pc/test/mock_peer_connection_observers.h - src - Git at Google

 /*
  *  Copyright 2012 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.
  */

 // This file contains mock implementations of observers used in PeerConnection.
 // TODO(steveanton): These aren't really mocks and should be renamed.

 #ifndef PC_TEST_MOCK_PEER_CONNECTION_OBSERVERS_H_
 #define PC_TEST_MOCK_PEER_CONNECTION_OBSERVERS_H_

 #include <map>
 #include <memory>
 #include <string>
 #include <utility>
 #include <vector>

 #include "api/data_channel_interface.h"
 #include "api/jsep_ice_candidate.h"
 #include "pc/stream_collection.h"
 #include "rtc_base/checks.h"

 namespace webrtc {

 class MockPeerConnectionObserver : public PeerConnectionObserver {
  public:
   struct AddTrackEvent {
     explicit AddTrackEvent(
         rtc::scoped_refptr<RtpReceiverInterface> event_receiver,
         std::vector<rtc::scoped_refptr<MediaStreamInterface>> event_streams)
         : receiver(std::move(event_receiver)),
           streams(std::move(event_streams)) {
       for (auto stream : streams) {
         std::vector<rtc::scoped_refptr<MediaStreamTrackInterface>> tracks;
         for (auto audio_track : stream->GetAudioTracks()) {
           tracks.push_back(audio_track);
         }
         for (auto video_track : stream->GetVideoTracks()) {
           tracks.push_back(video_track);
         }
         snapshotted_stream_tracks[stream] = tracks;
       }
     }

     rtc::scoped_refptr<RtpReceiverInterface> receiver;
     std::vector<rtc::scoped_refptr<MediaStreamInterface>> streams;
     // This map records the tracks present in each stream at the time the
     // OnAddTrack callback was issued.
     std::map<rtc::scoped_refptr<MediaStreamInterface>,
              std::vector<rtc::scoped_refptr<MediaStreamTrackInterface>>>
         snapshotted_stream_tracks;
   };

   MockPeerConnectionObserver() : remote_streams_(StreamCollection::Create()) {}
   virtual ~MockPeerConnectionObserver() {}
   void SetPeerConnectionInterface(PeerConnectionInterface* pc) {
     pc_ = pc;
     if (pc) {
       state_ = pc_->signaling_state();
     }
   }
   void OnSignalingChange(
       PeerConnectionInterface::SignalingState new_state) override {
     RTC_DCHECK(pc_);
     RTC_DCHECK(pc_->signaling_state() == new_state);
     state_ = new_state;
   }

   MediaStreamInterface* RemoteStream(const std::string& label) {
     return remote_streams_->find(label);
   }
   StreamCollectionInterface* remote_streams() const { return remote_streams_; }
   void OnAddStream(rtc::scoped_refptr<MediaStreamInterface> stream) override {
     last_added_stream_ = stream;
     remote_streams_->AddStream(stream);
   }
   void OnRemoveStream(
       rtc::scoped_refptr<MediaStreamInterface> stream) override {
     last_removed_stream_ = stream;
     remote_streams_->RemoveStream(stream);
   }
   void OnRenegotiationNeeded() override { renegotiation_needed_ = true; }
   void OnDataChannel(
       rtc::scoped_refptr<DataChannelInterface> data_channel) override {
     last_datachannel_ = data_channel;
   }

   void OnIceConnectionChange(
       PeerConnectionInterface::IceConnectionState new_state) override {
     RTC_DCHECK(pc_);
     RTC_DCHECK(pc_->ice_connection_state() == new_state);
     // When ICE is finished, the caller will get to a kIceConnectionCompleted
     // state, because it has the ICE controlling role, while the callee
     // will get to a kIceConnectionConnected state. This means that both ICE
     // and DTLS are connected.
     ice_connected_ =
         (new_state == PeerConnectionInterface::kIceConnectionConnected) ||
         (new_state == PeerConnectionInterface::kIceConnectionCompleted);
     callback_triggered_ = true;
   }
   void OnIceGatheringChange(
       PeerConnectionInterface::IceGatheringState new_state) override {
     RTC_DCHECK(pc_);
     RTC_DCHECK(pc_->ice_gathering_state() == new_state);
     ice_gathering_complete_ =
         new_state == PeerConnectionInterface::kIceGatheringComplete;
     callback_triggered_ = true;
   }
   void OnIceCandidate(const IceCandidateInterface* candidate) override {
     RTC_DCHECK(pc_);
     RTC_DCHECK(PeerConnectionInterface::kIceGatheringNew !=
                pc_->ice_gathering_state());
     candidates_.push_back(std::make_unique<JsepIceCandidate>(
         candidate->sdp_mid(), candidate->sdp_mline_index(),
         candidate->candidate()));
     callback_triggered_ = true;
   }

