transition 1

lib/features/auth/application/splash_screen.dart

@@ -0,0 +1,66 @@
+import 'dart:convert';
+import 'package:flutter/material.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import '../../auth/data/token_storage.dart';
+import '../../../main.dart';
+import 'package:go_router/go_router.dart';
+
+class SplashScreen extends ConsumerStatefulWidget {
+  const SplashScreen({super.key});
+  @override
+  ConsumerState<SplashScreen> createState() => _SplashState();
+}
+
+class _SplashState extends ConsumerState<SplashScreen> {
+  @override
+  void initState() {
+    super.initState();
+    _boot();
+  }
+
+  Future<void> _boot() async {
+    final tokens = ref.read(tokenStorageProvider);
+    // 1) Versuch: vorhandenes Access prüfen
+    final access = await tokens.access;
+    final isValid = _isJwtValid(access);
+
+    if (!isValid) {
+      // 2) Refresh versuchen
+      await tokens.refreshAccess();
+    }
+
+    final access2 = await tokens.access;
+    final authed = _isJwtValid(access2);
+
+    if (!mounted) return;
+    if (authed) {
+      context.go('/igel');
+    } else {
+      context.go('/login');
+    }
+  }
+
+  bool _isJwtValid(String? jwt) {
+    if (jwt == null || jwt.isEmpty) return false;
+    try {
+      final parts = jwt.split('.');
+      if (parts.length != 3) return false;
+      final payload = jsonDecode(
+              utf8.decode(base64Url.decode(base64Url.normalize(parts[1]))))
+          as Map<String, dynamic>;
+      final exp = (payload['exp'] as num?)?.toInt();
+      if (exp == null) return true; // kein exp => als gültig betrachten
+      final now = DateTime.now().millisecondsSinceEpoch ~/ 1000;
+      return now < exp - 15; // kleine Toleranz
+    } catch (_) {
+      return false;
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return const Scaffold(
+      body: Center(child: CircularProgressIndicator()),
+    );
+  }
+}

lib/features/auth/data/token_storage.dart

@@ -39,4 +39,22 @@ class TokenStorage {
       await clear();
     }
   }
+
+  Future<bool> hasValidAccessToken() async {
+    final a = await access;
+    if (a == null || a.isEmpty) return false;
+    try {
+      final parts = a.split('.');
+      if (parts.length != 3) return false;
+      final payload = jsonDecode(
+              utf8.decode(base64Url.decode(base64Url.normalize(parts[1]))))
+          as Map<String, dynamic>;
+      final exp = (payload['exp'] as num?)?.toInt();
+      if (exp == null) return true;
+      final now = DateTime.now().millisecondsSinceEpoch ~/ 1000;
+      return now < exp - 15;
+    } catch (_) {
+      return false;
+    }
+  }
 }