yubioath-flutter/lib/fido/views/pin_dialog.dart

import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:logging/logging.dart';

import '../../app/logging.dart';
import '../../app/message.dart';
import '../../app/models.dart';
import '../../desktop/models.dart';
import '../../widgets/responsive_dialog.dart';
import '../models.dart';
import '../state.dart';

final _log = Logger('fido.views.pin_dialog');

class FidoPinDialog extends ConsumerStatefulWidget {
  final DevicePath devicePath;
  final FidoState state;
  const FidoPinDialog(this.devicePath, this.state, {super.key});

  @override
  ConsumerState<ConsumerStatefulWidget> createState() => _FidoPinDialogState();
}

class _FidoPinDialogState extends ConsumerState<FidoPinDialog> {
  String _currentPin = '';
  String _newPin = '';
  String _confirmPin = '';
  String? _currentPinError;
  String? _newPinError;
  bool _currentIsWrong = false;
  bool _newIsWrong = false;

  @override
  Widget build(BuildContext context) {
    final hasPin = widget.state.hasPin;
    final isValid = _newPin.isNotEmpty &&
        _newPin == _confirmPin &&
        (!hasPin || _currentPin.isNotEmpty);
    final minPinLength = widget.state.minPinLength;

    return ResponsiveDialog(
      title: Text(hasPin ? 'Change PIN' : 'Set PIN'),
      actions: [
        TextButton(
          onPressed: isValid ? _submit : null,
          child: const Text('Save'),
        ),
      ],
      child: Padding(
        padding: const EdgeInsets.symmetric(horizontal: 18.0),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            if (hasPin) ...[
              const Text(
                  "Enter your current PIN. If you don't know your PIN, you'll need to reset the YubiKey."),
              TextFormField(
                initialValue: _currentPin,
                autofocus: true,
                obscureText: true,
                decoration: InputDecoration(
                  border: const OutlineInputBorder(),
                  labelText: 'Current PIN',
                  errorText: _currentIsWrong ? _currentPinError : null,
                  errorMaxLines: 3,
                  prefixIcon: const Icon(Icons.pin_outlined),
                ),
                onChanged: (value) {
                  setState(() {
                    _currentIsWrong = false;
                    _currentPin = value;
                  });
                },
              ),
            ],
            Text(
                'Enter your new PIN. A PIN must be at least $minPinLength characters long and may contain letters, numbers and special characters.'),
            // TODO: Set max characters based on UTF-8 bytes
            TextFormField(
              initialValue: _newPin,
              autofocus: !hasPin,
              obscureText: true,
              decoration: InputDecoration(
                border: const OutlineInputBorder(),
                labelText: 'New PIN',
                enabled: !hasPin || _currentPin.isNotEmpty,
                errorText: _newIsWrong ? _newPinError : null,
                errorMaxLines: 3,
                prefixIcon: const Icon(Icons.pin_outlined),
              ),
              onChanged: (value) {
                setState(() {
                  _newIsWrong = false;
                  _newPin = value;
                });
              },
            ),
            TextFormField(
              initialValue: _confirmPin,
              obscureText: true,
              decoration: InputDecoration(
                border: const OutlineInputBorder(),
                labelText: 'Confirm PIN',
                prefixIcon: const Icon(Icons.pin_outlined),
                enabled:
                    (!hasPin || _currentPin.isNotEmpty) && _newPin.isNotEmpty,
              ),
              onChanged: (value) {
                setState(() {
                  _confirmPin = value;
                });
              },
              onFieldSubmitted: (_) {
                if (isValid) {
                  _submit();
                }
              },
            ),
          ]
              .map((e) => Padding(
                    padding: const EdgeInsets.symmetric(vertical: 8.0),
                    child: e,
                  ))
              .toList(),
        ),
      ),
    );
  }

  void _submit() async {
    final minPinLength = widget.state.minPinLength;
    final oldPin = _currentPin.isNotEmpty ? _currentPin : null;
    if (_newPin.length < minPinLength) {
      setState(() {
        _newPinError = 'New PIN must be at least $minPinLength characters';
        _newIsWrong = true;
      });
      return;
    }
    try {
      final result = await ref
          .read(fidoStateProvider(widget.devicePath).notifier)
          .setPin(_newPin, oldPin: oldPin);
      result.when(success: () {
        Navigator.of(context).pop(true);
        showMessage(context, 'PIN set');
      }, failed: (retries, authBlocked) {
        setState(() {
          if (authBlocked) {
            _currentPinError =
                'PIN has been blocked until the YubiKey is removed and reinserted';
            _currentIsWrong = true;
          } else {
            _currentPinError = 'Wrong PIN ($retries tries remaining)';
            _currentIsWrong = true;
          }
        });
      });
    } catch (e) {
      _log.error('Failed to set PIN', e);
      final String errorMessage;
      // TODO: Make this cleaner than importing desktop specific RpcError.
      if (e is RpcError) {
        errorMessage = e.message;
      } else {
        errorMessage = e.toString();
      }
      showMessage(
        context,
        'Failed to set PIN: $errorMessage',
        duration: const Duration(seconds: 4),
      );
    }
  }
}