/*
 * libjingle
 * Copyright 2011, Google Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *  1. Redistributions of source code must retain the above copyright notice,
 *     this list of conditions and the following disclaimer.
 *  2. Redistributions in binary form must reproduce the above copyright notice,
 *     this list of conditions and the following disclaimer in the documentation
 *     and/or other materials provided with the distribution.
 *  3. The name of the author may not be used to endorse or promote products
 *     derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <map>
#include <string>
#include <utility>

#include "talk/app/webrtc/audiotrackimpl.h"
#include "talk/app/webrtc/mediastreamimpl.h"
#include "talk/app/webrtc/peerconnectionsignaling.h"
#include "talk/app/webrtc/sessiondescriptionprovider.h"
#include "talk/app/webrtc/streamcollectionimpl.h"
#include "talk/app/webrtc/videotrackimpl.h"
#include "talk/base/gunit.h"
#include "talk/base/scoped_ptr.h"
#include "talk/base/thread.h"
#include "talk/session/phone/channelmanager.h"

static const char kStreamLabel1[] = "local_stream_1";
static const char kStreamLabel2[] = "local_stream_2";
static const char kAudioTrackLabel1[] = "local_audio_1";
static const char kAudioTrackLabel2[] = "local_audio_2";
static const char kVideoTrackLabel1[] = "local_video_1";

namespace webrtc {

typedef std::map<std::string, talk_base::scoped_refptr<MediaStreamInterface> >
    MediaStreamMap;
typedef std::pair<std::string, talk_base::scoped_refptr<MediaStreamInterface> >
    RemotePair;

// MockSignalingObserver implements functions for listening all signals from a
// PeerConnectionSignaling instance.
// The method AnswerPeer can be used to forward messages from one
// PeerConnectionSignaling instance to another.
class MockSignalingObserver : public sigslot::has_slots<> {
 public:
  MockSignalingObserver()
      : last_error_(-1),  // Initialize last_error_ to unused error code.
        state_(PeerConnectionSignaling::kInitializing),
        remote_peer_(NULL) {
  }

  virtual ~MockSignalingObserver() {}

  // New remote stream have been discovered.
  virtual void OnRemoteStreamAdded(MediaStreamInterface* remote_stream) {
    EXPECT_EQ(MediaStreamInterface::kLive, remote_stream->ready_state());
    remote_media_streams_.insert(RemotePair(remote_stream->label(),
                                            remote_stream));
  }

  // Remote stream is no longer available.
  virtual void OnRemoteStreamRemoved(MediaStreamInterface* remote_stream) {
    EXPECT_TRUE(remote_media_streams_.find(remote_stream->label()) !=
                remote_media_streams_.end());
    EXPECT_EQ(MediaStreamInterface::kEnded, remote_stream->ready_state());
    remote_media_streams_.erase(remote_stream->label());
  }

  virtual void OnStateChange(PeerConnectionSignaling::State state) {
    state_  = state;
  }

  virtual void OnErrorReceived(RoapErrorCode error) {
    last_error_ = error;
  }

  void OnSignalingMessage(const std::string& smessage) {
    last_message_ = smessage;
    if (remote_peer_) {
      remote_peer_->ProcessSignalingMessage(smessage, remote_local_collection_);
    }
  }

  // Tell this object to answer the remote_peer.
  // remote_local_collection is the local collection the remote peer want to
  // send in an answer.
  void AnswerPeer(PeerConnectionSignaling* remote_peer,
                  StreamCollection* remote_local_collection) {
    remote_peer_ = remote_peer;
    remote_local_collection_ = remote_local_collection;
  }

  void CancelAnswerPeer() {
    remote_peer_ = NULL;
    remote_local_collection_.release();
  }

  MediaStreamInterface* RemoteStream(const std::string& label) {
    MediaStreamMap::iterator it = remote_media_streams_.find(label);
    if (it != remote_media_streams_.end())
      return it->second;
    return NULL;
  }

  std::string last_message_;
  int last_error_;
  PeerConnectionSignaling::State state_;

 private:
  MediaStreamMap remote_media_streams_;
  talk_base::scoped_refptr<StreamCollection> remote_local_collection_;
  PeerConnectionSignaling* remote_peer_;
};

