function randomDice(seed, failPercent = 5) { // fail percent -> dice out of table
  percentSeed = seed.slice(0, 4);
  percentInt = parseInt(percentSeed, 16);
  percent = percentInt % 100;
  if (percent <= failPercent) {
    return 0;
  }

  diceInt = parseInt(seed, 16);
  return 1 + (diceInt % 6);
}

function throwDice(salt, msg) {
  const hmac = crypto.createHmac("sha256", salt);
  hmac.update(msg);
  seed = hmac.digest("hex");
  console.log(seed);

  seed1 = seed.slice(0, 10);
  seed2 = seed.slice(10, 20);
  seed3 = seed.slice(20, 30);

  dice1 = randomDice(seed1);
  dice2 = randomDice(seed2);
  dice3 = randomDice(seed3);

  return [dice1, dice2, dice3];
}