[2020-01-01 00:00:00] >> 0x00000000     6 SETTINGS
[2020-01-01 00:00:00] >> 0x00000000     4 WINDOW_UPDATE
[2020-01-01 00:00:00] >> 0x00000003    47 HEADERS       END_STREAM|END_HEADERS
[2020-01-01 00:00:00] << 0x00000000     6 SETTINGS
[2020-01-01 00:00:00] << 0x00000000     0 SETTINGS      ACK
[2020-01-01 00:00:00] << 0x00000000     4 WINDOW_UPDATE
[2020-01-01 00:00:00] >> 0x00000000     0 SETTINGS      ACK

  @Test
  fun windowUpdateFrames() {
    assertThat(frameLogWindowUpdate(false, 0, 4, Int.MAX_VALUE.toLong()))
      .isEqualTo(">> 0x00000000     4 WINDOW_UPDATE 2147483647")
    assertThat(frameLogWindowUpdate(true, 101, 4, 1))
      .isEqualTo("<< 0x00000065     4 WINDOW_UPDATE 1")
  }

  @Test
  fun flagOverlapOn0x1() {
    assertThat(frameLog(true, 0, 0, TYPE_SETTINGS, 0x1))

class WindowCounter(
  val streamId: Int,
) {
  /** The total number of bytes consumed. */
  var total: Long = 0L
    private set

  /** The total number of bytes acknowledged by outgoing `WINDOW_UPDATE` frames. */
  var acknowledged: Long = 0L
    private set

  val unacknowledged: Long
    @Synchronized get() = total - acknowledged

  @Synchronized
  fun update(
    total: Long = 0,

  /** Lookup table for valid frame types. */
  private val FRAME_NAMES =
    arrayOf(
      "DATA", "HEADERS", "PRIORITY", "RST_STREAM", "SETTINGS", "PUSH_PROMISE", "PING", "GOAWAY",
      "WINDOW_UPDATE", "CONTINUATION",
    )

  /**
   * Lookup table for valid flags for DATA, HEADERS, CONTINUATION. Invalid combinations are
   * represented in binary.
   */

  /** The total number of bytes produced by the application. */
  var writeBytesTotal = 0L
    internal set

  /** The total number of bytes permitted to be produced by incoming `WINDOW_UPDATE` frame. */
  var writeBytesMaximum: Long = connection.peerSettings.initialWindowSize.toLong()
    internal set

  /** Received headers yet to be [taken][takeHeaders]. */
  private val headersQueue = ArrayDeque<Headers>()

  /** The total number of bytes produced by the application. */
  var writeBytesTotal = 0L
    private set

  /** The total number of bytes permitted to be produced according to `WINDOW_UPDATE` frames. */
  var writeBytesMaximum: Long = peerSettings.initialWindowSize.toLong()
    private set

  internal val socket: Socket = builder.socket
  val writer = Http2Writer(builder.sink, client)