/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef mozilla_net_ASpdySession_h

#define mozilla_net_ASpdySession_h

#include "nsAHttpTransaction.h"

#include "prinrval.h"

#include "nsString.h"

class nsISocketTransport;

namespace mozilla { namespace net {

class ASpdySession : public nsAHttpTransaction

{

public:

  ASpdySession() = default;

  virtual ~ASpdySession() = default;

  virtual MOZ_MUST_USE bool

  AddStream(nsAHttpTransaction *, int32_t, bool, nsIInterfaceRequestor *) = 0;

  virtual bool CanReuse() = 0;

  virtual bool RoomForMoreStreams() = 0;

  virtual PRIntervalTime IdleTime() = 0;

  virtual uint32_t ReadTimeoutTick(PRIntervalTime now) = 0;

  virtual void DontReuse() = 0;

  virtual enum SpdyVersion SpdyVersion() = 0;

  static ASpdySession *NewSpdySession(net::SpdyVersion version, nsISocketTransport *, bool);

  virtual bool TestJoinConnection(const nsACString &hostname, int32_t port) = 0;

  virtual bool JoinConnection(const nsACString &hostname, int32_t port) = 0;

  // MaybeReTunnel() is called by the connection manager when it cannot

  // dispatch a tunneled transaction. That might be because the tunnels it

  // expects to see are dead (and we may or may not be able to make more),

  // or it might just need to wait longer for one of them to become free.

  //

  // return true if the session takes back ownership of the transaction from

  // the connection manager.

  virtual bool MaybeReTunnel(nsAHttpTransaction *) = 0;

  virtual void PrintDiagnostics (nsCString &log) = 0;

  bool ResponseTimeoutEnabled() const final {

    return true;

  }

  virtual void SendPing() = 0;

  const static uint32_t kSendingChunkSize = 4095;

  const static uint32_t kTCPSendBufferSize = 131072;

  // This is roughly the amount of data a suspended channel will have to

  // buffer before h2 flow control kicks in.

  const static uint32_t kInitialRwin = 12 * 1024 * 1024; // 12MB

  const static uint32_t kDefaultMaxConcurrent = 100;

  // soft errors are errors that terminate a stream without terminating the

  // connection. In general non-network errors are stream errors as well

  // as network specific items like cancels.

  bool SoftStreamError(nsresult code)

  {

    if (NS_SUCCEEDED(code) || code == NS_BASE_STREAM_WOULD_BLOCK) {

      return false;

    }

    // this could go either way, but because there are network instances of

    // it being a hard error we should consider it hard.

    if (code == NS_ERROR_FAILURE || code == NS_ERROR_OUT_OF_MEMORY) {

      return false;

    }

    if (NS_ERROR_GET_MODULE(code) != NS_ERROR_MODULE_NETWORK) {

      return true;

    }

    // these are network specific soft errors

    return (code == NS_BASE_STREAM_CLOSED || code == NS_BINDING_FAILED ||

            code == NS_BINDING_ABORTED || code == NS_BINDING_REDIRECTED ||

            code == NS_ERROR_INVALID_CONTENT_ENCODING ||

            code == NS_BINDING_RETARGETED || code == NS_ERROR_CORRUPTED_CONTENT);

  }

};

typedef bool (*ALPNCallback) (nsISupports *); // nsISSLSocketControl is typical

// this is essentially a single instantiation as a member of nsHttpHandler.

// It could be all static except using static ctors of XPCOM objects is a

// bad idea.

class SpdyInformation

{

public:

  SpdyInformation();

  ~SpdyInformation() = default;

  static const uint32_t kCount = 1;

  // determine the index (0..kCount-1) of the spdy information that

  // correlates to the npn string. NS_FAILED() if no match is found.

  MOZ_MUST_USE nsresult GetNPNIndex(const nsACString &npnString, uint32_t *result) const;

  // determine if a version of the protocol is enabled for index < kCount

  bool ProtocolEnabled(uint32_t index) const;

  SpdyVersion Version[kCount]; // telemetry enum e.g. SPDY_VERSION_31

  nsCString VersionString[kCount]; // npn string e.g. "spdy/3.1"

  // the ALPNCallback function allows the protocol stack to decide whether or

  // not to offer a particular protocol based on the known TLS information

  // that we will offer in the client hello (such as version). There has

  // not been a Server Hello received yet, so not much else can be considered.

  ALPNCallback ALPNCallbacks[kCount];

};

} // namespace net

} // namespace mozilla

#endif // mozilla_net_ASpdySession_h