/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 et sw=2 tw=80: */
/* 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/. */

// Original author: ekr@rtfm.com

#include "logging.h"
#include "nspr.h"
#include "prlock.h"

#include "nsNetCID.h"
#include "nsIComponentManager.h"
#include "nsComponentManagerUtils.h"
#include "nsIComponentRegistrar.h"
#include "nsIEventTarget.h"
#include "nsIIOService.h"
#include "nsIServiceManager.h"
#include "nsISocketTransportService.h"
#include "nsServiceManagerUtils.h"

#include "transportflow.h"
#include "transportlayerloopback.h"

namespace mozilla {

MOZ_MTLOG_MODULE("mtransport")

nsresult TransportLayerLoopback::Init() {
  timer_ = do_CreateInstance(NS_TIMER_CONTRACTID);
  MOZ_ASSERT(timer_);
  if (!timer_)
    return NS_ERROR_FAILURE;

  nsresult rv;
  target_ = do_GetService(NS_SOCKETTRANSPORTSERVICE_CONTRACTID, &rv);
  MOZ_ASSERT(NS_SUCCEEDED(rv));
  if (!NS_SUCCEEDED(rv))
    return rv;

  timer_->SetTarget(target_);

  packets_lock_ = PR_NewLock();
  MOZ_ASSERT(packets_lock_);
  if (!packets_lock_)
    return NS_ERROR_FAILURE;

  deliverer_ = new Deliverer(this);

  timer_->InitWithCallback(deliverer_, 100, nsITimer::TYPE_REPEATING_SLACK);

  return NS_OK;
}

// Connect to the other side
void TransportLayerLoopback::Connect(TransportLayerLoopback* peer) {
  peer_ = peer;

  TL_SET_STATE(TS_OPEN);
}

TransportResult
TransportLayerLoopback::SendPacket(const unsigned char *data, size_t len) {
  MOZ_MTLOG(ML_DEBUG, LAYER_INFO << "SendPacket(" << len << ")");

  if (!peer_) {
    MOZ_MTLOG(ML_ERROR, "Discarding packet because peer not attached");
    return TE_ERROR;
  }

  nsresult res = peer_->QueuePacket(data, len);
  if (!NS_SUCCEEDED(res))
    return TE_ERROR;

  return static_cast<TransportResult>(len);
}

nsresult TransportLayerLoopback::QueuePacket(const unsigned char *data,
                                         size_t len) {
  MOZ_ASSERT(packets_lock_);

  PR_Lock(packets_lock_);

  if (combinePackets_ && !packets_.empty()) {
    QueuedPacket *packet = packets_.front();
    packets_.pop();

    MOZ_MTLOG(ML_DEBUG, LAYER_INFO << " Enqueuing combined packets of length " << packet->len() << " and " << len);
    packets_.push(new QueuedPacket());
    packets_.back()->Assign(packet->data(), packet->len(),
                            data, len);
  } else {
    MOZ_MTLOG(ML_DEBUG, LAYER_INFO << " Enqueuing packet of length " << len);
    packets_.push(new QueuedPacket());
    packets_.back()->Assign(data, len);
  }

  PRStatus r = PR_Unlock(packets_lock_);
  MOZ_ASSERT(r == PR_SUCCESS);
  if (r != PR_SUCCESS)
    return NS_ERROR_FAILURE;

  return NS_OK;
}


void TransportLayerLoopback::DeliverPackets() {
  while (!packets_.empty()) {
    QueuedPacket *packet = packets_.front();
    packets_.pop();

    MOZ_MTLOG(ML_DEBUG, LAYER_INFO << " Delivering packet of length " <<
         packet->len());
    SignalPacketReceived(this, packet->data(), packet->len());

    delete packet;
  }
}

NS_IMPL_ISUPPORTS(TransportLayerLoopback::Deliverer, nsITimerCallback)

NS_IMETHODIMP TransportLayerLoopback::Deliverer::Notify(nsITimer *timer) {
  if (!layer_)
    return NS_OK;

  layer_->DeliverPackets();

  return NS_OK;
}
}  // close namespace