// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0

import 'package:amplify_flutter/amplify_flutter.dart';
import 'package:flutter/material.dart';
import 'package:go_router/go_router.dart';

class _UserAttributeController {
  factory _UserAttributeController({String? keyValue}) {
    return _UserAttributeController._(
      TextEditingController(text: keyValue),
      TextEditingController(),
    );
  }

  const _UserAttributeController._(this.keyController, this.valueController);

  final TextEditingController keyController;
  final TextEditingController valueController;
}

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

  @override
  State<UpdateUserAttributesScreen> createState() =>
      _UpdateUserAttributesScreenState();
}

class _UpdateUserAttributesScreenState
    extends State<UpdateUserAttributesScreen> {
  final List<_UserAttributeController> _userAttributeControllers = [
    _UserAttributeController(keyValue: 'name'),
    _UserAttributeController(keyValue: 'preferred_username'),
  ];

  final _formKey = GlobalKey<FormState>();

  void _showSuccess(String message) {
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(
        backgroundColor: Colors.green[800],
        content: Text(message),
      ),
    );
  }

  void _showInfo(String message) {
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(
        backgroundColor: Colors.blue[800],
        content: Text(message),
      ),
    );
  }

  void _showError(String message) {
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(
        backgroundColor: Colors.red[900],
        content: Text(message),
      ),
    );
  }

  Future<void> _updateAttributes() async {
    if (!_formKey.currentState!.validate()) {
      return;
    }
    try {
      final attributes = _userAttributeControllers
          .map(
            (controller) => AuthUserAttribute(
              userAttributeKey: CognitoUserAttributeKey.parse(
                controller.keyController.text,
              ),
              value: controller.valueController.text,
            ),
          )
          .toList();
      final res = await Amplify.Auth.updateUserAttributes(
        attributes: attributes,
      );
      final attributesWithConfirmation = res.entries
          .where(
            (element) =>
                element.value.nextStep.updateAttributeStep ==
                AuthUpdateAttributeStep.confirmAttributeWithCode,
          )
          .map((element) => element.key)
          .toList();
      if (attributesWithConfirmation.isNotEmpty) {
        _showInfo(
          'Confirmation Code sent for attributes: '
          '$attributesWithConfirmation',
        );
      } else {
        _showSuccess('Attributes Updated Successfully');
      }
      if (mounted) {
        context.go('/');
      }
    } on Exception catch (e) {
      _showError(e.toString());
    }
  }

  void _addAttribute() {
    setState(() {
      _userAttributeControllers.add(_UserAttributeController());
    });
  }

  void _removeAttribute(_UserAttributeController controller) {
    setState(() {
      _userAttributeControllers.remove(controller);
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Update Attributes'),
      ),
      body: Padding(
        padding: const EdgeInsets.all(8),
        child: Form(
          key: _formKey,
          child: ListView(
            children: [
              ..._userAttributeControllers.map((element) {
                return Card(
                  child: Stack(
                    children: [
                      Padding(
                        padding: const EdgeInsets.only(
                          left: 16,
                          bottom: 24,
                          right: 16,
                        ),
                        child: Column(
                          children: [
                            TextFormField(
                              controller: element.keyController,
                              decoration: const InputDecoration(
                                labelText: 'Attribute Name',
                              ),
                              validator: (value) {
                                if (value == null) {
                                  return 'An Attribute name is required.';
                                }
                                return null;
                              },
                            ),
                            TextFormField(
                              controller: element.valueController,
                              decoration: const InputDecoration(
                                labelText: 'Attribute Value',
                              ),
                              validator: (value) {
                                if (value == null) {
                                  return 'An Attribute value is required.';
                                }
                                return null;
                              },
                            ),
                          ],
                        ),
                      ),
                      Row(
                        mainAxisAlignment: MainAxisAlignment.end,
                        children: [
                          IconButton(
                            padding: EdgeInsets.zero,
                            icon: const Icon(
                              Icons.close,
                              size: 18,
                            ),
                            onPressed: () => _removeAttribute(element),
                          ),
                        ],
                      ),
                    ],
                  ),
                );
              }),
              const SizedBox(height: 12),
              ElevatedButton(
                onPressed: _updateAttributes,
                child: const Text('Update Attributes'),
              ),
              TextButton(
                onPressed: _addAttribute,
                child: const Text('Add New Attribute'),
              ),
            ],
          ),
        ),
      ),
    );
  }
}