Implemented graph structures and digraph

.gitignore

 # Miscellaneous
+.env
 *.class
 *.log
 *.pyc

lib/main.dart

@@ -11,9 +11,11 @@ import 'screens/profile_screen.dart';
 import 'providers/delivery_provider.dart';
 import 'login.dart';
 import 'signup.dart';
+import 'package:flutter_dotenv/flutter_dotenv.dart';
 
 void main() async {
   WidgetsFlutterBinding.ensureInitialized();
+  await dotenv.load(fileName: ".env");
   await Firebase.initializeApp(
     options: DefaultFirebaseOptions.currentPlatform,
   );

lib/models/delivery_address.dart

@@ -6,8 +6,8 @@ class DeliveryAddress {
   final String city;
   final String state;
   final String zipCode;
-  final double? latitude;
-  final double? longitude;
+  double? latitude;
+  double? longitude;
   final String? notes;
   final DateTime createdAt;
 

lib/models/digraph.dart

+// lib/models/digraph.dart
+class Edge {
+  final int to;
+  final int weight; // seconds
+  Edge(this.to, this.weight);
+}
+
+class Digraph {
+  final int n; // number of nodes
+  final List<List<Edge>> adj;
+
+  Digraph(this.n) : adj = List.generate(n, (_) => []);
+
+  void addEdge(int u, int v, int w) {
+    adj[u].add(Edge(v, w));
+  }
+
+  /// Basic Dijkstra returning predecessor and distance arrays
+  Map<String, dynamic> dijkstra(int source) {
+    final dist = List<int>.filled(n, 1 << 30);
+    final prev = List<int?>.filled(n, null);
+    dist[source] = 0;
+
+    final visited = List<bool>.filled(n, false);
+    for (int i = 0; i < n; i++) {
+      int u = -1;
+      int best = 1 << 30;
+      for (int v = 0; v < n; v++) {
+        if (!visited[v] && dist[v] < best) {
+          best = dist[v];
+          u = v;
+        }
+      }
+      if (u == -1) break;
+      visited[u] = true;
+      for (final e in adj[u]) {
+        final alt = dist[u] + e.weight;
+        if (alt < dist[e.to]) {
+          dist[e.to] = alt;
+          prev[e.to] = u;
+        }
+      }
+    }
+    return {'dist': dist, 'prev': prev};
+  }
+
+  List<int> reconstructPath(int source, int target, List<int?> prev) {
+    final path = <int>[];
+    for (int? v = target; v != null; v = prev[v]) {
+      path.insert(0, v);
+      if (v == source) break;
+    }
+    if (path.isEmpty || path.first != source) return [];
+    return path;
+  }
+}

lib/providers/graph_provider.dart

 import 'package:flutter/material.dart';
+import '../models/delivery_address.dart';
+import '../models/digraph.dart';
+import '../services/google_api_service.dart';
 
 class GraphNode {
   final String id;
@@ -81,4 +84,75 @@ class GraphProvider extends ChangeNotifier {
       notifyListeners();
     }
   }
+
+
+  // ===== T7 / Routing Graph Fields =====
+  final GoogleApiService apiService;
+
+  GraphProvider({GoogleApiService? apiService})
+    : apiService = apiService ?? GoogleApiService();
+  // _api = GoogleApiService();
+
+
+  List<DeliveryAddress> addresses = [];
+  Digraph? graph;
+  List<List<int>>? matrix;
+
+// ===== T7 Methods =====
+  /// Build the routing graph from delivery addresses
+  Future<void> buildGraphFromAddresses(List<DeliveryAddress> input) async {
+    addresses = input;
+
+    // 1) Geocode addresses using fullAddress getter
+    final fullAddresses = addresses.map((a) => a.fullAddress).toList();
+    final geocodeMap = await apiService.geocodeAddresses(fullAddresses);
+
+    // Update latitude / longitude in DeliveryAddress objects
+    for (int i = 0; i < addresses.length; i++) {
+      final loc = geocodeMap[fullAddresses[i]];
+      if (loc != null) {
+        addresses[i].latitude = loc.lat;
+        addresses[i].longitude = loc.lng;
+      } else {
+        addresses[i].latitude = null;
+        addresses[i].longitude = null;
+      }
+    }
+
+    // Filter valid addresses
+    final valid = addresses.where((a) => a.hasCoordinates).toList();
+    final origins = valid.map((a) => LatLng(a.latitude!, a.longitude!)).toList();
+
+    // 2) Distance matrix
+    matrix = await apiService.getDistanceMatrix(origins);
+
+    // 3) Build digraph for routing
+    graph = Digraph(origins.length);
+    for (int i = 0; i < origins.length; i++) {
+      for (int j = 0; j < origins.length; j++) {
+        if (i == j) continue;
+        final w = matrix![i][j];
+        if (w < (1 << 29)) {
+          graph!.addEdge(i, j, w);
+        }
+      }
+    }
+
+    notifyListeners();
+  }
+
+  /// Compute shortest route between two nodes in the routing graph
+  Map<String, dynamic> shortestRoute(int startIndex, int endIndex) {
+    if (graph == null) return {'distanceSeconds': 0, 'path': []};
+
+    final res = graph!.dijkstra(startIndex);
+    final prev = res['prev'] as List<int?>;
+    final dist = res['dist'] as List<int>;
+    final path = graph!.reconstructPath(startIndex, endIndex, prev);
+
+    return {'distanceSeconds': dist[endIndex], 'path': path};
+  }
+
 }
+
+

