convert method

@override Iterable<bool> convert(String data)

Implementation

@override
Iterable<bool> convert(String data) sync* {
  verify(data);
  final String checksum = checkSumModulo10(data);
  final int? pattern = BarcodeMaps.ean5Checksum[checksum.codeUnitAt(0)];

  yield* add(BarcodeMaps.eanStartEan2, 5);

  int index = 0;
  for (final int code in data.codeUnits) {
    final List<int>? codes = BarcodeMaps.ean[code];

    if (codes == null) {
      throw BarcodeException('Unable to encode "${String.fromCharCode(code)}" to $name Barcode');
    }

    if (index >= 1) {
      yield* add(BarcodeMaps.eanCenterEan2, 2);
    }

    yield* add(codes[(pattern! >> index) & 1], 7);
    index++;
  }
}