import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:go_router/go_router.dart';

import '../../core/providers.dart';
import '../../widgets/ui.dart';
import 'shop_picker.dart';
import '../../core/theme.dart';

const _maxW = 640.0;

class UserFormScreen extends ConsumerStatefulWidget {
  const UserFormScreen({super.key});

  @override
  ConsumerState<UserFormScreen> createState() => _UserFormScreenState();
}

class _UserFormScreenState extends ConsumerState<UserFormScreen> {
  final _name = TextEditingController();
  final _phone = TextEditingController();
  final _pass = TextEditingController();
  final _shops = <int>{};
  bool _busy = false;
  String? _error;

  @override
  void dispose() {
    _name.dispose();
    _phone.dispose();
    _pass.dispose();
    super.dispose();
  }

  bool get _ready => _name.text.trim().length >= 3 && _pass.text.length >= 8;

  Future<void> _create() async {
    setState(() {
      _busy = true;
      _error = null;
    });
    try {
      await mutate(
        ref,
        () => ref
            .read(apiProvider)
            .createUser(
              username: _name.text,
              phone: _phone.text.trim().isEmpty ? null : _phone.text,
              password: _pass.text,
              shopIds: _shops.toList(),
            ),
      );
      if (!mounted) return;
      context.pop();
      toast(context, 'User created');
    } catch (e) {
      if (mounted) setState(() => _error = errText(e));
    } finally {
      if (mounted) setState(() => _busy = false);
    }
  }

  @override
  Widget build(BuildContext context) {
    final shops = ref.watch(activeShopsProvider);
    return Scaffold(
      body: SafeArea(
        child: Column(
          children: [
            const ScreenHeader(title: 'Add user', back: true, maxWidth: _maxW),
            Expanded(
              child: PageList(
                maxWidth: _maxW,
                top: S.s8,
                children: [
                  SrsField(
                    controller: _name,
                    label: 'Username',
                    hint: 'e.g. kzk.staff',
                    helper:
                        'Letters, numbers, dots, dashes and underscores. Used to sign in.',
                    onChanged: (_) => setState(() => _error = null),
                  ),
                  const SizedBox(height: S.s18),
                  SrsField(
                    controller: _phone,
                    label: 'Phone (optional)',
                    hint: '90000 12345',
                    prefix: '+91  ',
                    keyboard: TextInputType.phone,
                    formatters: [
                      FilteringTextInputFormatter.allow(RegExp(r'[0-9 ]')),
                      LengthLimitingTextInputFormatter(12),
                    ],
                    onChanged: (_) => setState(() => _error = null),
                  ),
                  const SizedBox(height: S.s18),
                  SrsField(
                    controller: _pass,
                    label: 'Password',
                    hint: 'Enter password',
                    password: true,
                    helper: 'At least 8 characters.',
                    onChanged: (_) => setState(() => _error = null),
                  ),
                  const SectionTitle('Shop access'),
                  asyncView(
                    shops,
                    (list) => ShopPicker(
                      shops: list,
                      selected: _shops,
                      onToggle: (id) => setState(
                        () => _shops.contains(id)
                            ? _shops.remove(id)
                            : _shops.add(id),
                      ),
                    ),
                  ),
                  if (_error != null) ...[
                    const SizedBox(height: S.s8),
                    ErrorLine(_error!),
                  ],
                  const SizedBox(height: S.s22),
                  BigButton(
                    'Create user',
                    loading: _busy,
                    onPressed: _ready ? _create : null,
                  ),
                ],
              ),
            ),
          ],
        ),
      ),
    );
  }
}