lib/screens/graph_screen.dart

 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
 import '../providers/graph_provider.dart';
+import '../providers/delivery_provider.dart';
+import 'package:google_maps_flutter/google_maps_flutter.dart';
+// import '../models/delivery_address.dart';
 
-class GraphScreen extends StatelessWidget {
+class GraphScreen extends StatefulWidget {
   const GraphScreen({super.key});
 
+  @override
+  State<GraphScreen> createState() => _GraphScreenState();
+}
+
+class _GraphScreenState extends State<GraphScreen> {
+  bool _isLoading = false;
+  String _statusMessage = "";
+  List<int> _samplePath = [];
+  int _totalNodes = 0;
+
+  GoogleMapController? _mapController;
+  final Set<Marker> _markers = {};
+  final Set<Polyline> _polylines = {};
+
   @override
   Widget build(BuildContext context) {
+    final deliveryProvider = Provider.of<DeliveryProvider>(context);
+    final graphProvider = Provider.of<GraphProvider>(context);
+
     return Scaffold(
       appBar: AppBar(
         backgroundColor: Theme.of(context).colorScheme.inversePrimary,
@@ -18,27 +38,131 @@ class GraphScreen extends StatelessWidget {
         actions: [
           IconButton(
             icon: const Icon(Icons.add),
-            onPressed: () {
-              // Add node functionality
-              _showAddNodeDialog(context);
-            },
+            onPressed: () => _showAddNodeDialog(context),
           ),
           IconButton(
             icon: const Icon(Icons.refresh),
             onPressed: () {
-              Provider.of<GraphProvider>(context, listen: false).clearGraph();
+              graphProvider.clearGraph();
             },
           ),
         ],
       ),
-      body: Consumer<GraphProvider>(
+      body: Column(
+        children: [
+          Padding(
+            padding: const EdgeInsets.all(16.0),
+            child: ElevatedButton(
+              onPressed: _isLoading
+                  ? null
+                  : () async {
+                setState(() {
+                  _isLoading = true;
+                  _statusMessage = "Building graph...";
+                  _samplePath = [];
+                  _totalNodes = 0;
+                  _markers.clear();
+                  _polylines.clear();
+                });
+
+                try {
+                  // Build graph from addresses
+                  await graphProvider.buildGraphFromAddresses(
+                      deliveryProvider.addresses);
+
+                  final graph = graphProvider.graph;
+                  if (graph != null) {
+                    setState(() {
+                      _totalNodes = graph.n;
+
+                      if (graph.n >= 2) {
+                        final res =
+                        graphProvider.shortestRoute(0, graph.n - 1);
+                        _samplePath = List<int>.from(res['path']);
+                        _statusMessage =
+                        "Graph built! Nodes: ${graph.n}";
+                      } else {
+                        _statusMessage = "Graph built, but not enough nodes";
+                      }
+
+                      // Optional: markers for all addresses
+                      for (int i = 0; i < deliveryProvider.addresses.length; i++) {
+                        final addr = deliveryProvider.addresses[i];
+                        if (addr.hasCoordinates) {
+                          _markers.add(Marker(
+                            markerId: MarkerId(addr.id),
+                            position: LatLng(addr.latitude!, addr.longitude!),
+                            infoWindow: InfoWindow(title: addr.fullAddress),
+                          ));
+                        }
+                      }
+
+                      // Optional: polyline for sample path
+                      if (_samplePath.isNotEmpty) {
+                        final points = _samplePath
+                            .map((idx) => LatLng(
+                            deliveryProvider.addresses[idx].latitude!,
+                            deliveryProvider.addresses[idx].longitude!))
+                            .toList();
+                        _polylines.add(Polyline(
+                            polylineId: const PolylineId("sample_path"),
