// Version: 1.6 - 在庫管理画面（簡易実装）
import 'package:flutter/material.dart';

/// 在庫管理画面
class InventoryMasterScreen extends StatefulWidget {
  const InventoryMasterScreen({super.key});

  @override
  State<InventoryMasterScreen> createState() => _InventoryMasterScreenState();
}

class _InventoryMasterScreenState extends State<InventoryMasterScreen> {
  String _productName = ''; // 商品名
  int _stock = 0; // 在庫数
  int _minStock = 10; // 再仕入れ水準
  String? _supplierName; // 供給元

  @override
  void initState() {
    super.initState();
    // TODO: DatabaseHelper.instance.getInventory() を使用
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('在庫管理')),
      body: SingleChildScrollView(
        child: Padding(
          padding: const EdgeInsets.all(16),
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.stretch,
            children: [
              // 商品名入力
              TextField(
                decoration: const InputDecoration(hintText: '商品名', border: OutlineInputBorder()),
                onChanged: (value) => setState(() => _productName = value),
              ),

              const SizedBox(height: 16),

              // 在庫数入力
              TextField(
                decoration: const InputDecoration(hintText: '在庫数', border: OutlineInputBorder()),
                keyboardType: TextInputType.number,
                onChanged: (value) => setState(() => _stock = int.tryParse(value) ?? 0),
              ),

              const SizedBox(height: 16),

              // 再仕入れ水準入力
              TextField(
                decoration: const InputDecoration(hintText: '再仕入れ水準', border: OutlineInputBorder()),
                keyboardType: TextInputType.number,
                onChanged: (value) => setState(() => _minStock = int.tryParse(value) ?? 10),
              ),

              const SizedBox(height: 16),

              // 供給元入力（簡易）
              TextField(
                decoration: const InputDecoration(hintText: '供給元', border: OutlineInputBorder()),
                onChanged: (value) => setState(() => _supplierName = value.isNotEmpty ? value : null),
              ),

              const SizedBox(height: 16),

              // 在庫表示エリア（簡易）
              Card(
                child: ListTile(
                  contentPadding: EdgeInsets.zero,
                  title: const Text('現在の在庫'),
                  subtitle: Text('${_stock}個', style: const TextStyle(fontSize: 18)),
                  trailing: _stock <= _minStock ? const Icon(Icons.warning, color: Colors.orange) : const SizedBox(),
                ),
              ),

              const SizedBox(height: 16),

              // 保存ボタン（簡易）
              ElevatedButton(
                onPressed: () {
                  if (mounted) {
                    ScaffoldMessenger.of(context).showSnackBar(
                      const SnackBar(content: Text('在庫データを更新しました')),
                    );
                  }
                },
                style: ElevatedButton.styleFrom(padding: const EdgeInsets.symmetric(vertical: 12)),
                child: const Text('更新'),
              ),

            ],
          ),
        ),
      ),
    );
  }

}