add support for token validation on login page

lib/components/login/login.dart

@@ -1,10 +1,37 @@
 import 'package:flutter/material.dart';
+import 'package:go_router/go_router.dart';
 import 'package:mileograph_flutter/services/authservice.dart';
 import 'package:provider/provider.dart';
 
-class LoginScreen extends StatelessWidget {
+class LoginScreen extends StatefulWidget {
   const LoginScreen({super.key});
 
+  @override
+  State<LoginScreen> createState() => _LoginScreenState();
+}
+
+class _LoginScreenState extends State<LoginScreen> {
+  bool _checkingSession = true;
+
+  @override
+  void initState() {
+    super.initState();
+    WidgetsBinding.instance.addPostFrameCallback((_) => _checkExistingSession());
+  }
+
+  Future<void> _checkExistingSession() async {
+    final auth = context.read<AuthService>();
+    try {
+      final valid = await auth.validateStoredToken();
+      if (!valid) return;
+      await auth.tryRestoreSession();
+      if (!mounted) return;
+      context.go('/');
+    } finally {
+      if (mounted) setState(() => _checkingSession = false);
+    }
+  }
+
   @override
   Widget build(BuildContext context) {
     return Scaffold(
@@ -24,7 +51,7 @@ class LoginScreen extends StatelessWidget {
                         color: Theme.of(context).textTheme.bodyLarge?.color,
                       ),
                     ),
-                    TextSpan(
+                    const TextSpan(
                       text: "O",
                       style: TextStyle(color: Colors.red),
                     ),
@@ -35,18 +62,27 @@ class LoginScreen extends StatelessWidget {
                       ),
                     ),
                   ],
-                  style: TextStyle(
+                  style: const TextStyle(
                     decoration: TextDecoration.none,
                     color: Colors.white,
-                  fontFamily: "Tomatoes",
-                  fontSize: 50,
+                    fontFamily: "Tomatoes",
+                    fontSize: 50,
+                  ),
                 ),
               ),
-            ),
-            const SizedBox(height: 50),
-            LoginPanel(),
-          ],
-        ),
+              if (_checkingSession)
+                const Padding(
+                  padding: EdgeInsets.only(top: 12),
+                  child: SizedBox(
+                    height: 24,
+                    width: 24,
+                    child: CircularProgressIndicator(strokeWidth: 2),
+                  ),
+                ),
+              const SizedBox(height: 50),
+              const LoginPanel(),
+            ],
+          ),
         ),
       ),
     );

lib/components/pages/new_entry.dart

@@ -2,6 +2,7 @@ import 'dart:async';
 import 'dart:convert';
 
 import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
 import 'package:intl/intl.dart';
 import 'package:mileograph_flutter/components/calculator/calculator.dart';
 import 'package:mileograph_flutter/components/pages/traction.dart';
@@ -444,10 +445,12 @@ class _NewEntryPageState extends State<NewEntryPage> {
       });
       _startController.text = data['start'] ?? '';
       _endController.text = data['end'] ?? '';
-      _headcodeController.text = data['headcode'] ?? '';
+      _headcodeController.text =
+          data['headcode'] is String ? data['headcode'].toUpperCase() : '';
       _notesController.text = data['notes'] ?? '';
       _mileageController.text = data['mileage'] ?? '';
-      _networkController.text = data['network'] ?? '';
+      _networkController.text =
+          data['network'] is String ? data['network'].toUpperCase() : '';
     } catch (_) {
       // Ignore corrupt draft data
     } finally {
@@ -572,9 +575,11 @@ class _NewEntryPageState extends State<NewEntryPage> {
                       ),
                     ),
                   ],
-                ),
+              ),
               TextFormField(
                 controller: _headcodeController,
+                textCapitalization: TextCapitalization.characters,
+                inputFormatters: const [_UpperCaseTextFormatter()],
                 decoration: const InputDecoration(
                   labelText: 'Headcode',
                   border: OutlineInputBorder(),
@@ -582,6 +587,8 @@ class _NewEntryPageState extends State<NewEntryPage> {
               ),
               TextFormField(
                 controller: _networkController,
+                textCapitalization: TextCapitalization.characters,
+                inputFormatters: const [_UpperCaseTextFormatter()],
                 decoration: const InputDecoration(
                   labelText: 'Network',
                   border: OutlineInputBorder(),
@@ -817,6 +824,21 @@ class _NewEntryPageState extends State<NewEntryPage> {
   }
 }
 
+class _UpperCaseTextFormatter extends TextInputFormatter {
+  const _UpperCaseTextFormatter();
+
+  @override
+  TextEditingValue formatEditUpdate(
+    TextEditingValue oldValue,
+    TextEditingValue newValue,
+  ) {
+    return newValue.copyWith(
+      text: newValue.text.toUpperCase(),
+      selection: newValue.selection,
+    );
+  }
+}
+
 class _CalculatorPickerPage extends StatelessWidget {
   const _CalculatorPickerPage({required this.onResult});
   final ValueChanged<RouteResult> onResult;

lib/services/authservice.dart

@@ -72,8 +72,8 @@ class AuthService extends ChangeNotifier {
 
   Future<void> tryRestoreSession() async {
     if (_restoring || _user != null) return;
-      _restoring = true;
-      try {
+    _restoring = true;
+    try {
       // read token from secure storage (with fallback)
       final token = await _tokenStorage.getToken();
       if (token == null || token.isEmpty) return;
@@ -100,6 +100,24 @@ class AuthService extends ChangeNotifier {
     }
   }
 
+  Future<bool> validateStoredToken() async {
+    final token = await _tokenStorage.getToken();
+    if (token == null || token.isEmpty) return false;
+    try {
+      await api.get(
+        '/validate',
+        headers: {
+          'Authorization': 'Bearer $token',
+          'accept': 'application/json',
+        },
+      );
+      return true;
+    } catch (_) {
+      await _clearToken();
+      return false;
+    }
+  }
+
   Future<void> _persistToken(String token) async {
     await _tokenStorage.setToken(token);
   }