   void OnIceCandidatesRemoved(
       const std::vector<cricket::Candidate>& candidates) override {
     num_candidates_removed_++;
     callback_triggered_ = true;
   }

   void OnIceConnectionReceivingChange(bool receiving) override {
     callback_triggered_ = true;
   }

   void OnAddTrack(rtc::scoped_refptr<RtpReceiverInterface> receiver,
                   const std::vector<rtc::scoped_refptr<MediaStreamInterface>>&
                       streams) override {
     RTC_DCHECK(receiver);
     num_added_tracks_++;
     last_added_track_label_ = receiver->id();
     add_track_events_.push_back(AddTrackEvent(receiver, streams));
   }

   void OnTrack(
       rtc::scoped_refptr<RtpTransceiverInterface> transceiver) override {
     on_track_transceivers_.push_back(transceiver);
   }

   void OnRemoveTrack(
       rtc::scoped_refptr<RtpReceiverInterface> receiver) override {
     remove_track_events_.push_back(receiver);
   }

   std::vector<rtc::scoped_refptr<RtpReceiverInterface>> GetAddTrackReceivers() {
     std::vector<rtc::scoped_refptr<RtpReceiverInterface>> receivers;
     for (const AddTrackEvent& event : add_track_events_) {
       receivers.push_back(event.receiver);
     }
     return receivers;
   }

   int CountAddTrackEventsForStream(const std::string& stream_id) {
     int found_tracks = 0;
     for (const AddTrackEvent& event : add_track_events_) {
       bool has_stream_id = false;
       for (auto stream : event.streams) {
         if (stream->id() == stream_id) {
           has_stream_id = true;
           break;
         }
       }
       if (has_stream_id) {
         ++found_tracks;
       }
     }
     return found_tracks;
   }

   // Returns the id of the last added stream.
   // Empty string if no stream have been added.
   std::string GetLastAddedStreamId() {
     if (last_added_stream_.get())
       return last_added_stream_->id();
     return "";
   }
   std::string GetLastRemovedStreamId() {
     if (last_removed_stream_.get())
       return last_removed_stream_->id();
     return "";
   }

   IceCandidateInterface* last_candidate() {
     if (candidates_.empty()) {
       return nullptr;
     } else {
       return candidates_.back().get();
     }
   }

   std::vector<const IceCandidateInterface*> GetAllCandidates() {
     std::vector<const IceCandidateInterface*> candidates;
     for (const auto& candidate : candidates_) {
       candidates.push_back(candidate.get());
     }
     return candidates;
   }

   std::vector<IceCandidateInterface*> GetCandidatesByMline(int mline_index) {
     std::vector<IceCandidateInterface*> candidates;
     for (const auto& candidate : candidates_) {
       if (candidate->sdp_mline_index() == mline_index) {
         candidates.push_back(candidate.get());
       }
     }
     return candidates;
   }

   bool negotiation_needed() const { return renegotiation_needed_; }
   void clear_negotiation_needed() { renegotiation_needed_ = false; }

   rtc::scoped_refptr<PeerConnectionInterface> pc_;
   PeerConnectionInterface::SignalingState state_;
   std::vector<std::unique_ptr<IceCandidateInterface>> candidates_;
   rtc::scoped_refptr<DataChannelInterface> last_datachannel_;
   rtc::scoped_refptr<StreamCollection> remote_streams_;
   bool renegotiation_needed_ = false;
   bool ice_gathering_complete_ = false;
   bool ice_connected_ = false;
   bool callback_triggered_ = false;
   int num_added_tracks_ = 0;
   std::string last_added_track_label_;
   std::vector<AddTrackEvent> add_track_events_;
   std::vector<rtc::scoped_refptr<RtpReceiverInterface>> remove_track_events_;
   std::vector<rtc::scoped_refptr<RtpTransceiverInterface>>
       on_track_transceivers_;
   int num_candidates_removed_ = 0;

  private:
   rtc::scoped_refptr<MediaStreamInterface> last_added_stream_;
   rtc::scoped_refptr<MediaStreamInterface> last_removed_stream_;
 };