// Mock implementation of SessionDescriptionProvider.
// PeerConnectionSignaling uses this object to create session descriptions.
class MockSessionDescriptionProvider : public SessionDescriptionProvider {
 public:
  explicit MockSessionDescriptionProvider(
      cricket::ChannelManager* channel_manager)
      : update_session_description_counter_(0),
        session_description_factory_(
          new cricket::MediaSessionDescriptionFactory(channel_manager)) {
  }
  virtual const cricket::SessionDescription* ProvideOffer(
      const cricket::MediaSessionOptions& options) {
    local_desc_.reset(session_description_factory_->CreateOffer(
        options, local_desc_.get()));
    return local_desc_.get();
  }

  virtual const cricket::SessionDescription* SetRemoteSessionDescription(
      const cricket::SessionDescription* remote_offer,
      const cricket::Candidates& remote_candidates) {
    remote_desc_.reset(remote_offer);
    return remote_desc_.get();
  }

  virtual const cricket::SessionDescription* ProvideAnswer(
      const cricket::MediaSessionOptions& options) {
    local_desc_.reset(session_description_factory_->CreateAnswer(
        remote_desc_.get(), options, local_desc_.get()));
    return local_desc_.get();
  }

  virtual void NegotiationDone() {
    ++update_session_description_counter_;
  }

  size_t update_session_description_counter_;

 protected:
  talk_base::scoped_ptr<cricket::MediaSessionDescriptionFactory>
      session_description_factory_;
  talk_base::scoped_ptr<const cricket::SessionDescription> local_desc_;
  talk_base::scoped_ptr<const cricket::SessionDescription> remote_desc_;
};

// PeerConnectionSignalingTest create two PeerConnectionSignaling instances
// and connects the signals to two MockSignalingObservers.
// This is used in tests to test the signaling between to peers.
class PeerConnectionSignalingTest: public testing::Test {
 protected:
  virtual void SetUp() {
    channel_manager_.reset(new cricket::ChannelManager(
        talk_base::Thread::Current()));
    EXPECT_TRUE(channel_manager_->Init());
    provider1_.reset(new MockSessionDescriptionProvider(
        channel_manager_.get()));
    provider2_.reset(new MockSessionDescriptionProvider(
        channel_manager_.get()));

    signaling1_.reset(new PeerConnectionSignaling(
        talk_base::Thread::Current(), provider1_.get()));
    observer1_.reset(new MockSignalingObserver());
    signaling1_->SignalNewPeerConnectionMessage.connect(
        observer1_.get(), &MockSignalingObserver::OnSignalingMessage);
    signaling1_->SignalRemoteStreamAdded.connect(
        observer1_.get(), &MockSignalingObserver::OnRemoteStreamAdded);
    signaling1_->SignalRemoteStreamRemoved.connect(
        observer1_.get(), &MockSignalingObserver::OnRemoteStreamRemoved);
    signaling1_->SignalErrorMessageReceived.connect(
        observer1_.get(), &MockSignalingObserver::OnErrorReceived);
    signaling1_->SignalStateChange.connect(
        observer1_.get(), &MockSignalingObserver::OnStateChange);

    signaling2_.reset(new PeerConnectionSignaling(
        talk_base::Thread::Current(), provider2_.get()));
    observer2_.reset(new MockSignalingObserver());
    signaling2_->SignalNewPeerConnectionMessage.connect(
        observer2_.get(), &MockSignalingObserver::OnSignalingMessage);
    signaling2_->SignalRemoteStreamAdded.connect(
        observer2_.get(), &MockSignalingObserver::OnRemoteStreamAdded);
    signaling2_->SignalRemoteStreamRemoved.connect(
        observer2_.get(), &MockSignalingObserver::OnRemoteStreamRemoved);
    signaling2_->SignalErrorMessageReceived.connect(
        observer2_.get(), &MockSignalingObserver::OnErrorReceived);
    signaling2_->SignalStateChange.connect(
        observer2_.get(), &MockSignalingObserver::OnStateChange);
  }

