Although needs minor tweak, I managed to write a command-line Rock, Paper & Scissors dart game.

rock_paper_scissors.dart

import 'dart:io';
import 'dart:math';

enum Options { r, p, s }

void main() {
  // call func
  rockPaperScissors();
}

void rockPaperScissors() {
  stdout.write('Rock, Paper or Scissors? (r/p/s): ');
  final playerInput = stdin.readLineSync();
  List<Options> options = Options.values;
  final aiInput = options[Random().nextInt(3)].name.toString();
  print('You chose: $playerInput');
  print('AI chose: $aiInput');

  if (!(playerInput == 'q')) {
    // 'q' was not pressed
    // compare choices
    if (playerInput == aiInput) {
      // draw
      print('Draw!');
    } else {
      // not equal
      if ((playerInput == 'r' && aiInput == 'p') ||
          (playerInput == 'p' && aiInput == 'r')) {
        // rock vs paper
        print('paper wins!');
      } else if ((playerInput == 'r' && aiInput == 's') ||
          (playerInput == 's' && aiInput == 'r')) {
        // rock vs scissors
        print('rock wins!');
      } else if ((playerInput == 's' && aiInput == 'p') ||
          (playerInput == 'p' && aiInput == 's')) {
        // scissors vs paper
        print('scissors wins!');
      } else {
        print('Invalid input');
      }
    }
    // recursion
    rockPaperScissors();
  } else {
    // 'q' was pressed
    print('Exit!');
  }
}