h-1.flutter.4/lib/screens/master/inventory_master_screen.dart

// Version: 1.7 - 在庫管理画面
import 'package:flutter/material.dart';
import '../../models/product.dart';
import '../../services/database_helper.dart';

/// 在庫管理画面（新規登録・一覧表示）
class InventoryMasterScreen extends StatefulWidget {
  const InventoryMasterScreen({super.key});

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

class _InventoryMasterScreenState extends State<InventoryMasterScreen> {
  List<Product> _products = [];
  Map<String, dynamic>? _newInventory; // 新規登録用データ

  @override
  void initState() {
    super.initState();
    _loadProducts();
  }

  Future<void> _loadProducts() async {
    try {
      final products = await DatabaseHelper.instance.getProducts();
      if (mounted) setState(() => _products = products ?? const <Product>[]);
    } catch (e) {}
  }

  void _submitNewInventory() async {
    if (_newInventory == null || !(_newInventory!['product_code'] as String).isNotEmpty) return;

    try {
      final db = await DatabaseHelper.instance.database;
      // product_code の一意性チェック
      final existing = await db.query('inventory', where: "product_code = ?", whereArgs: [(_newInventory!['product_code'] as String)]);
      if (existing.isNotEmpty) {
        ScaffoldMessenger.of(context).showSnackBar(
          const SnackBar(content: Text('同じ JAN コードの在庫は既に存在します'), backgroundColor: Colors.orange),
        );
        return;
      }

      final inventoryData = <String, dynamic>{
        'product_code': _newInventory!['product_code'] as String,
        'name': _newInventory!['name'] as String? ?? '',
        'unit_price': (_newInventory!['unit_price'] as num?)?.toInt() ?? 0,
        'stock': (_newInventory!['stock'] as num?)?.toInt() ?? 0,
        'min_stock': (_newInventory!['min_stock'] as num?)?.toInt() ?? 10,
        'max_stock': (_newInventory!['max_stock'] as num?)?.toInt() ?? 1000,
        'supplier_name': _newInventory!['supplier_name'] as String? ?? '',
      };

      await DatabaseHelper.instance.insertInventory(inventoryData);

      if (mounted) ScaffoldMessenger.of(context).showSnackBar(
        const SnackBar(content: Text('在庫登録完了'), backgroundColor: Colors.green),
      );
      setState(() => _newInventory = null);
      _loadProducts();
    } catch (e) {
      if (mounted) ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(content: Text('保存エラー：$e'), backgroundColor: Colors.red),
      );
    }
  }

  void _showAddDialog() {
    showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: const Text('新規在庫登録'),
        content: SingleChildScrollView(
          child: Column(
            mainAxisSize: MainAxisSize.min,
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              TextField(
                decoration: const InputDecoration(labelText: 'JAN コード', hintText: '例：4901234567890'),
                onChanged: (v) => _newInventory?['product_code'] = v,
              ),
              TextField(
                decoration: const InputDecoration(labelText: '商品名', hintText: '商品名を入力'),
                onChanged: (v) => _newInventory?['name'] = v,
              ),
              TextField(
                decoration: const InputDecoration(labelText: '単価（円）', hintText: '0'),
                keyboardType: TextInputType.number,
                onChanged: (v) => _newInventory?['unit_price'] = int.tryParse(v),
              ),
              TextField(
                decoration: const InputDecoration(labelText: '在庫数', hintText: '0'),
                keyboardType: TextInputType.number,
                onChanged: (v) => _newInventory?['stock'] = int.tryParse(v),
              ),
              TextField(
                decoration: const InputDecoration(labelText: '最低在庫', hintText: '10'),
                keyboardType: TextInputType.number,
                onChanged: (v) => _newInventory?['min_stock'] = int.tryParse(v),
              ),
              TextField(
                decoration: const InputDecoration(labelText: '最大在庫', hintText: '1000'),
                keyboardType: TextInputType.number,
                onChanged: (v) => _newInventory?['max_stock'] = int.tryParse(v),
              ),
              TextField(
                decoration: const InputDecoration(labelText: '仕入先', hintText: '仕入先会社名'),
                onChanged: (v) => _newInventory?['supplier_name'] = v,
              ),
            ],
          ),
        ),
        actions: [
          TextButton(onPressed: () => Navigator.pop(context), child: const Text('キャンセル')),
          ElevatedButton(
            onPressed: _newInventory != null ? _submitNewInventory : null,
            child: const Text('登録'),
          ),
        ],
      ),
    );
  }

