feat:implementacion grafica

lib/core/router/app_router.dart

@@ -0,0 +1,121 @@
+import 'dart:async';
+
+import 'package:flutter/material.dart';
+import 'package:go_router/go_router.dart';
+
+import '../../features/auth/presentation/bloc/auth_bloc.dart';
+import '../../features/auth/presentation/bloc/auth_state.dart';
+import '../../features/auth/presentation/screens/login_screen.dart';
+import '../../features/auth/presentation/screens/home_screen_placeholder.dart';
+
+/// Rutas nombradas de la aplicación.
+abstract final class AppRoutes {
+  static const String splash = '/';
+  static const String login = '/login';
+  static const String home = '/home';
+}
+
+/// Configuración central de navegación con go_router.
+///
+/// La redirección basada en estado de autenticación garantiza que
+/// rutas protegidas sean inaccesibles sin sesión válida.
+GoRouter createRouter(AuthBloc authBloc) {
+  return GoRouter(
+    initialLocation: AppRoutes.splash,
+    refreshListenable: GoRouterAuthNotifier(authBloc),
+    redirect: (BuildContext context, GoRouterState state) {
+      final authState = authBloc.state;
+      final isAuthenticated = authState is AuthAuthenticated;
+      final isCheckingSession = authState is AuthCheckingSession ||
+          authState is AuthInitial;
+      final currentLocation = state.uri.path;
+
+      // Mientras se verifica la sesión, mostrar splash.
+      if (isCheckingSession) {
+        return currentLocation == AppRoutes.splash ? null : AppRoutes.splash;
+      }
+
+      // Si no está autenticado, ir a login.
+      if (!isAuthenticated) {
+        return currentLocation == AppRoutes.login ? null : AppRoutes.login;
+      }
+
+      // Si está autenticado y en splash o login, ir a home.
+      if (isAuthenticated &&
+          (currentLocation == AppRoutes.login ||
+              currentLocation == AppRoutes.splash)) {
+        return AppRoutes.home;
+      }
+
+      return null; // Sin redirección.
+    },
+    routes: [
+      GoRoute(
+        path: AppRoutes.splash,
+        builder: (context, state) => const _SplashScreen(),
+      ),
+      GoRoute(
+        path: AppRoutes.login,
+        builder: (context, state) => const LoginScreen(),
+      ),
+      GoRoute(
+        path: AppRoutes.home,
+        builder: (context, state) => const HomeScreenPlaceholder(),
+      ),
+    ],
+  );
+}
+
+/// Pantalla de splash mínima mientras se verifica la sesión.
+class _SplashScreen extends StatelessWidget {
+  const _SplashScreen();
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      backgroundColor: const Color(0xFF2E7D32),
+      body: Center(
+        child: Column(
+          mainAxisSize: MainAxisSize.min,
+          children: [
+            const Icon(
+              Icons.recycling_rounded,
+              size: 72,
+              color: Colors.white,
+            ),
+            const SizedBox(height: 24),
+            Text(
+              'WasteNotify',
+              style: Theme.of(context).textTheme.headlineMedium?.copyWith(
+                    color: Colors.white,
+                    fontWeight: FontWeight.bold,
+                    letterSpacing: 1.2,
+                  ),
+            ),
+            const SizedBox(height: 48),
+            const CircularProgressIndicator(
+              valueColor: AlwaysStoppedAnimation<Color>(Colors.white70),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
+/// Notificador que conecta el estado del BLoC con go_router.
+/// Permite que el router reaccione automáticamente a cambios de sesión.
+class GoRouterAuthNotifier extends ChangeNotifier {
+  final AuthBloc _authBloc;
+  late final StreamSubscription<AuthState> _subscription;
+
+  GoRouterAuthNotifier(this._authBloc) {
+    _subscription = _authBloc.stream.listen((_) => notifyListeners());
+  }
+
+  @override
+  void dispose() {
+    _subscription.cancel();
+    super.dispose();
+  }
+}