import 'package:flutter/material.dart';
import 'package:flutter_contacts/flutter_contacts.dart';
import 'package:uuid/uuid.dart';
import '../models/customer_model.dart';
import '../services/customer_repository.dart';

/// 顧客マスターからの選択、登録、編集、削除を行うモーダル
class CustomerPickerModal extends StatefulWidget {
  final Function(Customer) onCustomerSelected;

  const CustomerPickerModal({
    Key? key,
    required this.onCustomerSelected,
  }) : super(key: key);

  @override
  State<CustomerPickerModal> createState() => _CustomerPickerModalState();
}

class _CustomerPickerModalState extends State<CustomerPickerModal> {
  final CustomerRepository _repository = CustomerRepository();
  String _searchQuery = "";
  List<Customer> _allCustomers = [];
  List<Customer> _filteredCustomers = [];
  bool _isImportingFromContacts = false;
  bool _isLoading = true;

  @override
  void initState() {
    super.initState();
    _onSearch(""); // 初期表示
  }

  Future<void> _onSearch(String query) async {
    setState(() => _isLoading = true);
    final customers = await _repository.searchCustomers(query);
    setState(() {
      _filteredCustomers = customers;
      _isLoading = false;
    });
  }

  /// 電話帳から取り込んで新規顧客として登録・編集するダイアログ
  Future<void> _importFromPhoneContacts() async {
    setState(() => _isImportingFromContacts = true);
    try {
      if (await FlutterContacts.requestPermission(readonly: true)) {
        final contacts = await FlutterContacts.getContacts(withProperties: true, withAccounts: true, withPhoto: false);
        if (!mounted) return;
        setState(() => _isImportingFromContacts = false);

        final Contact? selectedContact = await showModalBottomSheet<Contact?>(
          context: context,
          isScrollControlled: true,
          builder: (context) => _PhoneContactListSelector(contacts: contacts),
        );

        if (selectedContact != null) {
          final orgCompany = (selectedContact.organizations.isNotEmpty ? selectedContact.organizations.first.company : '') ?? '';
          final personName = selectedContact.displayName;
          final display = orgCompany.isNotEmpty ? orgCompany : personName;
          final formal = orgCompany.isNotEmpty ? orgCompany : personName;
          _showCustomerEditDialog(
            displayName: display,
            initialFormalName: formal,
          );
        }
      }
    } catch (e) {
      setState(() => _isImportingFromContacts = false);
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(content: Text("電話帳の取得に失敗しました: $e")),
      );
    }
  }

  /// 顧客情報の編集・登録ダイアログ
  void _showCustomerEditDialog({
    required String displayName,
    required String initialFormalName,
    Customer? existingCustomer,
  }) {
    final formalNameController = TextEditingController(text: initialFormalName);
    final departmentController = TextEditingController(text: existingCustomer?.department ?? "");
    final addressController = TextEditingController(text: existingCustomer?.address ?? "");

    showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: Text(existingCustomer == null ? "顧客の新規登録" : "顧客情報の編集"),
        content: SingleChildScrollView(
          child: Column(
            mainAxisSize: MainAxisSize.min,
            children: [
              Text("電話帳名: $displayName", style: const TextStyle(fontSize: 12, color: Colors.grey)),
              const SizedBox(height: 16),
              TextField(
                controller: formalNameController,
                decoration: const InputDecoration(
                  labelText: "請求書用 正式名称",
                  hintText: "株式会社 〇〇 など",
                  border: OutlineInputBorder(),
                ),
              ),
              const SizedBox(height: 12),
              TextField(
                controller: departmentController,
                decoration: const InputDecoration(
                  labelText: "部署名",
                  border: OutlineInputBorder(),
                ),
              ),
              const SizedBox(height: 12),
              TextField(
                controller: addressController,
                decoration: const InputDecoration(
                  labelText: "住所",
                  border: OutlineInputBorder(),
                ),
              ),
            ],
          ),
        ),
        actions: [
          TextButton(onPressed: () => Navigator.pop(context), child: const Text("キャンセル")),
          ElevatedButton(
            onPressed: () async {
              final formal = formalNameController.text.trim();
              if (formal.isEmpty) {
                ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('正式名称を入力してください')));
                return;
              }
              String normalize(String s) {
                var n = s.replaceAll(RegExp(r"\s+|\u3000"), "");
                for (final token in ["株式会社", "（株）", "(株)", "有限会社", "（有）", "(有)", "合同会社", "（同）", "(同)"]) {
                  n = n.replaceAll(token, "");
                }
                return n.toLowerCase();
              }

              final normalizedFormal = normalize(formal);
              final duplicates = await _repository.getAllCustomers();
              final hasDuplicate = duplicates.any((c) {
                final target = normalize(c.formalName);
                return target == normalizedFormal && (existingCustomer == null || c.id != existingCustomer.id);
              });
              if (hasDuplicate) {
                ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('同一顧客名が存在します')));
                return;
              }

              final updatedCustomer = existingCustomer?.copyWith(
                    formalName: formal,
                    department: departmentController.text.trim(),
                    address: addressController.text.trim(),
                    updatedAt: DateTime.now(),
                    isSynced: false,
                  ) ??
                  Customer(
                    id: const Uuid().v4(),
                    displayName: displayName,
                    formalName: formal,
                    department: departmentController.text.trim(),
                    address: addressController.text.trim(),
                  );

              await _repository.saveCustomer(updatedCustomer);
              Navigator.pop(context); // エディットダイアログを閉じる
              _onSearch(_searchQuery); // リスト再読込
              if (existingCustomer == null) {
                widget.onCustomerSelected(updatedCustomer);
              }
            },
            child: const Text("保存してマスターに登録"),
          ),
        ],
      ),
    );
  }

