/*
 *  Copyright (c) 2019 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 "test/peer_scenario/peer_scenario_client.h"

#include <limits>
#include <utility>

#include "absl/memory/memory.h"
#include "api/audio_codecs/builtin_audio_decoder_factory.h"
#include "api/audio_codecs/builtin_audio_encoder_factory.h"
#include "api/rtc_event_log/rtc_event_log_factory.h"
#include "api/task_queue/default_task_queue_factory.h"
#include "api/video_codecs/builtin_video_decoder_factory.h"
#include "api/video_codecs/builtin_video_encoder_factory.h"
#include "media/engine/webrtc_media_engine.h"
#include "modules/audio_device/include/test_audio_device.h"
#include "p2p/client/basic_port_allocator.h"
#include "test/frame_generator_capturer.h"
#include "test/peer_scenario/sdp_callbacks.h"

namespace webrtc {
namespace test {

namespace {

constexpr char kCommonStreamId[] = "stream_id";

std::map<int, EmulatedEndpoint*> CreateEndpoints(
    NetworkEmulationManager* net,
    std::map<int, EmulatedEndpointConfig> endpoint_configs) {
  std::map<int, EmulatedEndpoint*> endpoints;
  for (const auto& kv : endpoint_configs)
    endpoints[kv.first] = net->CreateEndpoint(kv.second);
  return endpoints;
}

class LambdaPeerConnectionObserver final : public PeerConnectionObserver {
 public:
  explicit LambdaPeerConnectionObserver(
      PeerScenarioClient::CallbackHandlers* handlers)
      : handlers_(handlers) {}
  void OnSignalingChange(
      PeerConnectionInterface::SignalingState new_state) override {
    for (const auto& handler : handlers_->on_signaling_change)
      handler(new_state);
  }
  void OnDataChannel(
      rtc::scoped_refptr<DataChannelInterface> data_channel) override {
    for (const auto& handler : handlers_->on_data_channel)
      handler(data_channel);
  }
  void OnRenegotiationNeeded() override {
    for (const auto& handler : handlers_->on_renegotiation_needed)
      handler();
  }
  void OnStandardizedIceConnectionChange(
      PeerConnectionInterface::IceConnectionState new_state) override {
    for (const auto& handler : handlers_->on_standardized_ice_connection_change)
      handler(new_state);
  }
  void OnConnectionChange(
      PeerConnectionInterface::PeerConnectionState new_state) override {
    for (const auto& handler : handlers_->on_connection_change)
      handler(new_state);
  }
  void OnIceGatheringChange(
      PeerConnectionInterface::IceGatheringState new_state) override {
    for (const auto& handler : handlers_->on_ice_gathering_change)
      handler(new_state);
  }
  void OnIceCandidate(const IceCandidateInterface* candidate) override {
    for (const auto& handler : handlers_->on_ice_candidate)
      handler(candidate);
  }
  void OnIceCandidateError(const std::string& host_candidate,
                           const std::string& url,
                           int error_code,
                           const std::string& error_text) override {
    for (const auto& handler : handlers_->on_ice_candidate_error)
      handler(host_candidate, url, error_code, error_text);
  }
  void OnIceCandidatesRemoved(
      const std::vector<cricket::Candidate>& candidates) override {
    for (const auto& handler : handlers_->on_ice_candidates_removed)
      handler(candidates);
  }
  void OnAddTrack(rtc::scoped_refptr<RtpReceiverInterface> receiver,
                  const std::vector<rtc::scoped_refptr<MediaStreamInterface> >&
                      streams) override {
    for (const auto& handler : handlers_->on_add_track)
      handler(receiver, streams);
  }
  void OnTrack(
      rtc::scoped_refptr<RtpTransceiverInterface> transceiver) override {
    for (const auto& handler : handlers_->on_track)
      handler(transceiver);
  }
  void OnRemoveTrack(
      rtc::scoped_refptr<RtpReceiverInterface> receiver) override {
    for (const auto& handler : handlers_->on_remove_track)
      handler(receiver);
  }

