/*
 *  Copyright (c) 2016 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 <memory>
#include <utility>

#include "testing/gmock/include/gmock/gmock.h"

#include "webrtc/modules/audio_conference_mixer/include/audio_conference_mixer.h"
#include "webrtc/modules/audio_conference_mixer/include/audio_conference_mixer_defines.h"
#include "webrtc/modules/audio_conference_mixer/source/audio_frame_manipulator.h"
#include "webrtc/modules/audio_mixer/audio_mixer.h"
#include "webrtc/modules/audio_mixer/include/audio_mixer_defines.h"
#include "webrtc/modules/audio_mixer/include/new_audio_conference_mixer.h"
#include "webrtc/modules/audio_mixer/source/new_audio_conference_mixer_impl.h"

using testing::_;
using testing::Exactly;
using testing::Invoke;
using testing::Return;

using webrtc::voe::AudioMixer;

namespace webrtc {
class MockAudioMixerParticipant : public MixerParticipant {
 public:
  MockAudioMixerParticipant()
      : fake_audio_frame_info_(MixerParticipant::AudioFrameInfo::kNormal) {
    ON_CALL(*this, GetAudioFrameWithMuted(_, _))
        .WillByDefault(
            Invoke(this, &MockAudioMixerParticipant::FakeAudioFrameWithMuted));
  }

  MOCK_METHOD2(GetAudioFrameWithMuted,
               AudioFrameInfo(const int32_t id, AudioFrame* audio_frame));
  MOCK_CONST_METHOD1(NeededFrequency, int32_t(const int32_t id));

  AudioFrame* fake_frame() { return &fake_frame_; }
  AudioFrameInfo fake_info() { return this->fake_audio_frame_info_; }
  void set_fake_info(const AudioFrameInfo audio_frame_info) {
    fake_audio_frame_info_ = audio_frame_info;
  }

 private:
  AudioFrame fake_frame_;
  AudioFrameInfo fake_audio_frame_info_;
  AudioFrameInfo FakeAudioFrameWithMuted(const int32_t id,
                                         AudioFrame* audio_frame) {
    audio_frame->CopyFrom(*fake_frame());
    return fake_info();
  }
};

class MockMixerAudioSource : public MixerAudioSource {
 public:
  MockMixerAudioSource()
      : fake_audio_frame_info_(MixerAudioSource::AudioFrameInfo::kNormal) {
    ON_CALL(*this, GetAudioFrameWithMuted(_, _))
        .WillByDefault(
            Invoke(this, &MockMixerAudioSource::FakeAudioFrameWithMuted));
  }

  MOCK_METHOD2(GetAudioFrameWithMuted,
               AudioFrameWithMuted(const int32_t id, int sample_rate_hz));

  AudioFrame* fake_frame() { return &fake_frame_; }
  AudioFrameInfo fake_info() { return fake_audio_frame_info_; }
  void set_fake_info(const AudioFrameInfo audio_frame_info) {
    fake_audio_frame_info_ = audio_frame_info;
  }

 private:
  AudioFrame fake_frame_;
  AudioFrameInfo fake_audio_frame_info_;
  AudioFrameWithMuted FakeAudioFrameWithMuted(const int32_t id,
                                              int sample_rate_hz) {
    return {
        fake_frame(),  // audio_frame_pointer
        fake_info(),   // audio_frame_info
    };
  }
};

// Keeps two identical sets of participants and two mixers to test
// that the same participants are chosen for mixing.
class CompareWithOldMixerTest : public testing::Test, AudioMixerOutputReceiver {
 protected:
  constexpr static int kId = 1;
  constexpr static int kSampleRateHz = 32000;

  CompareWithOldMixerTest()
      : old_mixer_(AudioConferenceMixer::Create(kId)),
        new_mixer_(NewAudioConferenceMixer::Create(kId)) {}

