@itslanguage/api/utils/index.js

The JavaScript API SDK for ITSLanguage.

import "core-js/modules/es.array.iterator";
import "core-js/modules/es.array-buffer.slice";
import "core-js/modules/es.promise";
import "core-js/modules/es.typed-array.uint8-array";
import "core-js/modules/es.typed-array.to-locale-string";

/**
 * Some all-round re-usable utilities.
 *
 * @module api/utils
 */

/**
 * Convert the given ArrayBuffer to a base64 encoded string.
 *
 * @param {ArrayBuffer} data - The data to transform to base64.
 *
 * @returns {string} - The base64 encoded data.
 */
export function dataToBase64(data) {
  // eslint-disable-line import/prefer-default-export
  var binary = '';
  var bytes = new Uint8Array(data);
  var len = bytes.byteLength;

  for (var i = 0; i < len; i += 1) {
    binary += String.fromCharCode(bytes[i]);
  }

  return window.btoa(binary);
}
/**
 * Async function to convert a Blob to an ArrayBuffer.
 * @param {Blob} blob - The blob to read as ArrayBuffer
 * @returns {Promise}
 */

export function asyncBlobToArrayBuffer(blob) {
  return new Promise((resolve, reject) => {
    var fileReader = new FileReader();
    fileReader.addEventListener('loadend', () => {
      resolve(fileReader.result);
    });
    fileReader.addEventListener('error', () => {
      fileReader.abort();
      reject(fileReader.error);
    });
    fileReader.readAsArrayBuffer(blob);
  });
}
/**
 * A Cheap test to check if the provided audio file has just the header, or that
 * it can be assumed to be "audio". The mimeType is used to do make a best
 * guess. Currently only WAV is supported.
 *
 * @param {number} filesize - Size of the file to check.
 * @param {string} mimeType - Type of the provided blob.
 * @returns {boolean} - Has audio.
 */

export function checkAudioIsNotEmpty(filesize, mimeType) {
  var result;

  switch (mimeType) {
    case 'audio/wav':
      result = filesize > 44;
      break;

    default:
      result = filesize > 0;
  }

  return result;
}