Add WMS support and measurement functionality

- Implemented WMS layer handling for Slovenian aerial imagery and overlays for cadastral parcels and forest roads.
- Added distance measurement feature allowing users to measure distances on the map with long press interactions.
- Updated localization files for Croatian, Italian, and Slovenian languages to include new measurement and WMS-related strings.
- Enhanced the map layer model to support WMS-specific properties.
- Introduced a new tile provider for debugging WMS requests.
- Updated the drawing toolbar to include measurement mode and clear measurement functionality.
- Integrated SharedPreferences to persist overlay visibility states across app sessions.
- Added utility functions for handling the Slovenian coordinate reference system (EPSG:3794).

lib/providers/drawing_provider.dart

@@ -6,7 +6,7 @@ import '../models/map_drawing.dart';
 import '../utils/drawing_message_parser.dart';
 
 /// Drawing mode state
-enum DrawingMode { none, line, rectangle }
+enum DrawingMode { none, line, rectangle, measure }
 
 /// Provider for managing map drawings
 class DrawingProvider with ChangeNotifier {
@@ -26,6 +26,11 @@ class DrawingProvider with ChangeNotifier {
   List<LatLng> _currentLinePoints = [];
   LatLng? _rectangleStartPoint;
 
+  // Distance measurement state
+  LatLng? _measurementPoint1;
+  LatLng? _measurementPoint2;
+  double? _measuredDistance; // in meters
+
   // Getters
   DrawingMode get drawingMode => _drawingMode;
   Color get selectedColor => _selectedColor;
@@ -46,6 +51,9 @@ class DrawingProvider with ChangeNotifier {
   List<LatLng> get currentLinePoints => List.unmodifiable(_currentLinePoints);
   LatLng? get rectangleStartPoint => _rectangleStartPoint;
   bool get isDrawing => _drawingMode != DrawingMode.none;
+  LatLng? get measurementPoint1 => _measurementPoint1;
+  LatLng? get measurementPoint2 => _measurementPoint2;
+  double? get measuredDistance => _measuredDistance;
 
   /// Initialize and load saved drawings
   Future<void> initialize() async {
@@ -126,8 +134,9 @@ class DrawingProvider with ChangeNotifier {
 
   /// Update rectangle end point (for preview)
   void updateRectangleEndPoint(LatLng endPoint) {
-    if (_drawingMode != DrawingMode.rectangle || _rectangleStartPoint == null)
+    if (_drawingMode != DrawingMode.rectangle || _rectangleStartPoint == null) {
       return;
+    }
 
     // Create preview rectangle
     _currentDrawing = RectangleDrawing(
@@ -195,11 +204,47 @@ class DrawingProvider with ChangeNotifier {
     notifyListeners();
   }
 
+  /// Set first measurement point
+  void setMeasurementPoint1(LatLng point) {
+    if (_drawingMode != DrawingMode.measure) return;
+
+    _measurementPoint1 = point;
+    _measurementPoint2 = null;
+    _measuredDistance = null;
+    notifyListeners();
+  }
+
+  /// Set second measurement point and calculate distance
+  void setMeasurementPoint2(LatLng point) {
+    if (_drawingMode != DrawingMode.measure || _measurementPoint1 == null) return;
+
+    _measurementPoint2 = point;
+    _measuredDistance = _calculateDistance(_measurementPoint1!, point);
+    notifyListeners();
+  }
+
+  /// Calculate distance between two points using Haversine formula
+  double _calculateDistance(LatLng point1, LatLng point2) {
+    const Distance distance = Distance();
+    return distance.as(LengthUnit.Meter, point1, point2);
+  }
+
+  /// Clear measurement points
+  void clearMeasurement() {
+    _measurementPoint1 = null;
+    _measurementPoint2 = null;
+    _measuredDistance = null;
+    notifyListeners();
+  }
+
   /// Cancel current drawing in progress
   void _cancelCurrentDrawing() {
     _currentLinePoints = [];
     _rectangleStartPoint = null;
     _currentDrawing = null;
+    _measurementPoint1 = null;
+    _measurementPoint2 = null;
+    _measuredDistance = null;
   }
 
   /// Clear current drawing (public method)

lib/providers/map_provider.dart

@@ -1,5 +1,6 @@
 import 'package:flutter/foundation.dart';
 import 'package:latlong2/latlong.dart';
+import 'package:shared_preferences/shared_preferences.dart';
 import '../models/location_trail.dart';
 import '../models/map_drawing.dart';
 
@@ -16,6 +17,10 @@ class MapProvider with ChangeNotifier {
   bool _isTrailVisible = true;
   final List<LocationTrail> _trailHistory = [];
 
+  // WMS overlay toggles
+  bool _showCadastralOverlay = false;
+  bool _showForestRoadsOverlay = false;
+
   LatLng? get targetLocation => _targetLocation;
   double? get targetZoom => _targetZoom;
   bool get shouldAnimate => _shouldAnimate;
@@ -27,6 +32,10 @@ class MapProvider with ChangeNotifier {
   List<LocationTrail> get trailHistory => List.unmodifiable(_trailHistory);
   bool get isTrailActive => _currentTrail?.isActive ?? false;
 
+  // WMS overlay getters
+  bool get showCadastralOverlay => _showCadastralOverlay;
+  bool get showForestRoadsOverlay => _showForestRoadsOverlay;
+
   void navigateToLocation({
     required LatLng location,
     double zoom = 15.0,
@@ -207,4 +216,33 @@ class MapProvider with ChangeNotifier {
     if (_currentTrail == null) return Duration.zero;
     return _currentTrail!.duration;
   }
+
+  /// Toggle cadastral parcels overlay
+  Future<void> toggleCadastralOverlay() async {
+    _showCadastralOverlay = !_showCadastralOverlay;
+    notifyListeners();
+    await _saveOverlayState();
+  }
+
+  /// Toggle forest roads overlay
+  Future<void> toggleForestRoadsOverlay() async {
+    _showForestRoadsOverlay = !_showForestRoadsOverlay;
+    notifyListeners();
+    await _saveOverlayState();
+  }
+
+  /// Load overlay state from SharedPreferences
+  Future<void> loadOverlayState() async {
+    final prefs = await SharedPreferences.getInstance();
+    _showCadastralOverlay = prefs.getBool('map_show_cadastral_overlay') ?? false;
+    _showForestRoadsOverlay = prefs.getBool('map_show_forest_roads_overlay') ?? false;
+    notifyListeners();
+  }
+
+  /// Save overlay state to SharedPreferences
+  Future<void> _saveOverlayState() async {
+    final prefs = await SharedPreferences.getInstance();
+    await prefs.setBool('map_show_cadastral_overlay', _showCadastralOverlay);
+    await prefs.setBool('map_show_forest_roads_overlay', _showForestRoadsOverlay);
+  }
 }