 class MockCreateSessionDescriptionObserver
     : public webrtc::CreateSessionDescriptionObserver {
  public:
   MockCreateSessionDescriptionObserver()
       : called_(false),
         error_("MockCreateSessionDescriptionObserver not called") {}
   virtual ~MockCreateSessionDescriptionObserver() {}
   void OnSuccess(SessionDescriptionInterface* desc) override {
     called_ = true;
     error_ = "";
     desc_.reset(desc);
   }
   void OnFailure(webrtc::RTCError error) override {
     called_ = true;
     error_ = error.message();
   }
   bool called() const { return called_; }
   bool result() const { return error_.empty(); }
   const std::string& error() const { return error_; }
   std::unique_ptr<SessionDescriptionInterface> MoveDescription() {
     return std::move(desc_);
   }

  private:
   bool called_;
   std::string error_;
   std::unique_ptr<SessionDescriptionInterface> desc_;
 };

 class MockSetSessionDescriptionObserver
     : public webrtc::SetSessionDescriptionObserver {
  public:
   static rtc::scoped_refptr<MockSetSessionDescriptionObserver> Create() {
     return new rtc::RefCountedObject<MockSetSessionDescriptionObserver>();
   }

   MockSetSessionDescriptionObserver()
       : called_(false),
         error_("MockSetSessionDescriptionObserver not called") {}
   ~MockSetSessionDescriptionObserver() override {}
   void OnSuccess() override {
     called_ = true;
     error_ = "";
   }
   void OnFailure(webrtc::RTCError error) override {
     called_ = true;
     error_ = error.message();
   }

   bool called() const { return called_; }
   bool result() const { return error_.empty(); }
   const std::string& error() const { return error_; }

  private:
   bool called_;
   std::string error_;
 };

 class FakeSetLocalDescriptionObserver
     : public rtc::RefCountedObject<SetLocalDescriptionObserverInterface> {
  public:
   bool called() const { return error_.has_value(); }
   RTCError& error() {
     RTC_DCHECK(error_.has_value());
     return *error_;
   }

   // SetLocalDescriptionObserverInterface implementation.
   void OnSetLocalDescriptionComplete(RTCError error) override {
     error_ = std::move(error);
   }

  private:
   // Set on complete, on success this is set to an RTCError::OK() error.
   absl::optional<RTCError> error_;
 };

 class FakeSetRemoteDescriptionObserver
     : public rtc::RefCountedObject<SetRemoteDescriptionObserverInterface> {
  public:
   bool called() const { return error_.has_value(); }
   RTCError& error() {
     RTC_DCHECK(error_.has_value());
     return *error_;
   }

   // SetRemoteDescriptionObserverInterface implementation.
   void OnSetRemoteDescriptionComplete(RTCError error) override {
     error_ = std::move(error);
   }

  private:
   // Set on complete, on success this is set to an RTCError::OK() error.
   absl::optional<RTCError> error_;
 };

 class MockDataChannelObserver : public webrtc::DataChannelObserver {
  public:
   explicit MockDataChannelObserver(webrtc::DataChannelInterface* channel)
       : channel_(channel) {
     channel_->RegisterObserver(this);
     state_ = channel_->state();
   }
   virtual ~MockDataChannelObserver() { channel_->UnregisterObserver(); }

   void OnBufferedAmountChange(uint64_t previous_amount) override {}

   void OnStateChange() override { state_ = channel_->state(); }
   void OnMessage(const DataBuffer& buffer) override {
     messages_.push_back(
         std::string(buffer.data.data<char>(), buffer.data.size()));
   }

   bool IsOpen() const { return state_ == DataChannelInterface::kOpen; }
   std::vector<std::string> messages() const { return messages_; }
   std::string last_message() const {
     return messages_.empty() ? std::string() : messages_.back();
   }
   size_t received_message_count() const { return messages_.size(); }

  private:
   rtc::scoped_refptr<webrtc::DataChannelInterface> channel_;
   DataChannelInterface::DataState state_;
   std::vector<std::string> messages_;
 };

 class MockStatsObserver : public webrtc::StatsObserver {
  public:
   MockStatsObserver() : called_(false), stats_() {}
   virtual ~MockStatsObserver() {}