  ~CompareWithOldMixerTest() { Reset(); }

  // Mixes with both mixers and compares results: resulting frames and
  // mix statuses.
  void MixAndCompare() {
    old_mixer_->Process();
    new_mixer_->Mix(kSampleRateHz,
                    1,  // number of channels
                    &new_mixer_frame_);
    EXPECT_EQ(0, memcmp(old_mixer_frame_.data_, new_mixer_frame_.data_,
                        sizeof(old_mixer_frame_.data_)));

    for (auto& participant_pair : participants_) {
      EXPECT_EQ(participant_pair.first->IsMixed(),
                participant_pair.second->IsMixed());
    }
  }

  std::unique_ptr<AudioFrame> last_mixed_audio_old() {
    std::unique_ptr<AudioFrame> result(new AudioFrame);
    result->CopyFrom(old_mixer_frame_);
    return result;
  }

  void Reset() {
    old_mixer_.reset(AudioConferenceMixer::Create(kId));
    new_mixer_.reset(NewAudioConferenceMixer::Create(kId));
    for (auto& participant_pair : participants_) {
      delete participant_pair.first;
      delete participant_pair.second;
    }
    participants_.clear();
  }

  void ResetFrame(AudioFrame* audio_frame) {
    audio_frame->sample_rate_hz_ = kSampleRateHz;
    audio_frame->speech_type_ = AudioFrame::kNormalSpeech;
    audio_frame->vad_activity_ = AudioFrame::kVadActive;
    audio_frame->num_channels_ = 1;
  }

  void AddParticipant(AudioFrame* audio_frame,
                      MixerParticipant::AudioFrameInfo audio_frame_info) {
    auto old_participant = new MockAudioMixerParticipant;
    auto new_participant = new MockMixerAudioSource;
    old_participant->fake_frame()->CopyFrom(*audio_frame);
    new_participant->fake_frame()->CopyFrom(*audio_frame);
    old_participant->set_fake_info(audio_frame_info);
    MixerAudioSource::AudioFrameInfo new_audio_frame_info;
    switch (audio_frame_info) {
      case MixerParticipant::AudioFrameInfo::kNormal:
        new_audio_frame_info = MixerAudioSource::AudioFrameInfo::kNormal;
        break;
      case MixerParticipant::AudioFrameInfo::kMuted:
        new_audio_frame_info = MixerAudioSource::AudioFrameInfo::kMuted;
        break;
      default:
        new_audio_frame_info = MixerAudioSource::AudioFrameInfo::kError;
    }
    new_participant->set_fake_info(new_audio_frame_info);
    participants_.emplace_back(old_participant, new_participant);
  }

  void NewMixedAudio(const int32_t id,
                     const AudioFrame& generalAudioFrame,
                     const AudioFrame** uniqueAudioFrames,
                     const uint32_t size) override {
    old_mixer_frame_.CopyFrom(generalAudioFrame);
  }

  AudioFrame old_mixer_frame_;
  AudioFrame new_mixer_frame_;

  std::vector<std::pair<MockAudioMixerParticipant*, MockMixerAudioSource*>>
      participants_;
  std::unique_ptr<AudioConferenceMixer> old_mixer_;
  std::unique_ptr<NewAudioConferenceMixer> new_mixer_;
};

class BothMixersTest : public testing::Test {
 protected:
  BothMixersTest() {
    // Create an OutputMixer.
    AudioMixer::Create(audio_mixer_, kId);

    // Create one mixer participant and add it to the mixer.
    EXPECT_EQ(0, audio_mixer_->SetMixabilityStatus(participant_, true));

    // Each iteration, the participant will return a frame with this content:
    participant_.fake_frame()->id_ = 1;
    participant_.fake_frame()->sample_rate_hz_ = kSampleRateHz;
    participant_.fake_frame()->speech_type_ = AudioFrame::kNormalSpeech;
    participant_.fake_frame()->vad_activity_ = AudioFrame::kVadActive;
    participant_.fake_frame()->num_channels_ = 1;

    // We modify one sample within the RampIn window and one sample
    // outside of it.
    participant_.fake_frame()->data_[10] = 100;
    participant_.fake_frame()->data_[20] = -200;
    participant_.fake_frame()->data_[30] = 300;
    participant_.fake_frame()->data_[90] = -400;

