// Copyright (c) 2010 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.

#ifndef NET_SPDY_SPDY_HTTP_STREAM_H_
#define NET_SPDY_SPDY_HTTP_STREAM_H_

#include <list>

#include "base/basictypes.h"
#include "base/ref_counted.h"
#include "base/task.h"
#include "net/base/completion_callback.h"
#include "net/base/net_log.h"
#include "net/http/http_request_info.h"
#include "net/spdy/spdy_protocol.h"
#include "net/spdy/spdy_stream.h"

namespace net {

class HttpResponseInfo;
class IOBuffer;
class SpdySession;
class UploadData;
class UploadDataStream;

// The SpdyHttpStream is a HTTP-specific type of stream known to a SpdySession.
class SpdyHttpStream : public SpdyStream::Delegate {
 public:
  // SpdyHttpStream constructor
  SpdyHttpStream();
  virtual ~SpdyHttpStream();

  SpdyStream* stream() { return stream_.get(); }

  // Initialize stream.  Must be called before calling InitializeRequest().
  int InitializeStream(SpdySession* spdy_session,
                       const HttpRequestInfo& request_info,
                       const BoundNetLog& stream_net_log,
                       CompletionCallback* callback);

  // Initialize request.  Must be called before calling SendRequest().
  // SpdyHttpStream takes ownership of |upload_data|. |upload_data| may be NULL.
  void InitializeRequest(base::Time request_time,
                         UploadDataStream* upload_data);

  const HttpResponseInfo* GetResponseInfo() const;

  // ===================================================
  // Interface for [Http|Spdy]NetworkTransaction to use.

  // Sends the request.
  // |callback| is used when this completes asynchronously.
  // The actual SYN_STREAM packet will be sent if the stream is non-pushed.
  int SendRequest(HttpResponseInfo* response,
                  CompletionCallback* callback);

  // Reads the response headers.  Returns a net error code.
  int ReadResponseHeaders(CompletionCallback* callback);

  // Reads the response body.  Returns a net error code or the number of bytes
  // read.
  int ReadResponseBody(
      IOBuffer* buf, int buf_len, CompletionCallback* callback);

  // Cancels any callbacks from being invoked and deletes the stream.
  void Cancel();

  // Returns the number of bytes uploaded.
  uint64 GetUploadProgress() const;

  // ===================================================
  // SpdyStream::Delegate.

  virtual bool OnSendHeadersComplete(int status);
  virtual int OnSendBody();
  virtual bool OnSendBodyComplete(int status);

  // Called by the SpdySession when a response (e.g. a SYN_REPLY) has been
  // received for this stream.
  // SpdyHttpSession calls back |callback| set by SendRequest or
  // ReadResponseHeaders.
  virtual int OnResponseReceived(const spdy::SpdyHeaderBlock& response,
                                 base::Time response_time,
                                 int status);

  // Called by the SpdySession when response data has been received for this
  // stream.  This callback may be called multiple times as data arrives
  // from the network, and will never be called prior to OnResponseReceived.
  // SpdyHttpSession schedule to call back |callback| set by ReadResponseBody.
  virtual void OnDataReceived(const char* buffer, int bytes);

  // For HTTP streams, no data is sent from the client while in the OPEN state,
  // so OnDataSent is never called.
  virtual void OnDataSent(int length);

  // Called by the SpdySession when the request is finished.  This callback
  // will always be called at the end of the request and signals to the
  // stream that the stream has no more network events.  No further callbacks
  // to the stream will be made after this call.
  // SpdyHttpSession call back |callback| set by SendRequest,
  // ReadResponseHeaders or ReadResponseBody.
  virtual void OnClose(int status);

 private:
  // Call the user callback.
  void DoCallback(int rv);

  void ScheduleBufferedReadCallback();

  // Returns true if the callback is invoked.
  bool DoBufferedReadCallback();
  bool ShouldWaitForMoreBufferedData() const;

  ScopedRunnableMethodFactory<SpdyHttpStream> read_callback_factory_;
  scoped_refptr<SpdyStream> stream_;
  scoped_refptr<SpdySession> spdy_session_;

  // The request to send.
  HttpRequestInfo request_info_;

  scoped_ptr<UploadDataStream> request_body_stream_;

  // |response_info_| is the HTTP response data object which is filled in
  // when a SYN_REPLY comes in for the stream.
  // It is not owned by this stream object, or point to |push_response_info_|.
  HttpResponseInfo* response_info_;

  scoped_ptr<HttpResponseInfo> push_response_info_;

  bool download_finished_;

  // We buffer the response body as it arrives asynchronously from the stream.
  // TODO(mbelshe):  is this infinite buffering?
  std::list<scoped_refptr<IOBufferWithSize> > response_body_;

  CompletionCallback* user_callback_;

  // User provided buffer for the ReadResponseBody() response.
  scoped_refptr<IOBuffer> user_buffer_;
  int user_buffer_len_;

  // Is there a scheduled read callback pending.
  bool buffered_read_callback_pending_;
  // Has more data been received from the network during the wait for the
  // scheduled read callback.
  bool more_read_data_pending_;

  DISALLOW_COPY_AND_ASSIGN(SpdyHttpStream);
};

}  // namespace net

#endif  // NET_SPDY_SPDY_HTTP_STREAM_H_