   virtual void OnComplete(const StatsReports& reports) {
     RTC_CHECK(!called_);
     called_ = true;
     stats_.Clear();
     stats_.number_of_reports = reports.size();
     for (const auto* r : reports) {
       if (r->type() == StatsReport::kStatsReportTypeSsrc) {
         stats_.timestamp = r->timestamp();
         GetIntValue(r, StatsReport::kStatsValueNameAudioOutputLevel,
                     &stats_.audio_output_level);
         GetIntValue(r, StatsReport::kStatsValueNameAudioInputLevel,
                     &stats_.audio_input_level);
         GetIntValue(r, StatsReport::kStatsValueNameBytesReceived,
                     &stats_.bytes_received);
         GetIntValue(r, StatsReport::kStatsValueNameBytesSent,
                     &stats_.bytes_sent);
         GetInt64Value(r, StatsReport::kStatsValueNameCaptureStartNtpTimeMs,
                       &stats_.capture_start_ntp_time);
         stats_.track_ids.emplace_back();
         GetStringValue(r, StatsReport::kStatsValueNameTrackId,
                        &stats_.track_ids.back());
       } else if (r->type() == StatsReport::kStatsReportTypeBwe) {
         stats_.timestamp = r->timestamp();
         GetIntValue(r, StatsReport::kStatsValueNameAvailableReceiveBandwidth,
                     &stats_.available_receive_bandwidth);
       } else if (r->type() == StatsReport::kStatsReportTypeComponent) {
         stats_.timestamp = r->timestamp();
         GetStringValue(r, StatsReport::kStatsValueNameDtlsCipher,
                        &stats_.dtls_cipher);
         GetStringValue(r, StatsReport::kStatsValueNameSrtpCipher,
                        &stats_.srtp_cipher);
       }
     }
   }

   bool called() const { return called_; }
   size_t number_of_reports() const { return stats_.number_of_reports; }
   double timestamp() const { return stats_.timestamp; }

   int AudioOutputLevel() const {
     RTC_CHECK(called_);
     return stats_.audio_output_level;
   }

   int AudioInputLevel() const {
     RTC_CHECK(called_);
     return stats_.audio_input_level;
   }

   int BytesReceived() const {
     RTC_CHECK(called_);
     return stats_.bytes_received;
   }

   int BytesSent() const {
     RTC_CHECK(called_);
     return stats_.bytes_sent;
   }

   int64_t CaptureStartNtpTime() const {
     RTC_CHECK(called_);
     return stats_.capture_start_ntp_time;
   }

   int AvailableReceiveBandwidth() const {
     RTC_CHECK(called_);
     return stats_.available_receive_bandwidth;
   }

   std::string DtlsCipher() const {
     RTC_CHECK(called_);
     return stats_.dtls_cipher;
   }

   std::string SrtpCipher() const {
     RTC_CHECK(called_);
     return stats_.srtp_cipher;
   }

   std::vector<std::string> TrackIds() const {
     RTC_CHECK(called_);
     return stats_.track_ids;
   }

  private:
   bool GetIntValue(const StatsReport* report,
                    StatsReport::StatsValueName name,
                    int* value) {
     const StatsReport::Value* v = report->FindValue(name);
     if (v) {
       // TODO(tommi): We should really just be using an int here :-/
       *value = rtc::FromString<int>(v->ToString());
     }
     return v != nullptr;
   }

   bool GetInt64Value(const StatsReport* report,
                      StatsReport::StatsValueName name,
                      int64_t* value) {
     const StatsReport::Value* v = report->FindValue(name);
     if (v) {
       // TODO(tommi): We should really just be using an int here :-/
       *value = rtc::FromString<int64_t>(v->ToString());
     }
     return v != nullptr;
   }

   bool GetStringValue(const StatsReport* report,
                       StatsReport::StatsValueName name,
                       std::string* value) {
     const StatsReport::Value* v = report->FindValue(name);
     if (v)
       *value = v->ToString();
     return v != nullptr;
   }

   bool called_;
   struct {
     void Clear() {
       number_of_reports = 0;
       timestamp = 0;
       audio_output_level = 0;
       audio_input_level = 0;
       bytes_received = 0;
       bytes_sent = 0;
       capture_start_ntp_time = 0;
       available_receive_bandwidth = 0;
       dtls_cipher.clear();
       srtp_cipher.clear();
       track_ids.clear();
     }

     size_t number_of_reports;
     double timestamp;
     int audio_output_level;
     int audio_input_level;
     int bytes_received;
     int bytes_sent;
     int64_t capture_start_ntp_time;
     int available_receive_bandwidth;
     std::string dtls_cipher;
     std::string srtp_cipher;
     std::vector<std::string> track_ids;
   } stats_;
 };

 // Helper class that just stores the report from the callback.
 class MockRTCStatsCollectorCallback : public webrtc::RTCStatsCollectorCallback {
  public:
   rtc::scoped_refptr<const RTCStatsReport> report() { return report_; }

   bool called() const { return called_; }

  protected:
   void OnStatsDelivered(
       const rtc::scoped_refptr<const RTCStatsReport>& report) override {
     report_ = report;
     called_ = true;
   }

  private:
   bool called_ = false;
   rtc::scoped_refptr<const RTCStatsReport> report_;
 };

 }  // namespace webrtc

 #endif  // PC_TEST_MOCK_PEER_CONNECTION_OBSERVERS_H_
	/*
	* Copyright 2012 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.
	*/

	// This file contains mock implementations of observers used in PeerConnection.
	// TODO(steveanton): These aren't really mocks and should be renamed.

