import 'dart:io';


void main() {
  const int minTemp = 15;
  const int maxTemp = 30;

  bool lightsOn = false;
  int thermostat = 20;
  String securitySystem = "disarmed";

  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? choice = stdin.readLineSync();

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

      case "2":
        stdout.write("Set thermostat temperature ($minTemp°C - $maxTemp°C): ");
        int? newTemp = int.tryParse(stdin.readLineSync()!);

        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.");
        }
        break;

      case "3":
        securitySystem =
            (securitySystem == "disarmed") ? "armed" : "disarmed";
        print("Security system is now ${securitySystem.toUpperCase()}.");
        break;

      case "4":
        print("\nSystem Status:");
        print("- Lights: ${lightsOn ? "ON" : "OFF"}");

        String dayMessage = "";
        if (thermostat % 3 == 0 && thermostat % 5 == 0) {
          dayMessage = "Perfect Day";
        } else if (thermostat % 3 == 0) {
          dayMessage = "Cool Day";
        } else if (thermostat % 5 == 0) {
          dayMessage = "Warm Day";
        }

        print("- Thermostat: $thermostat°C ${dayMessage.isNotEmpty ? "- $dayMessage" : ""}");
        print("- Security System: ${securitySystem.toUpperCase()}");
        break;

      case "5":
        print("Exiting the system. Goodbye!");
        return;

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