 private:
  PeerScenarioClient::CallbackHandlers* handlers_;
};
}  // namespace

PeerScenarioClient::PeerScenarioClient(NetworkEmulationManager* net,
                                       rtc::Thread* signaling_thread,
                                       PeerScenarioClient::Config config)
    : endpoints_(CreateEndpoints(net, config.endpoints)),
      signaling_thread_(signaling_thread),
      worker_thread_(rtc::Thread::Create()),
      handlers_(config.handlers),
      observer_(new LambdaPeerConnectionObserver(&handlers_)) {
  worker_thread_->SetName("worker", this);
  worker_thread_->Start();

  handlers_.on_track.push_back(
      [this](rtc::scoped_refptr<RtpTransceiverInterface> transceiver) {
        auto track = transceiver->receiver()->track().get();
        if (track->kind() == MediaStreamTrackInterface::kVideoKind) {
          auto* video = static_cast<VideoTrackInterface*>(track);
          RTC_DCHECK_RUN_ON(signaling_thread_);
          for (auto* sink : track_id_to_video_sinks_[track->id()]) {
            video->AddOrUpdateSink(sink, rtc::VideoSinkWants());
          }
        }
      });
  handlers_.on_signaling_change.push_back(
      [this](PeerConnectionInterface::SignalingState state) {
        if (state == PeerConnectionInterface::SignalingState::kStable &&
            peer_connection_->current_remote_description()) {
          RTC_DCHECK_RUN_ON(signaling_thread_);
          for (const auto& candidate : pending_ice_candidates_) {
            RTC_CHECK(peer_connection_->AddIceCandidate(candidate.get()));
          }
          pending_ice_candidates_.clear();
        }
      });

  std::vector<EmulatedEndpoint*> endpoints_vector;
  for (const auto& kv : endpoints_)
    endpoints_vector.push_back(kv.second);
  auto* manager = net->CreateEmulatedNetworkManagerInterface(endpoints_vector);

  PeerConnectionFactoryDependencies pcf_deps;
  pcf_deps.network_thread = manager->network_thread();
  pcf_deps.signaling_thread = signaling_thread_;
  pcf_deps.worker_thread = worker_thread_.get();
  pcf_deps.call_factory = CreateCallFactory();
  pcf_deps.task_queue_factory = CreateDefaultTaskQueueFactory();
  task_queue_factory_ = pcf_deps.task_queue_factory.get();
  pcf_deps.event_log_factory =
      absl::make_unique<RtcEventLogFactory>(task_queue_factory_);

  cricket::MediaEngineDependencies media_deps;
  media_deps.task_queue_factory = task_queue_factory_;
  media_deps.adm = TestAudioDeviceModule::Create(
      task_queue_factory_,
      TestAudioDeviceModule::CreatePulsedNoiseCapturer(
          config.audio.pulsed_noise->amplitude *
              std::numeric_limits<int16_t>::max(),
          config.audio.sample_rate, config.audio.channels),
      TestAudioDeviceModule::CreateDiscardRenderer(config.audio.sample_rate));

  media_deps.audio_processing = AudioProcessingBuilder().Create();
  media_deps.video_encoder_factory = CreateBuiltinVideoEncoderFactory();
  media_deps.video_decoder_factory = CreateBuiltinVideoDecoderFactory();
  media_deps.audio_encoder_factory = CreateBuiltinAudioEncoderFactory();
  media_deps.audio_decoder_factory = CreateBuiltinAudioDecoderFactory();

  pcf_deps.media_engine = cricket::CreateMediaEngine(std::move(media_deps));
  pcf_deps.fec_controller_factory = nullptr;
  pcf_deps.network_controller_factory = nullptr;
  pcf_deps.network_state_predictor_factory = nullptr;
  pcf_deps.media_transport_factory = nullptr;

  pc_factory_ = CreateModularPeerConnectionFactory(std::move(pcf_deps));

  PeerConnectionDependencies pc_deps(observer_.get());
  pc_deps.allocator = absl::make_unique<cricket::BasicPortAllocator>(
      manager->network_manager());
  pc_deps.allocator->set_flags(pc_deps.allocator->flags() |
                               cricket::PORTALLOCATOR_DISABLE_TCP);
  peer_connection_ =
      pc_factory_->CreatePeerConnection(config.rtc_config, std::move(pc_deps));
}

