import 'package:flutter/material.dart';

class NavigationProvider extends ChangeNotifier {
  int _currentIndex = 0;
  final List<int> _navigationHistory = [0];
  String _currentRoute = '/';
  String _currentTitle = '홈';

  int get currentIndex => _currentIndex;
  List<int> get navigationHistory => List.unmodifiable(_navigationHistory);
  String get currentRoute => _currentRoute;
  String get currentTitle => _currentTitle;

  static const Map<String, int> routeToIndex = {
    '/': 0,
    '/add-subscription': -1,
    '/sms-scanner': 3,
    '/analysis': 1,
    '/settings': 4,
    '/subscription-detail': -1,
  };

  static const Map<int, String> indexToRoute = {
    0: '/',
    1: '/analysis',
    3: '/sms-scanner',
    4: '/settings',
  };

  static const Map<int, String> indexToTitle = {
    0: '홈',
    1: '분석',
    3: 'SMS 스캔',
    4: '설정',
  };

  void updateCurrentIndex(int index, {bool addToHistory = true}) {
    if (_currentIndex == index) return;
    
    _currentIndex = index;
    _currentRoute = indexToRoute[index] ?? '/';
    _currentTitle = indexToTitle[index] ?? '홈';
    
    if (addToHistory && index >= 0) {
      _navigationHistory.add(index);
      if (_navigationHistory.length > 10) {
        _navigationHistory.removeAt(0);
      }
    }
    
    notifyListeners();
  }

  void updateByRoute(String route) {
    final index = routeToIndex[route] ?? 0;
    _currentRoute = route;
    
    if (index >= 0) {
      _currentIndex = index;
      _currentTitle = indexToTitle[index] ?? '홈';
    } else {
      switch (route) {
        case '/add-subscription':
          _currentTitle = '구독 추가';
          break;
        case '/subscription-detail':
          _currentTitle = '구독 상세';
          break;
        default:
          _currentTitle = '홈';
      }
    }
    
    notifyListeners();
  }

  bool canPop() {
    return _navigationHistory.length > 1;
  }

  void pop() {
    if (_navigationHistory.length > 1) {
      _navigationHistory.removeLast();
      final previousIndex = _navigationHistory.last;
      updateCurrentIndex(previousIndex, addToHistory: false);
    }
  }

  void reset() {
    _currentIndex = 0;
    _currentRoute = '/';
    _currentTitle = '홈';
    _navigationHistory.clear();
    _navigationHistory.add(0);
    notifyListeners();
  }

  void clearHistoryAndGoHome() {
    _currentIndex = 0;
    _currentRoute = '/';
    _currentTitle = '홈';
    _navigationHistory.clear();
    _navigationHistory.add(0);
    notifyListeners();
  }
}