	#ifndef PC_TEST_MOCK_PEER_CONNECTION_OBSERVERS_H_
	#define PC_TEST_MOCK_PEER_CONNECTION_OBSERVERS_H_

	#include <map>
	#include <memory>
	#include <string>
	#include <utility>
	#include <vector>

	#include "api/data_channel_interface.h"
	#include "api/jsep_ice_candidate.h"
	#include "pc/stream_collection.h"
	#include "rtc_base/checks.h"

	namespace webrtc {

	class MockPeerConnectionObserver : public PeerConnectionObserver {
	public:
	struct AddTrackEvent {
	explicit AddTrackEvent(
	rtc::scoped_refptr<RtpReceiverInterface> event_receiver,
	std::vector<rtc::scoped_refptr<MediaStreamInterface>> event_streams)
	: receiver(std::move(event_receiver)),
	streams(std::move(event_streams)) {
	for (auto stream : streams) {
	std::vector<rtc::scoped_refptr<MediaStreamTrackInterface>> tracks;
	for (auto audio_track : stream->GetAudioTracks()) {
	tracks.push_back(audio_track);
	}
	for (auto video_track : stream->GetVideoTracks()) {
	tracks.push_back(video_track);
	}
	snapshotted_stream_tracks[stream] = tracks;
	}
	}

	rtc::scoped_refptr<RtpReceiverInterface> receiver;
	std::vector<rtc::scoped_refptr<MediaStreamInterface>> streams;
	// This map records the tracks present in each stream at the time the
	// OnAddTrack callback was issued.
	std::map<rtc::scoped_refptr<MediaStreamInterface>,
	std::vector<rtc::scoped_refptr<MediaStreamTrackInterface>>>
	snapshotted_stream_tracks;
	};

	MockPeerConnectionObserver() : remote_streams_(StreamCollection::Create()) {}
	virtual ~MockPeerConnectionObserver() {}
	void SetPeerConnectionInterface(PeerConnectionInterface* pc) {
	pc_ = pc;
	if (pc) {
	state_ = pc_->signaling_state();
	}
	}
	void OnSignalingChange(
	PeerConnectionInterface::SignalingState new_state) override {
	RTC_DCHECK(pc_);
	RTC_DCHECK(pc_->signaling_state() == new_state);
	state_ = new_state;
	}

	MediaStreamInterface* RemoteStream(const std::string& label) {
	return remote_streams_->find(label);
	}
	StreamCollectionInterface* remote_streams() const { return remote_streams_; }
	void OnAddStream(rtc::scoped_refptr<MediaStreamInterface> stream) override {
	last_added_stream_ = stream;
	remote_streams_->AddStream(stream);
	}
	void OnRemoveStream(
	rtc::scoped_refptr<MediaStreamInterface> stream) override {
	last_removed_stream_ = stream;
	remote_streams_->RemoveStream(stream);
	}
	void OnRenegotiationNeeded() override { renegotiation_needed_ = true; }
	void OnDataChannel(
	rtc::scoped_refptr<DataChannelInterface> data_channel) override {
	last_datachannel_ = data_channel;
	}

	void OnIceConnectionChange(
	PeerConnectionInterface::IceConnectionState new_state) override {
	RTC_DCHECK(pc_);
	RTC_DCHECK(pc_->ice_connection_state() == new_state);
	// When ICE is finished, the caller will get to a kIceConnectionCompleted
	// state, because it has the ICE controlling role, while the callee
	// will get to a kIceConnectionConnected state. This means that both ICE
	// and DTLS are connected.
	ice_connected_ =
	(new_state == PeerConnectionInterface::kIceConnectionConnected) \|\|
	(new_state == PeerConnectionInterface::kIceConnectionCompleted);
	callback_triggered_ = true;
	}
	void OnIceGatheringChange(
	PeerConnectionInterface::IceGatheringState new_state) override {
	RTC_DCHECK(pc_);
	RTC_DCHECK(pc_->ice_gathering_state() == new_state);
	ice_gathering_complete_ =
	new_state == PeerConnectionInterface::kIceGatheringComplete;
	callback_triggered_ = true;
	}
	void OnIceCandidate(const IceCandidateInterface* candidate) override {
	RTC_DCHECK(pc_);
	RTC_DCHECK(PeerConnectionInterface::kIceGatheringNew !=
	pc_->ice_gathering_state());
	candidates_.push_back(std::make_unique<JsepIceCandidate>(
	candidate->sdp_mid(), candidate->sdp_mline_index(),
	candidate->candidate()));
	callback_triggered_ = true;
	}

