import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:go_router/go_router.dart';
import 'package:pyramid/features/auth/login_notifier.dart';

class ServerPage extends ConsumerStatefulWidget {
  const ServerPage({super.key});

  @override
  ConsumerState<ServerPage> createState() => _ServerPageState();
}

class _ServerPageState extends ConsumerState<ServerPage> {
  final _formKey = GlobalKey<FormState>();
  final _ctrl = TextEditingController(text: 'matrix.org');
  bool _loading = false;
  String? _error;

  @override
  void initState() {
    super.initState();
    ref.read(homeserverProvider.future).then((saved) {
      if (saved != null && mounted) {
        _ctrl.text = saved.replaceAll(RegExp(r'^https?://'), '');
      }
    });
  }

  @override
  void dispose() {
    _ctrl.dispose();
    super.dispose();
  }

  Future<void> _continue() async {
    if (!_formKey.currentState!.validate()) return;
    setState(() { _loading = true; _error = null; });

    final input = _ctrl.text.trim().replaceAll(RegExp(r'^https?://'), '');
    try {
      await saveHomeserver(input);
      if (mounted) context.go('/login');
    } catch (e) {
      setState(() => _error = e.toString());
    } finally {
      if (mounted) setState(() => _loading = false);
    }
  }

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);

    return Scaffold(
      body: Center(
        child: ConstrainedBox(
          constraints: const BoxConstraints(maxWidth: 400),
          child: Padding(
            padding: const EdgeInsets.all(24),
            child: Form(
              key: _formKey,
              child: Column(
                mainAxisSize: MainAxisSize.min,
                crossAxisAlignment: CrossAxisAlignment.stretch,
                children: [
                  Icon(
                    Icons.change_history_rounded,
                    size: 72,
                    color: theme.colorScheme.primary,
                  ),
                  const SizedBox(height: 8),
                  Text(
                    'Pyramid',
                    textAlign: TextAlign.center,
                    style: theme.textTheme.headlineMedium
                        ?.copyWith(fontWeight: FontWeight.bold),
                  ),
                  const SizedBox(height: 32),
                  Text(
                    'Server',
                    style: theme.textTheme.titleMedium,
                  ),
                  const SizedBox(height: 8),
                  TextFormField(
                    controller: _ctrl,
                    decoration: const InputDecoration(
                      hintText: 'matrix.org',
                      prefixText: 'https://',
                      prefixIcon: Icon(Icons.dns_outlined),
                      border: OutlineInputBorder(),
                    ),
                    keyboardType: TextInputType.url,
                    validator: (v) {
                      if (v == null || v.trim().isEmpty) {
                        return 'Server-Adresse eingeben';
                      }
                      return null;
                    },
                    onFieldSubmitted: (_) => _continue(),
                  ),
                  if (_error != null) ...[
                    const SizedBox(height: 12),
                    Text(
                      _error!,
                      style: TextStyle(color: theme.colorScheme.error),
                      textAlign: TextAlign.center,
                    ),
                  ],
                  const SizedBox(height: 24),
                  FilledButton(
                    onPressed: _loading ? null : _continue,
                    child: _loading
                        ? const SizedBox(
                            height: 20,
                            width: 20,
                            child: CircularProgressIndicator(strokeWidth: 2),
                          )
                        : const Text('Weiter'),
                  ),
                ],
              ),
            ),
          ),
        ),
      ),
    );
  }
}