    // Frame duration 10ms.
    participant_.fake_frame()->samples_per_channel_ = kSampleRateHz / 100;
  }

  ~BothMixersTest() { AudioMixer::Destroy(audio_mixer_); }

  // Mark the participant as 'unmixed' last round.
  void ResetAudioSource() { participant_._mixHistory->SetIsMixed(false); }

  AudioMixer* audio_mixer_;
  MockMixerAudioSource participant_;
  AudioFrame mixing_round_frame, mixed_results_frame_;

  constexpr static int kSampleRateHz = 48000;
  constexpr static int kId = 1;
};

TEST(AudioMixer, AnonymousAndNamed) {
  constexpr int kId = 1;
  // Should not matter even if partipants are more than
  // kMaximumAmountOfMixedAudioSources.
  constexpr int kNamed =
      NewAudioConferenceMixer::kMaximumAmountOfMixedAudioSources + 1;
  constexpr int kAnonymous =
      NewAudioConferenceMixer::kMaximumAmountOfMixedAudioSources + 1;

  std::unique_ptr<NewAudioConferenceMixer> mixer(
      NewAudioConferenceMixer::Create(kId));

  MockMixerAudioSource named[kNamed];
  MockMixerAudioSource anonymous[kAnonymous];

  for (int i = 0; i < kNamed; ++i) {
    EXPECT_EQ(0, mixer->SetMixabilityStatus(&named[i], true));
    EXPECT_TRUE(mixer->MixabilityStatus(named[i]));
  }

  for (int i = 0; i < kAnonymous; ++i) {
    // AudioSource must be registered before turning it into anonymous.
    EXPECT_EQ(-1, mixer->SetAnonymousMixabilityStatus(&anonymous[i], true));
    EXPECT_EQ(0, mixer->SetMixabilityStatus(&anonymous[i], true));
    EXPECT_TRUE(mixer->MixabilityStatus(anonymous[i]));
    EXPECT_FALSE(mixer->AnonymousMixabilityStatus(anonymous[i]));

    EXPECT_EQ(0, mixer->SetAnonymousMixabilityStatus(&anonymous[i], true));
    EXPECT_TRUE(mixer->AnonymousMixabilityStatus(anonymous[i]));

    // Anonymous participants do not show status by MixabilityStatus.
    EXPECT_FALSE(mixer->MixabilityStatus(anonymous[i]));
  }

  for (int i = 0; i < kNamed; ++i) {
    EXPECT_EQ(0, mixer->SetMixabilityStatus(&named[i], false));
    EXPECT_FALSE(mixer->MixabilityStatus(named[i]));
  }

  for (int i = 0; i < kAnonymous - 1; i++) {
    EXPECT_EQ(0, mixer->SetAnonymousMixabilityStatus(&anonymous[i], false));
    EXPECT_FALSE(mixer->AnonymousMixabilityStatus(anonymous[i]));

    // SetAnonymousMixabilityStatus(anonymous, false) moves anonymous to the
    // named group.
    EXPECT_TRUE(mixer->MixabilityStatus(anonymous[i]));
  }

  // SetMixabilityStatus(anonymous, false) will remove anonymous from both
  // anonymous and named groups.
  EXPECT_EQ(0, mixer->SetMixabilityStatus(&anonymous[kAnonymous - 1], false));
  EXPECT_FALSE(mixer->AnonymousMixabilityStatus(anonymous[kAnonymous - 1]));
  EXPECT_FALSE(mixer->MixabilityStatus(anonymous[kAnonymous - 1]));
}

TEST(AudioMixer, LargestEnergyVadActiveMixed) {
  const int kId = 1;
  const int kAudioSources =
      NewAudioConferenceMixer::kMaximumAmountOfMixedAudioSources + 3;
  const int kSampleRateHz = 32000;

  std::unique_ptr<NewAudioConferenceMixer> mixer(
      NewAudioConferenceMixer::Create(kId));

