import 'dart:async';
import 'package:flutter/material.dart';
import 'package:get_it/get_it.dart';
import 'package:superport/models/company_model.dart';
import 'package:superport/models/user_model.dart';
import 'package:superport/services/mock_data_service.dart';
import 'package:superport/services/user_service.dart';
import 'package:superport/utils/constants.dart';
import 'package:superport/models/user_phone_field.dart';

// 사용자 폼의 상태 및 비즈니스 로직을 담당하는 컨트롤러
class UserFormController extends ChangeNotifier {
  final MockDataService dataService;
  final UserService _userService = GetIt.instance<UserService>();
  final GlobalKey<FormState> formKey = GlobalKey<FormState>();

  // 상태 변수
  bool _isLoading = false;
  String? _error;
  bool _useApi = true; // Feature flag
  
  // 폼 필드
  bool isEditMode = false;
  int? userId;
  String name = '';
  String username = ''; // 추가
  String password = ''; // 추가
  int? companyId;
  int? branchId;
  String role = UserRoles.member;
  String position = '';
  String email = '';
  
  // username 중복 확인
  bool _isCheckingUsername = false;
  bool? _isUsernameAvailable;
  String? _lastCheckedUsername;
  Timer? _usernameCheckTimer;

  // 전화번호 관련 상태
  final List<UserPhoneField> phoneFields = [];
  final List<String> phoneTypes = ['휴대폰', '사무실', '팩스', '기타'];

  List<Company> companies = [];
  List<Branch> branches = [];
  
  // Getters
  bool get isLoading => _isLoading;
  String? get error => _error;
  bool get isCheckingUsername => _isCheckingUsername;
  bool? get isUsernameAvailable => _isUsernameAvailable;

  UserFormController({required this.dataService, this.userId}) {
    isEditMode = userId != null;
    if (isEditMode) {
      loadUser();
    } else {
      addPhoneField();
    }
    loadCompanies();
  }

  // 회사 목록 로드
  void loadCompanies() {
    companies = dataService.getAllCompanies();
    notifyListeners();
  }

  // 회사 ID에 따라 지점 목록 로드
  void loadBranches(int companyId) {
    final company = dataService.getCompanyById(companyId);
    branches = company?.branches ?? [];
    // 지점 변경 시 이전 선택 지점이 새 회사에 없으면 초기화
    if (branchId != null && !branches.any((b) => b.id == branchId)) {
      branchId = null;
    }
    notifyListeners();
  }

  // 사용자 정보 로드 (수정 모드)
  Future<void> loadUser() async {
    if (userId == null) return;
    
    _isLoading = true;
    _error = null;
    notifyListeners();
    
    try {
      User? user;
      
      if (_useApi) {
        user = await _userService.getUser(userId!);
      } else {
        user = dataService.getUserById(userId!);
      }
      
      if (user != null) {
        name = user.name;
        username = user.username ?? '';
        companyId = user.companyId;
        branchId = user.branchId;
        role = user.role;
        position = user.position ?? '';
        email = user.email ?? '';
        if (companyId != null) {
          loadBranches(companyId!);
        }
        phoneFields.clear();
        if (user.phoneNumbers.isNotEmpty) {
          for (var phone in user.phoneNumbers) {
            phoneFields.add(
              UserPhoneField(
                type: phone['type'] ?? '휴대폰',
                initialValue: phone['number'] ?? '',
              ),
            );
          }
        } else {
          addPhoneField();
        }
      }
    } catch (e) {
      _error = e.toString();
    } finally {
      _isLoading = false;
      notifyListeners();
    }
  }

  // 전화번호 필드 추가
  void addPhoneField() {
    phoneFields.add(UserPhoneField(type: '휴대폰'));
    notifyListeners();
  }

  // 전화번호 필드 삭제
  void removePhoneField(int index) {
    if (phoneFields.length > 1) {
      phoneFields[index].dispose();
      phoneFields.removeAt(index);
      notifyListeners();
    }
  }
  
  // Username 중복 확인
  void checkUsernameAvailability(String value) {
    if (value.isEmpty || value == _lastCheckedUsername) {
      return;
    }
    
