// Copyright 2018 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "services/media_session/audio_focus_manager.h"

#include <algorithm>
#include <memory>
#include <utility>
#include <vector>

#include "base/containers/adapters.h"
#include "base/functional/bind.h"
#include "base/functional/callback.h"
#include "base/run_loop.h"
#include "base/test/power_monitor_test.h"
#include "base/test/task_environment.h"
#include "build/build_config.h"
#include "mojo/public/cpp/bindings/remote.h"
#include "services/media_session/audio_focus_request.h"
#include "services/media_session/media_session_service_impl.h"
#include "services/media_session/public/cpp/test/audio_focus_test_util.h"
#include "services/media_session/public/cpp/test/mock_media_session.h"
#include "services/media_session/public/mojom/audio_focus.mojom.h"
#include "services/media_session/public/mojom/media_session.mojom.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace media_session {

namespace {

const char kExampleSourceName[] = "test";
const char kExampleSourceName2[] = "test2";

}  // anonymous namespace

// This tests the Audio Focus Manager API. The parameter determines whether
// audio focus is enabled or not. If it is not enabled it should track the media
// sessions but not enforce single session focus.
class AudioFocusManagerTest
    : public testing::TestWithParam<mojom::EnforcementMode> {
 public:
  AudioFocusManagerTest() = default;

  AudioFocusManagerTest(const AudioFocusManagerTest&) = delete;
  AudioFocusManagerTest& operator=(const AudioFocusManagerTest&) = delete;

  void SetUp() override {
    // Create an instance of the MediaSessionService.
    service_ = std::make_unique<MediaSessionServiceImpl>();
    service_->BindAudioFocusManager(
        audio_focus_remote_.BindNewPipeAndPassReceiver());
    service_->BindAudioFocusManagerDebug(
        audio_focus_debug_remote_.BindNewPipeAndPassReceiver());
    service_->BindMediaControllerManager(
        controller_manager_remote_.BindNewPipeAndPassReceiver());

    audio_focus_remote_->SetEnforcementMode(GetParam());
    audio_focus_remote_.FlushForTesting();
  }

  void TearDown() override {
    // Run pending tasks.
    base::RunLoop().RunUntilIdle();

    service_.reset();
  }

  AudioFocusManager::RequestId GetAudioFocusedSession() {
    const auto audio_focus_requests = GetRequests();
    for (const auto& request : base::Reversed(audio_focus_requests)) {
      if (request->audio_focus_type == mojom::AudioFocusType::kGain)
        return request->request_id.value();
    }
    return base::UnguessableToken::Null();
  }

  int GetTransientCount() {
    return GetCountForType(mojom::AudioFocusType::kGainTransient);
  }

  int GetTransientMaybeDuckCount() {
    return GetCountForType(mojom::AudioFocusType::kGainTransientMayDuck);
  }

  int GetAmbientCount() {
    return GetCountForType(mojom::AudioFocusType::kAmbient);
  }

  void AbandonAudioFocusNoReset(test::MockMediaSession* session) {
    session->audio_focus_request()->AbandonAudioFocus();
    session->FlushForTesting();
    audio_focus_remote_.FlushForTesting();
  }

  AudioFocusManager::RequestId RequestAudioFocus(
      test::MockMediaSession* session,
      mojom::AudioFocusType audio_focus_type) {
    return session->RequestAudioFocusFromService(audio_focus_remote_,
                                                 audio_focus_type);
  }

  bool RequestGroupedAudioFocus(const base::UnguessableToken& request_id,
                                test::MockMediaSession* session,
                                mojom::AudioFocusType audio_focus_type,
                                const base::UnguessableToken& group_id) {
    return session->RequestGroupedAudioFocusFromService(
        request_id, audio_focus_remote_, audio_focus_type, group_id);
  }

  mojom::MediaSessionDebugInfoPtr GetDebugInfo(
      AudioFocusManager::RequestId request_id) {
    mojom::MediaSessionDebugInfoPtr result;
    base::OnceCallback<void(mojom::MediaSessionDebugInfoPtr)> callback =
        base::BindOnce(
            [](mojom::MediaSessionDebugInfoPtr* out_result,
               mojom::MediaSessionDebugInfoPtr result) {
              *out_result = std::move(result);
            },
            &result);

    GetDebugService()->GetDebugInfoForRequest(request_id, std::move(callback));

    audio_focus_remote_.FlushForTesting();
    audio_focus_debug_remote_.FlushForTesting();

    return result;
  }

  mojom::MediaSessionInfo::SessionState GetState(
      test::MockMediaSession* session) {
    mojom::MediaSessionInfo::SessionState state = session->GetState();

    return state;
  }

  std::unique_ptr<test::TestAudioFocusObserver> CreateObserver() {
    std::unique_ptr<test::TestAudioFocusObserver> observer =
        std::make_unique<test::TestAudioFocusObserver>();

    GetService()->AddObserver(observer->BindNewPipeAndPassRemote());

    audio_focus_remote_.FlushForTesting();
    return observer;
  }

  std::unique_ptr<test::TestAudioFocusObserver> CreateSourceObserver(
      const base::UnguessableToken& source_id) {
    std::unique_ptr<test::TestAudioFocusObserver> observer =
        std::make_unique<test::TestAudioFocusObserver>();