+                            points: points,
+                            color: Colors.blue,
+                            width: 4));
+                      }
+                    });
+                  } else {
+                    setState(() {
+                      _statusMessage = "Graph could not be built";
+                    });
+                  }
+                } catch (e) {
+                  setState(() {
+                    _statusMessage = "Error building graph: $e";
+                  });
+                } finally {
+                  setState(() {
+                    _isLoading = false;
+                  });
+                }
+              },
+              child: _isLoading
+                  ? const CircularProgressIndicator(color: Colors.white)
+                  : const Text("Build Routes"),
+            ),
+          ),
+          Text(_statusMessage),
+          if (_samplePath.isNotEmpty)
+            Text("Sample shortest path: $_samplePath"),
+          if (_totalNodes > 0) Text("Total nodes: $_totalNodes"),
+          const SizedBox(height: 16),
+          Expanded(
+            child: Consumer<GraphProvider>(
               builder: (context, graphProvider, child) {
+                return graphProvider.nodes.isEmpty
+                    ? _buildEmptyGraphPlaceholder()
+                    : CustomPaint(
+                  painter: GraphPainter(
+                      graphProvider.nodes, graphProvider.edges),
+                  child: Container(),
+                );
+              },
+            ),
+          ),
+        ],
+      ),
+      floatingActionButton: FloatingActionButton(
+        onPressed: () => _showAddNodeDialog(context),
+        tooltip: 'Add Node',
+        child: const Icon(Icons.add),
+      ),
+    );
+  }
+
+  Widget _buildEmptyGraphPlaceholder() {
     return Center(
       child: Column(
         mainAxisAlignment: MainAxisAlignment.center,
-              children: [
-                if (graphProvider.nodes.isEmpty)
-                  Column(
         children: [
           Icon(
             Icons.account_tree_outlined,
@@ -48,46 +172,22 @@ class GraphScreen extends StatelessWidget {
           const SizedBox(height: 16),
           Text(
             'No graph data yet',
-                        style: Theme.of(context).textTheme.headlineSmall?.copyWith(
-                          color: Colors.grey[600],
-                        ),
+            style: Theme.of(context)
+                .textTheme
+                .headlineSmall
+                ?.copyWith(color: Colors.grey[600]),
           ),
           const SizedBox(height: 8),
           Text(
-                        'Add nodes to start building your graph',
-                        style: Theme.of(context).textTheme.bodyMedium?.copyWith(
-                          color: Colors.grey[500],
-                        ),
-                      ),
-                    ],
-                  )
-                else
-                  Expanded(
-                    child: CustomPaint(
-                      painter: GraphPainter(graphProvider.nodes, graphProvider.edges),
-                      child: Container(),
-                    ),
-                  ),
-                const SizedBox(height: 20),
-                Text(
-                  'Nodes: ${graphProvider.nodes.length}',
-                  style: Theme.of(context).textTheme.bodyLarge,
-                ),
-                Text(
-                  'Edges: ${graphProvider.edges.length}',
-                  style: Theme.of(context).textTheme.bodyLarge,
+            'Add nodes to start building your graph or use "Build Routes"',
+            style: Theme.of(context)
+                .textTheme
+                .bodyMedium
+                ?.copyWith(color: Colors.grey[500]),
           ),
         ],
       ),
     );
-        },
-      ),
-      floatingActionButton: FloatingActionButton(
-        onPressed: () => _showAddNodeDialog(context),
-        tooltip: 'Add Node',
-        child: const Icon(Icons.add),
-      ),
-    );
   }
 
   void _showAddNodeDialog(BuildContext context) {
@@ -144,8 +244,6 @@ class GraphPainter extends CustomPainter {
       ..strokeWidth = 2.0
       ..style = PaintingStyle.stroke;
 
