chainscript/lib/utils/verifyPDF.js

Client for chainscript.io

'use strict';

exports.__esModule = true;
exports['default'] = verifyPDF;

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { 'default': obj }; }

var _stream = require('stream');

var _multihashes = require('multihashes');

var _multihashes2 = _interopRequireDefault(_multihashes);

var _bs58 = require('bs58');

var _bs582 = _interopRequireDefault(_bs58);

var _invertHash = require('invert-hash');

var _invertHash2 = _interopRequireDefault(_invertHash);

var _objectPath = require('object-path');

var _objectPath2 = _interopRequireDefault(_objectPath);

var _readFromPDF = require('./readFromPDF');

var _readFromPDF2 = _interopRequireDefault(_readFromPDF);

var _hashPDF = require('./hashPDF');

var _hashPDF2 = _interopRequireDefault(_hashPDF);

var _hashFile = require('./hashFile');

var INVERTED_HASH_MAP = _invertHash2['default'](_hashFile.HASH_MAP);

function verifyPDF(input, root, toJson) {
  if (root === undefined) root = 'body.content.hash';

  var hash = undefined;
  var algorithm = undefined;
  var input1 = undefined;
  var input2 = undefined;

  if (typeof input === 'string') {
    input1 = input;
    input2 = input;
  } else {
    input1 = new _stream.PassThrough();
    input2 = new _stream.PassThrough();

    input.pipe(input1);
    input.pipe(input2);
  }

  return _readFromPDF2['default'](input1).then(function (json) {
    if (!json) {
      if (toJson) {
        return { verified: false, wants: null, has: null };
      }

      throw new Error('Failed');
    }

    hash = _objectPath2['default'].get(json, root);
    var buf = new Buffer(_bs582['default'].decode(hash));
    var algorithmName = _multihashes2['default'].decode(buf).name;
    algorithm = INVERTED_HASH_MAP[algorithmName];

    if (typeof algorithm === 'undefined') {
      throw new Error('Unsupported algorithm: ' + algorithmName);
    }

    return _hashPDF2['default'](input2, algorithm, null);
  }).then(function (h) {
    if (hash === h) {
      if (toJson) {
        return { verified: true, wants: hash, has: h };
      }

      return true;
    }

    if (toJson) {
      return { verified: false, wants: hash, has: h };
    }

    throw new Error('Failed');
  });
}

module.exports = exports['default'];