class GZipIOSink implements IOSink {
  GZipIOSink(this.sink, this.gzip, {this.encoding = utf8});

  final IOSink sink;

  final GZipCodec gzip;

  @override
  Encoding encoding;

  @override
  void add(List<int> data) {
    sink.add(gzip.encode(data));
  }

  @override
  void addError(Object error, [StackTrace stackTrace]) {
    sink.addError(error, stackTrace);
  }

  @override
  Future<void> addStream(Stream<List<int>> stream) {
    return sink.addStream(stream.transform(gzip.encoder));
  }

  @override
  Future<void> close() {
    return sink.close();
  }

  @override
  Future<void> get done {
    return sink.done;
  }

  @override
  Future<void> flush() {
    return sink.flush();
  }

  @override
  void write(Object obj) {
    add(encoding.encode('$obj'));
  }

  @override
  void writeAll(Iterable<Object> objects, [String separator = '']) {
    write(objects.join(separator));
  }

  @override
  void writeCharCode(int charCode) {}

  @override
  void writeln([Object obj = '']) {
    write('$obj\n');
  }
}