  // Create a collection of streams be sent on signaling1__
  talk_base::scoped_refptr<StreamCollection> CreateLocalCollection1() {
    std::string label(kStreamLabel1);
    talk_base::scoped_refptr<LocalMediaStreamInterface> stream1(
        MediaStream::Create(label));

    // Add a local audio track.
    talk_base::scoped_refptr<LocalAudioTrackInterface>
        audio_track(AudioTrack::CreateLocal(kAudioTrackLabel1, NULL));
    stream1->AddTrack(audio_track);

    // Add a local video track.
    talk_base::scoped_refptr<LocalVideoTrackInterface>
        video_track(VideoTrack::CreateLocal(kVideoTrackLabel1, NULL));
    stream1->AddTrack(video_track);

    talk_base::scoped_refptr<StreamCollection> local_collection1(
        StreamCollection::Create());
    local_collection1->AddStream(stream1);

    return local_collection1;
  }

  talk_base::scoped_refptr<StreamCollection> CreateLocalCollection2() {
    std::string label(kStreamLabel2);
    talk_base::scoped_refptr<LocalMediaStreamInterface> stream2(
        MediaStream::Create(label));

    // Add a local audio track.
    talk_base::scoped_refptr<LocalAudioTrackInterface>
        audio_track(AudioTrack::CreateLocal(kAudioTrackLabel2, NULL));
    stream2->AddTrack(audio_track);

    talk_base::scoped_refptr<StreamCollection> local_collection2(
        StreamCollection::Create());
    local_collection2->AddStream(stream2);

    return local_collection2;
  }

  void VerifyStreamStates(StreamCollection* collection,
                          MediaStreamInterface::ReadyState state,
                          MediaStreamTrackInterface::TrackState track_state) {
    for (size_t i = 0; i < collection->count(); ++i) {
      MediaStreamInterface* stream = collection->at(i);
      EXPECT_EQ(state, stream->ready_state());
      for (size_t j = 0; j < stream->audio_tracks()->count(); ++j) {
        AudioTrackInterface* audio = stream->audio_tracks()->at(j);
        EXPECT_EQ(track_state, audio->state());
      }
      for (size_t j = 0; j < stream->video_tracks()->count(); ++j) {
        VideoTrackInterface* video = stream->video_tracks()->at(j);
        EXPECT_EQ(track_state, video->state());
      }
    }
  }

  // Initialize and setup a simple call between signaling1_ and signaling2_.
  // signaling1_ send stream with label kStreamLabel1 to signaling2_.
  void SetUpOneWayCall() {
    // Initialize signaling1_ and signaling_2 by providing the candidates.
    signaling1_->OnCandidatesReady(candidates_);
    signaling2_->OnCandidatesReady(candidates_);

    // Create a local stream collection to be sent on signaling1_.
    talk_base::scoped_refptr<StreamCollection> local_collection1(
        CreateLocalCollection1());

    talk_base::scoped_refptr<StreamCollection> local_collection2(
        StreamCollection::Create());

    // Connect all messages sent from signaling1_ to be received on signaling2_
    observer1_->AnswerPeer(signaling2_.get(), local_collection2);
    // Connect all messages sent from Peer2 to be received on Peer1
    observer2_->AnswerPeer(signaling1_.get(), local_collection1);

    signaling1_->CreateOffer(local_collection1);
    EXPECT_EQ(PeerConnectionSignaling::kWaitingForAnswer,
              signaling1_->GetState());
    EXPECT_EQ(PeerConnectionSignaling::kIdle, signaling2_->GetState());

    // Process posted messages to generate the offer and the answer to the
    // offer.
    talk_base::Thread::Current()->ProcessMessages(1);
    talk_base::Thread::Current()->ProcessMessages(1);

    // Make sure all is setup.
    EXPECT_EQ(PeerConnectionSignaling::kIdle, signaling1_->GetState());
    EXPECT_EQ(PeerConnectionSignaling::kIdle, signaling2_->GetState());

