import 'package:flutter/material.dart';
import '../main.dart';

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

  @override
  State<LoginScreen> createState() => _LoginScreenState();
}

class _LoginScreenState extends State<LoginScreen> {
  final _serverCtrl = TextEditingController(text: 'http://192.168.1.100:3000');
  final _userCtrl = TextEditingController();
  final _passCtrl = TextEditingController();
  bool _loading = false;
  String? _error;

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

    final url = _serverCtrl.text.trim();
    final user = _userCtrl.text.trim();
    final pass = _passCtrl.text.trim();

    try {
      apiService.configure(url, '');
      final token = register
          ? await apiService.register(user, pass)
          : await apiService.login(user, pass);
      apiService.configure(url, token);
      await settings.setServerUrl(url);
      await settings.setToken(token);
      await apiService.registerDevice('Android');
      if (mounted) {
        Navigator.of(context).pushReplacement(
          MaterialPageRoute(builder: (_) => const HomeScreen()),
        );
      }
    } catch (e) {
      setState(() => _error = e.toString().replaceFirst('Exception: ', ''));
    }
    setState(() => _loading = false);
  }

  @override
  Widget build(BuildContext context) {
    final colors = Theme.of(context).colorScheme;
    return Scaffold(
      body: Center(
        child: SingleChildScrollView(
          padding: const EdgeInsets.all(24),
          child: ConstrainedBox(
            constraints: const BoxConstraints(maxWidth: 400),
            child: Column(
              mainAxisSize: MainAxisSize.min,
              children: [
                Icon(Icons.sms_outlined, size: 64, color: colors.primary),
                const SizedBox(height: 16),
                Text('SMS Monitor', style: Theme.of(context).textTheme.headlineMedium),
                const SizedBox(height: 32),
                TextField(
                  controller: _serverCtrl,
                  decoration: const InputDecoration(
                    labelText: 'Server URL',
                    hintText: 'http://your-server:3000',
                    prefixIcon: Icon(Icons.dns_outlined),
                    border: OutlineInputBorder(),
                  ),
                ),
                const SizedBox(height: 16),
                TextField(
                  controller: _userCtrl,
                  decoration: const InputDecoration(
                    labelText: 'Username',
                    prefixIcon: Icon(Icons.person_outline),
                    border: OutlineInputBorder(),
                  ),
                ),
                const SizedBox(height: 16),
                TextField(
                  controller: _passCtrl,
                  obscureText: true,
                  decoration: const InputDecoration(
                    labelText: 'Password',
                    prefixIcon: Icon(Icons.lock_outline),
                    border: OutlineInputBorder(),
                  ),
                  onSubmitted: (_) => _submit(false),
                ),
                if (_error != null) ...[
                  const SizedBox(height: 12),
                  Text(_error!, style: TextStyle(color: colors.error)),
                ],
                const SizedBox(height: 24),
                Row(
                  children: [
                    Expanded(
                      child: OutlinedButton(
                        onPressed: _loading ? null : () => _submit(true),
                        child: const Text('Register'),
                      ),
                    ),
                    const SizedBox(width: 16),
                    Expanded(
                      child: FilledButton(
                        onPressed: _loading ? null : () => _submit(false),
                        child: _loading
                            ? const SizedBox(height: 20, width: 20, child: CircularProgressIndicator(strokeWidth: 2))
                            : const Text('Sign In'),
                      ),
                    ),
                  ],
                ),
              ],
            ),
          ),
        ),
      ),
    );
  }
}