import 'dart:io';

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

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

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

  while (true) {
    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? input = stdin.readLineSync();
    int choice = int.tryParse(input ?? '') ?? 0;

    if (choice == 1) {
      // Toggle lights
      lightsOn = !lightsOn;
      print('Lights are now ${lightsOn ? "ON" : "OFF"}.');
    } else if (choice == 2) {
      // Set thermostat
      stdout.write('Set thermostat temperature ($minTemp°C - $maxTemp°C): ');
      String? tempInput = stdin.readLineSync();
      int? newTemp = int.tryParse(tempInput ?? '');

      if (newTemp == null || newTemp < minTemp || newTemp > maxTemp) {
        print('Invalid temperature! Please enter a value between $minTemp and $maxTemp.');
      } else {
        thermostat = newTemp;
        print('Thermostat set to $thermostat°C.');
      }
    } else if (choice == 3) {
      // Arm/disarm security system
      securityArmed = !securityArmed;
      print('Security system is now ${securityArmed ? "ARMED" : "DISARMED"}.');
    } else if (choice == 4) {
      // View system status
      String lightsStatus = lightsOn ? 'ON' : 'OFF';
      String securityStatus = securityArmed ? 'ARMED' : 'DISARMED';

      // FizzBuzz-like temperature label
      String tempLabel;
      if (thermostat % 3 == 0 && thermostat % 5 == 0) {
        tempLabel = 'Perfect Day';
      } else if (thermostat % 3 == 0) {
        tempLabel = 'Cool Day';
      } else if (thermostat % 5 == 0) {
        tempLabel = 'Warm Day';
      } else {
        tempLabel = '';
      }

      print('\nSystem Status:');
      print('- Lights: $lightsStatus');
      print('- Thermostat: $thermostat°C${tempLabel.isNotEmpty ? " - $tempLabel" : ""}');
      print('- Security System: $securityStatus');
    } else if (choice == 5) {
      print('Exiting the system. Goodbye!');
      break;
    } else {
      print('Invalid choice. Please enter a number between 1 and 5.');
    }
  }
}