// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
//
// HttpStream provides an abstraction for a basic http streams, http pipelining
// implementations, and SPDY.  The HttpStream subtype is expected to manage the
// underlying transport appropriately.  For example, a non-pipelined HttpStream
// would return the transport socket to the pool for reuse.  SPDY streams on the
// other hand leave the transport socket management to the SpdySession.

#ifndef NET_HTTP_HTTP_STREAM_H_
#define NET_HTTP_HTTP_STREAM_H_

#include "base/basictypes.h"
#include "net/base/completion_callback.h"
#include "net/base/net_export.h"
#include "net/base/upload_progress.h"
#include "net/http/http_stream_base.h"

namespace net {

class IOBuffer;

class NET_EXPORT_PRIVATE HttpStream : public HttpStreamBase {
 public:
  HttpStream() {}
  virtual ~HttpStream() {}

  // Queries the UploadDataStream for its progress (bytes sent).
  virtual UploadProgress GetUploadProgress() const = 0;

  // Returns a new (not initialized) stream using the same underlying
  // connection and invalidates the old stream - no further methods should be
  // called on the old stream.  The caller should ensure that the response body
  // from the previous request is drained before calling this method.  If the
  // subclass does not support renewing the stream, NULL is returned.
  virtual HttpStream* RenewStreamForAuth() = 0;

  // After the response headers have been read and after the response body
  // is complete, this function indicates if more data (either erroneous or
  // as part of the next pipelined response) has been read from the socket.
  virtual bool IsMoreDataBuffered() const = 0;

  // Record histogram of number of round trips taken to download the full
  // response body vs bytes transferred.
  virtual void LogNumRttVsBytesMetrics() const = 0;

 private:
  DISALLOW_COPY_AND_ASSIGN(HttpStream);
};

}  // namespace net

#endif  // NET_HTTP_HTTP_STREAM_H_