if (code == null || listener == null) {
      return new MockResponse()
          .setResponseCode(404)
          .setBody("unexpected request");
    }

    try {
      OAuthSession session = slackApi.exchangeCode(code, redirectUrl());
      listener.sessionGranted(session);
    } catch (IOException e) {
      return new MockResponse()
          .setResponseCode(400)
          .setBody("code exchange failed: " + e.getMessage());

    if (team != null) {
      builder.addQueryParameter("team", team);
    }

    return builder.build();
  }

  /** See https://api.slack.com/methods/oauth.access. */
  public OAuthSession exchangeCode(String code, HttpUrl redirectUrl) throws IOException {
    HttpUrl url = baseUrl.newBuilder("oauth.access")
        .addQueryParameter("client_id", clientId)
        .addQueryParameter("client_secret", clientSecret)

import okhttp3.Request
import okhttp3.Response
import okhttp3.Route
import okhttp3.internal.connection.RealCall
import okio.Sink
import okio.Source

/** Encodes HTTP requests and decodes HTTP responses. */
interface ExchangeCodec {
  /** The connection or CONNECT tunnel that owns this codec. */
  val carrier: Carrier

  /** Returns an output stream where the request body can be streamed. */
  @Throws(IOException::class)
  fun createRequestBody(

class Http1ExchangeCodec(
  /** The client that configures this stream. May be null for HTTPS proxy tunnels. */
  private val client: OkHttpClient?,
  override val carrier: ExchangeCodec.Carrier,
  private val source: BufferedSource,
  private val sink: BufferedSink,
) : ExchangeCodec {
  private var state = STATE_IDLE
  private val headersReader = HeadersReader(source)

  private val Response.isChunked: Boolean

import okhttp3.Headers
import okhttp3.OkHttpClient
import okhttp3.Protocol
import okhttp3.Request
import okhttp3.Response
import okhttp3.internal.headersContentLength
import okhttp3.internal.http.ExchangeCodec
import okhttp3.internal.http.ExchangeCodec.Carrier
import okhttp3.internal.http.HTTP_CONTINUE
import okhttp3.internal.http.RealInterceptorChain
import okhttp3.internal.http.RequestLine
import okhttp3.internal.http.StatusLine

/**
 * Transmits a single HTTP request and a response pair. This layers connection management and events
 * on [ExchangeCodec], which handles the actual I/O.
 */
class Exchange(
  internal val call: RealCall,
  internal val eventListener: EventListener,
  internal val finder: ExchangeFinder,
  private val codec: ExchangeCodec,
) {
  /** True if the request body need not complete before the response body starts. */

import okhttp3.Protocol
import okhttp3.Request
import okhttp3.Response
import okhttp3.internal.closeQuietly
import okhttp3.internal.connection.RealCall
import okhttp3.internal.discard
import okhttp3.internal.http.ExchangeCodec
import okhttp3.internal.http.HttpMethod
import okhttp3.internal.http.RealResponseBody
import okhttp3.internal.http.promisesBody
import okhttp3.internal.stripBody
import okio.Buffer
import okio.Source

import okhttp3.internal.assertNotHeld
import okhttp3.internal.closeQuietly
import okhttp3.internal.concurrent.TaskRunner
import okhttp3.internal.connection.Locks.withLock
import okhttp3.internal.http.ExchangeCodec
import okhttp3.internal.http.RealInterceptorChain
import okhttp3.internal.http1.Http1ExchangeCodec
import okhttp3.internal.http2.ConnectionShutdownException
import okhttp3.internal.http2.ErrorCode

import okhttp3.internal.closeQuietly
import okhttp3.internal.concurrent.TaskRunner
import okhttp3.internal.connection.Locks.withLock
import okhttp3.internal.connection.RoutePlanner.ConnectResult
import okhttp3.internal.http.ExchangeCodec
import okhttp3.internal.http1.Http1ExchangeCodec
import okhttp3.internal.platform.Platform
import okhttp3.internal.tls.OkHostnameVerifier
import okhttp3.internal.toHostHeader
import okio.BufferedSink

HSPLokhttp3/internal/http2/Http2ExchangeCodec;->createRequestBody(Lokhttp3/Request;J)Lokio/Sink;
HSPLokhttp3/internal/http2/Http2ExchangeCodec;->finishRequest()V
HSPLokhttp3/internal/http2/Http2ExchangeCodec;->getCarrier()Lokhttp3/internal/http/ExchangeCodec$Carrier;