    // 디바운싱
    _usernameCheckTimer?.cancel();
    _usernameCheckTimer = Timer(const Duration(milliseconds: 500), () async {
      _isCheckingUsername = true;
      notifyListeners();
      
      try {
        if (_useApi) {
          final isDuplicate = await _userService.checkDuplicateUsername(value);
          _isUsernameAvailable = !isDuplicate;
        } else {
          // Mock 데이터에서 중복 확인
          final users = dataService.getAllUsers();
          final exists = users.any((u) => u.username == value && u.id != userId);
          _isUsernameAvailable = !exists;
        }
        _lastCheckedUsername = value;
      } catch (e) {
        _isUsernameAvailable = null;
      } finally {
        _isCheckingUsername = false;
        notifyListeners();
      }
    });
  }

  // 사용자 저장 (UI에서 호출)
  Future<void> saveUser(Function(String? error) onResult) async {
    if (formKey.currentState?.validate() != true) {
      onResult('폼 유효성 검사 실패');
      return;
    }
    formKey.currentState?.save();
    
    if (companyId == null) {
      onResult('소속 회사를 선택해주세요');
      return;
    }
    
    // 신규 등록 시 username 중복 확인
    if (!isEditMode) {
      if (username.isEmpty) {
        onResult('사용자명을 입력해주세요');
        return;
      }
      if (_isUsernameAvailable == false) {
        onResult('이미 사용중인 사용자명입니다');
        return;
      }
      if (password.isEmpty) {
        onResult('비밀번호를 입력해주세요');
        return;
      }
    }
    
    _isLoading = true;
    _error = null;
    notifyListeners();
    
    try {
      // 전화번호 목록 준비
      String? phoneNumber;
      for (var phoneField in phoneFields) {
        if (phoneField.number.isNotEmpty) {
          phoneNumber = phoneField.number;
          break; // API는 단일 전화번호만 지원
        }
      }
      
      if (_useApi) {
        if (isEditMode && userId != null) {
          // 사용자 수정
          await _userService.updateUser(
            userId!,
            name: name,
            email: email.isNotEmpty ? email : null,
            phone: phoneNumber,
            companyId: companyId,
            branchId: branchId,
            role: role,
            position: position.isNotEmpty ? position : null,
            password: password.isNotEmpty ? password : null,
          );
        } else {
          // 사용자 생성
          await _userService.createUser(
            username: username,
            email: email,
            password: password,
            name: name,
            role: role,
            companyId: companyId!,
            branchId: branchId,
            phone: phoneNumber,
            position: position.isNotEmpty ? position : null,
          );
        }
      } else {
        // Mock 데이터 사용
        List<Map<String, String>> phoneNumbersList = [];
        for (var phoneField in phoneFields) {
          if (phoneField.number.isNotEmpty) {
            phoneNumbersList.add({
              'type': phoneField.type,
              'number': phoneField.number,
            });
          }
        }
        
        if (isEditMode && userId != null) {
          final user = dataService.getUserById(userId!);
          if (user != null) {
            final updatedUser = User(
              id: user.id,
              companyId: companyId!,
              branchId: branchId,
              name: name,
              role: role,
              position: position.isNotEmpty ? position : null,
              email: email.isNotEmpty ? email : null,
              phoneNumbers: phoneNumbersList,
              username: username.isNotEmpty ? username : null,
              isActive: user.isActive,
              createdAt: user.createdAt,
              updatedAt: DateTime.now(),
            );
            dataService.updateUser(updatedUser);
          }
        } else {
          final newUser = User(
            companyId: companyId!,
            branchId: branchId,
            name: name,
            role: role,
            position: position.isNotEmpty ? position : null,
            email: email.isNotEmpty ? email : null,
            phoneNumbers: phoneNumbersList,
            username: username,
            isActive: true,
            createdAt: DateTime.now(),
            updatedAt: DateTime.now(),
          );
          dataService.addUser(newUser);
        }
      }
      
      onResult(null);
    } catch (e) {
      _error = e.toString();
      onResult(_error);
    } finally {
      _isLoading = false;
      notifyListeners();
    }
  }

  // 컨트롤러 해제
  @override
  void dispose() {
    _usernameCheckTimer?.cancel();
    for (var phoneField in phoneFields) {
      phoneField.dispose();
    }
    super.dispose();
  }
  
  // API/Mock 모드 전환
  void toggleApiMode() {
    _useApi = !_useApi;
    notifyListeners();
  }
}