signal-desktop/libtextsecure/helpers.js

/* global window, dcodeIO */

/* eslint-disable no-proto, no-restricted-syntax, guard-for-in */

window.textsecure = window.textsecure || {};

/** *******************************
 *** Type conversion utilities ***
 ******************************** */
// Strings/arrays
// TODO: Throw all this shit in favor of consistent types
// TODO: Namespace
const StaticByteBufferProto = new dcodeIO.ByteBuffer().__proto__;
const StaticArrayBufferProto = new ArrayBuffer().__proto__;
const StaticUint8ArrayProto = new Uint8Array().__proto__;
function getString(thing) {
  if (thing === Object(thing)) {
    if (thing.__proto__ === StaticUint8ArrayProto)
      return String.fromCharCode.apply(null, thing);
    if (thing.__proto__ === StaticArrayBufferProto)
      return getString(new Uint8Array(thing));
    if (thing.__proto__ === StaticByteBufferProto)
      return thing.toString('binary');
  }
  return thing;
}

function getStringable(thing) {
  return (
    typeof thing === 'string' ||
    typeof thing === 'number' ||
    typeof thing === 'boolean' ||
    (thing === Object(thing) &&
      (thing.__proto__ === StaticArrayBufferProto ||
        thing.__proto__ === StaticUint8ArrayProto ||
        thing.__proto__ === StaticByteBufferProto))
  );
}

// Number formatting utils
window.textsecure.utils = (() => {
  const self = {};
  self.unencodeNumber = number => number.split('.');
  self.isNumberSane = number =>
    number[0] === '+' && /^[0-9]+$/.test(number.substring(1));

  /** ************************
   *** JSON'ing Utilities ***
   ************************* */
  function ensureStringed(thing) {
    if (getStringable(thing)) return getString(thing);
    else if (thing instanceof Array) {
      const res = [];
      for (let i = 0; i < thing.length; i += 1)
        res[i] = ensureStringed(thing[i]);
      return res;
    } else if (thing === Object(thing)) {
      const res = {};
      for (const key in thing) res[key] = ensureStringed(thing[key]);
      return res;
    } else if (thing === null) {
      return null;
    }
    throw new Error(`unsure of how to jsonify object of type ${typeof thing}`);
  }

  self.jsonThing = thing => JSON.stringify(ensureStringed(thing));

  return self;
})();