// Version: 4.0 - 簡素製品マスタ画面（サンプルデータ固定）
// ※ データベース連携なし：動作保証版
import 'package:flutter/material.dart';

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

  @override
  State<ProductMasterScreen> createState() => _ProductMasterScreenState();
}

class _ProductMasterScreenState extends State<ProductMasterScreen> {
  List<Map<String, dynamic>> _products = [];

  @override
  void initState() {
    super.initState();
    // サンプルデータを初期化
    _products = [
      {'product_code': 'TEST001', 'name': 'サンプル商品 A', 'unit_price': 1000.0, 'quantity': 50},
      {'product_code': 'TEST002', 'name': 'サンプル商品 B', 'unit_price': 2500.0, 'quantity': 30},
      {'product_code': 'TEST003', 'name': 'サンプル商品 C', 'unit_price': 5000.0, 'quantity': 20},
    ];
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('/M0. 製品マスタ')),
      body: ListView.builder(
        padding: const EdgeInsets.all(8),
        itemCount: _products.length,
        itemBuilder: (context, index) {
          final product = _products[index];
          return Card(
            margin: EdgeInsets.zero,
            clipBehavior: Clip.antiAlias,
            child: ListTile(
              leading: CircleAvatar(
                backgroundColor: Colors.blue.shade100,
                child: Text(product['product_code'] ?? '-', style: const TextStyle(fontWeight: FontWeight.bold)),
              ),
              title: Text(product['name'] ?? '未入力'),
              subtitle: Column(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  if (product['unit_price'] != null) Text('単価：${product['unit_price']}円', style: const TextStyle(fontSize: 12)),
                  if (product['quantity'] != null) Text('数量：${product['quantity']}', style: const TextStyle(fontSize: 12)),
                ],
              ),
            ),
          );
        },
      ),
      floatingActionButton: FloatingActionButton.extended(
        icon: const Icon(Icons.add),
        label: const Text('新規登録'),
        onPressed: () {
          setState(() {
            _products = [..._products, {'product_code': 'TEST00${_products.length + 1}', 'name': '新商品', 'unit_price': 0.0, 'quantity': 0}];
          });
          ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('登録完了')));
        },
      ),
    );
  }
}