copay/js/models/core/Structure.js

'use strict';

var imports = require('soop').imports();
var preconditions = require('preconditions').singleton();

function Structure() {}

/*
 * Based on https://github.com/maraoz/bips/blob/master/bip-NNNN.mediawiki
 * m / purpose' / cosigner_index / change / address_index
 */
var PURPOSE = 45;
var MAX_NON_HARDENED = 0x80000000 - 1;

var SHARED_INDEX = MAX_NON_HARDENED - 0;
var ID_INDEX = MAX_NON_HARDENED - 1;

var BIP45_PUBLIC_PREFIX = 'm/' + PURPOSE + '\'';
Structure.BIP45_PUBLIC_PREFIX = BIP45_PUBLIC_PREFIX;

Structure.Branch = function(address_index, isChange, cosigner_index) {
  preconditions.shouldBeNumber(address_index);
  preconditions.shouldBeBoolean(isChange);
  var ret = 'm/' +
    (typeof cosigner_index !== 'undefined' ? cosigner_index : SHARED_INDEX) + '/' +
    (isChange ? 1 : 0) + '/' +
    address_index;
  return ret;
};

Structure.FullBranch = function(address_index, isChange, cosigner_index) {
  var sub = Structure.Branch(address_index, isChange, cosigner_index);
  sub = sub.substring(2);
  return BIP45_PUBLIC_PREFIX + '/' + sub;
};

Structure.indicesForPath = function(path) {
  preconditions.shouldBeString(path);
  var s = path.split('/');
  return {
    isChange: s[3] === '1',
    index: parseInt(s[4]),
  };
};

Structure.IdFullBranch = Structure.FullBranch(0, false, ID_INDEX);
Structure.IdBranch = Structure.Branch(0, false, ID_INDEX);
Structure.PURPOSE = PURPOSE;
Structure.MAX_NON_HARDENED = MAX_NON_HARDENED;
Structure.SHARED_INDEX = SHARED_INDEX;
Structure.ID_INDEX = ID_INDEX;

module.exports = require('soop')(Structure);