    EXPECT_TRUE(observer2_->RemoteStream(kStreamLabel1) != NULL);
    EXPECT_EQ(0u, signaling1_->remote_streams()->count());
    EXPECT_EQ(1u, signaling2_->remote_streams()->count());
  }

  cricket::Candidates candidates_;
  talk_base::scoped_ptr<MockSignalingObserver> observer1_;
  talk_base::scoped_ptr<MockSignalingObserver> observer2_;
  talk_base::scoped_ptr<MockSessionDescriptionProvider> provider1_;
  talk_base::scoped_ptr<MockSessionDescriptionProvider> provider2_;
  talk_base::scoped_ptr<PeerConnectionSignaling> signaling1_;
  talk_base::scoped_ptr<PeerConnectionSignaling> signaling2_;
  talk_base::scoped_ptr<cricket::ChannelManager> channel_manager_;
};

TEST_F(PeerConnectionSignalingTest, SimpleOneWayCall) {
  // Peer 1 create an offer with only one audio track.
  talk_base::scoped_refptr<StreamCollection> local_collection1(
      CreateLocalCollection1());

  // Verify that the local stream is now initializing.
  VerifyStreamStates(local_collection1.get(),
                     MediaStreamInterface::kInitializing,
                     MediaStreamTrackInterface::kInitializing);

  // Peer 2 only receive. Create an empty collection
  talk_base::scoped_refptr<StreamCollection> local_collection2(
      StreamCollection::Create());

  // Connect all messages sent from Peer1 to be received on Peer2
  observer1_->AnswerPeer(signaling2_.get(), local_collection2);
  // Connect all messages sent from Peer2 to be received on Peer1
  observer2_->AnswerPeer(signaling1_.get(), local_collection1);

  // Peer 1 generates the offer. It is not sent since there is no
  // local candidates ready.
  signaling1_->CreateOffer(local_collection1);

  // Process posted messages.
  talk_base::Thread::Current()->ProcessMessages(1);
  EXPECT_EQ(PeerConnectionSignaling::kInitializing, signaling1_->GetState());

  // Initialize signaling1_ by providing the candidates.
  signaling1_->OnCandidatesReady(candidates_);
  EXPECT_EQ(PeerConnectionSignaling::kWaitingForAnswer,
            signaling1_->GetState());
  // Process posted messages to allow signaling_1 to send the offer.
  talk_base::Thread::Current()->ProcessMessages(1);

  // Verify that signaling_2 is still not initialized.
  // Even though it have received an offer.
  EXPECT_EQ(PeerConnectionSignaling::kInitializing, signaling2_->GetState());

  // Provide the candidates to signaling_2 and let it process the offer.
  signaling2_->OnCandidatesReady(candidates_);
  talk_base::Thread::Current()->ProcessMessages(1);

  // Verify that the offer/answer have been exchanged and the state is good.
  EXPECT_EQ(PeerConnectionSignaling::kIdle, signaling1_->GetState());
  EXPECT_EQ(PeerConnectionSignaling::kIdle, signaling2_->GetState());

  // Verify that the local stream is now sending.
  VerifyStreamStates(local_collection1, MediaStreamInterface::kLive,
                     MediaStreamTrackInterface::kLive);

  // Verify that PeerConnection2 is aware of the sending stream.
  EXPECT_TRUE(observer2_->RemoteStream(kStreamLabel1) != NULL);

  // Verify that both peers have updated the session descriptions.
  EXPECT_EQ(1u, provider1_->update_session_description_counter_);
  EXPECT_EQ(1u, provider2_->update_session_description_counter_);
}

TEST_F(PeerConnectionSignalingTest, Glare) {
  // Setup a call.
  SetUpOneWayCall();

  // Stop sending all messages automatically between Peer 1 and Peer 2.
  observer1_->CancelAnswerPeer();
  observer2_->CancelAnswerPeer();