EmulatedEndpoint* PeerScenarioClient::endpoint(int index) {
  RTC_CHECK_GT(endpoints_.size(), index);
  return endpoints_.at(index);
}

PeerScenarioClient::AudioSendTrack PeerScenarioClient::CreateAudio(
    std::string track_id,
    cricket::AudioOptions options) {
  AudioSendTrack res;
  auto source = pc_factory_->CreateAudioSource(options);
  auto track = pc_factory_->CreateAudioTrack(track_id, source);
  res.track = track;
  res.sender = peer_connection_->AddTrack(track, {kCommonStreamId}).value();
  return res;
}

PeerScenarioClient::VideoSendTrack PeerScenarioClient::CreateVideo(
    std::string track_id,
    VideoSendTrackConfig config) {
  VideoSendTrack res;
  auto capturer = FrameGeneratorCapturer::Create(clock(), *task_queue_factory_,
                                                 config.generator);
  res.capturer = capturer.get();
  capturer->Init();
  res.source =
      new rtc::RefCountedObject<FrameGeneratorCapturerVideoTrackSource>(
          std::move(capturer), config.screencast);
  auto track = pc_factory_->CreateVideoTrack(track_id, res.source);
  res.track = track;
  res.sender = peer_connection_->AddTrack(track, {kCommonStreamId}).MoveValue();
  return res;
}

void PeerScenarioClient::AddVideoReceiveSink(
    std::string track_id,
    rtc::VideoSinkInterface<VideoFrame>* video_sink) {
  RTC_DCHECK_RUN_ON(signaling_thread_);
  track_id_to_video_sinks_[track_id].push_back(video_sink);
}

void PeerScenarioClient::CreateAndSetSdp(
    std::function<void(std::string)> offer_handler) {
  peer_connection_->CreateOffer(
      SdpCreateObserver([=](SessionDescriptionInterface* offer) {
        std::string sdp_offer;
        offer->ToString(&sdp_offer);
        printf("%s\n", sdp_offer.c_str());
        peer_connection_->SetLocalDescription(
            SdpSetObserver([sdp_offer, offer_handler]() {
              offer_handler(std::move(sdp_offer));
            }),
            offer);
      }),
      PeerConnectionInterface::RTCOfferAnswerOptions());
}

void PeerScenarioClient::SetSdpOfferAndGetAnswer(
    std::string remote_offer,
    std::function<void(std::string)> answer_handler) {
  peer_connection_->SetRemoteDescription(
      CreateSessionDescription(SdpType::kOffer, remote_offer),
      SdpSetObserver([=]() {
        peer_connection_->CreateAnswer(
            SdpCreateObserver([=](SessionDescriptionInterface* answer) {
              std::string sdp_answer;
              answer->ToString(&sdp_answer);
              printf("%s\n", sdp_answer.c_str());
              peer_connection_->SetLocalDescription(
                  SdpSetObserver([answer_handler, sdp_answer]() {
                    answer_handler(sdp_answer);
                  }),
                  answer);
            }),
            PeerConnectionInterface::RTCOfferAnswerOptions());
      }));
}

void PeerScenarioClient::SetSdpAnswer(
    std::string remote_answer,
    std::function<void(const SessionDescriptionInterface&)> done_handler) {
  peer_connection_->SetRemoteDescription(
      CreateSessionDescription(SdpType::kAnswer, remote_answer),
      SdpSetObserver([remote_answer, done_handler] {
        auto answer = CreateSessionDescription(SdpType::kAnswer, remote_answer);
        done_handler(*answer);
      }));
}

void PeerScenarioClient::AddIceCandidate(
    std::unique_ptr<IceCandidateInterface> candidate) {
  if (peer_connection_->signaling_state() ==
          PeerConnectionInterface::SignalingState::kStable &&
      peer_connection_->current_remote_description()) {
    RTC_CHECK(peer_connection_->AddIceCandidate(candidate.get()));
  } else {
    RTC_DCHECK_RUN_ON(signaling_thread_);
    pending_ice_candidates_.push_back(std::move(candidate));
  }
}

}  // namespace test
}  // namespace webrtc