Untitled

import 'package:firebase_auth/firebase_auth.dart';
import 'package:firebase_core/firebase_core.dart';
import 'package:flutter/material.dart';

class HomePage extends StatelessWidget {
  const HomePage({super.key});

  @override
  Widget build(BuildContext context) {
    final user = FirebaseAuth.instance.currentUser;
    return Scaffold(
      appBar: AppBar(
        title: const Text('Página Principal'),
      ),
      body: Padding(
        padding: const EdgeInsets.all(32),
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            const Text(
              'Logado como',
              style: TextStyle(fontSize: 16),
            ),
            const SizedBox(height: 8),
            Text(
              user!.email!,
              style: const TextStyle(fontSize: 20),
            ),
            const SizedBox(height: 40),
            ElevatedButton.icon(
              style: ElevatedButton.styleFrom(
                minimumSize: const Size.fromHeight(50),
              ),
              icon: const Icon(Icons.arrow_back, size: 32),
              label: const Text(
                'Deslogar',
                style: TextStyle(fontSize: 24),
              ),
              onPressed: () => FirebaseAuth.instance.signOut(),
            ),
          ],
        ),
      ),
    );
  }
}

class LoginWidget extends StatefulWidget {
  const LoginWidget({super.key});

  @override
  _LoginWidgetState createState() => _LoginWidgetState();
}

class _LoginWidgetState extends State<LoginWidget> {
  final emailController = TextEditingController();
  final passwordController = TextEditingController();

  @override
  void dispose() {
    emailController.dispose();
    passwordController.dispose();

    super.dispose();
  }

  @override
  Widget build(BuildContext context) => SingleChildScrollView(
        padding: const EdgeInsets.all(16),
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            const SizedBox(height: 40),
            TextField(
              controller: emailController,
              cursorColor: Colors.white,
              textInputAction: TextInputAction.next,
              decoration: const InputDecoration(labelText: 'Email'),
            ),
            const SizedBox(height: 4),
            TextField(
              controller: passwordController,
              textInputAction: TextInputAction.done,
              decoration: const InputDecoration(labelText: 'Senha'),
              obscureText: true,
            ),
            const SizedBox(height: 20),
            ElevatedButton.icon(
              style: ElevatedButton.styleFrom(
                minimumSize: const Size.fromHeight(50),
              ),
              icon: const Icon(Icons.lock_open, size: 32),
              label: const Text(
                'Logar',
                style: TextStyle(fontSize: 24),
              ),
              onPressed: signIn,
            ),
          ],
        ),
      );

  Future signIn() async {
    await FirebaseAuth.instance.signInWithEmailAndPassword(
      email: emailController.text.trim(),
      password: passwordController.text.trim(),
    );
  }
}

Future main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await Firebase.initializeApp();

  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  static final String title = 'Tradeit Auth Prototype';

  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) => MaterialApp(
        debugShowCheckedModeBanner: false,
        title: title,
        theme: ThemeData.dark().copyWith(
          colorScheme: ColorScheme.fromSwatch(primarySwatch: Colors.grey)
              .copyWith(secondary: Colors.green),
        ),
        home: MainPage(),
      );
}

class MainPage extends StatelessWidget {
  const MainPage({super.key});

  @override
  Widget build(BuildContext context) => Scaffold(
        body: StreamBuilder<User?>(
          stream: FirebaseAuth.instance.authStateChanges(),
          builder: (context, snapshot) {
            if (snapshot.hasData) {
              return HomePage();
            } else {
              return LoginWidget();
            }
          },
        ),
      );
}