import 'package:flutter/material.dart';
import 'package:shared_preferences/shared_preferences.dart';

Future<void> saveDarkMode(bool isDark) async {
  final prefs = await SharedPreferences.getInstance();
  await prefs.setBool('darkMode', isDark);
}

Future<bool> loadDarkMode() async {
  final prefs = await SharedPreferences.getInstance();
  return prefs.getBool('darkMode') ?? false; // default light
}

class ThemeProvider extends ChangeNotifier {
  bool _isDark;

  bool get isDark => _isDark;

  ThemeProvider({required bool isDark}) : _isDark = isDark;

  void setDarkMode(bool value) {
    if (_isDark == value) return; // avoid unnecessary rebuilds
    _isDark = value;
    notifyListeners();
    saveDarkMode(value);
  }
}