import 'dart:io';

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

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

  bool isRunning = true;

  print("      ===  Assalamualaikum  ===");
  print("===  Smart home automation system  ===");
  while (isRunning) {
    print("\nChoose an option:");
    print("1. Toggle Lights");
    print("2. Set Thermostat");
    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 == null) {
      print("Invalid input.");
      continue;
    }

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

      case "2":
        
        stdout.write("Enter temperature ($minTemp - $maxTemp °C): ");
        String? tempInput = stdin.readLineSync();

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

          if (newTemp != null &&
              newTemp >= minTemp &&
              newTemp <= maxTemp) {
            thermostat = newTemp;
            print("Thermostat set to $thermostat°C.");
          } else {
            print("Invalid temperature. Please enter a value between $minTemp and $maxTemp.");
          }
        }
        break;

      case "3":
        
        if (securityStatus == "disarmed") {
          securityStatus = "armed";
        } else {
          securityStatus = "disarmed";
        }

        print("Security system is now ${securityStatus.toUpperCase()}.");
        break;

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

        
        if (thermostat % 3 == 0 && thermostat % 5 == 0) {
          print("Perfect Day 🌟 ($thermostat°C)");
        } else if (thermostat % 3 == 0) {
          print("Cool Day ❄ ($thermostat°C)");
        } else if (thermostat % 5 == 0) {
          print("Warm Day ☀ ($thermostat°C)");
        }

        break;

      case "5":

        print("Exiting Smart Home System...Assalamualaikum ");
        isRunning = false;
        break;

      default:
        print("Invalid choice. Please select from 1 to 5.");
    }
  }}