import 'dart:io';

void main() {

    bool isLightsOn = false;
    int thermostatTemp = 20;
    bool isSecurityArmed = false;



    While (true) {
        print("\n Welcom to the Smart Home System!");
        print("1.Light|2.Thermostat|3.Security system|4.Status|5.Exit");
        stdout.write("Enter your choice: ");

        string? choice = 
        stdin.readLineSync();
    }
    switch (choice) {
        case "1": 
        isLightsOn = !isLightsOn; // 
        print("Light are now on. ");
        break;


        case "2": 
        stdout.write("Set thermostat temprature (15C - 30C): ");
        
        int? input =
        int.tryParse(stdin.readLineSync() ?? "");

        if (input != null && input >= 15 && input <= 30) {
            thermostatTemp = input;
            print("Modified successfully.");

        } else {
            print("Wrong!value shoulde be (15C - 30C ).");
        }
        break; 

        case "3":
        isSecurityArmed = !
        print("The status of the security system has changed");
        break;
        
        case "4":
        string lightText = (isLightsOn? "ON":"OFF").toUpperCase();
        string securityText = (isSecurityArmed? "ARMED":"DISARMED").toUpperCase();


        string note = "";
        if (thermostatTemp %3 == 0 && thermostatTemp %5 == 0){
            note = "- Perfect Day!";
        } else if (thermostatTemp %3 == 0){
            note = "- Cool Day";
        } else if (thermostatTemp %5 == 0){
            note = "-  Warm Day";
        }
        print("\nSystem Status:");
        print("Light:&lightText");
        print("temp:$thermostatTempC$note");
        print("Security:$securityText");
        break;

        case "5":
        exit(0);

        default:
        print("Exiting the system. ");
              

    }
}