import 'package:flutter/material.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'package:http/http.dart' as http;
import 'dart:convert';
import 'mainpage.dart';
import 'package:flutter_dotenv/flutter_dotenv.dart';
import 'config.dart';

Future<void> main() async {
  await dotenv.load();
  runApp(const MyApp());
}

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

  @override
  Widget build(BuildContext context) {
    return FutureBuilder<SharedPreferences>(
      future: SharedPreferences.getInstance(),
      builder: (context, snapshot) {
        if (!snapshot.hasData) {
          return const CircularProgressIndicator();
        }
        final prefs = snapshot.data!;
        final jwt = prefs.getString('jwt');
        return MaterialApp(
          title: 'Litecloud alpha',
          theme: ThemeData(
            colorScheme: ColorScheme.fromSeed(
                seedColor: const Color.fromARGB(255, 72, 4, 117)),
            useMaterial3: true,
          ),
          home: jwt != null ? const MainPage() : const AuthScreen(),
        );
      },
    );
  }
}

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

  @override
  State<AuthScreen> createState() => _AuthScreenState();
}

class _AuthScreenState extends State<AuthScreen> {
  bool _isLogin = true;
  final _emailController = TextEditingController();
  final _passwordController = TextEditingController();
  final _confirmController = TextEditingController();
  bool _loading = false;
  String? _error;

  void _toggleAuthMode() {
    setState(() {
      _isLogin = !_isLogin;
      _error = null;
    });
  }

  Future<void> _submit() async {
    setState(() {
      _loading = true;
      _error = null;
    });

    final email = _emailController.text.trim();
    final password = _passwordController.text.trim();

    if (!_isLogin && password != _confirmController.text.trim()) {
      setState(() {
        _error = "Le password non coincidono";
        _loading = false;
      });
      return;
    }

    final url =
        Uri.parse('${Config.apiUrl}/${_isLogin ? "login" : "register"}');

    final body = jsonEncode({
      "username": email,
      "password": password,
    });

    try {
      final response = await http.post(
        url,
        headers: {'Content-Type': 'application/json'},
        body: body,
      );

      if (response.statusCode == 200 || response.statusCode == 201) {
        final data = jsonDecode(response.body);
        final token = data['token'];
        final prefs = await SharedPreferences.getInstance();
        await prefs.setString('jwt', token);

        if (mounted) {
          Navigator.of(context).pushReplacement(
            MaterialPageRoute(builder: (_) => const MainPage()),
          );
        }
      } else {
        setState(() {
          _error = "Credenziali non valide";
        });
      }
    } catch (e) {
      setState(() {
        _error = "Errore di rete";
      });
    } finally {
      setState(() {
        _loading = false;
      });
    }
  }

  @override
  Widget build(BuildContext context) {
    final deviceSize = MediaQuery.of(context).size;

    return Scaffold(
      body: Container(
        width: deviceSize.width,
        height: deviceSize.height,
        decoration: const BoxDecoration(
          gradient: LinearGradient(
            colors: [Colors.purple, Color.fromARGB(255, 72, 4, 117)],
            begin: Alignment.topLeft,
            end: Alignment.bottomRight,
          ),
        ),
        child: SafeArea(
          child: SingleChildScrollView(
            child: Padding(
              padding: const EdgeInsets.all(16.0),
              child: Column(
                mainAxisAlignment: MainAxisAlignment.center,
                crossAxisAlignment: CrossAxisAlignment.stretch,
                children: [
                  const SizedBox(height: 60),
                  // Logo and tagline
                  Container(
                    margin: const EdgeInsets.only(bottom: 40.0),
                    child: Column(
                      children: [
                        Text(
                          'Litecloud',
                          style: TextStyle(
                            fontSize: 42,
                            fontWeight: FontWeight.bold,
                            color: Theme.of(context).colorScheme.onPrimary,
                          ),
                        ),
                        const SizedBox(height: 8),
                        Text(
                          'Rust based cloud storage',
                          style: TextStyle(
                            fontSize: 16,
                            color: Theme.of(context).colorScheme.onPrimary,
                          ),
                        ),
                        const SizedBox(height: 8),
                        Text(
                          'Version 0.0.1 pre-alpha',
                          style: TextStyle(
                            fontSize: 8,
                            color: Theme.of(context).colorScheme.onPrimary,
                          ),
                        ),
                      ],
                    ),
                  ),
                  // Auth card
                  Card(
                    margin: const EdgeInsets.symmetric(horizontal: 600.0),
                    elevation: 8.0,
                    shape: RoundedRectangleBorder(
                      borderRadius: BorderRadius.circular(16.0),
                    ),
                    child: Padding(
                      padding: const EdgeInsets.all(16.0),
                      child: Column(
                        children: [
                          Text(
                            _isLogin ? 'Login' : 'Register',
                            style: Theme.of(context).textTheme.headlineMedium,
                          ),
                          const SizedBox(height: 40),
                          TextFormField(
                            controller: _emailController,
                            decoration: const InputDecoration(
                              labelText: 'Username',
                              prefixIcon: Icon(Icons.person),
                              border: OutlineInputBorder(),
                            ),
                            keyboardType: TextInputType.emailAddress,
                          ),
                          const SizedBox(height: 16),
                          TextFormField(
                            controller: _passwordController,
                            decoration: const InputDecoration(
                              labelText: 'Password',
                              prefixIcon: Icon(Icons.lock),
                              border: OutlineInputBorder(),
                            ),
                            obscureText: true,
                          ),
                          if (!_isLogin) const SizedBox(height: 16),
                          if (!_isLogin)
                            TextFormField(
                              controller: _confirmController,
                              decoration: const InputDecoration(
                                labelText: 'Confirm Password',
                                prefixIcon: Icon(Icons.lock),
                                border: OutlineInputBorder(),
                              ),
                              obscureText: true,
                            ),
                          const SizedBox(height: 24),
                          FilledButton(
                            onPressed: _loading ? null : _submit,
                            style: FilledButton.styleFrom(
                              minimumSize: const Size(double.infinity, 50),
                            ),
                            child: _loading
                                ? const CircularProgressIndicator()
                                : Text(
                                    _isLogin ? 'LOGIN' : 'REGISTER',
                                    style: const TextStyle(fontSize: 16),
                                  ),
                          ),
                          if (_error != null)
                            Padding(
                              padding: const EdgeInsets.only(top: 8.0),
                              child: Text(_error!,
                                  style: const TextStyle(color: Colors.red)),
                            ),
                          const SizedBox(height: 12),
                          TextButton(
                            onPressed: _toggleAuthMode,
                            child: Text(
                              _isLogin
                                  ? 'Create new account'
                                  : 'I already have an account',
                            ),
                          ),
                        ],
                      ),
                    ),
                  ),
                ],
              ),
            ),
          ),
        ),
      ),
    );
  }
}