Add logout button

Mobile/lib/api.dart

@@ -1,4 +1,5 @@
 import 'package:flutter/material.dart';
+import 'package:shared_preferences/shared_preferences.dart';
 import 'package:http/http.dart' as http;
 import 'dart:convert';
 
@@ -51,3 +52,30 @@ Future<String?> request(BuildContext context, ApiService service, String method,
 
   return response.body;
 }
+
+Future<bool> isLoggedIn(BuildContext context) async {
+  final messenger = ScaffoldMessenger.of(context);
+  final prefs = await SharedPreferences.getInstance();
+
+  final token = prefs.getString('token');
+  if (token == null) return false;
+
+  try {
+    String base64 = token.split('.')[1];
+    base64 += List.filled(4 - base64.length % 4, '=').join();
+
+    final payload = jsonDecode(String.fromCharCodes(base64Decode(base64)));
+
+    if (payload['exp'] < DateTime.now().millisecondsSinceEpoch / 1000) {
+      messenger.showSnackBar(const SnackBar(content: Text('Token expired, please sign in again')));
+      prefs.remove('token');
+      return false;
+    }
+  } catch (e) {
+    messenger.showSnackBar(const SnackBar(content: Text('Invalid token, please sign in again')));
+    prefs.remove('token');
+    return false;
+  }
+
+  return true;
+}

Mobile/lib/login.dart

@@ -52,11 +52,11 @@ class _LoginPageState extends State<LoginPage> {
               const Text('Password'),
               TextField(controller: passwordInput, obscureText: true, enableSuggestions: false, autocorrect: false),
               const SizedBox(height: 30),
-              ElevatedButton(onPressed: _login, child: const Text('Log ind')),
+              ElevatedButton(onPressed: _login, child: const Text('Login')),
               const SizedBox(height: 10),
               TextButton(
-                child: const Text('Registrer konto'),
+                child: const Text('Register account'),
-                onPressed: () => Navigator.pushReplacement(context, MaterialPageRoute(builder: (context) => const RegisterPage(title: 'Registrer'))),
+                onPressed: () => Navigator.pushReplacement(context, MaterialPageRoute(builder: (context) => const RegisterPage(title: 'Register'))),
               )
             ]
           )

Mobile/lib/main.dart

@@ -1,8 +1,10 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
-import "package:latlong2/latlong.dart";
+import 'package:latlong2/latlong.dart';
 import 'package:mobile/register.dart';
-import "login.dart";
+import 'package:shared_preferences/shared_preferences.dart';
+import 'login.dart';
+import 'api.dart' as api;
 
 void main() {
   runApp(const MyApp());
@@ -33,7 +35,9 @@ class MyHomePage extends StatefulWidget {
 }
 
 class _MyHomePageState extends State<MyHomePage> {
+  final GlobalKey<ScaffoldState> _scaffoldKey = GlobalKey<ScaffoldState>();
   int _selectedIndex = 0;
+  bool _isLoggedIn = false;
 
   void _onItemTapped(int index) {
     setState(() {
@@ -41,9 +45,40 @@ class _MyHomePageState extends State<MyHomePage> {
     });
   }
 
+  void _logout() async {
+    final prefs = await SharedPreferences.getInstance();
+
+    prefs.remove('token');
+    setState(() => _isLoggedIn = false);
+
+    if (mounted) {
+      ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('Successfully logged out')));
+      Navigator.pop(context);
+    }
+  }
+
+  Future<void> _postNavigationCallback(dynamic _) async {
+    final isLoggedIn = await api.isLoggedIn(context);
+    setState(() => _isLoggedIn = isLoggedIn);
+
+    // Close sidebar
+    if (mounted && _scaffoldKey.currentState?.isDrawerOpen == true) {
+      Navigator.pop(context);
+    }
+  }
+
+  @override
+  void didChangeDependencies() {
+    super.didChangeDependencies();
+
+    api.isLoggedIn(context)
+        .then((value) => setState(() => _isLoggedIn = value));
+  }
+
   @override
   Widget build(BuildContext context) {
     return Scaffold(
+      key: _scaffoldKey,
       appBar: AppBar(
         backgroundColor: Theme.of(context).colorScheme.inversePrimary,
         title: Text(widget.title),
@@ -61,13 +96,11 @@ class _MyHomePageState extends State<MyHomePage> {
       ),
       floatingActionButton: Row(
         mainAxisAlignment: MainAxisAlignment.end,
-        children: [
+        children: _isLoggedIn ? [] : [
           FloatingActionButton(
             onPressed: () {
-              Navigator.push(
+              Navigator.push(context, MaterialPageRoute(builder: (context) => const LoginPage(title: "Login")))
-                  context,
+                .then(_postNavigationCallback);
-                  MaterialPageRoute(
-                      builder: (context) => const LoginPage(title: "Login")));
             },
             tooltip: 'Login',
             child: const Icon(Icons.login),
@@ -125,6 +158,15 @@ class _MyHomePageState extends State<MyHomePage> {
               thickness: 2,
               indent: 40,
             ),
+            ...(
+              _isLoggedIn ? [
+                ListTile(
+                  title: const Text('Log out'),
+                  leading: const Icon(Icons.logout),
+                  selected: false,
+                  onTap: _logout,
+                )
+              ] : [
                 ListTile(
                   title: const Text('Register'),
                   leading: const Icon(Icons.add_box_outlined),
@@ -133,11 +175,8 @@ class _MyHomePageState extends State<MyHomePage> {
                     // Update the state of the app
                     _onItemTapped(3);
                     // Then close the drawer
-                Navigator.push(
+                    Navigator.push(context, MaterialPageRoute(builder: (context) => const RegisterPage(title: 'Register')))
-                    context,
+                        .then(_postNavigationCallback);
-                    MaterialPageRoute(
-                        builder: (context) =>
-                            const RegisterPage(title: "Register")));
                   },
                 ),
                 ListTile(
@@ -148,13 +187,13 @@ class _MyHomePageState extends State<MyHomePage> {
                     // Update the state of the app
                     _onItemTapped(4);
                     // Then close the drawer
-                Navigator.push(
+                    Navigator.push(context, MaterialPageRoute(builder: (context) => const LoginPage(title: 'Login')))
-                    context,
+                        .then(_postNavigationCallback);
-                    MaterialPageRoute(
-                        builder: (context) => const LoginPage(title: "Login")));
                   },
-            ),
+                )
-          ],
+              ]
+            )
+          ]
         ),
       );
 }

Mobile/lib/register.dart

@@ -44,7 +44,7 @@ class _RegisterPageState extends State<RegisterPage> {
           child: Column(
             children: [
               const SizedBox(height: 80),
-              const Text('Brugernavn'),
+              const Text('Username'),
               TextField(controller: usernameInput),
               const SizedBox(height: 30),
               const Text('Email'),
@@ -53,11 +53,11 @@ class _RegisterPageState extends State<RegisterPage> {
               const Text('Password'),
               TextField(controller: passwordInput, obscureText: true, enableSuggestions: false, autocorrect: false),
               const SizedBox(height: 30),
-              ElevatedButton(onPressed: _register, child: const Text('Registrer')),
+              ElevatedButton(onPressed: _register, child: const Text('Register')),
               const SizedBox(height: 10),
               TextButton(
-                child: const Text('Log ind'),
+                child: const Text('Login'),
-                onPressed: () => Navigator.pushReplacement(context, MaterialPageRoute(builder: (context) => const LoginPage(title: 'Log ind')))
+                onPressed: () => Navigator.pushReplacement(context, MaterialPageRoute(builder: (context) => const LoginPage(title: 'Login')))
               ),
             ]
           )