-
-    // Draw edges first
     for (final edge in edges) {
       final startNode = nodes.firstWhere((n) => n.id == edge.fromId);
       final endNode = nodes.firstWhere((n) => n.id == edge.toId);
@@ -157,7 +255,6 @@ class GraphPainter extends CustomPainter {
       );
     }
 
-    // Draw nodes
     for (final node in nodes) {
       canvas.drawCircle(
         Offset(node.x, node.y),
@@ -165,7 +262,6 @@ class GraphPainter extends CustomPainter {
         nodePaint,
       );
 
-      // Draw node label
       final textPainter = TextPainter(
         text: TextSpan(
           text: node.label,

lib/services/google_api_service.dart

+// lib/services/google_api_service.dart
+import 'dart:convert';
+import 'package:flutter_dotenv/flutter_dotenv.dart';
+import 'package:http/http.dart' as http;
+
+class LatLng {
+  final double lat;
+  final double lng;
+  LatLng(this.lat, this.lng);
+}
+
+class GoogleApiService {
+  final String key = dotenv.env['GOOGLE_MAPS_API_KEY'] ?? '';
+
+  Future<LatLng?> geocodeAddress(String address) async {
+    final encoded = Uri.encodeComponent(address);
+    final url = Uri.parse(
+      'https://maps.googleapis.com/maps/api/geocode/json?address=$encoded&key=$key',
+    );
+    final res = await http.get(url);
+    if (res.statusCode != 200) return null;
+    final data = json.decode(res.body);
+    if (data['status'] != 'OK' || (data['results'] as List).isEmpty) return null;
+    final loc = data['results'][0]['geometry']['location'];
+    return LatLng(loc['lat'], loc['lng']);
+  }
+
+  /// Geocode many addresses in parallel (with small concurrency)
+  Future<Map<String, LatLng?>> geocodeAddresses(List<String> addresses) async {
+    final Map<String, LatLng?> out = {};
+    // Simple sequential approach (easier to respect rate limits). You can parallelize (Future.wait) cautiously.
+    for (final a in addresses) {
+      out[a] = await geocodeAddress(a);
+    }
+    return out;
+  }
+
+  /// Build a distance matrix (durations in seconds). Returns matrix[i][j] = duration (int), or large = unreachable
+  Future<List<List<int>>> getDistanceMatrix(List<LatLng> origins, {String travelMode = 'driving'}) async {
+    final originStr = origins.map((o) => '${o.lat},${o.lng}').join('|');
+    final destinationStr = originStr; // origins==destinations for full matrix
+    final url = Uri.parse(
+      'https://maps.googleapis.com/maps/api/distancematrix/json'
+          '?origins=$originStr'
+          '&destinations=$destinationStr'
+          '&mode=$travelMode'
+          '&units=metric'
+          '&key=$key',
+    );
+    final res = await http.get(url);
+    if (res.statusCode != 200) {
+      throw Exception('DistanceMatrix failed: ${res.statusCode}');
+    }
+    final data = json.decode(res.body);
+    if (data['status'] != 'OK') {
+      throw Exception('DistanceMatrix response: ${data['status']}');
+    }
+
+    final rows = data['rows'] as List;
+    final n = rows.length;
+    final List<List<int>> matrix = List.generate(n, (_) => List.filled(n, 1 << 30));
+    for (int i = 0; i < n; i++) {
+      final elements = rows[i]['elements'] as List;
+      for (int j = 0; j < elements.length; j++) {
+        final el = elements[j];
+        if (el['status'] == 'OK' && el['duration'] != null) {
+          matrix[i][j] = el['duration']['value']; // seconds
+        } else {
+          matrix[i][j] = 1 << 30; // unreachable sentinel
+        }
+      }
+    }
+    return matrix;
+  }
+}