	void OnIceCandidatesRemoved(
	const std::vector<cricket::Candidate>& candidates) override {
	num_candidates_removed_++;
	callback_triggered_ = true;
	}

	void OnIceConnectionReceivingChange(bool receiving) override {
	callback_triggered_ = true;
	}

	void OnAddTrack(rtc::scoped_refptr<RtpReceiverInterface> receiver,
	const std::vector<rtc::scoped_refptr<MediaStreamInterface>>&
	streams) override {
	RTC_DCHECK(receiver);
	num_added_tracks_++;
	last_added_track_label_ = receiver->id();
	add_track_events_.push_back(AddTrackEvent(receiver, streams));
	}

	void OnTrack(
	rtc::scoped_refptr<RtpTransceiverInterface> transceiver) override {
	on_track_transceivers_.push_back(transceiver);
	}

	void OnRemoveTrack(
	rtc::scoped_refptr<RtpReceiverInterface> receiver) override {
	remove_track_events_.push_back(receiver);
	}

	std::vector<rtc::scoped_refptr<RtpReceiverInterface>> GetAddTrackReceivers() {
	std::vector<rtc::scoped_refptr<RtpReceiverInterface>> receivers;
	for (const AddTrackEvent& event : add_track_events_) {
	receivers.push_back(event.receiver);
	}
	return receivers;
	}

	int CountAddTrackEventsForStream(const std::string& stream_id) {
	int found_tracks = 0;
	for (const AddTrackEvent& event : add_track_events_) {
	bool has_stream_id = false;
	for (auto stream : event.streams) {
	if (stream->id() == stream_id) {
	has_stream_id = true;
	break;
	}
	}
	if (has_stream_id) {
	++found_tracks;
	}
	}
	return found_tracks;
	}

	// Returns the id of the last added stream.
	// Empty string if no stream have been added.
	std::string GetLastAddedStreamId() {
	if (last_added_stream_.get())
	return last_added_stream_->id();
	return "";
	}
	std::string GetLastRemovedStreamId() {
	if (last_removed_stream_.get())
	return last_removed_stream_->id();
	return "";
	}

	IceCandidateInterface* last_candidate() {
	if (candidates_.empty()) {
	return nullptr;
	} else {
	return candidates_.back().get();
	}
	}

	std::vector<const IceCandidateInterface*> GetAllCandidates() {
	std::vector<const IceCandidateInterface*> candidates;
	for (const auto& candidate : candidates_) {
	candidates.push_back(candidate.get());
	}
	return candidates;
	}

	std::vector<IceCandidateInterface*> GetCandidatesByMline(int mline_index) {
	std::vector<IceCandidateInterface*> candidates;
	for (const auto& candidate : candidates_) {
	if (candidate->sdp_mline_index() == mline_index) {
	candidates.push_back(candidate.get());
	}
	}
	return candidates;
	}

	bool negotiation_needed() const { return renegotiation_needed_; }
	void clear_negotiation_needed() { renegotiation_needed_ = false; }

	rtc::scoped_refptr<PeerConnectionInterface> pc_;
	PeerConnectionInterface::SignalingState state_;
	std::vector<std::unique_ptr<IceCandidateInterface>> candidates_;
	rtc::scoped_refptr<DataChannelInterface> last_datachannel_;
	rtc::scoped_refptr<StreamCollection> remote_streams_;
	bool renegotiation_needed_ = false;
	bool ice_gathering_complete_ = false;
	bool ice_connected_ = false;
	bool callback_triggered_ = false;
	int num_added_tracks_ = 0;
	std::string last_added_track_label_;
	std::vector<AddTrackEvent> add_track_events_;
	std::vector<rtc::scoped_refptr<RtpReceiverInterface>> remove_track_events_;
	std::vector<rtc::scoped_refptr<RtpTransceiverInterface>>
	on_track_transceivers_;
	int num_candidates_removed_ = 0;

	private:
	rtc::scoped_refptr<MediaStreamInterface> last_added_stream_;
	rtc::scoped_refptr<MediaStreamInterface> last_removed_stream_;
	};

