/*
 *  Copyright 2017 The WebRTC project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */

#include "webrtc/pc/rtptransport.h"

#include "webrtc/base/checks.h"
#include "webrtc/base/copyonwritebuffer.h"
#include "webrtc/p2p/base/packettransportinterface.h"

namespace webrtc {

void RtpTransport::SetRtcpMuxEnabled(bool enable) {
  rtcp_mux_enabled_ = enable;
  MaybeSignalReadyToSend();
}

void RtpTransport::SetRtpPacketTransport(
    rtc::PacketTransportInternal* new_packet_transport) {
  if (new_packet_transport == rtp_packet_transport_) {
    return;
  }
  if (rtp_packet_transport_) {
    rtp_packet_transport_->SignalReadyToSend.disconnect(this);
  }
  if (new_packet_transport) {
    new_packet_transport->SignalReadyToSend.connect(
        this, &RtpTransport::OnReadyToSend);
  }
  rtp_packet_transport_ = new_packet_transport;

  // Assumes the transport is ready to send if it is writable. If we are wrong,
  // ready to send will be updated the next time we try to send.
  SetReadyToSend(false,
                 rtp_packet_transport_ && rtp_packet_transport_->writable());
}

void RtpTransport::SetRtcpPacketTransport(
    rtc::PacketTransportInternal* new_packet_transport) {
  if (new_packet_transport == rtcp_packet_transport_) {
    return;
  }
  if (rtcp_packet_transport_) {
    rtcp_packet_transport_->SignalReadyToSend.disconnect(this);
  }
  if (new_packet_transport) {
    new_packet_transport->SignalReadyToSend.connect(
        this, &RtpTransport::OnReadyToSend);
  }
  rtcp_packet_transport_ = new_packet_transport;

  // Assumes the transport is ready to send if it is writable. If we are wrong,
  // ready to send will be updated the next time we try to send.
  SetReadyToSend(true,
                 rtcp_packet_transport_ && rtcp_packet_transport_->writable());
}

bool RtpTransport::IsWritable(bool rtcp) const {
  rtc::PacketTransportInternal* transport = rtcp && !rtcp_mux_enabled_
                                                ? rtcp_packet_transport_
                                                : rtp_packet_transport_;
  return transport && transport->writable();
}

bool RtpTransport::SendPacket(bool rtcp,
                              const rtc::CopyOnWriteBuffer* packet,
                              const rtc::PacketOptions& options,
                              int flags) {
  rtc::PacketTransportInternal* transport = rtcp && !rtcp_mux_enabled_
                                                ? rtcp_packet_transport_
                                                : rtp_packet_transport_;
  int ret = transport->SendPacket(packet->data<char>(), packet->size(), options,
                                  flags);
  if (ret != static_cast<int>(packet->size())) {
    if (transport->GetError() == ENOTCONN) {
      LOG(LS_WARNING) << "Got ENOTCONN from transport.";
      SetReadyToSend(rtcp, false);
    }
    return false;
  }
  return true;
}

PacketTransportInterface* RtpTransport::GetRtpPacketTransport() const {
  return rtp_packet_transport_;
}

PacketTransportInterface* RtpTransport::GetRtcpPacketTransport() const {
  return rtcp_packet_transport_;
}

RTCError RtpTransport::SetRtcpParameters(const RtcpParameters& parameters) {
  if (rtcp_parameters_.mux && !parameters.mux) {
    LOG_AND_RETURN_ERROR(RTCErrorType::INVALID_STATE,
                         "Disabling RTCP muxing is not allowed.");
  }

  RtcpParameters new_parameters = parameters;

  if (new_parameters.cname.empty()) {
    new_parameters.cname = rtcp_parameters_.cname;
  }

  rtcp_parameters_ = new_parameters;
  return RTCError::OK();
}

RtcpParameters RtpTransport::GetRtcpParameters() const {
  return rtcp_parameters_;
}

RtpTransportAdapter* RtpTransport::GetInternal() {
  return nullptr;
}

void RtpTransport::OnReadyToSend(rtc::PacketTransportInternal* transport) {
  SetReadyToSend(transport == rtcp_packet_transport_, true);
}

void RtpTransport::SetReadyToSend(bool rtcp, bool ready) {
  if (rtcp) {
    rtcp_ready_to_send_ = ready;
  } else {
    rtp_ready_to_send_ = ready;
  }

  MaybeSignalReadyToSend();
}

void RtpTransport::MaybeSignalReadyToSend() {
  bool ready_to_send =
      rtp_ready_to_send_ && (rtcp_ready_to_send_ || rtcp_mux_enabled_);
  if (ready_to_send != ready_to_send_) {
    ready_to_send_ = ready_to_send;
    SignalReadyToSend(ready_to_send);
  }
}

}  // namespace webrtc