'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = isBase64;

var _assertString = require('./util/assertString');

var _assertString2 = _interopRequireDefault(_assertString);

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

var notBase64 = /[^A-Z0-9+\/=]/i;

function isBase64(str) {
  (0, _assertString2.default)(str);
  var len = str.length;
  if (!len || len % 4 !== 0 || notBase64.test(str)) {
    return false;
  }
  var firstPaddingChar = str.indexOf('=');
  return firstPaddingChar === -1 || firstPaddingChar === len - 1 || firstPaddingChar === len - 2 && str[len - 1] === '=';
}
module.exports = exports['default'];