import 'dart:io';

void main() {
  // System State Variables
  bool lightsOn = false;
  int thermostatTemp = 20; // Default temp
  bool isArmed = false;
  bool running = true;

  print('Welcome to the Smart Home System!');

  while (running) {
    print('\nPlease 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('Enter your choice: ');

    String? choice = stdin.readLineSync();

    switch (choice) {
      case '1':
        lightsOn = !lightsOn;
        print('Lights are now ${lightsOn ? "ON" : "OFF"}.');
        break;
      case '2':
        stdout.write('Set thermostat temperature (15°C - 30°C): ');
        String? tempInput = stdin.readLineSync();
        int? newTemp = int.tryParse(tempInput ?? '');
        if (newTemp != null && newTemp >= 15 && newTemp <= 30) {
          thermostatTemp = newTemp;
          print('Thermostat set to $thermostatTemp°C.');
        } else {
          print('Invalid temperature. Please enter a value between 15 and 30.');
        }
        break;
      case '3':
        isArmed = !isArmed;
        print('Security System ${isArmed ? "ARMED" : "DISARMED"}.');
        break;
      case '4':
        String tempContext = (thermostatTemp > 24) ? "Warm Day" : "Comfortable";
        print('\nSystem Status:');
        print('- Lights: ${lightsOn ? "ON" : "OFF"}');
        print('- Thermostat: $thermostatTemp°C - $tempContext');
        print('- Security System: ${isArmed ? "ARMED" : "DISARMED"}');
        break;
      case '5':
        print('Exiting the system. Goodbye!');
        running = false;
        break;
      default:
        print('Invalid choice, please try again.');
    }
  }
}