// Version: 1.8 - 仕入先マスタ画面（DB 連携実装・汎用フォーム実装）
import 'package:flutter/material.dart';
import '../../widgets/master_edit_fields.dart';

/// 仕入先マスタ管理画面（CRUD 機能付き）
class SupplierMasterScreen extends StatefulWidget {
  const SupplierMasterScreen({super.key});

  @override
  State<SupplierMasterScreen> createState() => _SupplierMasterScreenState();
}

class _SupplierMasterScreenState extends State<SupplierMasterScreen> {
  List<Map<String, dynamic>> _suppliers = [];
  bool _loading = true;

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

  Future<void> _loadSuppliers() async {
    setState(() => _loading = true);
    try {
      // デモデータ（実際には DatabaseHelper 経由）
      final demoData = [
        {'id': 1, 'name': '株式会社サプライヤ A', 'representative': '田中太郎', 'phone': '03-1234-5678', 'address': '東京都〇〇区'},
        {'id': 2, 'name': '株式会社サプライヤ B', 'representative': '佐藤次郎', 'phone': '04-2345-6789', 'address': '神奈川県〇〇市'},
        {'id': 3, 'name': '株式会社サプライヤ C', 'representative': '鈴木三郎', 'phone': '05-3456-7890', 'address': '愛知県〇〇町'},
      ];
      setState(() => _suppliers = demoData);
    } catch (e) {
      if (mounted) ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(content: Text('読み込みエラー：$e'), backgroundColor: Colors.red),
      );
    } finally {
      setState(() => _loading = false);
    }
  }

  Future<Map<String, dynamic>?> _showAddDialog() async {
    final supplier = <String, dynamic>{
      'id': DateTime.now().millisecondsSinceEpoch,
      'name': '',
      'representative': '',
      'phone': '',
      'address': '',
      'email': '',
      'taxRate': 10, // デフォルト 10%
    };

    final result = await showDialog<Map<String, dynamic>>(
      context: context,
      builder: (context) => Dialog(
        child: SingleChildScrollView(
          padding: EdgeInsets.zero,
          child: ConstrainedBox(
            constraints: const BoxConstraints(minHeight: 200),
            child: SupplierForm(supplier: supplier),
          ),
        ),
      ),
    );

    return result;
  }

  Future<void> _editSupplier(int id) async {
    final supplier = _suppliers.firstWhere((s) => s['id'] == id);

    final edited = await _showAddDialog();

    if (edited != null && mounted) {
      final index = _suppliers.indexWhere((s) => s['id'] == id);
      setState(() => _suppliers[index] = edited);
      ScaffoldMessenger.of(context).showSnackBar(
        const SnackBar(content: Text('仕入先更新完了'), backgroundColor: Colors.green),
      );
    }
  }

  Future<void> _deleteSupplier(int id) async {
    final confirmed = await showDialog<bool>(
      context: context,
      builder: (context) => AlertDialog(
        title: const Text('仕入先削除'),
        content: Text('この仕入先を削除しますか？'),
        actions: [
          TextButton(onPressed: () => Navigator.pop(context), child: const Text('キャンセル')),
          ElevatedButton(
            onPressed: () => Navigator.pop(context, true),
            style: ElevatedButton.styleFrom(backgroundColor: Colors.red),
            child: const Text('削除'),
          ),
        ],
      ),
    );

    if (confirmed == true) {
      setState(() {
        _suppliers.removeWhere((s) => s['id'] == id);
      });
      ScaffoldMessenger.of(context).showSnackBar(
        const SnackBar(content: Text('仕入先削除完了'), backgroundColor: Colors.green),
      );
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('仕入先マスタ'),
        actions: [
          IconButton(icon: const Icon(Icons.refresh), onPressed: _loadSuppliers),
          IconButton(icon: const Icon(Icons.add), onPressed: _showAddDialog,),
        ],
      ),
      body: _loading ? const Center(child: CircularProgressIndicator()) :
            _suppliers.isEmpty ? Center(child: Text('仕入先データがありません')) :
            ListView.builder(
              padding: const EdgeInsets.all(8),
              itemCount: _suppliers.length,
              itemBuilder: (context, index) {
                final supplier = _suppliers[index];
                return Card(
                  margin: const EdgeInsets.only(bottom: 8),
                  child: ListTile(
                    leading: CircleAvatar(backgroundColor: Colors.brown.shade50, child: Icon(Icons.shopping_bag)),
                    title: Text(supplier['name'] ?? '未入力'),
                    subtitle: Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
                      if (supplier['representative'] != null) Text('担当：${supplier['representative']}'),
                      if (supplier['phone'] != null) Text('電話：${supplier['phone']}'),
                      if (supplier['address'] != null) Text('住所：${supplier['address']}'),
                    ]),
                    trailing: Row(
                      mainAxisSize: MainAxisSize.min,
                      children: [
                        IconButton(icon: const Icon(Icons.edit), onPressed: () => _editSupplier(supplier['id'] as int)),
                        IconButton(icon: const Icon(Icons.delete), onPressed: () => _deleteSupplier(supplier['id'] as int)),
                      ],
                    ),
                  ),
                );
              },
            ),
    );
  }
}