  MockMixerAudioSource participants[kAudioSources];

  for (int i = 0; i < kAudioSources; ++i) {
    participants[i].fake_frame()->id_ = i;
    participants[i].fake_frame()->sample_rate_hz_ = kSampleRateHz;
    participants[i].fake_frame()->speech_type_ = AudioFrame::kNormalSpeech;
    participants[i].fake_frame()->vad_activity_ = AudioFrame::kVadActive;
    participants[i].fake_frame()->num_channels_ = 1;

    // Frame duration 10ms.
    participants[i].fake_frame()->samples_per_channel_ = kSampleRateHz / 100;

    // We set the 80-th sample value since the first 80 samples may be
    // modified by a ramped-in window.
    participants[i].fake_frame()->data_[80] = i;

    EXPECT_EQ(0, mixer->SetMixabilityStatus(&participants[i], true));
    EXPECT_CALL(participants[i], GetAudioFrameWithMuted(_, _))
        .Times(Exactly(1));
  }

  // Last participant gives audio frame with passive VAD, although it has the
  // largest energy.
  participants[kAudioSources - 1].fake_frame()->vad_activity_ =
      AudioFrame::kVadPassive;

  AudioFrame audio_frame;
  mixer->Mix(kSampleRateHz,
             1,  // number of channels
             &audio_frame);

  for (int i = 0; i < kAudioSources; ++i) {
    bool is_mixed = participants[i].IsMixed();
    if (i == kAudioSources - 1 ||
        i < kAudioSources - 1 -
                NewAudioConferenceMixer::kMaximumAmountOfMixedAudioSources) {
      EXPECT_FALSE(is_mixed) << "Mixing status of AudioSource #" << i
                             << " wrong.";
    } else {
      EXPECT_TRUE(is_mixed) << "Mixing status of AudioSource #" << i
                            << " wrong.";
    }
  }
}

TEST(AudioMixer, ParticipantSampleRate) {
  const int kId = 1;
  std::unique_ptr<NewAudioConferenceMixer> mixer(
      NewAudioConferenceMixer::Create(kId));
  AudioFrame frame_for_mixing;

  MockMixerAudioSource participant;
  participant.fake_frame()->sample_rate_hz_ = 8000;
  participant.fake_frame()->num_channels_ = 1;

  // Frame duration 10ms.
  participant.fake_frame()->samples_per_channel_ = 8000 / 100;

  EXPECT_EQ(0, mixer->SetMixabilityStatus(&participant, true));
  for (auto frequency : {8000, 16000, 32000, 48000}) {
    EXPECT_CALL(participant, GetAudioFrameWithMuted(_, frequency))
        .Times(Exactly(1));
    mixer->Mix(frequency, 1, &frame_for_mixing);
    EXPECT_EQ(frequency, frame_for_mixing.sample_rate_hz_);
  }
}

TEST(AudioMixer, ParticipantNumberOfChannels) {
  const int kId = 1;
  std::unique_ptr<NewAudioConferenceMixer> mixer(
      NewAudioConferenceMixer::Create(kId));
  AudioFrame frame_for_mixing;

  MockMixerAudioSource participant;
  participant.fake_frame()->sample_rate_hz_ = 8000;
  participant.fake_frame()->num_channels_ = 1;

  // Frame duration 10ms.
  participant.fake_frame()->samples_per_channel_ = 8000 / 100;

  EXPECT_EQ(0, mixer->SetMixabilityStatus(&participant, true));
  for (size_t number_of_channels : {1, 2}) {
    EXPECT_CALL(participant, GetAudioFrameWithMuted(_, 8000)).Times(Exactly(1));
    mixer->Mix(8000, number_of_channels, &frame_for_mixing);
    EXPECT_EQ(number_of_channels, frame_for_mixing.num_channels_);
  }
}

TEST_F(BothMixersTest, CompareInitialFrameAudio) {
  EXPECT_CALL(participant_, GetAudioFrameWithMuted(_, _)).Times(Exactly(1));

  // Make sure the participant is marked as 'non-mixed' so that it is
  // ramped in next round.
  ResetAudioSource();

