stream.addBytesToWriteWindow(delta)
          }
        }
      }
    }

    override fun ackSettings() {
      // TODO: If we don't get this callback after sending settings to the peer, SETTINGS_TIMEOUT.
    }

    override fun ping(
      ack: Boolean,
      payload1: Int,
      payload2: Int,
    ) {
      if (ack) {
        withLock {
          when (payload1) {