTH_SCAN"/>
+    <uses-permission android:name="android.permission.BLUETOOTH_SCAN"
+        android:usesPermissionFlags="neverForLocation" tools:targetApi="s"/>
     <uses-permission android:name="android.permission.BLUETOOTH_ADVERTISE" />  
     <uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />    
 

lib/services/gnss/ble_gnss_connection.dart

@@ -0,0 +1,111 @@
+// lib/services/gnss/ble_gnss_connection.dart
+import 'dart:async';
+import 'package:flutter_blue_plus/flutter_blue_plus.dart';
+import 'gnss_connection.dart';
+
+// Nordic UART Service — a legelterjedtebb BLE UART profil
+const _nusServiceUuid = '6e400001-b5b3-f393-e0a9-e50e24dcca9e';
+const _nusTxCharUuid = '6e400003-b5b3-f393-e0a9-e50e24dcca9e'; // notify
+const _nusRxCharUuid = '6e400002-b5b3-f393-e0a9-e50e24dcca9e'; // write
+
+class BleGnssConnection implements GnssConnection {
+  @override
+  GnssConnectionType get type => GnssConnectionType.ble;
+
+  final String serviceUuid;
+  final String txCharUuid; // notify (eszköz → telefon)
+
+  BleGnssConnection({
+    this.serviceUuid = _nusServiceUuid,
+    this.txCharUuid = _nusTxCharUuid,
+  });
+
+  BluetoothDevice? _device;
+  StreamSubscription? _notifySub;
+  String _lineBuffer = '';
+
+  final _nmeaController = StreamController<String>.broadcast();
+  final _stateController = StreamController<GnssConnectionState>.broadcast();
+
+  @override
+  Stream<String> get nmeaLines => _nmeaController.stream;
+
+  @override
+  Stream<GnssConnectionState> get connectionState => _stateController.stream;
+
+  @override
+  Future<void> connect(String address) async {
+    _stateController.add(GnssConnectionState.connecting);
+
+    try {
+      _device = BluetoothDevice.fromId(address);
+
+      await _device!.connect(
+          timeout: const Duration(seconds: 10),
+          autoConnect: false,
+          license: License.free);
+
+      // Kapcsolat megszakadás figyelése
+      _device!.connectionState.listen((state) {
+        if (state == BluetoothConnectionState.disconnected) {
+          _stateController.add(GnssConnectionState.disconnected);
+        }
+      });
+
+      // Service discovery
+      final services = await _device!.discoverServices();
+      final gnssService = services.firstWhere(
+        (s) => s.serviceUuid.str.toLowerCase() == serviceUuid.toLowerCase(),
+        orElse: () =>
+            throw Exception('GNSS service nem található: $serviceUuid'),
+      );
+
+      // TX karakterisztika (notify) — eszköztől jönnek az NMEA sorok
+      final txChar = gnssService.characteristics.firstWhere(
+        (c) =>
+            c.characteristicUuid.str.toLowerCase() == txCharUuid.toLowerCase(),
+        orElse: () => throw Exception('TX char nem található: $txCharUuid'),
+      );
+
+      // Notify engedélyezése
+      await txChar.setNotifyValue(true);
+
+      _notifySub = txChar.onValueReceived.listen(_onBleData);
+
+      _stateController.add(GnssConnectionState.connected);
+    } catch (e) {
+      _stateController.add(GnssConnectionState.error);
+      rethrow;
+    }
+  }
+
+  void _onBleData(List<int> bytes) {
+    // BLE csomagok kis méretűek (≤20 byte MTU default),
+    // az NMEA mondatokat össze kell fűzni
+    final chunk = String.fromCharCodes(bytes);
+    _lineBuffer += chunk;
+
+    // Teljes sorok kibocsátása
+    while (_lineBuffer.contains('\n')) {
+      final idx = _lineBuffer.indexOf('\n');
+      final line = _lineBuffer.substring(0, idx).trim();
+      _lineBuffer = _lineBuffer.substring(idx + 1);
+      if (line.isNotEmpty) _nmeaController.add(line);
+    }
+  }
+
+  @override
+  Future<void> disconnect() async {
+    await _notifySub?.cancel();
+    await _device?.disconnect();
+    _stateController.add(GnssConnectionState.disconnected);
+  }
+
+  @override
+  void dispose() {
+    _notifySub?.cancel();
+    _device?.disconnect();
+    _nmeaController.close();
+    _stateController.close();
+  }
+}