  // Create an empty collection for Peer 1.
  talk_base::scoped_refptr<StreamCollection> local_collection1(
      StreamCollection::Create());
  // Create a collection for Peer 2.
  talk_base::scoped_refptr<StreamCollection> local_collection2(
      CreateLocalCollection2());

  // Peer 1 create an updated offer.
  signaling1_->CreateOffer(local_collection1);
  // Peer 2 create an updated offer.
  signaling2_->CreateOffer(local_collection2);

  // Process posted messages.
  talk_base::Thread::Current()->ProcessMessages(1);
  talk_base::Thread::Current()->ProcessMessages(1);

  std::string offer_1 = observer1_->last_message_;
  std::string offer_2 = observer2_->last_message_;
  EXPECT_EQ(PeerConnectionSignaling::kWaitingForAnswer,
            signaling1_->GetState());
  EXPECT_EQ(PeerConnectionSignaling::kWaitingForAnswer,
            signaling2_->GetState());

  // Connect all messages sent from Peer 1 to be received on Peer 2
  observer1_->AnswerPeer(signaling2_.get(), local_collection2);
  // Connect all messages sent from Peer 2 to be received on Peer 1
  observer2_->AnswerPeer(signaling1_.get(), local_collection1);

  // Insert the two offers to each Peer to create the Glare.
  signaling1_->ProcessSignalingMessage(offer_2, local_collection1);
  signaling2_->ProcessSignalingMessage(offer_1, local_collection2);

  talk_base::Thread::Current()->ProcessMessages(1);
  talk_base::Thread::Current()->ProcessMessages(1);

  // Make sure all is good.
  EXPECT_EQ(PeerConnectionSignaling::kIdle, signaling1_->GetState());
  EXPECT_EQ(PeerConnectionSignaling::kIdle, signaling2_->GetState());

  // Verify that Peer 1 is receiving kStreamLabel2.
  EXPECT_TRUE(observer1_->RemoteStream(kStreamLabel2) != NULL);
  // Verify that Peer 2 don't receive any streams
  // since it has been removed.
  EXPECT_TRUE(observer2_->RemoteStream(kStreamLabel1) == NULL);

  // Verify that both peers have updated the session descriptions.
  EXPECT_EQ(2u, provider1_->update_session_description_counter_);
  EXPECT_EQ(2u, provider2_->update_session_description_counter_);
}

TEST_F(PeerConnectionSignalingTest, AddRemoveStream) {
  // Initialize signaling1_ and signaling_2 by providing the candidates.
  signaling1_->OnCandidatesReady(candidates_);
  signaling2_->OnCandidatesReady(candidates_);
  // Create a local stream.
  std::string label(kStreamLabel1);
  talk_base::scoped_refptr<LocalMediaStreamInterface> stream(
      MediaStream::Create(label));

  // Add a local audio track.
  talk_base::scoped_refptr<LocalAudioTrackInterface>
      audio_track(AudioTrack::CreateLocal(kAudioTrackLabel1, NULL));
  stream->AddTrack(audio_track);

  // Add a local video track.
  talk_base::scoped_refptr<LocalVideoTrackInterface>
      video_track(VideoTrack::CreateLocal(kVideoTrackLabel1, NULL));
  stream->AddTrack(video_track);

  // Peer 1 create an empty collection
  talk_base::scoped_refptr<StreamCollection> local_collection1(
      StreamCollection::Create());

  // Peer 2 create an empty collection
  talk_base::scoped_refptr<StreamCollection> local_collection2(
      StreamCollection::Create());

  // Connect all messages sent from Peer1 to be received on Peer2
  observer1_->AnswerPeer(signaling2_.get(), local_collection2);
  // Connect all messages sent from Peer2 to be received on Peer1
  observer2_->AnswerPeer(signaling1_.get(), local_collection1);

  // Peer 1 creates an empty offer and send it to Peer2.
  signaling1_->CreateOffer(local_collection1);
  // Process posted messages.
  talk_base::Thread::Current()->ProcessMessages(1);
  talk_base::Thread::Current()->ProcessMessages(1);