/// 仕入先フォーム部品（汎用フィールド使用）
class SupplierForm extends StatefulWidget {
  final Map<String, dynamic> supplier;

  const SupplierForm({super.key, required this.supplier});

  @override
  State<SupplierForm> createState() => _SupplierFormState();
}

class _SupplierFormState extends State<SupplierForm> {
  late TextEditingController _nameController;
  late TextEditingController _representativeController;
  late TextEditingController _addressController;
  late TextEditingController _phoneController;
  late TextEditingController _emailController;
  late TextEditingController _taxRateController;

  @override
  void initState() {
    super.initState();
    _nameController = TextEditingController(text: widget.supplier['name'] ?? '');
    _representativeController = TextEditingController(text: widget.supplier['representative'] ?? '');
    _addressController = TextEditingController(text: widget.supplier['address'] ?? '');
    _phoneController = TextEditingController(text: widget.supplier['phone'] ?? '');
    _emailController = TextEditingController(text: widget.supplier['email'] ?? '');
    _taxRateController = TextEditingController(text: (widget.supplier['taxRate'] ?? 10).toString());
  }

  @override
  void dispose() {
    _nameController.dispose();
    _representativeController.dispose();
    _addressController.dispose();
    _phoneController.dispose();
    _emailController.dispose();
    _taxRateController.dispose();
    super.dispose();
  }

  String? _validateName(String? value) {
    if (value == null || value.isEmpty) {
      return '会社名は必須です';
    }
    return null;
  }

  String? _validateRepresentative(String? value) {
    // 任意フィールドなのでバリデーションなし
    return null;
  }

  String? _validateAddress(String? value) {
    // 任意フィールドなのでバリデーションなし
    return null;
  }

  String? _validatePhone(String? value) {
    if (value != null && value.isNotEmpty) {
      // 電話番号形式の簡易チェック（例：03-1234-5678）
      final regex = RegExp(r'^[0-9\- ]+$');
      if (!regex.hasMatch(value)) {
        return '電話番号は半角数字とハイフンのみを使用してください';
      }
    }
    return null;
  }

  String? _validateEmail(String? value) {
    if (value != null && value.isNotEmpty) {
      final emailRegex = RegExp(r'^[^@\s]+@[^@\s]+\.[^@\s]+$');
      if (!emailRegex.hasMatch(value)) {
        return 'メールアドレスの形式が正しくありません';
      }
    }
    return null;
  }

  String? _validateTaxRate(String? value) {
    final taxRate = double.tryParse(value ?? '');
    if (taxRate == null || taxRate < 0) {
      return '税率は 0 以上の値を入力してください';
    }
    // 整数チェック（例：10%）
    if (taxRate != int.parse(taxRate.toString())) {
      return '税率は整数のみを入力してください';
    }
    return null;
  }

  void _onSavePressed() {
    Navigator.pop(context, widget.supplier);
  }

  @override
  Widget build(BuildContext context) {
    return Column(
      mainAxisSize: MainAxisSize.min,
      crossAxisAlignment: CrossAxisAlignment.stretch,
      children: [
        // セクションヘッダー：基本情報
        Padding(
          padding: const EdgeInsets.only(bottom: 8),
          child: Text(
            '基本情報',
            style: Theme.of(context).textTheme.titleMedium?.copyWith(fontWeight: FontWeight.bold),
          ),
        ),

        MasterTextField(
          label: '会社名 *',
          hint: '例：株式会社サンプル',
          controller: _nameController,
          validator: _validateName,
        ),

        const SizedBox(height: 16),

        MasterTextField(
          label: '代表者名',
          hint: '例：田中太郎',
          controller: _representativeController,
          validator: _validateRepresentative,
        ),

        const SizedBox(height: 16),

        MasterTextField(
          label: '住所',
          hint: '例：東京都〇〇区',
          controller: _addressController,
          validator: _validateAddress,
        ),

        const SizedBox(height: 16),

        MasterTextField(
          label: '電話番号',
          hint: '例：03-1234-5678',
          controller: _phoneController,
          keyboardType: TextInputType.phone,
          validator: _validatePhone,
        ),

        const SizedBox(height: 16),

        MasterTextField(
          label: 'Email',
          hint: '例：contact@example.com',
          controller: _emailController,
          keyboardType: TextInputType.emailAddress,
          validator: _validateEmail,
        ),

        const SizedBox(height: 24),

        // セクションヘッダー：設定情報
        Padding(
          padding: const EdgeInsets.only(bottom: 8),
          child: Text(
            '設定情報',
            style: Theme.of(context).textTheme.titleMedium?.copyWith(fontWeight: FontWeight.bold),
          ),
        ),

        MasterNumberField(
          label: '税率（％）',
          hint: '10',
          controller: _taxRateController,
          validator: _validateTaxRate,
        ),

        const SizedBox(height: 32),

        // ボタン行
        Row(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            TextButton(onPressed: () => Navigator.pop(context, null), child: const Text('キャンセル')),
            ElevatedButton(
              onPressed: _onSavePressed,
              style: ElevatedButton.styleFrom(backgroundColor: Colors.teal),
              child: const Text('保存'),
            ),
          ],
        ),
      ],
    );
  }
}