import 'package:dio/dio.dart';
import 'package:fintracker_api/fintracker_api.dart';
import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';

import '../../core/api/api_client.dart';
import '../../core/auth/auth_controller.dart';
import 'providers.dart';

/// The brokers whose accounts are created by hand: T-Invest accounts come from the sync.
const _brokerChoices = [
  (Broker.sber, 'Сбер'),
  (Broker.vtb, 'ВТБ'),
  (Broker.other, 'Другой (CSV)'),
];

/// Maps the import contract's broker key (`sber | vtb | csv`) onto a creatable broker.
Broker? brokerFromImportKey(String? key) => switch (key) {
  'sber' => Broker.sber,
  'vtb' => Broker.vtb,
  'csv' => Broker.other,
  _ => null,
};

/// Asks for the details of a broker account and creates it. Returns the new account, or null
/// when cancelled or when the server refused (the reason is shown in the dialog).
Future<AccountOut?> showAccountCreateDialog(
  BuildContext context, {
  Broker? broker,
  String? sourceId,
  String? name,
}) => showDialog<AccountOut>(
  context: context,
  builder: (_) =>
      _AccountCreateDialog(broker: broker, sourceId: sourceId, name: name),
);

class _AccountCreateDialog extends ConsumerStatefulWidget {
  const _AccountCreateDialog({this.broker, this.sourceId, this.name});

  final Broker? broker;
  final String? sourceId;
  final String? name;

  @override
  ConsumerState<_AccountCreateDialog> createState() =>
      _AccountCreateDialogState();
}

class _AccountCreateDialogState extends ConsumerState<_AccountCreateDialog> {
  final _formKey = GlobalKey<FormState>();
  late final _name = TextEditingController(text: widget.name ?? '');
  late final _sourceId = TextEditingController(text: widget.sourceId ?? '');
  final _currency = TextEditingController(text: 'RUB');
  late Broker _broker = widget.broker ?? Broker.sber;
  bool _saving = false;
  String? _error;

  @override
  void dispose() {
    _name.dispose();
    _sourceId.dispose();
    _currency.dispose();
    super.dispose();
  }

  Future<void> _save() async {
    if (!(_formKey.currentState?.validate() ?? false)) return;
    setState(() {
      _saving = true;
      _error = null;
    });
    try {
      final r = await ref
          .read(apiProvider)
          .getAccountsApi()
          .accountsCreate(
            accountCreate: AccountCreate(
              name: _name.text.trim(),
              broker: _broker,
              sourceId: _sourceId.text.trim(),
              currency: _currency.text.trim().toUpperCase(),
            ),
          );
      ref.invalidate(accountsProvider);
      if (mounted) Navigator.of(context).pop(r.data);
    } on DioException catch (e) {
      if (mounted) {
        setState(() {
          _saving = false;
          _error = problemMessage(e);
        });
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    return AlertDialog(
      title: const Text('Новый брокерский счёт'),
      content: SizedBox(
        width: 420,
        child: Form(
          key: _formKey,
          child: SingleChildScrollView(
            child: Column(
              mainAxisSize: MainAxisSize.min,
              children: [
                TextFormField(
                  controller: _name,
                  decoration: const InputDecoration(labelText: 'Название'),
                  validator: (v) =>
                      (v ?? '').trim().isEmpty ? 'Обязательное поле' : null,
                ),
                const SizedBox(height: 12),
                DropdownButtonFormField<Broker>(
                  initialValue: _broker,
                  decoration: const InputDecoration(labelText: 'Брокер'),
                  items: [
                    for (final (b, label) in _brokerChoices)
                      DropdownMenuItem(value: b, child: Text(label)),
                  ],
                  onChanged: (b) => setState(() => _broker = b ?? _broker),
                ),
                const SizedBox(height: 12),
                TextFormField(
                  controller: _sourceId,
                  decoration: const InputDecoration(
                    labelText: 'Номер договора',
                    helperText: 'Как напечатан в отчёте брокера — по нему импорт находит счёт',
                    helperMaxLines: 2,
                  ),
                  validator: (v) =>
                      (v ?? '').trim().isEmpty ? 'Обязательное поле' : null,
                ),
                const SizedBox(height: 12),
                TextFormField(
                  controller: _currency,
                  textCapitalization: TextCapitalization.characters,
                  decoration: const InputDecoration(labelText: 'Валюта'),
                  validator: (v) => (v ?? '').trim().length == 3
                      ? null
                      : 'Три буквы, например RUB',
                ),
                if (_error != null) ...[
                  const SizedBox(height: 12),
                  Text(
                    _error!,
                    style: TextStyle(
                      color: Theme.of(context).colorScheme.error,
                    ),
                  ),
                ],
              ],
            ),
          ),
        ),
      ),
      actions: [
        TextButton(
          onPressed: _saving ? null : () => Navigator.of(context).pop(),
          child: const Text('Отмена'),
        ),
        FilledButton(
          onPressed: _saving ? null : _save,
          child: const Text('Создать'),
        ),
      ],
    );
  }
}