// Version: 3.0 - シンプル顧客マスタ画面（簡素版、サンプルデータ固定）

import 'package:flutter/material.dart';

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

  @override
  State<CustomerMasterScreen> createState() => _CustomerMasterScreenState();
}

class _CustomerMasterScreenState extends State<CustomerMasterScreen> {
  List<dynamic> _customers = [];

  @override
  void initState() {
    super.initState();
    // サンプルデータ（簡素版）
    _customers = [
      {'customer_code': 'C001', 'name': 'サンプル顧客 A'},
      {'customer_code': 'C002', 'name': 'サンプル顧客 B'},
    ];
  }

  Future<void> _addCustomer() async {
    await showDialog<dynamic>(
      context: context,
      builder: (ctx) => AlertDialog(
        title: const Text('新規顧客登録'),
        content: SingleChildScrollView(
          child: Column(
            mainAxisSize: MainAxisSize.min,
            crossAxisAlignment: CrossAxisAlignment.stretch,
            children: [
              TextField(decoration: const InputDecoration(labelText: 'コード', hintText: 'C003')),
              SizedBox(height: 8),
              TextField(decoration: const InputDecoration(labelText: '名称', hintText: '新顧客名'), onChanged: (v) => setState(() {})),
              SizedBox(height: 8),
              TextField(decoration: const InputDecoration(labelText: '住所', hintText: '住所を入力')),
              SizedBox(height: 8),
              TextField(decoration: const InputDecoration(labelText: '電話番号', hintText: '03-1234-5678'), keyboardType: TextInputType.phone, onChanged: (v) => setState(() {})),
            ],
          ),
        ),
        actions: [
          TextButton(onPressed: () => Navigator.pop(ctx), child: const Text('キャンセル')),
          ElevatedButton(
            onPressed: () {
              Navigator.pop(ctx);
            },
            child: const Text('登録'),
          ),
        ],
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('/M2. 顧客マスタ')),
      body: _customers.isEmpty ? Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Icon(Icons.inbox_outlined, size: 64, color: Colors.grey[300]),
            SizedBox(height: 16),
            Text('顧客データがありません', style: TextStyle(color: Colors.grey)),
            SizedBox(height: 16),
            FloatingActionButton.extended(
              icon: Icon(Icons.add, color: Theme.of(context).primaryColor),
              label: const Text('新規登録'),
              onPressed: _addCustomer,
            ),
          ],
        ),
      ) : ListView.builder(
        padding: const EdgeInsets.all(8),
        itemCount: _customers.length,
        itemBuilder: (context, index) {
          final customer = _customers[index];
          return Card(
            margin: EdgeInsets.zero,
            clipBehavior: Clip.antiAlias,
            child: ListTile(
              leading: CircleAvatar(backgroundColor: Colors.green.shade100, child: Text(customer['customer_code'] ?? '-', style: const TextStyle(fontWeight: FontWeight.bold))),
              title: Text(customer['name'] ?? '未入力'),
              subtitle: Column(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  if (customer['phone'] != null) Text('電話：${customer['phone']}', style: const TextStyle(fontSize: 12)),
                ],
              ),
            ),
          );
        },
      ),
      floatingActionButton: FloatingActionButton.extended(
        icon: const Icon(Icons.add),
        label: const Text('新規登録'),
        onPressed: _addCustomer,
      ),
    );
  }
}