import 'package:flutter/material.dart';

import '../../../routing/app_routes.dart';
import '../login_controller.dart';
import 'login_error_banner.dart';
import 'login_form_parts.dart';

/// White Card hosting the login form (heading, two text fields, error
/// banner, submit button). Submitting calls [controller.submit] and signals
/// success via [onSuccess].
class LoginCard extends StatefulWidget {
  final LoginController controller;
  final VoidCallback onSuccess;

  const LoginCard({
    required this.controller,
    required this.onSuccess,
    super.key,
  });

  @override
  State<LoginCard> createState() => _LoginCardState();
}

class _LoginCardState extends State<LoginCard> {
  final _formKey = GlobalKey<FormState>();
  final _usernameController = TextEditingController();
  final _passwordController = TextEditingController();
  final _passwordFocus = FocusNode();

  @override
  void initState() {
    super.initState();
    widget.controller.addListener(_onControllerChange);
  }

  @override
  void dispose() {
    widget.controller.removeListener(_onControllerChange);
    _usernameController.dispose();
    _passwordController.dispose();
    _passwordFocus.dispose();
    super.dispose();
  }

  void _onControllerChange() {
    if (mounted) setState(() {});
  }

  String? _required(String? value) =>
      (value ?? '').trim().isEmpty ? 'Eingabe erforderlich' : null;

  Future<void> _submit() async {
    if (widget.controller.loading) return;
    if (!(_formKey.currentState?.validate() ?? false)) return;
    final result = await widget.controller.submit(
      _usernameController.text,
      _passwordController.text,
    );
    if (!mounted) return;
    switch (result) {
      case LoginResult.success:
        widget.onSuccess();
      case LoginResult.nextcloudLoginRequired:
        // 2FA (oder abweichendes NC-Passwort): Anmeldung im Browser über den
        // Login Flow v2 abschließen; ohne Erfolg wird der Login zurückgerollt.
        final ok = await AppRoutes.openNextcloudLoginFlow(context);
        if (!mounted) return;
        if (ok) {
          widget.onSuccess();
        } else {
          await widget.controller.abortNextcloudLogin();
        }
      case LoginResult.failure:
        break;
    }
  }

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final loading = widget.controller.loading;
    return Form(
      key: _formKey,
      child: LoginCardFrame(
        title: 'Anmelden',
        hint: 'Melde dich mit deinen Marianum-Zugangsdaten an.',
        children: [
          TextFormField(
            key: const Key('login-username-field'),
            controller: _usernameController,
            enabled: !loading,
            validator: _required,
            autocorrect: false,
            textInputAction: TextInputAction.next,
            onFieldSubmitted: (_) => _passwordFocus.requestFocus(),
            decoration: loginInputDecoration(
              theme,
              'Nutzername',
              Icons.person_outline,
            ),
          ),
          const SizedBox(height: 12),
          TextFormField(
            key: const Key('login-password-field'),
            controller: _passwordController,
            focusNode: _passwordFocus,
            enabled: !loading,
            validator: _required,
            obscureText: true,
            obscuringCharacter: '•',
            autocorrect: false,
            enableSuggestions: false,
            keyboardType: TextInputType.visiblePassword,
            textInputAction: TextInputAction.done,
            onFieldSubmitted: (_) => _submit(),
            decoration: loginInputDecoration(
              theme,
              'Passwort',
              Icons.lock_outline,
            ),
          ),
          LoginErrorBanner(
            message: widget.controller.errorMessage,
            details: widget.controller.errorDetails,
          ),
          const SizedBox(height: 20),
          LoginSubmitButton(
            key: const Key('login-submit-button'),
            label: 'Anmelden',
            loading: loading,
            onPressed: _submit,
          ),
        ],
      ),
    );
  }
}