OkHttp Brotli Implementation
============================

This module is an implementation of [Brotli][1] compression.
It enables Brotli support in addition to tranparent Gzip support,
provided Accept-Encoding is not set previously.  Modern web servers
must choose to return Brotli responses.  n.b. It is not used for
sending requests.

```java
OkHttpClient client = new OkHttpClient.Builder()
  .addInterceptor(BrotliInterceptor.INSTANCE)
  .build();

OkHttp Zstandard (zstd) Integration
===================================

This module enables [Zstandard (zstd)][1] response compression in addition to Gzip, as long as
the `Accept-Encoding` header is not otherwise set. Web servers must be configured to return zstd
responses.

Note that zstd is not used for sending requests.

```java
OkHttpClient client = new OkHttpClient.Builder()
  .addInterceptor(ZstdInterceptor.INSTANCE)
  .build();
```

import okhttp3.Gzip

/**
 * Transparent Brotli response support.
 *
 * Adds Accept-Encoding: br to request and checks (and strips) for Content-Encoding: br in
 * responses.  n.b. this replaces the transparent gzip compression in BridgeInterceptor.
 */

   *
   * [rfc_7230]: https://tools.ietf.org/html/rfc7230
   */
  HTTP_1_1("http/1.1"),

  /**
   * Chromium's binary-framed protocol that includes header compression, multiplexing multiple
   * requests on the same socket, and server-push. HTTP/1.1 semantics are layered on SPDY/3.
   *
   * Current versions of OkHttp do not support this protocol.
   */

fields must be used instead.

[ZIP specification]: https://support.pkware.com/pkzip/appnote
*/
package zip

import (
	"io/fs"
	"path"
	"time"
)

// Compression methods.
const (
	Store   uint16 = 0 // no compression
	Deflate uint16 = 8 // DEFLATE compressed
)

const (
	fileHeaderSignature      = 0x04034b50
	directoryHeaderSignature = 0x02014b50
	directoryEndSignature    = 0x06054b50

OkHttp may add headers that are absent from the original request, including `Content-Length`, `Transfer-Encoding`, `User-Agent`, `Host`, `Connection`, and `Content-Type`. It will add an `Accept-Encoding` header for transparent response compression unless the header is already present. If you’ve got cookies, OkHttp will add a `Cookie` header with them.

	// into an SSE-S3 request. If enabled a valid, non-empty KMS
	// configuration must be present.
	globalAutoEncryption bool

	// Is compression enabled?
	globalCompressConfigMu sync.Mutex
	globalCompressConfig   compress.Config

	// Some standard object extensions which we strictly dis-allow for compression.
	standardExcludeCompressExtensions = []string{".gz", ".bz2", ".rar", ".zip", ".7z", ".xz", ".mp4", ".mkv", ".mov", ".jpg", ".png", ".gif"}

  var i = pos
  while (i < limit) {
    if (b == address.size) return null // Too many groups.

    // Read a delimiter.
    if (i + 2 <= limit && input.startsWith("::", startIndex = i)) {
      // Compression "::" delimiter, which is anywhere in the input, including its prefix.
      if (compress != -1) return null // Multiple "::" delimiters.
      i += 2
      b += 2
      compress = b
      if (i == limit) break

/**
 * Transparent Compressed response support.
 *
 * The algorithm map will be turned into a heading such as "Accept-Encoding: br, gzip"
 *
 * If [algorithms] is empty this interceptor has no effect. To disable compression set
 * a specific "Accept-Encoding: identity" or similar.
 *
 * See https://developer.mozilla.org/en-US/docs/Web/HTTP/Reference/Headers/Accept-Encoding
 */
open class CompressionInterceptor(

	// ErrIncompatibleEncryptionWithCompression indicates that both data compression and SSE-C not allowed at the same time
	ErrIncompatibleEncryptionWithCompression = Errorf("Server side encryption specified with SSE-C with compression not allowed")

	// ErrInvalidEncryptionKeyID returns error when KMS key id contains invalid characters