  /// 削除確認ダイアログ
  void _confirmDelete(Customer customer) {
    showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: const Text("顧客の削除"),
        content: Text("「${customer.formalName}」をマスターから削除しますか？\n(過去の請求書ファイルは削除されません)"),
        actions: [
          TextButton(onPressed: () => Navigator.pop(context), child: const Text("キャンセル")),
          TextButton(
            onPressed: () async {
              await _repository.deleteCustomer(customer.id);
              Navigator.pop(context);
              _onSearch("");
            },
            child: const Text("削除する", style: TextStyle(color: Colors.red)),
          ),
        ],
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Material(
      child: Column(
        children: [
          Padding(
            padding: const EdgeInsets.all(16.0),
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                Row(
                  mainAxisAlignment: MainAxisAlignment.spaceBetween,
                  children: [
                    const Text("顧客マスター管理", style: TextStyle(fontSize: 20, fontWeight: FontWeight.bold)),
                    IconButton(icon: const Icon(Icons.close), onPressed: () => Navigator.pop(context)),
                  ],
                ),
                const SizedBox(height: 12),
                TextField(
                  decoration: InputDecoration(
                    hintText: "登録済み顧客を検索...",
                    prefixIcon: const Icon(Icons.search),
                    border: OutlineInputBorder(borderRadius: BorderRadius.circular(8)),
                  ),
                  onChanged: _onSearch,
                ),
                const SizedBox(height: 12),
                SizedBox(
                  width: double.infinity,
                  child: ElevatedButton.icon(
                    onPressed: _isImportingFromContacts ? null : _importFromPhoneContacts,
                    icon: _isImportingFromContacts
                        ? const SizedBox(width: 20, height: 20, child: CircularProgressIndicator(strokeWidth: 2))
                        : const Icon(Icons.contact_phone),
                    label: const Text("電話帳から新規取り込み"),
                    style: ElevatedButton.styleFrom(backgroundColor: Colors.blueGrey.shade700, foregroundColor: Colors.white),
                  ),
                ),
              ],
            ),
          ),
          const Divider(),
          Expanded(
            child: _isLoading 
                ? const Center(child: CircularProgressIndicator())
                : _filteredCustomers.isEmpty
                    ? const Center(child: Text("該当する顧客がいません"))
                    : ListView.builder(
                        itemCount: _filteredCustomers.length,
                        itemBuilder: (context, index) {
                          final customer = _filteredCustomers[index];
                          return ListTile(
                            leading: const CircleAvatar(child: Icon(Icons.business)),
                            title: Text(customer.formalName),
                            subtitle: Text(customer.department?.isNotEmpty == true ? customer.department! : "部署未設定"),
                            onTap: () => widget.onCustomerSelected(customer),
                            trailing: Row(
                              mainAxisSize: MainAxisSize.min,
                              children: [
                                IconButton(
                                  icon: const Icon(Icons.edit, color: Colors.blueGrey, size: 20),
                                  onPressed: () => _showCustomerEditDialog(
                                    displayName: customer.displayName,
                                    initialFormalName: customer.formalName,
                                    existingCustomer: customer,
                                  ),
                                ),
                                IconButton(
                                  icon: const Icon(Icons.delete_outline, color: Colors.redAccent, size: 20),
                                  onPressed: () => _confirmDelete(customer),
                                ),
                              ],
                            ),
                          );
                        },
                      ),
          ),
        ],
      ),
    );
  }
}

/// 電話帳から一人選ぶための内部ウィジェット
class _PhoneContactListSelector extends StatefulWidget {
  final List<Contact> contacts;
  const _PhoneContactListSelector({required this.contacts});

  @override
  State<_PhoneContactListSelector> createState() => _PhoneContactListSelectorState();
}

class _PhoneContactListSelectorState extends State<_PhoneContactListSelector> {
  List<Contact> _filtered = [];
  final _searchController = TextEditingController();

  @override
  void initState() {
    super.initState();
    _filtered = widget.contacts;
  }

  void _onSearch(String q) {
    setState(() {
      _filtered = widget.contacts
          .where((c) {
            final org = c.organizations.isNotEmpty ? c.organizations.first.company : '';
            final label = org.isNotEmpty ? org : c.displayName;
            return label.toLowerCase().contains(q.toLowerCase());
          })
          .toList();
    });
  }

  @override
  Widget build(BuildContext context) {
    return FractionallySizedBox(
      heightFactor: 0.8,
      child: Column(
        children: [
          Padding(
            padding: const EdgeInsets.all(16.0),
            child: TextField(
              controller: _searchController,
              decoration: const InputDecoration(hintText: "電話帳から検索...", prefixIcon: Icon(Icons.search)),
              onChanged: _onSearch,
            ),
          ),
          Expanded(
            child: ListView.builder(
              itemCount: _filtered.length,
              itemBuilder: (context, index) => ListTile(
                title: Text(((_filtered[index].organizations.isNotEmpty ? _filtered[index].organizations.first.company : '') ?? '').isNotEmpty
                  ? _filtered[index].organizations.first.company
                  : _filtered[index].displayName),
                onTap: () => Navigator.pop(context, _filtered[index]),
              ),
            ),
          ),
        ],
      ),
    );
  }
}