Decode Syrapt0r's "my final note.txt" file by bitshifting it. See: http://code17.wikia.com

decoder.js

"use strict";

let path = require("path");
let fs   = require("fs");

////////////////////////////////
//----------------------------//
// Copyright (c) 2018 NullDev //
//----------------------------//
////////////////////////////////

let args = process.argv.slice(2);

if (args.length <= 0){
    console.log("\nNo File!\n\Usage:\nnode decoder.js /path/to/file.txt\n");
    process.exit(1);
}

let filePath = path.resolve(args[0]);

let byteArray = function(binpath){
    let fileData = fs.readFileSync(binpath).toString("hex");
    let result = [];
    for (var i = 0; i < fileData.length; i += 2) result.push(fileData[i] + fileData[i + 1]);
    return result;
}

let bytes = byteArray(filePath);
let encoded = [];
let stringArr = [];

for (var i = 0; i < bytes.length; i++){
    let value = parseInt(bytes[i], 16) + 50;
    encoded[i] = value % 256;
    stringArr[i] = String.fromCharCode(encoded[i]);
}
    
let text = stringArr.join("");

fs.writeFileSync(path.join(__dirname, "output.txt"), text);