import 'dart:io';

void main() {
  // Final/Const variables
  const int minTemp = 15;
  const int maxTemp = 30;

  // Initial device states
  bool lightsOn = false;
  int thermostat = 20;
  String securitySystem = "disarmed";

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

  bool isRunning = true;

  while (isRunning) {
    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("\nEnter your choice: ");
    String? choice = stdin.readLineSync();

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

      case '2':
        // Set thermostat temperature
        stdout.write(
            "Set thermostat temperature ($minTemp°C - $maxTemp°C): ");
        String? inputTemp = stdin.readLineSync();

        if (inputTemp != null) {
          int? newTemp = int.tryParse(inputTemp);

          if (newTemp == null) {
            print("Invalid input! Please enter a valid number.");
          } else if (newTemp < minTemp || newTemp > maxTemp) {
            print(
                "Temperature must be between $minTemp°C and $maxTemp°C.");
          } else {
            thermostat = newTemp;
            print("Thermostat set to $thermostat°C.");
          }
        }
        break;

      case '3':
        // Arm/disarm security system
        if (securitySystem == "disarmed") {
          securitySystem = "armed";
        } else {
          securitySystem = "disarmed";
        }
        print(
            "Security system is now ${securitySystem.toUpperCase()}.");
        break;

      case '4':
        // View system status
        print("\nSystem Status:");

        // FizzBuzz-like logic for temperature
        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("- Lights: ${lightsOn ? "ON" : "OFF"}");
        print("- Thermostat: $thermostat°C"
            "${dayMessage.isNotEmpty ? " - $dayMessage" : ""}");
        print("- Security System: ${securitySystem.toUpperCase()}");
        break;

      case '5':
        print("Exiting the system. Goodbye!");
        isRunning = false;
        break;

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