/*
 * 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 <stdio.h>

#include <list>

#include "talk/app/webrtc/mediastream.h"
#include "talk/app/webrtc/peerconnection.h"
#include "talk/app/webrtc/test/fakevideocapturemodule.h"
#include "talk/base/gunit.h"
#include "talk/base/scoped_ptr.h"
#include "talk/base/thread.h"
#include "talk/session/phone/fakevideorenderer.h"
#include "talk/session/phone/videorenderer.h"

void GetAllVideoTracks(webrtc::MediaStreamInterface* media_stream,
                       std::list<webrtc::VideoTrackInterface*>* video_tracks) {
  webrtc::VideoTracks* track_list = media_stream->video_tracks();
  for (size_t i = 0; i < track_list->count(); ++i) {
    webrtc::VideoTrackInterface* track = track_list->at(i);
    video_tracks->push_back(track);
  }
}

class SignalingMessageReceiver {
 public:
  virtual void ReceiveMessage(const std::string& msg) = 0;

  virtual int num_rendered_frames() = 0;

  // Makes it possible for the remote side to decide when to start capturing.
  // This makes it possible to wait with capturing until a renderer has been
  // added.
  virtual void StartCapturing() = 0;

 protected:
  SignalingMessageReceiver() {}
  virtual ~SignalingMessageReceiver() {}
};

class PeerConnectionP2PTestClient
    : public webrtc::PeerConnectionObserver,
      public SignalingMessageReceiver {
 public:
  static PeerConnectionP2PTestClient* CreateClient(int id) {
    PeerConnectionP2PTestClient* client = new PeerConnectionP2PTestClient(id);
    if (!client->Init()) {
      delete client;
      return NULL;
    }
    return client;
  }

  ~PeerConnectionP2PTestClient() {
  }

  void StartSession() {
    if (video_track_.get() != NULL) {
      // Tracks have already been set up.
      return;
    }
    // TODO: the default audio device module is used regardless of
    // the second parameter to the CreateLocalAudioTrack(..) call. Maybe remove
    // the second parameter from the API altogether?
    talk_base::scoped_refptr<webrtc::LocalAudioTrackInterface> audio_track(
        peer_connection_factory_->CreateLocalAudioTrack("audio_track", NULL));

    CreateLocalVideoTrack();

    talk_base::scoped_refptr<webrtc::LocalMediaStreamInterface> stream =
        peer_connection_factory_->CreateLocalMediaStream("stream_label");

    stream->AddTrack(audio_track);
    stream->AddTrack(video_track_);

    peer_connection_->AddStream(stream);
    peer_connection_->CommitStreamChanges();
  }

  void StartCapturing() {
    if (fake_video_capture_module_ != NULL) {
      fake_video_capture_module_->StartCapturing();
    }
  }

  bool SessionActive() {
    return peer_connection_->ready_state() ==
        webrtc::PeerConnectionInterface::kActive;
  }

  void StopSession() {
    if (fake_video_capture_module_ != NULL) {
      fake_video_capture_module_->StopCapturing();
    }
    // TODO: investigate why calling Close() triggers a crash when
    // deleting the PeerConnection.
    // peer_connection_->Close();
  }

  void set_signaling_message_receiver(
      SignalingMessageReceiver* signaling_message_receiver) {
    signaling_message_receiver_ = signaling_message_receiver;
  }

  bool FramesReceivedCheck(int number_of_frames) {
    if (number_of_frames > signaling_message_receiver_->num_rendered_frames()) {
      return false;
    }
    else {
      EXPECT_LT(number_of_frames, fake_video_capture_module_->sent_frames());
    }
    return true;
  }

  // SignalingMessageReceiver callback.
  virtual void ReceiveMessage(const std::string& msg) {
    peer_connection_->ProcessSignalingMessage(msg);
  }

  virtual int num_rendered_frames() {
    if (fake_video_renderer_ == NULL) {
      return -1;
    }
    return fake_video_renderer_->num_rendered_frames();
  }

  // PeerConnectionObserver callbacks.
  virtual void OnError() {}
  virtual void OnMessage(const std::string&) {}
  virtual void OnSignalingMessage(const std::string& msg)  {
    if (signaling_message_receiver_ == NULL) {
      // Remote party may be deleted.
      return;
    }
    signaling_message_receiver_->ReceiveMessage(msg);
  }
  virtual void OnStateChange(StateType /*state_changed*/) {}
  virtual void OnAddStream(webrtc::MediaStreamInterface* media_stream) {
    std::list<webrtc::VideoTrackInterface*> video_tracks;
    GetAllVideoTracks(media_stream, &video_tracks);
    int track_id = 0;
    // Currently only one video track is supported.
    // TODO: enable multiple video tracks.
    EXPECT_EQ(1u, video_tracks.size());
    for (std::list<webrtc::VideoTrackInterface*>::iterator iter =
             video_tracks.begin();
         iter != video_tracks.end();
         ++iter) {
      fake_video_renderer_ = new cricket::FakeVideoRenderer();
      video_renderer_wrapper_ = webrtc::CreateVideoRenderer(
          fake_video_renderer_);
      (*iter)->SetRenderer(video_renderer_wrapper_);
      track_id++;
    }
    // The video renderer has been added. Tell the far end to start capturing
    // frames. That way the number of captured frames should be equal to number
    // of rendered frames.
    if (signaling_message_receiver_ != NULL) {
      signaling_message_receiver_->StartCapturing();
      return;
    }
  }
  virtual void OnRemoveStream(webrtc::MediaStreamInterface* /*media_stream*/) {
  }

