ifthenpay/lib/check-digits.js

ifthenpay unofficial javascript module

'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.HASH_CALC = undefined;
exports.checkDigits = checkDigits;

var _cutPad = require('./cut-pad');

var _cutPad2 = _interopRequireDefault(_cutPad);

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

var HASH_CALC = exports.HASH_CALC = [51, 73, 17, 89, 38, 62, 45, 53, 15, 50, 5, 49, 24, 81, 76, 27, 90, 9, 30, 3]; /**
                                                                                                                    * PO License
                                                                                                                    * @OWNER: José Moreira
                                                                                                                    * @COPYRIGHTER: José Moreira
                                                                                                                    */

function checkDigits(entity, ref, value) {

  // Arguments validation

  if (typeof entity != 'string' || entity.length !== 5) {
    throw TypeError("entity should be a 5 chars string");
  }

  if (typeof ref != 'string' || ref.length !== 7) {
    throw TypeError("ref should be a 7 chars string");
  }

  if (typeof value != 'number' || value <= 0 || value >= 1000000) {
    throw TypeError("value should be a float between 0 and 1.000.000");
  } else {
    value = (0, _cutPad2.default)(Math.floor(value * 100), 8);
  }

  // Init helper variables

  var chk_string = entity + ref + value;
  var chk_val = 0;

  // Just to be sure...
  if (chk_string.length !== 20) {
    throw new Error("Something went wrong but it shouldn't");
  }

  // Calculate value
  for (var i in HASH_CALC) {
    chk_val += +chk_string[i] * HASH_CALC[i];
  }

  // Return the two check digits
  return (0, _cutPad2.default)(98 - chk_val % 97, 2);
}

exports.default = checkDigits;