import 'dart:io';

const int MIN_TEMP = 15;
const int MAX_TEMP = 30;

void main() {
  bool lightsOn = false;
  int thermostat = 20;
  bool securityArmed = false;

  print('Welcome to the Smart Home Automation CLI!');

  while (true) {
    print('\nChoose an option:');
    print('1. Toggle Lights (on/off)');
    print('2. Set Thermostat (15 - 30 °C)');
    print('3. Arm/Disarm Security System');
    print('4. View System Status');
    print('5. Exit');

    stdout.write('Enter choice (1-5): ');
    String? choice = stdin.readLineSync();

    if (choice == null) {
      print('Invalid input. Try again.');
      continue;
    }

    if (choice == '1') {
      switch (lightsOn) {
        case true:
          lightsOn = false;
          print('Lights turned OFF.');
          break;
        case false:
          lightsOn = true;
          print('Lights turned ON.');
          break;
      }
    } else if (choice == '2') {
      while (true) {
        stdout.write(
          'Enter thermostat temperature (integer °C between $MIN_TEMP and $MAX_TEMP): ',
        );
        String? tempInput = stdin.readLineSync();
        if (tempInput == null) {
          print('Invalid input. Try again.');
          continue;
        }
        int? temp = int.tryParse(tempInput);
        if (temp == null) {
          print('Please enter an integer value.');
          continue;
        }
        if (temp < MIN_TEMP || temp > MAX_TEMP) {
          print('Temperature must be between $MIN_TEMP and $MAX_TEMP.');
          continue;
        }
        thermostat = temp;
        print('Thermostat set to ${thermostat}°C.');
        break;
      }
    } else if (choice == '3') {
      switch (securityArmed) {
        case true:
          securityArmed = false;
          print('Security system DISARMED.');
          break;
        case false:
          securityArmed = true;
          print('Security system ARMED.');
          break;
      }
    } else if (choice == '4') {
      String lightsStatus = lightsOn ? 'ON' : 'OFF';
      String securityStatus = securityArmed ? 'ARMED' : 'DISARMED';

      String dayMsg = '';
      bool by3 = (thermostat % 3 == 0);
      bool by5 = (thermostat % 5 == 0);
      if (by3 && by5) {
        dayMsg = 'Perfect Day';
      } else if (by3) {
        dayMsg = 'Cool Day';
      } else if (by5) {
        dayMsg = 'Warm Day';
      }

      print('\n--- System Status ---');
      print('Lights: $lightsStatus');
      print(
        'Thermostat: ${thermostat}°C ${dayMsg.isNotEmpty ? "- $dayMsg" : ""}',
      );
      print('Security System: ${securityStatus.toUpperCase()}');
      print('---------------------\n');
    } else if (choice == '5') {
      print('Exiting Smart Home CLI. Goodbye!');
      break;
    } else {
      print('Invalid choice. Please select 1-5.');
    }
  }
}