import 'dart:io';

const int minTemp = 15;
const int maxTemp = 30;

void main() {
  bool lightsOn = false;
  int thermostat = 20;
  bool securityArmed = false;

  while (true) {
    print('\n=== Smart Home Menu ===');
    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('Enter your choice: ');
    String? choice = stdin.readLineSync();

    if (choice == '5') {
      print('Exiting Smart Home System. Goodbye!');
      break;
    }

    switch (choice) {
      case '1':
        lightsOn = !lightsOn;
        print('Lights turned ${lightsOn ? "ON" : "OFF"}');
        break;

      case '2':
        stdout.write('Enter temperature ($minTemp-$maxTemp): ');
        String? input = stdin.readLineSync();
        int? temp = int.tryParse(input!);

        if (temp != null && temp >= minTemp && temp <= maxTemp) {
          thermostat = temp;
          print('Thermostat set to $thermostat°C');
        } else {
          print('Invalid temperature! Must be between $minTemp and $maxTemp.');
        }
        break;

      case '3':
        securityArmed = !securityArmed;
        print('Security System is now ${securityArmed ? "ARMED" : "DISARMED"}');
        break;

      case '4':
        print('\n--- System Status ---');
        String lightsStatus = lightsOn ? "ON" : "OFF";
        String securityStatus = securityArmed ? "ARMED" : "DISARMED";
        print('Lights: $lightsStatus');
        print('Thermostat: $thermostat°C');
        print('Security System: ${securityStatus.toUpperCase()}');

        if (thermostat % 3 == 0 && thermostat % 5 == 0) {
          print('Perfect Day');
        } else if (thermostat % 3 == 0) {
          print('Cool Day');
        } else if (thermostat % 5 == 0) {
          print('Warm Day');
        }
        break;

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