/// Bottom sheet to add or edit a priced line item.
library;

import 'package:flutter/material.dart';

import '../models/line_item.dart';
import '../utils/money.dart';

Future<LineItem?> showItemEditSheet(BuildContext context, {LineItem? item}) {
  return showModalBottomSheet<LineItem>(
    context: context,
    isScrollControlled: true,
    showDragHandle: true,
    builder: (context) => ItemEditSheet(item: item),
  );
}

class ItemEditSheet extends StatefulWidget {
  const ItemEditSheet({super.key, this.item});

  final LineItem? item;

  @override
  State<ItemEditSheet> createState() => _ItemEditSheetState();
}

class _ItemEditSheetState extends State<ItemEditSheet> {
  late final TextEditingController _nameController;
  late final TextEditingController _priceController;
  String? _error;

  @override
  void initState() {
    super.initState();
    final item = widget.item;
    _nameController = TextEditingController(text: item?.name ?? '');
    _priceController = TextEditingController(
      text: item == null ? '' : item.price.toStringAsFixed(2),
    );
  }

  @override
  void dispose() {
    _nameController.dispose();
    _priceController.dispose();
    super.dispose();
  }

  void _save() {
    final name = _nameController.text.trim();
    final price = tryParsePrice(_priceController.text);
    if (name.isEmpty || price == null) {
      setState(() => _error = 'Enter a product name and a price.');
      return;
    }
    final rounded = roundMoney(price);
    final quantity = widget.item?.quantity;
    Navigator.of(context).pop(
      LineItem(
        id:
            widget.item?.id ??
            'manual-${DateTime.now().microsecondsSinceEpoch}',
        name: name,
        price: rounded,
        quantity: quantity,
        unitPrice: quantity != null && quantity > 0
            ? roundMoney(rounded / quantity)
            : widget.item?.unitPrice,
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    final bottom = MediaQuery.viewInsetsOf(context).bottom;

    return Padding(
      padding: EdgeInsets.fromLTRB(16, 0, 16, 16 + bottom),
      child: Column(
        mainAxisSize: MainAxisSize.min,
        crossAxisAlignment: CrossAxisAlignment.stretch,
        children: [
          Text(
            widget.item == null ? 'Add item' : 'Edit item',
            style: Theme.of(context).textTheme.titleLarge,
          ),
          const SizedBox(height: 16),
          TextField(
            controller: _nameController,
            textCapitalization: TextCapitalization.sentences,
            decoration: const InputDecoration(labelText: 'Product name'),
            autofocus: widget.item == null,
          ),
          const SizedBox(height: 12),
          TextField(
            controller: _priceController,
            keyboardType: const TextInputType.numberWithOptions(decimal: true),
            decoration: const InputDecoration(labelText: 'Price'),
          ),
          if (_error != null) ...[
            const SizedBox(height: 8),
            Text(
              _error!,
              style: TextStyle(color: Theme.of(context).colorScheme.error),
            ),
          ],
          const SizedBox(height: 16),
          FilledButton(onPressed: _save, child: const Text('Save')),
        ],
      ),
    );
  }
}