index.js

"use strict";

module.exports = {
  encrypt: (text, salt) => {
    const textToChars = (text) => text.split("").map((c) => c.charCodeAt(0));
    const byteHex = (n) => ("0" + Number(n).toString(16)).substr(-2);
    const applySaltToChar = (code) =>
      textToChars(salt).reduce((a, b) => a ^ b, code);

    return text
      .split("")
      .map(textToChars)
      .map(applySaltToChar)
      .map(byteHex)
      .join("");
  },
  decrypt: (text, salt) => {
    const textToChars = (text) => text.split("").map((c) => c.charCodeAt(0));
    const applySaltToChar = (code) =>
      textToChars(salt).reduce((a, b) => a ^ b, code);
    return text
      .match(/.{1,2}/g)
      .map((hex) => parseInt(hex, 16))
      .map(applySaltToChar)
      .map((charCode) => String.fromCharCode(charCode))
      .join("");
  },
};