* Add a header line without any validation. Only appropriate for headers from the remote peer
     * or cache.
     */
    internal fun addLenient(line: String) =
      apply {
        val index = line.indexOf(':', 1)
        when {
          index != -1 -> {
            addLenient(line.substring(0, index), line.substring(index + 1))
          }
          line[0] == ':' -> {

internal fun addHeaderLenient(
  builder: Headers.Builder,
  line: String,
): Headers.Builder = builder.addLenient(line)

internal fun addHeaderLenient(
  builder: Headers.Builder,
  name: String,
  value: String,
): Headers.Builder = builder.addLenient(name, value)

internal fun cacheGet(
  cache: Cache,
  request: Request,
): Response? = cache.get(request)

  }

  /** Reads headers or trailers. */
  fun readHeaders(): Headers {
    val result = Headers.Builder()
    while (true) {
      val line = readLine()
      if (line.isEmpty()) break
      result.addLenient(line)
    }
    return result.build()
  }

  companion object {
    private const val HEADER_LIMIT = 256 * 1024
  }

          networkHeaders[fieldName] == null
        ) {
          result.addLenient(fieldName, value)
        }
      }

      for (index in 0 until networkHeaders.size) {
        val fieldName = networkHeaders.name(index)
        if (!isContentSpecificHeader(fieldName) && isEndToEnd(fieldName)) {
          result.addLenient(fieldName, networkHeaders.value(index))
        }
      }

        if (name == RESPONSE_STATUS_UTF8) {
          statusLine = StatusLine.parse("HTTP/1.1 $value")
        } else if (name !in HTTP_2_SKIPPED_RESPONSE_HEADERS) {
          headersBuilder.addLenient(name, value)
        }
      }
      if (statusLine == null) throw ProtocolException("Expected ':status' header not present")

      return Response.Builder()
        .protocol(protocol)

        val varyHeadersBuilder = Headers.Builder()
        val varyRequestHeaderLineCount = readInt(source)
        for (i in 0 until varyRequestHeaderLineCount) {
          varyHeadersBuilder.addLenient(source.readUtf8LineStrict())
        }
        varyHeaders = varyHeadersBuilder.build()

        val statusLine = StatusLine.parse(source.readUtf8LineStrict())
        protocol = statusLine.protocol

        }

        else -> return CacheStrategy(request, null) // No condition! Make a regular request.
      }

      val conditionalRequestHeaders = request.headers.newBuilder()
      conditionalRequestHeaders.addLenient(conditionName, conditionValue!!)

      val conditionalRequest =
        request.newBuilder()
          .headers(conditionalRequestHeaders.build())
          .build()

  return millis.toInt()
}

internal fun List<Header>.toHeaders(): Headers {
  val builder = Headers.Builder()
  for ((name, value) in this) {
    builder.addLenient(name.utf8(), value.utf8())
  }
  return builder.build()
}

internal fun Headers.toHeaderList(): List<Header> =
  (0 until size).map {
    Header(name(it), value(it))
  }