interface FlowControlListener {
  /**
   * Notification that the receiving stream flow control window has changed.
   * [WindowCounter] generally carries the client view of total and acked bytes.
   */
  fun receivingStreamWindowChanged(
    streamId: Int,
    windowCounter: WindowCounter,
    bufferSize: Long,
  )

  /**
   * Notification that the receiving connection flow control window has changed.

   * response body is [closed][ResponseBody]. The recipient of the callback may consume the response
   * body on another thread.
   *
   * Note that transport-layer success (receiving a HTTP response code, headers and body) does not
   * necessarily indicate application-layer success: `response` may still indicate an unhappy HTTP
   * response code like 404 or 500.
   */
  @Throws(IOException::class)

 * limitations under the License.
 */
package okhttp3.internal.http2

/**
 * Settings describe characteristics of the sending peer, which are used by the receiving peer.
 * Settings are [connection][Http2Connection] scoped.
 */
class Settings {
  /** Bitfield of which flags that values. */
  private var set: Int = 0

  /** Flag values. */

   * This was misleading for tracing because it was too early.
   */
  open fun responseHeadersStart(call: Call) {
  }

  /**
   * Invoked immediately after receiving response headers.
   *
   * This method is always invoked after [responseHeadersStart].
   *
   * @param response the response received over the network. It is an error to access the body of
   *     this response.

import java.io.IOException
import okhttp3.internal.authenticator.JavaNetAuthenticator

/**
 * Performs either **preemptive** authentication before connecting to a proxy server, or
 * **reactive** authentication after receiving a challenge from either an origin web server or proxy
 * server.
 *
 * ## Preemptive Authentication
 *
 * To make HTTPS calls using an HTTP proxy server OkHttp must first negotiate a connection with

   * leaking resources callers must [close the response body][ResponseBody] or the response.
   *
   * Note that transport-layer success (receiving a HTTP response code, headers and body) does not
   * necessarily indicate application-layer success: `response` may still indicate an unhappy HTTP
   * response code like 404 or 500.
   *

   *
   * This method returns false unless it is overridden by a subclass.
   *
   * ### Duplex Transmission
   *
   * With regular HTTP calls the request always completes sending before the response may begin
   * receiving. With duplex the request and response may be interleaved! That is, request body bytes
   * may be sent after response headers or body bytes have been received.
   *

 * registration. It is not a general-purpose publish-subscribe system, nor is it intended
 * for interprocess communication.
 *
 * <h2>Receiving Events</h2>
 *
 * <p>To receive events, an object should:
 *
 * <ol>
 *   <li>Expose a public method, known as the <i>event subscriber</i>, which accepts a single
 *       argument of the type of event desired;

    /**
     * Configures this request's body to be compressed when it is transmitted. This also adds the
     * 'Content-Encoding: gzip' header.
     *
     * Only use this method if you have prior knowledge that the receiving server supports
     * gzip-compressed requests.
     *
     * It is an error to call this multiple times on the same instance.
     *

    // retry, we return true and try a new route.
    return true
  }

  /**
   * Figures out the HTTP request to make in response to receiving [userResponse]. This will
   * either add authentication headers, follow redirects or handle a client request timeout. If a
   * follow-up is either unnecessary or not applicable, this returns null.
   */