Menu with user choices
	•	Input handling for lights, thermostat, and security
	•	FizzBuzz-style temperature messages (“Cool Day”, “Warm Day”, “Perfect Day”)

•	Proper use of constants, conditions, and string interpolation


import 'dart:io';

void main() {
  // الثوابت الخاصة بدرجات الحرارة
  const int minTemp = 15;
  const int maxTemp = 30;

  // القيم الافتراضية للأجهزة
  bool lightsOn = false;
  int thermostat = 20;
  bool securityArmed = false;

  while (true) {
    print('\nWelcome to the Smart Home System!');
    print('Please choose an action:');
    print('1. Toggle lights');
    print('2. Set thermostat temperature');
    print('3. Arm/disarm security system');
    print('4. View system status');
    print('5. Exit');

    stdout.write('\nEnter your choice: ');
    String? choice = stdin.readLineSync();

    if (choice == null) continue;

    switch (choice) {
      case '1':
        // تشغيل أو إطفاء الأضواء
        lightsOn = !lightsOn;
        print('Lights are now ${lightsOn ? 'ON' : 'OFF'}.');
        break;

      case '2':
        // ضبط درجة الحرارة
        stdout.write('Set thermostat temperature ($minTemp°C - $maxTemp°C): ');
        String? tempInput = stdin.readLineSync();
        int? temp = int.tryParse(tempInput ?? '');

        if (temp == null || temp < minTemp || temp > maxTemp) {
          print('Invalid temperature! Please enter a value between $minTemp and $maxTemp.');
        } else {
          thermostat = temp;
          print('Thermostat set to ${thermostat}°C.');
        }
        break;

      case '3':
        // تفعيل أو إلغاء النظام الأمني
        securityArmed = !securityArmed;
        print('Security system is now ${securityArmed ? 'ARMED' : 'DISARMED'}.');
        break;

      case '4':
        // عرض حالة النظام
        print('\nSystem Status:');
        print('- Lights: ${lightsOn ? 'ON' : 'OFF'}');
        print('- Thermostat: ${thermostat}°C ${getTempStatus(thermostat)}');
        print('- Security System: ${securityArmed ? 'ARMED' : 'DISARMED'}');
        break;

      case '5':
        print('Exiting the system, Goodbye!');
        return;

      default:
        print('Invalid choice! Please try again.');
    }
  }
}

// دالة لتحديد حالة درجة الحرارة (FizzBuzz logic)
String getTempStatus(int temp) {
  if (temp % 3 == 0 && temp % 5 == 0) {
    return '- Perfect Day';
  } else if (temp % 3 == 0) {
    return '- Cool Day';
  } else if (temp % 5 == 0) {
    return '- Warm Day';
  } else {
    return '';
  }
}