import 'package:flutter/material.dart';
import '../main.dart';
import 'home_screen.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 _tokenCtrl = TextEditingController();
  bool _loading = false;
  String? _error;

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

    final url = _serverCtrl.text.trim();
    final token = _tokenCtrl.text.trim();

    try {
      apiService.configure(url, '');
      final valid = await apiService.verifyToken(token);
      if (!valid) {
        setState(() { _error = '令牌无效'; _loading = false; });
        return;
      }
      apiService.configure(url, token);
      await settings.setServerUrl(url);
      await settings.setToken(token);
      await apiService.registerDevice('Android');
      if (mounted) {
        Navigator.of(context).pushReplacement(
          MaterialPageRoute(builder: (_) => 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: '服务器地址',
                    hintText: 'http://服务器IP:3000',
                    prefixIcon: Icon(Icons.dns_outlined),
                    border: OutlineInputBorder(),
                  ),
                ),
                const SizedBox(height: 16),
                TextField(
                  controller: _tokenCtrl,
                  obscureText: true,
                  decoration: const InputDecoration(
                    labelText: '访问令牌',
                    prefixIcon: Icon(Icons.key),
                    border: OutlineInputBorder(),
                  ),
                  onSubmitted: (_) => _connect(),
                ),
                if (_error != null) ...[
                  const SizedBox(height: 12),
                  Text(_error!, style: TextStyle(color: colors.error)),
                ],
                const SizedBox(height: 24),
                SizedBox(
                  width: double.infinity,
                  child: FilledButton(
                    onPressed: _loading ? null : _connect,
                    child: _loading
                        ? const SizedBox(height: 20, width: 20, child: CircularProgressIndicator(strokeWidth: 2))
                        : const Text('连接'),
                  ),
                ),
              ],
            ),
          ),
        ),
      ),
    );
  }
}