 private:
  explicit PeerConnectionP2PTestClient(int id)
      : id_(id),
        fake_video_capture_module_(NULL),
        fake_video_renderer_(NULL),
        signaling_message_receiver_(NULL) {
  }

  bool Init() {
    EXPECT_TRUE(peer_connection_.get() == NULL);
    EXPECT_TRUE(peer_connection_factory_.get() == NULL);
    peer_connection_factory_ = webrtc::CreatePeerConnectionFactory();
    if (peer_connection_factory_.get() == NULL) {
      return false;
    }

    const std::string server_configuration = "STUN stun.l.google.com:19302";
    peer_connection_ = peer_connection_factory_->CreatePeerConnection(
        server_configuration, this);
    return peer_connection_.get() != NULL;
  }

  void GenerateRecordingFileName(int track, std::string* file_name) {
    if (file_name == NULL) {
      return;
    }
    std::stringstream file_name_stream;
    file_name_stream << "p2p_test_client_" << id_ << "_videotrack_" << track <<
        ".yuv";
    file_name->clear();
    *file_name = file_name_stream.str();
  }

  void CreateLocalVideoTrack() {
    fake_video_capture_module_ = FakeVideoCaptureModule::Create(
        talk_base::Thread::Current());
    video_track_ = peer_connection_factory_->CreateLocalVideoTrack(
        "video_track", fake_video_capture_module_);
  }

  int id_;
  talk_base::scoped_refptr<webrtc::PeerConnectionInterface> peer_connection_;
  talk_base::scoped_refptr<webrtc::PeerConnectionFactoryInterface>
      peer_connection_factory_;

  // Owns and ensures that fake_video_capture_module_ is available as long as
  // this class exists.  It also ensures destruction of the memory associated
  // with it when this class is deleted.
  talk_base::scoped_refptr<webrtc::LocalVideoTrackInterface> video_track_;
  // Needed to keep track of number of frames send.
  FakeVideoCaptureModule* fake_video_capture_module_;
  // Ensures that fake_video_renderer_ is available as long as this class
  // exists. It also ensures destruction of the memory associated with it when
  // this class is deleted.
  talk_base::scoped_refptr<webrtc::VideoRendererWrapperInterface>
      video_renderer_wrapper_;
  // Needed to keep track of number of frames received.
  cricket::FakeVideoRenderer* fake_video_renderer_;

  // For remote peer communication.
  SignalingMessageReceiver* signaling_message_receiver_;
};

class P2PTestConductor : public testing::Test {
 public:
  virtual void SetUp() {
    EXPECT_TRUE(Init());
  }
  // Return true if session no longer is pending. I.e. if the session is active
  // or failed.
  bool ActivationNotPending() {
    if (!IsInitialized()) {
      return true;
    }
    return SessionActive();
  }
  bool SessionActive() {
    return initiating_client_->SessionActive() &&
        receiving_client_->SessionActive();
  }
  // Return true if the number of frames provided have been received or it is
  // known that that will never occur (e.g. no frames will be sent or
  // captured).
  bool FramesNotPending(int frames_to_receive) {
    if (!IsInitialized()) {
      return true;
    }
    return FramesReceivedCheck(frames_to_receive);
  }
  bool FramesReceivedCheck(int frames_received) {
    return initiating_client_->FramesReceivedCheck(frames_received) &&
        receiving_client_->FramesReceivedCheck(frames_received);
  }
  ~P2PTestConductor() {
    if (initiating_client_.get() != NULL) {
      initiating_client_->set_signaling_message_receiver(NULL);
    }
    if (receiving_client_.get() != NULL) {
      receiving_client_->set_signaling_message_receiver(NULL);
    }
  }

  bool StartSession() {
    if (!IsInitialized()) {
      return false;
    }
    initiating_client_->StartSession();
    receiving_client_->StartSession();
    return true;
  }

  bool StopSession() {
    if (!IsInitialized()) {
      return false;
    }
    initiating_client_->StopSession();
    receiving_client_->StopSession();
    return true;
  }

 private:
  bool Init() {
    initiating_client_.reset(PeerConnectionP2PTestClient::CreateClient(0));
    receiving_client_.reset(PeerConnectionP2PTestClient::CreateClient(1));
    if ((initiating_client_.get() == NULL) ||
        (receiving_client_.get() == NULL)) {
      return false;
    }
    initiating_client_->set_signaling_message_receiver(receiving_client_.get());
    receiving_client_->set_signaling_message_receiver(initiating_client_.get());
    return true;
  }
  bool IsInitialized() const {
    return (initiating_client_.get() != NULL) &&
        (receiving_client_.get() != NULL);
  }

  talk_base::scoped_ptr<PeerConnectionP2PTestClient> initiating_client_;
  talk_base::scoped_ptr<PeerConnectionP2PTestClient> receiving_client_;
};

// This test sets up a call between two parties. Both parties send static frames
// to each other. Once the test is finished the number of sent frames is
// compared to the number of recieved frames.
TEST_F(P2PTestConductor, LocalP2PTest) {
  EXPECT_TRUE(StartSession());
  const int kMaxWaitForActivationMs = 5000;
  EXPECT_TRUE_WAIT(ActivationNotPending(), kMaxWaitForActivationMs);
  EXPECT_TRUE(SessionActive());

  const int kEndFrameCount = 10;
  const int kMaxWaitForFramesMs = 5000;
  EXPECT_TRUE_WAIT(FramesNotPending(kEndFrameCount), kMaxWaitForFramesMs);
  EXPECT_TRUE(FramesReceivedCheck(kEndFrameCount));
  EXPECT_TRUE(StopSession());
}