lib/services/gnss/bt_serial_gnss_connection.dart

@@ -0,0 +1,94 @@
+// lib/services/gnss/bt_serial_gnss_connection.dart
+import 'dart:async';
+import 'dart:typed_data';
+import 'package:flutter_bluetooth_serial/flutter_bluetooth_serial.dart';
+import 'gnss_connection.dart';
+
+class BtSerialGnssConnection implements GnssConnection {
+  @override
+  GnssConnectionType get type => GnssConnectionType.btSerial;
+
+  BluetoothConnection? _connection;
+  String _messageBuffer = '';
+
+  final _nmeaController = StreamController<String>.broadcast();
+  final _stateController = StreamController<GnssConnectionState>.broadcast();
+
+  @override
+  Stream<String> get nmeaLines => _nmeaController.stream;
+
+  @override
+  Stream<GnssConnectionState> get connectionState => _stateController.stream;
+
+  @override
+  Future<void> connect(String address) async {
+    _stateController.add(GnssConnectionState.connecting);
+    try {
+      _connection = await BluetoothConnection.toAddress(address);
+      _stateController.add(GnssConnectionState.connected);
+      _connection!.input!.listen(
+        _onData,
+        onDone: () {
+          _stateController.add(GnssConnectionState.disconnected);
+        },
+      );
+    } catch (e) {
+      _stateController.add(GnssConnectionState.error);
+      rethrow;
+    }
+  }
+
+  @override
+  Future<void> disconnect() async {
+    await _connection?.close();
+    _connection = null;
+    _stateController.add(GnssConnectionState.disconnected);
+  }
+
+  // A meglévő _onDataReceived logika változatlanul
+  void _onData(Uint8List data) {
+    int backspacesCounter = 0;
+    for (var byte in data) {
+      if (byte == 8 || byte == 127) backspacesCounter++;
+    }
+
+    Uint8List buffer = Uint8List(data.length - backspacesCounter);
+    int bufferIndex = buffer.length;
+    backspacesCounter = 0;
+
+    for (int i = data.length - 1; i >= 0; i--) {
+      if (data[i] == 8 || data[i] == 127) {
+        backspacesCounter++;
+      } else if (backspacesCounter > 0) {
+        backspacesCounter--;
+      } else {
+        buffer[--bufferIndex] = data[i];
+      }
+    }
+
+    final dataString = String.fromCharCodes(buffer);
+    final index = buffer.indexOf(13); // \r
+
+    String sentence;
+    if (~index != 0) {
+      sentence = _messageBuffer + dataString.substring(0, index);
+      _messageBuffer = dataString.substring(index);
+    } else {
+      _messageBuffer += dataString;
+      return;
+    }
+
+    // Soronként kibocsátjuk
+    for (final line in sentence.split('\n')) {
+      final trimmed = line.trim();
+      if (trimmed.isNotEmpty) _nmeaController.add(trimmed);
+    }
+  }
+
+  @override
+  void dispose() {
+    _connection?.close();
+    _nmeaController.close();
+    _stateController.close();
+  }
+}

lib/services/gnss/gnss_connection.dart

@@ -0,0 +1,20 @@
+// lib/services/gnss/gnss_connection.dart
+
+enum GnssConnectionType { btSerial, ble }
+
+enum GnssConnectionState { disconnected, connecting, connected, error }
+
+abstract class GnssConnection {
+  GnssConnectionType get type;
+
+  /// NMEA sorok stream-je — mindkét implementáció ezt adja
+  Stream<String> get nmeaLines;
+
+  /// Kapcsolat állapota
+  Stream<GnssConnectionState> get connectionState;
+
+  Future<void> connect(String address);
+  Future<void> disconnect();
+
+  void dispose();
+}

