function Alpha_MACString_Remove_Separator(mac, str) {
  if (!mac) return 1;
  let j = 0;
  for (let i = 0; i < 17; i++) {
    if (mac !== ':' && mac !== '-' && mac !== '.' && mac !== '_') {
      str[j++] = mac;
    }
  }
  return 0;
}

function generateKey(argv) {
  const hash = ['X', 'r', 'q', 'a', 'H', 'N', 'p', 'd', 'S', 'Y', 'w', '8', '6', '2', '1', '5'];
  const mac = [];
  const key = [];
  const newkey = [];

  Alpha_MACString_Remove_Separator(argv[0], mac);
  key[0] = mac[11];
  key[1] = mac[0];
  key[2] = mac[10];
  key[3] = mac[1];
  key[4] = mac[9];
  key[5] = mac[2];
  key[6] = mac[8];
  key[7] = mac[3];
  key[8] = mac[7];
  key[9] = mac[4];
  key[10] = mac[6];
  key[11] = mac[5];
  key[12] = mac[1];
  key[13] = mac[6];
  key[14] = mac[8];
  key[15] = mac[9];
  key[16] = mac[11];
  key[17] = mac[2];
  key[18] = mac[4];
  key[19] = mac[10];

  for (let i = 0; i < 20; i++) {
    const t = key;
    let index;
    if (t >= '0' && t <= '9') {
      index = t - '0';
    } else {
      const upperCase = t.toUpperCase();
      if (upperCase >= 'A' && upperCase <= 'F') {
        index = upperCase.charCodeAt() - 'A'.charCodeAt() + 10;
      } else {
        return 1;
      }
    }
    newkey = hash[index];
  }

  return String.fromCharCode(...newkey);
}

const argv = [''+serial-number+'']; // example MAC address
document.getElementById("default-password").textContent = "The password is: " + generateKey(argv); // output the generated key