pubspec.lock

@@ -342,6 +342,14 @@ packages:
     description: flutter
     source: sdk
     version: "0.0.0"
+  flutter_dotenv:
+    dependency: "direct main"
+    description:
+      name: flutter_dotenv
+      sha256: b7c7be5cd9f6ef7a78429cabd2774d3c4af50e79cb2b7593e3d5d763ef95c61b
+      url: "https://pub.dev"
+    source: hosted
+    version: "5.2.1"
   flutter_driver:
     dependency: transitive
     description: flutter

pubspec.yaml

@@ -25,6 +25,7 @@ dependencies:
   google_sign_in: ^6.2.1
   image_picker: ^1.0.4
   firebase_storage: ^11.5.6
+  flutter_dotenv: ^5.0.2
 
 dev_dependencies:
   flutter_test:
@@ -39,5 +40,5 @@ flutter:
   uses-material-design: true
   
   assets:
-    - assets/images/
+#    - assets/images/
     - assets/icons/

test/mocks/mock_services.dart

+import 'package:graph_go/services/google_api_service.dart';
+import 'package:mockito/annotations.dart';
+
+@GenerateMocks([GoogleApiService])
+void main() {}

test/mocks/mock_services.mocks.dart

+// Mocks generated by Mockito 5.4.6 from annotations
+// in graph_go/test/mocks/mock_services.dart.
+// Do not manually edit this file.
+
+// ignore_for_file: no_leading_underscores_for_library_prefixes
+import 'dart:async' as _i4;
+
+import 'package:graph_go/services/google_api_service.dart' as _i2;
+import 'package:mockito/mockito.dart' as _i1;
+import 'package:mockito/src/dummies.dart' as _i3;
+
+// ignore_for_file: type=lint
+// ignore_for_file: avoid_redundant_argument_values
+// ignore_for_file: avoid_setters_without_getters
+// ignore_for_file: comment_references
+// ignore_for_file: deprecated_member_use
+// ignore_for_file: deprecated_member_use_from_same_package
+// ignore_for_file: implementation_imports
+// ignore_for_file: invalid_use_of_visible_for_testing_member
+// ignore_for_file: must_be_immutable
+// ignore_for_file: prefer_const_constructors
+// ignore_for_file: unnecessary_parenthesis
+// ignore_for_file: camel_case_types
+// ignore_for_file: subtype_of_sealed_class
+// ignore_for_file: invalid_use_of_internal_member
+
+/// A class which mocks [GoogleApiService].
+///
+/// See the documentation for Mockito's code generation for more information.
+class MockGoogleApiService extends _i1.Mock implements _i2.GoogleApiService {
+  MockGoogleApiService() {
+    _i1.throwOnMissingStub(this);
+  }
+
+  @override
+  String get key => (super.noSuchMethod(
+        Invocation.getter(#key),
+        returnValue: _i3.dummyValue<String>(
+          this,
+          Invocation.getter(#key),
+        ),
+      ) as String);
+
+  @override
+  _i4.Future<_i2.LatLng?> geocodeAddress(String? address) =>
+      (super.noSuchMethod(
+        Invocation.method(
+          #geocodeAddress,
+          [address],
+        ),
+        returnValue: _i4.Future<_i2.LatLng?>.value(),
+      ) as _i4.Future<_i2.LatLng?>);
+
+  @override
+  _i4.Future<Map<String, _i2.LatLng?>> geocodeAddresses(
+          List<String>? addresses) =>
+      (super.noSuchMethod(
+        Invocation.method(
+          #geocodeAddresses,
+          [addresses],
+        ),
+        returnValue:
+            _i4.Future<Map<String, _i2.LatLng?>>.value(<String, _i2.LatLng?>{}),
+      ) as _i4.Future<Map<String, _i2.LatLng?>>);
+
+  @override
+  _i4.Future<List<List<int>>> getDistanceMatrix(
+    List<_i2.LatLng>? origins, {
+    String? travelMode = 'driving',
+  }) =>
+      (super.noSuchMethod(
+        Invocation.method(
+          #getDistanceMatrix,
+          [origins],
+          {#travelMode: travelMode},
+        ),
+        returnValue: _i4.Future<List<List<int>>>.value(<List<int>>[]),
+      ) as _i4.Future<List<List<int>>>);
+}