lib/services/gnss/gnss_service.dart

@@ -0,0 +1,104 @@
+// lib/services/gnss/gnss_service.dart
+import 'dart:async';
+import 'package:get/get.dart';
+import 'package:nmea/nmea.dart';
+import '../../gnss_sentences/gngga.dart';
+import 'gnss_connection.dart';
+import 'bt_serial_gnss_connection.dart';
+import 'ble_gnss_connection.dart';
+
+class GnssService extends GetxService {
+  static GnssService get to => Get.find();
+
+  GnssConnection? _connection;
+
+  // Reaktív állapot — a controllerek Obx-szel figyelhetik
+  final connectionState = GnssConnectionState.disconnected.obs;
+  final activeConnectionType = Rxn<GnssConnectionType>();
+
+  // Parsed NMEA adatok
+  final latitude = 0.0.obs;
+  final longitude = 0.0.obs;
+  final altitude = 0.0.obs;
+  final geoidSeparation = 0.0.obs;
+  final gpsQuality = 0.obs;
+  final utcFix = ''.obs;
+  final satelliteCount = 0.obs;
+  final hdop = 0.0.obs;
+
+  final NmeaDecoder _decoder = NmeaDecoder();
+  StreamSubscription? _nmeaSub;
+  StreamSubscription? _stateSub;
+
+  @override
+  void onInit() {
+    super.onInit();
+    _decoder.registerTalkerSentence('GGA', (l) => Gngga(raw: l));
+  }
+
+  // ── Kapcsolódás ──────────────────────────────────────────────────
+
+  Future<void> connectBtSerial(String macAddress) async {
+    await _disconnect();
+    _connection = BtSerialGnssConnection();
+    activeConnectionType.value = GnssConnectionType.btSerial;
+    await _doConnect(macAddress);
+  }
+
+  Future<void> connectBle(
+    String deviceId, {
+    String? serviceUuid,
+    String? txCharUuid,
+  }) async {
+    await _disconnect();
+    _connection = BleGnssConnection(
+      serviceUuid: serviceUuid ?? '6e400001-b5b3-f393-e0a9-e50e24dcca9e',
+      txCharUuid: txCharUuid ?? '6e400003-b5b3-f393-e0a9-e50e24dcca9e',
+    );
+    activeConnectionType.value = GnssConnectionType.ble;
+    await _doConnect(deviceId);
+  }
+
+  Future<void> _doConnect(String address) async {
+    _stateSub = _connection!.connectionState.listen((s) {
+      connectionState.value = s;
+    });
+    _nmeaSub = _connection!.nmeaLines.listen(_parseNmea);
+    await _connection!.connect(address);
+  }
+
+  Future<void> _disconnect() async {
+    await _nmeaSub?.cancel();
+    await _stateSub?.cancel();
+    await _connection?.disconnect();
+    _connection?.dispose();
+    _connection = null;
+  }
+
+  // ── NMEA parsing — egy helyen, nem háromban ──────────────────────
+
+  void _parseNmea(String line) {
+    if (!line.startsWith('\$GNGGA') && !line.startsWith('\$GPGGA')) return;
+
+    try {
+      final sentence = _decoder.decode(line);
+      if (sentence == null || !sentence.valid || sentence is! Gngga) return;
+      if (sentence.gpsQualityIndicator == 0) return;
+
+      latitude.value = sentence.latitude;
+      longitude.value = sentence.longitude;
+      altitude.value = sentence.altitudeAboveMeanSeaLevel;
+      geoidSeparation.value = sentence.geoidSeparation;
+      gpsQuality.value = sentence.gpsQualityIndicator;
+      utcFix.value = sentence.utcOfPositionFix;
+      satelliteCount.value = sentence.numberOfSvsInUse;
+      hdop.value = sentence.hdop;
+    } catch (_) {}
+  }
+
+  @override
+  void onClose() {
+    _disconnect();
+    super.onClose();
+  }
+}

pubspec.yaml

@@ -70,6 +70,7 @@ dependencies:
   share_plus: ^12.0.1 
   geolocator: ^14.0.2
   flutter_foreground_task: ^9.2.2
+  flutter_blue_plus: ^2.3.2
 
   flutter:
     sdk: flutter