proquints.js

// Proquints JS implementation without needing the DOM
// https://github.com/dsw/proquint
import crypto from "crypto";

export function genquint() {
  const hex = `x${crypto.randomBytes(16).toString("hex")}`;
  try {
    const quint = hex2quint(hex);
    return { hex, quint };
  } catch (e) {
    console.error(e);
  }
}
/** 
Converts quint list (dash separated) of arbitrary length to corresponding hex dump prefixed with x
Quint list must contain pairs of quints to align with 32 bit boundary
*/
export function quint2hex(inp) {
  let ret = "x";
  let remaining = inp;
  while (remaining.length > 0) {
    const current = remaining.substring(0, 11);
    if (
      !current.match(/^[bdfghjklmnprstvzaiou]{5}-[bdfghjklmnprstvzaiou]{5}$/)
    ) {
      throw new Error(`Bad quint format for: ${inp}`);
    }
    if (remaining.length > 12) remaining = remaining.substring(12);
    else remaining = remaining.substring(11);
    let currentHex = quint2uint(current).toString(16);
    while (currentHex.length < 8) currentHex = `0${currentHex}`;
    ret += currentHex;
  }
  return ret;
}

/**
Converts hex dump (x prefixed) to a list of quints. Hex dump must contain leading zeros when necessary.
Hex dump length must by divisible by 8.
*/
export function hex2quint(hex) {
  const sep = "-";
  let ret = "";
  let remaining = hex.substring(1); //skip x
  while (remaining.length > 0) {
    if (remaining.length < 8 && remaining.length % 8 != 0) {
      const message = `Bad hex length: ${remaining.length}`;
      throw new Error(message);
    }
    const current = remaining.substring(0, 8);
    remaining = remaining.substring(8);
    const currentQuint = uint2quint(parseInt(current, 16) >> 0);
    ret += currentQuint;
    if (sep) ret += sep;
  }
  if (ret.endsWith(sep)) ret = ret.substring(0, ret.length - sep.length);
  return ret;
}

//following code is based on original java impl.

const uint2consonant = [
  "b",
  "d",
  "f",
  "g",
  "h",
  "j",
  "k",
  "l",
  "m",
  "n",
  "p",
  "r",
  "s",
  "t",
  "v",
  "z",
];

const uint2vowel = ["a", "i", "o", "u"];

const MASK_FIRST4 = 0xf0000000;
const MASK_FIRST2 = 0xc0000000;

function uint2quint(i) {
  let j = "";
  let quint = "";

  j = i & MASK_FIRST4;
  i <<= 4;
  j >>>= 28;
  quint += uint2consonant[j];
  j = i & MASK_FIRST2;
  i <<= 2;
  j >>>= 30;
  quint += uint2vowel[j];
  j = i & MASK_FIRST4;
  i <<= 4;
  j >>>= 28;
  quint += uint2consonant[j];
  j = i & MASK_FIRST2;
  i <<= 2;
  j >>>= 30;
  quint += uint2vowel[j];
  j = i & MASK_FIRST4;
  i <<= 4;
  j >>>= 28;
  quint += uint2consonant[j];

  quint += "-";

  j = i & MASK_FIRST4;
  i <<= 4;
  j >>>= 28;
  quint += uint2consonant[j];
  j = i & MASK_FIRST2;
  i <<= 2;
  j >>>= 30;
  quint += uint2vowel[j];
  j = i & MASK_FIRST4;
  i <<= 4;
  j >>>= 28;
  quint += uint2consonant[j];
  j = i & MASK_FIRST2;
  i <<= 2;
  j >>>= 30;
  quint += uint2vowel[j];
  j = i & MASK_FIRST4;
  i <<= 4;
  j >>>= 28;
  quint += uint2consonant[j];
  return quint;
}

export function quint2uint(quint) {
  let res = 0;
  let remaining = quint.length;
  let i = 0;
  while (remaining > 0) {
    const c = quint[i++];
    remaining--;
    switch (c) {
      /* consonants */
      case "b":
        res <<= 4;
        res += 0;
        break;
      case "d":
        res <<= 4;
        res += 1;
        break;
      case "f":
        res <<= 4;
        res += 2;
        break;
      case "g":
        res <<= 4;
        res += 3;
        break;

      case "h":
        res <<= 4;
        res += 4;
        break;
      case "j":
        res <<= 4;
        res += 5;
        break;
      case "k":
        res <<= 4;
        res += 6;
        break;
      case "l":
        res <<= 4;
        res += 7;
        break;

      case "m":
        res <<= 4;
        res += 8;
        break;
      case "n":
        res <<= 4;
        res += 9;
        break;
      case "p":
        res <<= 4;
        res += 10;
        break;
      case "r":
        res <<= 4;
        res += 11;
        break;

      case "s":
        res <<= 4;
        res += 12;
        break;
      case "t":
        res <<= 4;
        res += 13;
        break;
      case "v":
        res <<= 4;
        res += 14;
        break;
      case "z":
        res <<= 4;
        res += 15;
        break;

      /* vowels */
      case "a":
        res <<= 2;
        res += 0;
        break;
      case "i":
        res <<= 2;
        res += 1;
        break;
      case "o":
        res <<= 2;
        res += 2;
        break;
      case "u":
        res <<= 2;
        res += 3;
        break;

      /* separators */
      default:
        break;
    }
  }
  return res >>> 0; //the unsigned right shift fixes signed int issue - http://stackoverflow.com/a/17106974/1777150
}