  // Construct the expected sound for the first mixing round.
  mixing_round_frame.CopyFrom(*participant_.fake_frame());
  RampIn(mixing_round_frame);

  // Mix frames and put the result into a frame.
  audio_mixer_->GetMixedAudio(kSampleRateHz, 1, &mixed_results_frame_);

  // Compare the received frame with the expected.
  EXPECT_EQ(mixing_round_frame.sample_rate_hz_,
            mixed_results_frame_.sample_rate_hz_);
  EXPECT_EQ(mixing_round_frame.num_channels_,
            mixed_results_frame_.num_channels_);
  EXPECT_EQ(mixing_round_frame.samples_per_channel_,
            mixed_results_frame_.samples_per_channel_);
  EXPECT_EQ(0, memcmp(mixing_round_frame.data_, mixed_results_frame_.data_,
                      sizeof(mixing_round_frame.data_)));
}

TEST_F(BothMixersTest, CompareSecondFrameAudio) {
  EXPECT_CALL(participant_, GetAudioFrameWithMuted(_, _)).Times(Exactly(2));

  // Make sure the participant is marked as 'non-mixed' so that it is
  // ramped in next round.
  ResetAudioSource();

  // Do one mixing iteration.
  audio_mixer_->GetMixedAudio(kSampleRateHz, 1, &mixed_results_frame_);

  // Mix frames a second time and compare with the expected frame
  // (which is the participant's frame).
  audio_mixer_->GetMixedAudio(kSampleRateHz, 1, &mixed_results_frame_);
  EXPECT_EQ(0,
            memcmp(participant_.fake_frame()->data_, mixed_results_frame_.data_,
                   sizeof(mixing_round_frame.data_)));
}

TEST_F(CompareWithOldMixerTest, TwoParticipantsNormalFrames) {
  Reset();
  AudioFrame first_frame, second_frame;

  ResetFrame(&first_frame);
  ResetFrame(&second_frame);

  first_frame.id_ = 1;
  second_frame.id_ = 2;

  AddParticipant(&first_frame, MixerParticipant::AudioFrameInfo::kNormal);
  AddParticipant(&second_frame, MixerParticipant::AudioFrameInfo::kNormal);

  for (int i = 0; i < 3; ++i) {
    MixAndCompare();
  }
}

TEST_F(CompareWithOldMixerTest, ThreeParticipantsDifferentFrames) {
  Reset();
  AudioFrame first_frame, second_frame, third_frame;

  ResetFrame(&first_frame);
  ResetFrame(&second_frame);
  ResetFrame(&third_frame);

  first_frame.id_ = 1;
  second_frame.id_ = 2;
  third_frame.id_ = 3;
  second_frame.vad_activity_ = AudioFrame::kVadPassive;

  AddParticipant(&first_frame, MixerParticipant::AudioFrameInfo::kNormal);
  AddParticipant(&second_frame, MixerParticipant::AudioFrameInfo::kMuted);
  AddParticipant(&third_frame, MixerParticipant::AudioFrameInfo::kMuted);

  for (int i = 0; i < 3; ++i) {
    MixAndCompare();
  }
}

TEST_F(CompareWithOldMixerTest, ManyParticipantsDifferentFrames) {
  Reset();
  constexpr int num_participants = 20;
  AudioFrame audio_frames[num_participants];

  for (int i = 0; i < num_participants; ++i) {
    ResetFrame(&audio_frames[i]);
    audio_frames[i].id_ = 1;
    audio_frames[i].data_[10] = 100 * (i % 5);
    audio_frames[i].data_[100] = 100 * (i % 5);
    if (i % 2 == 0) {
      audio_frames[i].vad_activity_ = AudioFrame::kVadPassive;
    }
  }

  for (int i = 0; i < num_participants; ++i) {
    if (i % 2 == 0) {
      AddParticipant(&audio_frames[i],
                     MixerParticipant::AudioFrameInfo::kMuted);
    } else {
      AddParticipant(&audio_frames[i],
                     MixerParticipant::AudioFrameInfo::kNormal);
    }
    MixAndCompare();
  }
}

}  // namespace webrtc