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

import '../../core/utils/ru_date.dart';
import '../portfolio/providers.dart' show scopesProvider;
import 'data/goals_api.dart';

/// Create/edit form for a goal. Returns the goal to save, or null when cancelled.
class GoalEditDialog extends ConsumerStatefulWidget {
  const GoalEditDialog({super.key, this.initial});

  final Goal? initial;

  @override
  ConsumerState<GoalEditDialog> createState() => _GoalEditDialogState();
}

class _GoalEditDialogState extends ConsumerState<GoalEditDialog> {
  final _formKey = GlobalKey<FormState>();
  late final _name = TextEditingController(text: widget.initial?.name ?? '');
  late final _amount = TextEditingController(
    text: widget.initial?.targetAmount ?? '',
  );
  late final _contribution = TextEditingController(
    text: widget.initial?.monthlyContribution ?? '',
  );
  late final _note = TextEditingController(text: widget.initial?.note ?? '');
  late String _scope = widget.initial?.scope ?? 'all';
  late DateTime? _targetDate = widget.initial?.targetDate;
  late bool _archived = widget.initial?.archived ?? false;

  @override
  void dispose() {
    _name.dispose();
    _amount.dispose();
    _contribution.dispose();
    _note.dispose();
    super.dispose();
  }

  String? _decimalValidator(String? v, {bool required = true}) {
    final text = (v ?? '').trim().replaceAll(',', '.');
    if (text.isEmpty) return required ? 'Обязательное поле' : null;
    return Decimal.tryParse(text) == null ? 'Нужно число' : null;
  }

  static String? _decimal(String text) {
    final normalized = text.trim().replaceAll(',', '.').replaceAll(' ', '');
    if (normalized.isEmpty) return null;
    return Decimal.tryParse(normalized)?.toString();
  }

  @override
  Widget build(BuildContext context) {
    final scopes = ref.watch(scopesProvider).valueOrNull ?? const <ScopeOut>[];

    return AlertDialog(
      title: Text(widget.initial == null ? 'Новая цель' : 'Цель'),
      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<String>(
                  initialValue:
                      scopes.any((s) => s.scope == _scope) || _scope == 'all'
                      ? _scope
                      : 'all',
                  decoration: const InputDecoration(labelText: 'Что считаем'),
                  items: [
                    if (!scopes.any((s) => s.scope == 'all'))
                      const DropdownMenuItem(value: 'all', child: Text('Всё')),
                    for (final s in scopes)
                      DropdownMenuItem(value: s.scope, child: Text(s.name)),
                  ],
                  onChanged: (v) => setState(() => _scope = v ?? 'all'),
                ),
                const SizedBox(height: 12),
                TextFormField(
                  controller: _amount,
                  keyboardType: const TextInputType.numberWithOptions(
                    decimal: true,
                  ),
                  decoration: const InputDecoration(
                    labelText: 'Целевая сумма, ₽',
                  ),
                  validator: _decimalValidator,
                ),
                const SizedBox(height: 12),
                TextFormField(
                  controller: _contribution,
                  keyboardType: const TextInputType.numberWithOptions(
                    decimal: true,
                  ),
                  decoration: const InputDecoration(
                    labelText: 'Ежемесячный взнос, ₽',
                    helperText: 'необязательно',
                  ),
                  validator: (v) => _decimalValidator(v, required: false),
                ),
                const SizedBox(height: 12),
                Row(
                  children: [
                    Expanded(
                      child: Text(
                        _targetDate == null
                            ? 'Целевая дата не задана'
                            : 'Целевая дата: ${ruDate(_targetDate!)}',
                      ),
                    ),
                    TextButton(
                      onPressed: () async {
                        final now = DateTime.now();
                        final picked = await showDatePicker(
                          context: context,
                          initialDate:
                              _targetDate ??
                              DateTime(now.year + 3, now.month, now.day),
                          firstDate: DateTime(now.year - 1),
                          lastDate: DateTime(now.year + 50),
                        );
                        if (picked != null)
                          setState(() => _targetDate = picked);
                      },
                      child: const Text('Выбрать'),
                    ),
                    if (_targetDate != null)
                      IconButton(
                        tooltip: 'Убрать дату',
                        icon: const Icon(Icons.clear),
                        onPressed: () => setState(() => _targetDate = null),
                      ),
                  ],
                ),
                const SizedBox(height: 12),
                TextFormField(
                  controller: _note,
                  decoration: const InputDecoration(labelText: 'Заметка'),
                ),
                if (widget.initial != null)
                  SwitchListTile(
                    contentPadding: EdgeInsets.zero,
                    title: const Text('В архиве'),
                    value: _archived,
                    onChanged: (v) => setState(() => _archived = v),
                  ),
              ],
            ),
          ),
        ),
      ),
      actions: [
        TextButton(
          onPressed: () => Navigator.of(context).pop(),
          child: const Text('Отмена'),
        ),
        FilledButton(
          onPressed: () {
            if (!(_formKey.currentState?.validate() ?? false)) return;
            Navigator.of(context).pop(
              Goal(
                id: widget.initial?.id ?? 0,
                name: _name.text.trim(),
                scope: _scope,
                targetAmount: _decimal(_amount.text) ?? '0',
                currency: widget.initial?.currency ?? 'RUB',
                targetDate: _targetDate,
                monthlyContribution: _decimal(_contribution.text),
                note: _note.text.trim().isEmpty ? null : _note.text.trim(),
                archived: _archived,
              ),
            );
          },
          child: const Text('Сохранить'),
        ),
      ],
    );
  }
}