test/providers/delivery_provider_test.dart

@@ -53,7 +53,11 @@ void main() {
         // Arrange
         final address = DeliveryAddress(
           id: 'test-id',
-          fullAddress: '123 Test St, Test City',
+          // fullAddress: '123 Test St, Test City',
+          streetAddress: '123 Test St',
+          city: 'Test City',
+          state: 'NY',
+          zipCode: '10001',
           latitude: 40.7128,
           longitude: -74.0060,
         );
@@ -72,7 +76,11 @@ void main() {
         for (int i = 0; i < 100; i++) {
           final address = DeliveryAddress(
             id: 'test-id-$i',
-            fullAddress: '123 Test St $i, Test City',
+            // fullAddress: '123 Test St $i, Test City',
+            streetAddress: '123 Test St $i',
+            city: 'Test City',
+            state: 'NY',
+            zipCode: '10001',
             latitude: 40.7128,
             longitude: -74.0060,
           );
@@ -81,7 +89,11 @@ void main() {
 
         final extraAddress = DeliveryAddress(
           id: 'extra-id',
-          fullAddress: '123 Extra St, Test City',
+          // fullAddress: '123 Extra St, Test City',
+          streetAddress: '123 Extra St',
+          city: 'Test City',
+          state: 'NY',
+          zipCode: '10001',
           latitude: 40.7128,
           longitude: -74.0060,
         );
@@ -99,7 +111,11 @@ void main() {
         // Arrange
         final originalAddress = DeliveryAddress(
           id: 'test-id',
-          fullAddress: '123 Test St, Test City',
+          // fullAddress: '123 Test St, Test City',
+          streetAddress: '123 Test St',
+          city: 'Test City',
+          state: 'NY',
+          zipCode: '10001',
           latitude: 40.7128,
           longitude: -74.0060,
         );
@@ -107,7 +123,11 @@ void main() {
 
         final updatedAddress = DeliveryAddress(
           id: 'test-id',
-          fullAddress: '456 Updated St, Updated City',
+          // fullAddress: '456 Updated St, Updated City',
+          streetAddress: '456 Updated St',
+          city: 'Updated City',
+          state: 'NY',
+          zipCode: '10008',
           latitude: 41.7128,
           longitude: -75.0060,
         );
@@ -125,7 +145,11 @@ void main() {
         // Arrange
         final address = DeliveryAddress(
           id: 'test-id',
-          fullAddress: '123 Test St, Test City',
+          // fullAddress: '123 Test St, Test City',
+          streetAddress: '123 Test St',
+          city: 'Test City',
+          state: 'NY',
+          zipCode: '10001',
           latitude: 40.7128,
           longitude: -74.0060,
         );
@@ -145,19 +169,31 @@ void main() {
         // Add test addresses
         final address1 = DeliveryAddress(
           id: 'addr1',
-          fullAddress: '123 First St, Test City',
+          // fullAddress: '123 First St, Test City',
+          streetAddress: '123 First St',
+          city: 'Test City',
+          state: 'NY',
+          zipCode: '10001',
           latitude: 40.7128,
           longitude: -74.0060,
         );
         final address2 = DeliveryAddress(
           id: 'addr2',
-          fullAddress: '456 Second St, Test City',
+          // fullAddress: '456 Second St, Test City',
+          streetAddress: '456 Second St',
+          city: 'Test City',
+          state: 'NY',
+          zipCode: '10001',
           latitude: 40.7589,
           longitude: -73.9851,
         );
         final address3 = DeliveryAddress(
           id: 'addr3',
-          fullAddress: '789 Third St, Test City',
+          // fullAddress: '789 Third St, Test City',
+          streetAddress: '789 Third St',
+          city: 'Test City',
+          state: 'NY',
+          zipCode: '10001',
           latitude: 40.7505,
           longitude: -73.9934,
         );
@@ -178,9 +214,9 @@ void main() {
         expect(result.name, 'Test Route');
         expect(result.algorithm, RouteAlgorithm.dijkstra);
         expect(result.addresses.length, 3);
-        expect(result.optimizedRoute.length, 3);
+        expect(result.optimizedRoute?.length, 3);
         expect(result.totalDistance, greaterThan(0));
-        expect(result.estimatedTime.inMinutes, greaterThan(0));
+        expect(result.estimatedTime?.inMinutes, greaterThan(0));
       });
 
