export function mergeTypedArrays(a: any, b: any) {
  // Checks for truthy values on both arrays
  if (!a && !b) throw "Please specify valid arguments for parameters a and b.";

  // Checks for truthy values or empty arrays on each argument
  // to avoid the unnecessary construction of a new array and
  // the type comparison
  if (!b || b.length === 0) return a;
  if (!a || a.length === 0) return b;

  // Make sure that both typed arrays are of the same type
  if (Object.prototype.toString.call(a) !== Object.prototype.toString.call(b))
    throw "The types of the two arguments passed for parameters a and b do not match.";

  var c = new a.constructor(a.length + b.length);
  c.set(a);
  c.set(b, a.length);

  return c;
}

export function uint8arrayToStringMethod(uint8arr: any, callback: (str: any) => void) {
  var bb = new Blob([uint8arr]);
  var f = new FileReader();
  f.onload = function (e) {
    callback(e.target.result);
  };

  f.readAsText(bb);
}


// Convert data url to blob.
function dataURItoBlob(dataURI: string): Blob {
  // convert base64/URLEncoded data component to raw binary data held in a string
  var byteString;
  if (dataURI.split(',')[0].indexOf('base64') >= 0)
    byteString = atob(dataURI.split(',')[1]);
  else
    byteString = unescape(dataURI.split(',')[1]);

  // separate out the mime component
  var mimeString = dataURI.split(',')[0].split(':')[1].split(';')[0];

  // write the bytes of the string to a typed array
  var ia = new Uint8Array(byteString.length);
  for (var i = 0; i < byteString.length; i++) {
    ia[i] = byteString.charCodeAt(i);
  }

  return new Blob([ia], { type: mimeString });
}

export function helloWorld() {
  alert( 'Hello, world!' );
}