* val interceptor = Interceptor { chain: Interceptor.Chain ->
     *     chain.proceed(chain.request())
     * }
     * ```
     */
    inline operator fun invoke(crossinline block: (chain: Chain) -> Response): Interceptor = Interceptor { block(it) }
  }

  interface Chain {
    fun request(): Request

    @Throws(IOException::class)
    fun proceed(request: Request): Response

    /**

   */
  fun onFailure(
    call: Call,
    e: IOException,
  )

  /**
   * Called when the HTTP response was successfully returned by the remote server. The callback may
   * proceed to read the response body with [Response.body]. The response is still live until its
   * response body is [closed][ResponseBody]. The recipient of the callback may consume the response
   * body on another thread.
   *

    override fun intercept(chain: Interceptor.Chain): Response {
      val level = this.level

      val request = chain.request()
      if (level == Level.NONE) {
        return chain.proceed(request)
      }

      val logBody = level == Level.BODY
      val logHeaders = logBody || level == Level.HEADERS

      val requestBody = request.body

      val connection = chain.connection()

        "network interceptor $interceptor must call proceed() exactly once",
      )
    }
  }

  @Test
  fun networkInterceptorsCannotCallProceedMultipleTimes() {
    server.enqueue(MockResponse())
    server.enqueue(MockResponse())
    val interceptor =
      Interceptor { chain: Interceptor.Chain ->
        chain.proceed(chain.request())
        chain.proceed(chain.request())
      }
    client =

        readTimeoutMillis = client.readTimeoutMillis,
        writeTimeoutMillis = client.writeTimeoutMillis,
      )

    var calledNoMoreExchanges = false
    try {
      val response = chain.proceed(originalRequest)
      if (isCanceled()) {
        response.closeQuietly()
        throw IOException("Canceled")
      }
      return response
    } catch (e: IOException) {
      calledNoMoreExchanges = true

  }

  override fun call(): Call = call

  override fun request(): Request = request

  @Throws(IOException::class)
  override fun proceed(request: Request): Response {
    check(index < interceptors.size)

    calls++

    if (exchange != null) {
      check(exchange.finder.routePlanner.sameHostAndPort(request.url)) {

    val realChain = chain as RealInterceptorChain
    val exchange = realChain.call.initExchange(realChain)
    val connectedChain = realChain.copy(exchange = exchange)
    return connectedChain.proceed(realChain.request)
  }

class UppercaseResponseInterceptor : Interceptor {
  @Throws(IOException::class)
  override fun intercept(chain: Chain): Response {
    return uppercaseResponse(chain.proceed(chain.request()))
  }

  private fun uppercaseResponse(response: Response): Response {
    val uppercaseBody: ResponseBody =
      object : ForwardingResponseBody(response.body) {

    assertThat(idle.get()).isFalse()
    val ready = CountDownLatch(1)
    val proceed = CountDownLatch(1)
    client =
      client.newBuilder()
        .addInterceptor(
          Interceptor { chain: Interceptor.Chain ->
            ready.countDown()
            try {
              proceed.await(5, TimeUnit.SECONDS)
            } catch (e: InterruptedException) {
              throw RuntimeException(e)

/** Rewrites the request body sent to the server to be all uppercase.  */
class UppercaseRequestInterceptor : Interceptor {
  @Throws(IOException::class)
  override fun intercept(chain: Chain): Response {
    return chain.proceed(uppercaseRequest(chain.request()))
  }

  /** Returns a request that transforms `request` to be all uppercase.  */
  private fun uppercaseRequest(request: Request): Request {
    val uppercaseBody: RequestBody =