add back button functionality

lib/components/calculator/calculator.dart

@@ -5,31 +5,6 @@ import 'package:mileograph_flutter/services/apiService.dart';
 import 'package:mileograph_flutter/services/dataService.dart';
 import './routeSummaryWidget.dart';
 
-class RouteCalculatorLoader extends StatelessWidget {
-  const RouteCalculatorLoader({super.key});
-
-  @override
-  Widget build(BuildContext context) {
-    final data = context.read<DataService>();
-
-    return FutureBuilder<List<Station>>(
-      future: data.fetchStations(),
-      builder: (context, snapshot) {
-        if (snapshot.connectionState != ConnectionState.done) {
-          return const Center(child: CircularProgressIndicator());
-        }
-
-        if (snapshot.hasError) {
-          return Center(child: Text('Error: ${snapshot.error}'));
-        }
-
-        final stations = snapshot.data!;
-        return RouteCalculator(allStations: stations);
-      },
-    );
-  }
-}
-
 class StationAutocomplete extends StatefulWidget {
   const StationAutocomplete({
     super.key,
@@ -105,16 +80,14 @@ class _StationAutocompleteState extends State<StationAutocomplete> {
 }
 
 class RouteCalculator extends StatefulWidget {
-  final List<Station> allStations;
-
-  const RouteCalculator({super.key, required this.allStations});
+  const RouteCalculator({super.key});
 
   @override
   State<RouteCalculator> createState() => _RouteCalculatorState();
 }
 
 class _RouteCalculatorState extends State<RouteCalculator> {
-  List<String> stations = [''];
+  List<Station> allStations = [];
 
   RouteResult? _routeResult;
   RouteResult? get result => _routeResult;
@@ -122,6 +95,23 @@ class _RouteCalculatorState extends State<RouteCalculator> {
 
   bool _showDetails = false;
 
+  bool _fetched = false;
+
+  @override
+  void didChangeDependencies() {
+    super.didChangeDependencies();
+    if (!_fetched) {
+      _fetched = true;
+      WidgetsBinding.instance.addPostFrameCallback((_) async {
+        final data = context.read<DataService>();
+        final result = await data.fetchStations();
+        if (mounted) {
+          setState(() => allStations = result);
+        }
+      });
+    }
+  }
+
   Future<void> _calculateRoute(List<String> stations) async {
     setState(() {
       _errorMessage = null;
@@ -146,25 +136,29 @@ class _RouteCalculatorState extends State<RouteCalculator> {
   }
 
   void _addStation() {
+    final data = context.read<DataService>();
     setState(() {
-      stations.add('');
+      data.stations.add('');
     });
   }
 
   void _removeStation(int index) {
+    final data = context.read<DataService>();
     setState(() {
-      stations.removeAt(index);
+      data.stations.removeAt(index);
     });
   }
 
   void _updateStation(int index, String value) {
+    final data = context.read<DataService>();
     setState(() {
-      stations[index] = value;
+      data.stations[index] = value;
     });
   }
 
   @override
   Widget build(BuildContext context) {
+    final data = context.watch<DataService>();
     if (_showDetails && _routeResult != null) {
       return RouteDetailsView(
         route: _routeResult!.calculatedRoute,
@@ -180,13 +174,13 @@ class _RouteCalculatorState extends State<RouteCalculator> {
             onReorder: (oldIndex, newIndex) {
               if (newIndex > oldIndex) newIndex -= 1;
               setState(() {
-                final moved = stations.removeAt(oldIndex);
-                stations.insert(newIndex, moved);
+                final moved = data.stations.removeAt(oldIndex);
+                data.stations.insert(newIndex, moved);
               });
             },
-            children: List.generate(stations.length, (index) {
+            children: List.generate(data.stations.length, (index) {
               return Container(
-                key: ValueKey('$index-${stations[index]}'),
+                key: ValueKey('$index-${data.stations[index]}'),
                 margin: const EdgeInsets.symmetric(horizontal: 16, vertical: 4),
                 child: Row(
                   crossAxisAlignment: CrossAxisAlignment.start,
@@ -207,8 +201,8 @@ class _RouteCalculatorState extends State<RouteCalculator> {
                             children: [
                               Expanded(
                                 child: StationAutocomplete(
-                                  allStations: widget.allStations,
-                                  initialValue: stations[index],
+                                  allStations: allStations,
+                                  initialValue: data.stations[index],
                                   onChanged: (val) =>
                                       _updateStation(index, val),
                                 ),
@@ -244,24 +238,34 @@ class _RouteCalculatorState extends State<RouteCalculator> {
         else
           SizedBox.shrink(),
         const SizedBox(height: 10),
-        Row(
-          mainAxisAlignment: MainAxisAlignment.center,
-          children: [
-            ElevatedButton.icon(
-              icon: const Icon(Icons.add),
-              label: const Text('Add Station'),
-              onPressed: _addStation,
-            ),
-            const SizedBox(width: 16),
-            ElevatedButton.icon(
-              icon: const Icon(Icons.route),
-              label: const Text('Calculate Route'),
-              onPressed: () async {
-                await _calculateRoute(stations);
-              },
-            ),
-          ],
+        LayoutBuilder(
+          builder: (context, constraints) {
+            double screenWidth = constraints.maxWidth;
+
+            return Padding(
+              padding: EdgeInsets.only(right: screenWidth < 450 ? 70 : 0),
+              child: Row(
+                mainAxisAlignment: MainAxisAlignment.center,
+                children: [
+                  ElevatedButton.icon(
+                    icon: const Icon(Icons.add),
+                    label: const Text('Add Station'),
+                    onPressed: _addStation,
+                  ),
+                  const SizedBox(width: 16),
+                  ElevatedButton.icon(
+                    icon: const Icon(Icons.route),
+                    label: const Text('Calculate Route'),
+                    onPressed: () async {
+                      await _calculateRoute(data.stations);
+                    },
+                  ),
+                ],
+              ),
+            );
+          },
         ),
+
         const SizedBox(height: 16),
       ],
     );

lib/components/pages/calculator.dart

@@ -5,6 +5,6 @@ import 'package:mileograph_flutter/services/dataService.dart';
 
 class CalculatorPage extends StatelessWidget {
   Widget build(BuildContext context) {
-    return RouteCalculatorLoader();
+    return RouteCalculator();
   }
 }

lib/components/pages/dashboard.dart

@@ -85,7 +85,11 @@ class DashboardHeader extends StatelessWidget {
         Expanded(
           child: ListView(
             scrollDirection: Axis.vertical,
-            children: [TopTractionPanel(), LeaderboardPanel()],
+            children: [
+              TopTractionPanel(),
+              LeaderboardPanel(),
+              SizedBox(height: 80),
+            ],
           ),
         ),
       ],