       test('should optimize route with Nearest Neighbor algorithm', () async {
@@ -194,7 +230,7 @@ void main() {
         expect(result.name, 'NN Route');
         expect(result.algorithm, RouteAlgorithm.nearestNeighbor);
         expect(result.addresses.length, 3);
-        expect(result.optimizedRoute.length, 3);
+        expect(result.optimizedRoute?.length, 3);
       });
 
       test('should throw exception when no addresses available', () async {
@@ -233,7 +269,11 @@ void main() {
         // Arrange
         final invalidAddress = DeliveryAddress(
           id: 'invalid-id',
-          fullAddress: 'Invalid Address That Cannot Be Geocoded',
+          // fullAddress: 'Invalid Address That Cannot Be Geocoded',
+          streetAddress: 'Invalid Address That Cannot Be Geocoded',
+          city: 'Invalid',
+          state: '',
+          zipCode: '',
         );
 
         // Act
@@ -250,7 +290,11 @@ void main() {
         // Arrange
         final address = DeliveryAddress(
           id: 'test-id',
-          fullAddress: '123 Test St, Test City',
+          // fullAddress: '123 Test St, Test City',
+          streetAddress: '123 Test St',
+          city: 'Test City',
+          state: 'NY',
+          zipCode: '10001',
           latitude: 40.7128,
           longitude: -74.0060,
         );

test/providers/google_api_service_test.dart

+import 'package:mockito/annotations.dart';
+import 'package:graph_go/services/google_api_service.dart';
+
+@GenerateMocks([GoogleApiService])
+void main() {}

test/providers/google_api_service_test.mocks.dart

+// Mocks generated by Mockito 5.4.6 from annotations
+// in graph_go/test/providers/google_api_service_test.dart.
+// Do not manually edit this file.
+
+// ignore_for_file: no_leading_underscores_for_library_prefixes
+import 'dart:async' as _i4;
+
+import 'package:graph_go/services/google_api_service.dart' as _i2;
+import 'package:mockito/mockito.dart' as _i1;
+import 'package:mockito/src/dummies.dart' as _i3;
+
+// ignore_for_file: type=lint
+// ignore_for_file: avoid_redundant_argument_values
+// ignore_for_file: avoid_setters_without_getters
+// ignore_for_file: comment_references
+// ignore_for_file: deprecated_member_use
+// ignore_for_file: deprecated_member_use_from_same_package
+// ignore_for_file: implementation_imports
+// ignore_for_file: invalid_use_of_visible_for_testing_member
+// ignore_for_file: must_be_immutable
+// ignore_for_file: prefer_const_constructors
+// ignore_for_file: unnecessary_parenthesis
+// ignore_for_file: camel_case_types
+// ignore_for_file: subtype_of_sealed_class
+// ignore_for_file: invalid_use_of_internal_member
+
+/// A class which mocks [GoogleApiService].
+///
+/// See the documentation for Mockito's code generation for more information.
+class MockGoogleApiService extends _i1.Mock implements _i2.GoogleApiService {
+  MockGoogleApiService() {
+    _i1.throwOnMissingStub(this);
+  }
+
+  @override
+  String get key => (super.noSuchMethod(
+        Invocation.getter(#key),
+        returnValue: _i3.dummyValue<String>(
+          this,
+          Invocation.getter(#key),
+        ),
+      ) as String);
+
+  @override
+  _i4.Future<_i2.LatLng?> geocodeAddress(String? address) =>
+      (super.noSuchMethod(
+        Invocation.method(
+          #geocodeAddress,
+          [address],
+        ),
+        returnValue: _i4.Future<_i2.LatLng?>.value(),
+      ) as _i4.Future<_i2.LatLng?>);
+
+  @override
+  _i4.Future<Map<String, _i2.LatLng?>> geocodeAddresses(
+          List<String>? addresses) =>
+      (super.noSuchMethod(
+        Invocation.method(
+          #geocodeAddresses,
+          [addresses],
+        ),
+        returnValue:
+            _i4.Future<Map<String, _i2.LatLng?>>.value(<String, _i2.LatLng?>{}),
+      ) as _i4.Future<Map<String, _i2.LatLng?>>);
+
+  @override
+  _i4.Future<List<List<int>>> getDistanceMatrix(
+    List<_i2.LatLng>? origins, {
+    String? travelMode = 'driving',
+  }) =>
+      (super.noSuchMethod(
+        Invocation.method(
+          #getDistanceMatrix,
+          [origins],
+          {#travelMode: travelMode},
+        ),
+        returnValue: _i4.Future<List<List<int>>>.value(<List<int>>[]),
+      ) as _i4.Future<List<List<int>>>);
+}

