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? choice = stdin.readLineSync();

    if (choice == '1') {
      lightsOn = !lightsOn;
      print("Lights are now ${lightsOn ? 'ON' : 'OFF'}.");
    } else if (choice == '2') {
      stdout.write("Set thermostat temperature ($minTemp℃ - $maxTemp℃): ");
      int? temp = int.tryParse(stdin.readLineSync() ?? '');
      if (temp != null && temp >= minTemp && temp <= maxTemp) {
        thermostat = temp;
        print("Thermostat set to $thermostat℃.");
      } else {
        print("Invalid temperature. Please enter a value between $minTemp and $maxTemp.");
      }
    } else if (choice == '3') {
      securityArmed = !securityArmed;
      print("Security System is now ${securityArmed ? 'ARMED' : 'DISARMED'}.");
    } else if (choice == '4') {
      print("\nSystem Status:");
      print("- Lights: ${lightsOn ? 'ON' : 'OFF'}");
      String dayType = '';
      if (thermostat % 3 == 0 && thermostat % 5 == 0) {
        dayType = ' - Perfect Day';
      } else if (thermostat % 3 == 0) {
        dayType = ' - Cool Day';
      } else if (thermostat % 5 == 0) {
        dayType = ' - Warm Day';
      }
      print("- Thermostat: $thermostat℃$dayType");
      print("- Security System: ${securityArmed ? 'ARMED' : 'DISARMED'}");
    } else if (choice == '5') {
      print("Exiting the system. Goodbye!");
      break;
    } else {
      print("Invalid choice. Please try again.");
    }
  }
}