	class MockCreateSessionDescriptionObserver
	: public webrtc::CreateSessionDescriptionObserver {
	public:
	MockCreateSessionDescriptionObserver()
	: called_(false),
	error_("MockCreateSessionDescriptionObserver not called") {}
	virtual ~MockCreateSessionDescriptionObserver() {}
	void OnSuccess(SessionDescriptionInterface* desc) override {
	called_ = true;
	error_ = "";
	desc_.reset(desc);
	}
	void OnFailure(webrtc::RTCError error) override {
	called_ = true;
	error_ = error.message();
	}
	bool called() const { return called_; }
	bool result() const { return error_.empty(); }
	const std::string& error() const { return error_; }
	std::unique_ptr<SessionDescriptionInterface> MoveDescription() {
	return std::move(desc_);
	}

	private:
	bool called_;
	std::string error_;
	std::unique_ptr<SessionDescriptionInterface> desc_;
	};

	class MockSetSessionDescriptionObserver
	: public webrtc::SetSessionDescriptionObserver {
	public:
	static rtc::scoped_refptr<MockSetSessionDescriptionObserver> Create() {
	return new rtc::RefCountedObject<MockSetSessionDescriptionObserver>();
	}

	MockSetSessionDescriptionObserver()
	: called_(false),
	error_("MockSetSessionDescriptionObserver not called") {}
	~MockSetSessionDescriptionObserver() override {}
	void OnSuccess() override {
	called_ = true;
	error_ = "";
	}
	void OnFailure(webrtc::RTCError error) override {
	called_ = true;
	error_ = error.message();
	}

	bool called() const { return called_; }
	bool result() const { return error_.empty(); }
	const std::string& error() const { return error_; }

	private:
	bool called_;
	std::string error_;
	};

	class FakeSetLocalDescriptionObserver
	: public rtc::RefCountedObject<SetLocalDescriptionObserverInterface> {
	public:
	bool called() const { return error_.has_value(); }
	RTCError& error() {
	RTC_DCHECK(error_.has_value());
	return *error_;
	}

	// SetLocalDescriptionObserverInterface implementation.
	void OnSetLocalDescriptionComplete(RTCError error) override {
	error_ = std::move(error);
	}

	private:
	// Set on complete, on success this is set to an RTCError::OK() error.
	absl::optional<RTCError> error_;
	};

	class FakeSetRemoteDescriptionObserver
	: public rtc::RefCountedObject<SetRemoteDescriptionObserverInterface> {
	public:
	bool called() const { return error_.has_value(); }
	RTCError& error() {
	RTC_DCHECK(error_.has_value());
	return *error_;
	}

	// SetRemoteDescriptionObserverInterface implementation.
	void OnSetRemoteDescriptionComplete(RTCError error) override {
	error_ = std::move(error);
	}

	private:
	// Set on complete, on success this is set to an RTCError::OK() error.
	absl::optional<RTCError> error_;
	};

	class MockDataChannelObserver : public webrtc::DataChannelObserver {
	public:
	explicit MockDataChannelObserver(webrtc::DataChannelInterface* channel)
	: channel_(channel) {
	channel_->RegisterObserver(this);
	state_ = channel_->state();
	}
	virtual ~MockDataChannelObserver() { channel_->UnregisterObserver(); }

	void OnBufferedAmountChange(uint64_t previous_amount) override {}

	void OnStateChange() override { state_ = channel_->state(); }
	void OnMessage(const DataBuffer& buffer) override {
	messages_.push_back(
	std::string(buffer.data.data<char>(), buffer.data.size()));
	}

	bool IsOpen() const { return state_ == DataChannelInterface::kOpen; }
	std::vector<std::string> messages() const { return messages_; }
	std::string last_message() const {
	return messages_.empty() ? std::string() : messages_.back();
	}
	size_t received_message_count() const { return messages_.size(); }

	private:
	rtc::scoped_refptr<webrtc::DataChannelInterface> channel_;
	DataChannelInterface::DataState state_;
	std::vector<std::string> messages_;
	};

	class MockStatsObserver : public webrtc::StatsObserver {
	public:
	MockStatsObserver() : called_(false), stats_() {}
	virtual ~MockStatsObserver() {}