test/providers/graph_provider_test.dart

+import 'package:flutter_test/flutter_test.dart';
+import 'package:mockito/mockito.dart';
+import 'package:graph_go/providers/graph_provider.dart';
+import 'package:graph_go/models/delivery_address.dart';
+import 'google_api_service_test.mocks.dart'; // import the generated mock
+import 'package:graph_go/services/google_api_service.dart';
+
+void main() {
+  late GraphProvider graphProvider;
+  late MockGoogleApiService mockApi;
+
+  setUp(() {
+    mockApi = MockGoogleApiService();
+    // Make sure GraphProvider accepts GoogleApiService via constructor
+    graphProvider = GraphProvider(apiService: mockApi);
+  });
+
+  test('buildGraphFromAddresses populates graph correctly', () async {
+    // Step 1: Create test addresses
+    final testAddresses = [
+      DeliveryAddress(
+        streetAddress: '1600 Amphitheatre Parkway',
+        city: 'Mountain View',
+        state: 'CA',
+        zipCode: '94043',
+      ),
+      DeliveryAddress(
+        streetAddress: '1 Infinite Loop',
+        city: 'Cupertino',
+        state: 'CA',
+        zipCode: '95014',
+      ),
+      DeliveryAddress(
+        streetAddress: '500 Terry A Francois Blvd',
+        city: 'San Francisco',
+        state: 'CA',
+        zipCode: '94158',
+      ),
+    ];
+
+    // Step 2: Mock GoogleApiService responses
+    when(mockApi.geocodeAddresses(any)).thenAnswer((_) async => {
+      testAddresses[0].fullAddress: LatLng(37.422, -122.084),
+      testAddresses[1].fullAddress: LatLng(37.331, -122.030),
+      testAddresses[2].fullAddress: LatLng(37.770, -122.387),
+    });
+
+    when(mockApi.getDistanceMatrix(any)).thenAnswer((_) async => [
+      [0, 1000, 2000],
+      [1000, 0, 1500],
+      [2000, 1500, 0],
+    ]);
+
+    // Step 3: Run the method under test
+    await graphProvider.buildGraphFromAddresses(testAddresses);
+
+    // Step 4: Verify coordinates were populated
+    for (var addr in testAddresses) {
+      expect(addr.hasCoordinates, true);
+    }
+
+    // Step 5: Verify distance matrix
+    expect(graphProvider.matrix!.length, 3);
+    expect(graphProvider.matrix![0][1], 1000);
+
+    // Step 6: Verify digraph adjacency
+    expect(graphProvider.graph!.adj[0].length, 2); // edges to node 1 & 2
+
+    // Step 7: Test shortest path computation
+    final result = graphProvider.shortestRoute(0, 2);
+    expect(result['path'], isNotEmpty);
+    expect(result['distanceSeconds'], 2000);
+  });
+}
+

test/screens/home_screen_maps_test.dart

@@ -6,6 +6,8 @@ import 'package:mockito/mockito.dart';
 import 'package:mockito/annotations.dart';
 import 'package:graph_go/screens/home_screen.dart';
 import 'package:graph_go/providers/delivery_provider.dart';
+import 'package:google_maps_flutter/google_maps_flutter.dart';
+
 
 // Generate mocks
 @GenerateMocks([FirebaseAuth, User, DeliveryProvider])

test/screens/home_screen_test.dart

@@ -8,6 +8,8 @@ import 'package:mockito/annotations.dart';
 import 'package:graph_go/main.dart';
 import 'package:graph_go/screens/home_screen.dart';
 import 'package:graph_go/providers/delivery_provider.dart';
+import 'package:google_maps_flutter/google_maps_flutter.dart';
+
 
 import 'home_screen_test.mocks.dart';