  // Verify that both peers have updated the session descriptions.
  EXPECT_EQ(1u, provider1_->update_session_description_counter_);
  EXPECT_EQ(1u, provider2_->update_session_description_counter_);

  // Peer2 add a stream.
  local_collection2->AddStream(stream);

  signaling2_->CreateOffer(local_collection2);
  talk_base::Thread::Current()->ProcessMessages(1);
  talk_base::Thread::Current()->ProcessMessages(1);

  // Verify that the PeerConnection 2 local stream is now sending.
  VerifyStreamStates(local_collection2, MediaStreamInterface::kLive ,
                     MediaStreamTrackInterface::kLive);

  // Verify that PeerConnection1 is aware of the sending stream.
  EXPECT_TRUE(observer1_->RemoteStream(label) != NULL);

  // Verify that both peers have updated the session descriptions.
  EXPECT_EQ(2u, provider1_->update_session_description_counter_);
  EXPECT_EQ(2u, provider2_->update_session_description_counter_);

  // Remove the stream
  local_collection2->RemoveStream(stream);

  signaling2_->CreateOffer(local_collection2);
  talk_base::Thread::Current()->ProcessMessages(1);
  talk_base::Thread::Current()->ProcessMessages(1);

  // Verify that PeerConnection1 is not aware of the sending stream.
  EXPECT_TRUE(observer1_->RemoteStream(label) == NULL);

  // Verify that the PeerConnection 2 local stream is now ended.
  VerifyStreamStates(local_collection2, MediaStreamInterface::kEnded ,
                     MediaStreamTrackInterface::kEnded);

  // Verify that both peers have updated the session descriptions.
  EXPECT_EQ(3u, provider1_->update_session_description_counter_);
  EXPECT_EQ(3u, provider2_->update_session_description_counter_);
}

TEST_F(PeerConnectionSignalingTest, ShutDown) {
  // Setup a call.
  SetUpOneWayCall();

  signaling1_->SendShutDown();

  EXPECT_EQ_WAIT(PeerConnectionSignaling::kShutdownComplete,
                 signaling1_->GetState(), 10);
  EXPECT_EQ_WAIT(PeerConnectionSignaling::kShutdownComplete,
                 signaling2_->GetState(), 10);

  EXPECT_EQ(0u, signaling1_->remote_streams()->count());
  EXPECT_EQ(0u, signaling2_->remote_streams()->count());
  EXPECT_TRUE(observer2_->RemoteStream(kStreamLabel1) == NULL);
  EXPECT_EQ(PeerConnectionSignaling::kShutdownComplete, observer1_->state_);
  EXPECT_EQ(PeerConnectionSignaling::kShutdownComplete, observer2_->state_);

  // Verify that both peers have updated the session descriptions.
  EXPECT_EQ(2u, provider1_->update_session_description_counter_);
  EXPECT_EQ(2u, provider2_->update_session_description_counter_);
}

TEST_F(PeerConnectionSignalingTest, ReceiveError) {
  // Initialize signaling1_
  signaling1_->OnCandidatesReady(candidates_);

  talk_base::scoped_refptr<StreamCollection> local_collection1(
      CreateLocalCollection1());

  signaling1_->CreateOffer(local_collection1);
  talk_base::Thread::Current()->ProcessMessages(1);
  EXPECT_EQ(PeerConnectionSignaling::kWaitingForAnswer,
            signaling1_->GetState());

  RoapSession roap_session;
  roap_session.Parse(observer1_->last_message_);
  signaling1_->ProcessSignalingMessage(roap_session.CreateErrorMessage(
      kNoMatch), local_collection1);
  EXPECT_EQ(kNoMatch, observer1_->last_error_);

  // Check signaling have cleaned up.
  EXPECT_EQ(PeerConnectionSignaling::kIdle, signaling1_->GetState());

  signaling1_->CreateOffer(local_collection1);
  talk_base::Thread::Current()->ProcessMessages(1);
  EXPECT_EQ(PeerConnectionSignaling::kWaitingForAnswer,
            signaling1_->GetState());
}

}  // namespace webrtc