private val charset: Charset,
  ) : Reader() {
    private var closed: Boolean = false
    private var delegate: Reader? = null

    @Throws(IOException::class)
    override fun read(
      cbuf: CharArray,
      off: Int,
      len: Int,
    ): Int {
      if (closed) throw IOException("Stream closed")

      val finalDelegate =
        delegate ?: InputStreamReader(
          source.inputStream(),