	virtual void OnComplete(const StatsReports& reports) {
	RTC_CHECK(!called_);
	called_ = true;
	stats_.Clear();
	stats_.number_of_reports = reports.size();
	for (const auto* r : reports) {
	if (r->type() == StatsReport::kStatsReportTypeSsrc) {
	stats_.timestamp = r->timestamp();
	GetIntValue(r, StatsReport::kStatsValueNameAudioOutputLevel,
	&stats_.audio_output_level);
	GetIntValue(r, StatsReport::kStatsValueNameAudioInputLevel,
	&stats_.audio_input_level);
	GetIntValue(r, StatsReport::kStatsValueNameBytesReceived,
	&stats_.bytes_received);
	GetIntValue(r, StatsReport::kStatsValueNameBytesSent,
	&stats_.bytes_sent);
	GetInt64Value(r, StatsReport::kStatsValueNameCaptureStartNtpTimeMs,
	&stats_.capture_start_ntp_time);
	stats_.track_ids.emplace_back();
	GetStringValue(r, StatsReport::kStatsValueNameTrackId,
	&stats_.track_ids.back());
	} else if (r->type() == StatsReport::kStatsReportTypeBwe) {
	stats_.timestamp = r->timestamp();
	GetIntValue(r, StatsReport::kStatsValueNameAvailableReceiveBandwidth,
	&stats_.available_receive_bandwidth);
	} else if (r->type() == StatsReport::kStatsReportTypeComponent) {
	stats_.timestamp = r->timestamp();
	GetStringValue(r, StatsReport::kStatsValueNameDtlsCipher,
	&stats_.dtls_cipher);
	GetStringValue(r, StatsReport::kStatsValueNameSrtpCipher,
	&stats_.srtp_cipher);
	}
	}
	}

	bool called() const { return called_; }
	size_t number_of_reports() const { return stats_.number_of_reports; }
	double timestamp() const { return stats_.timestamp; }

	int AudioOutputLevel() const {
	RTC_CHECK(called_);
	return stats_.audio_output_level;
	}

	int AudioInputLevel() const {
	RTC_CHECK(called_);
	return stats_.audio_input_level;
	}

	int BytesReceived() const {
	RTC_CHECK(called_);
	return stats_.bytes_received;
	}

	int BytesSent() const {
	RTC_CHECK(called_);
	return stats_.bytes_sent;
	}

	int64_t CaptureStartNtpTime() const {
	RTC_CHECK(called_);
	return stats_.capture_start_ntp_time;
	}

	int AvailableReceiveBandwidth() const {
	RTC_CHECK(called_);
	return stats_.available_receive_bandwidth;
	}

	std::string DtlsCipher() const {
	RTC_CHECK(called_);
	return stats_.dtls_cipher;
	}

	std::string SrtpCipher() const {
	RTC_CHECK(called_);
	return stats_.srtp_cipher;
	}

	std::vector<std::string> TrackIds() const {
	RTC_CHECK(called_);
	return stats_.track_ids;
	}

	private:
	bool GetIntValue(const StatsReport* report,
	StatsReport::StatsValueName name,
	int* value) {
	const StatsReport::Value* v = report->FindValue(name);
	if (v) {
	// TODO(tommi): We should really just be using an int here :-/
	*value = rtc::FromString<int>(v->ToString());
	}
	return v != nullptr;
	}

	bool GetInt64Value(const StatsReport* report,
	StatsReport::StatsValueName name,
	int64_t* value) {
	const StatsReport::Value* v = report->FindValue(name);
	if (v) {
	// TODO(tommi): We should really just be using an int here :-/
	*value = rtc::FromString<int64_t>(v->ToString());
	}
	return v != nullptr;
	}

	bool GetStringValue(const StatsReport* report,
	StatsReport::StatsValueName name,
	std::string* value) {
	const StatsReport::Value* v = report->FindValue(name);
	if (v)
	*value = v->ToString();
	return v != nullptr;
	}

	bool called_;
	struct {
	void Clear() {
	number_of_reports = 0;
	timestamp = 0;
	audio_output_level = 0;
	audio_input_level = 0;
	bytes_received = 0;
	bytes_sent = 0;
	capture_start_ntp_time = 0;
	available_receive_bandwidth = 0;
	dtls_cipher.clear();
	srtp_cipher.clear();
	track_ids.clear();
	}

	size_t number_of_reports;
	double timestamp;
	int audio_output_level;
	int audio_input_level;
	int bytes_received;
	int bytes_sent;
	int64_t capture_start_ntp_time;
	int available_receive_bandwidth;
	std::string dtls_cipher;
	std::string srtp_cipher;
	std::vector<std::string> track_ids;
	} stats_;
	};

	// Helper class that just stores the report from the callback.
	class MockRTCStatsCollectorCallback : public webrtc::RTCStatsCollectorCallback {
	public:
	rtc::scoped_refptr<const RTCStatsReport> report() { return report_; }

	bool called() const { return called_; }

	protected:
	void OnStatsDelivered(
	const rtc::scoped_refptr<const RTCStatsReport>& report) override {
	report_ = report;
	called_ = true;
	}

	private:
	bool called_ = false;
	rtc::scoped_refptr<const RTCStatsReport> report_;
	};

	} // namespace webrtc

	#endif // PC_TEST_MOCK_PEER_CONNECTION_OBSERVERS_H_