DoorDash-Style Delivery App

class DeliveryTracker extends StatefulWidget {
  @override
  _DeliveryTrackerState createState() => _DeliveryTrackerState();
}

class _DeliveryTrackerState extends State<DeliveryTracker> {
  GoogleMapController? _mapController;
  StreamSubscription<Position>? _positionStream;
  
  @override
  void initState() {
    super.initState();
    _startTracking();
  }
  
  void _startTracking() {
    _positionStream = Geolocator.getPositionStream(
      locationSettings: LocationSettings(
        accuracy: LocationAccuracy.high,
        distanceFilter: 10,
      ),
    ).listen((Position position) {
      _updateDriverLocation(position);
    });
  }
  
  void _updateDriverLocation(Position position) {
    final latLng = LatLng(position.latitude, position.longitude);
    _mapController?.animateCamera(
      CameraUpdate.newLatLng(latLng),
    );
    
    // Update Firebase with new location
    FirebaseDatabase.instance
      .ref('deliveries/${widget.orderId}/location')
      .set({
        'lat': position.latitude,
        'lng': position.longitude,
        'timestamp': ServerValue.timestamp,
      });
  }
}