  void _editInventory(int id) async {
    final product = await DatabaseHelper.instance.getProduct(id);
    if (product == null || mounted) return;

    showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: const Text('在庫編集'),
        content: SingleChildScrollView(
          child: Column(
            mainAxisSize: MainAxisSize.min,
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              TextField(
                decoration: InputDecoration(labelText: 'JAN コード', hintText: product.productCode),
                readOnly: true,
              ),
              TextField(
                decoration: const InputDecoration(labelText: '商品名'),
                controller: TextEditingController(text: product.name),
                onChanged: (v) {
                  _updateInventory(id, {'name': v});
                },
              ),
              TextField(
                decoration: const InputDecoration(labelText: '単価（円）'),
                keyboardType: TextInputType.number,
                onChanged: (v) => _updateInventory(id, {'unit_price': int.tryParse(v)}),
              ),
              TextField(
                decoration: const InputDecoration(labelText: '在庫数'),
                keyboardType: TextInputType.number,
                onChanged: (v) => _updateInventory(id, {'stock': int.tryParse(v)}),
              ),
              TextField(
                decoration: const InputDecoration(labelText: '最低在庫'),
                keyboardType: TextInputType.number,
                onChanged: (v) => _updateInventory(id, {'min_stock': int.tryParse(v)}),
              ),
              TextField(
                decoration: const InputDecoration(labelText: '最大在庫'),
                keyboardType: TextInputType.number,
                onChanged: (v) => _updateInventory(id, {'max_stock': int.tryParse(v)}),
              ),
              TextField(
                decoration: const InputDecoration(labelText: '仕入先'),
                onChanged: (v) => _updateInventory(id, {'supplier_name': v}),
              ),
            ],
          ),
        ),
        actions: [
          TextButton(onPressed: () => Navigator.pop(context), child: const Text('キャンセル')),
          ElevatedButton(
            onPressed: () => Navigator.pop(context),
            child: const Text('保存'),
          ),
        ],
      ),
    );
  }

  void _updateInventory(int id, Map<String, dynamic> data) async {
    final inventoryData = <String, dynamic>{
      'product_code': data['product_code'] as String?,
      'name': data['name'] as String?,
      'unit_price': data['unit_price'] as int?,
      'stock': data['stock'] as int?,
      'min_stock': data['min_stock'] as int?,
      'max_stock': data['max_stock'] as int?,
      'supplier_name': data['supplier_name'] as String?,
    };

    try {
      await DatabaseHelper.instance.updateInventory(inventoryData);
      ScaffoldMessenger.of(context).showSnackBar(
        const SnackBar(content: Text('在庫更新完了'), backgroundColor: Colors.green),
      );
      _loadProducts();
    } catch (e) {}
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('在庫管理'),
        actions: [
          IconButton(icon: const Icon(Icons.refresh), onPressed: _loadProducts,),
        ],
      ),
      body: _products.isEmpty ? Center(child: const Text('在庫データがありません')) :
            SingleChildScrollView(
              padding: const EdgeInsets.all(16),
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.stretch,
                children: [
                  Card(
                    child: ListTile(
                      title: const Text('新規登録'),
                      subtitle: const Text('商品への在庫を登録'),
                      trailing: const Icon(Icons.add_circle),
                      onTap: _showAddDialog,
                    ),
                  ),
                  const SizedBox(height: 16),
                  ListView.builder(
                    shrinkWrap: true,
                    physics: const NeverScrollableScrollPhysics(),
                    itemCount: _products.length,
                    itemBuilder: (context, index) {
                      final product = _products[index];
                      return Card(
                        margin: const EdgeInsets.only(bottom: 8),
                        child: ListTile(
                          title: Text(product.name),
                          subtitle: Text('JAN: ${product.productCode} / ¥${product.unitPrice} × ${product.stock ?? 0}'),
                          trailing: IconButton(icon: const Icon(Icons.edit), onPressed: () => _editInventory(product.id ?? 0),),
                        ),
                      );
                    },
                  ),
                ],
              ),
            ),
    );
  }
}