    GetService()->AddSourceObserver(source_id,
                                    observer->BindNewPipeAndPassRemote());

    audio_focus_remote_.FlushForTesting();
    return observer;
  }

  mojom::MediaSessionInfo::SessionState GetStateFromParam(
      mojom::MediaSessionInfo::SessionState state) {
    // If enforcement is enabled then returns the provided state, otherwise
    // returns kActive because without enforcement we did not change state.
    if (IsEnforcementEnabled())
      return state;
    return mojom::MediaSessionInfo::SessionState::kActive;
  }

  void SetSource(const base::UnguessableToken& identity,
                 const std::string& name) {
    GetService()->SetSource(identity, name);
    audio_focus_remote_.FlushForTesting();
  }

  mojo::Remote<mojom::AudioFocusManager> CreateAudioFocusManagerRemote() {
    mojo::Remote<mojom::AudioFocusManager> remote;
    service_->BindAudioFocusManager(remote.BindNewPipeAndPassReceiver());
    return remote;
  }

  const std::string GetSourceNameForLastRequest() {
    std::vector<mojom::AudioFocusRequestStatePtr> requests = GetRequests();
    EXPECT_TRUE(requests.back());
    return requests.back()->source_name.value();
  }

  bool IsEnforcementEnabled() const {
#if BUILDFLAG(IS_CHROMEOS)
    // Enforcement is enabled by default on Chrome OS.
    if (GetParam() == mojom::EnforcementMode::kDefault)
      return true;
#endif

    return GetParam() == mojom::EnforcementMode::kSingleSession ||
           GetParam() == mojom::EnforcementMode::kSingleGroup;
  }

  bool IsGroupingEnabled() const {
    return GetParam() != mojom::EnforcementMode::kSingleSession;
  }

  void GenerateSuspendEvent() { power_source_.GenerateSuspendEvent(); }

  mojo::Remote<mojom::MediaControllerManager>& controller_manager() {
    return controller_manager_remote_;
  }

  std::vector<mojom::AudioFocusRequestStatePtr> GetSourceFocusRequests(
      const base::UnguessableToken& source_id) {
    std::vector<mojom::AudioFocusRequestStatePtr> result;

    GetService()->GetSourceFocusRequests(
        source_id,
        base::BindOnce(
            [](std::vector<mojom::AudioFocusRequestStatePtr>* out,
               std::vector<mojom::AudioFocusRequestStatePtr> requests) {
              *out = std::move(requests);
            },
            &result));

    audio_focus_remote_.FlushForTesting();
    return result;
  }

  const base::UnguessableToken& GetIdentityForLastRequest() const {
    return service_->audio_focus_manager_for_testing()
        .audio_focus_stack_.back()
        ->identity();
  }

  void StartDuckingAllAudio(
      const std::optional<base::UnguessableToken>& exempted_request_id) {
    GetService()->StartDuckingAllAudio(exempted_request_id);
    FlushForTesting();
  }

  void StopDuckingAllAudio() {
    GetService()->StopDuckingAllAudio();
    FlushForTesting();
  }

  void FlushForTesting() { audio_focus_remote_.FlushForTesting(); }

 private:
  int GetCountForType(mojom::AudioFocusType type) {
    const auto audio_focus_requests = GetRequests();
    return std::ranges::count(audio_focus_requests, type,
                              &mojom::AudioFocusRequestState::audio_focus_type);
  }

  std::vector<mojom::AudioFocusRequestStatePtr> GetRequests() {
    std::vector<mojom::AudioFocusRequestStatePtr> result;

    GetService()->GetFocusRequests(base::BindOnce(
        [](std::vector<mojom::AudioFocusRequestStatePtr>* out,
           std::vector<mojom::AudioFocusRequestStatePtr> requests) {
          for (auto& request : requests)
            out->push_back(request.Clone());
        },
        &result));

    audio_focus_remote_.FlushForTesting();
    return result;
  }

  mojom::AudioFocusManager* GetService() const {
    return audio_focus_remote_.get();
  }

  mojom::AudioFocusManagerDebug* GetDebugService() const {
    return audio_focus_debug_remote_.get();
  }

  void FlushForTestingIfEnabled() {
    if (!IsEnforcementEnabled())
      return;

    audio_focus_remote_.FlushForTesting();
  }

  base::test::TaskEnvironment task_environment_;

  std::unique_ptr<MediaSessionServiceImpl> service_;

  mojo::Remote<mojom::AudioFocusManager> audio_focus_remote_;
  mojo::Remote<mojom::AudioFocusManagerDebug> audio_focus_debug_remote_;
  mojo::Remote<mojom::MediaControllerManager> controller_manager_remote_;

  base::test::ScopedPowerMonitorTestSource power_source_;
};

INSTANTIATE_TEST_SUITE_P(
    All,
    AudioFocusManagerTest,
    testing::Values(mojom::EnforcementMode::kDefault,
                    mojom::EnforcementMode::kNone,
                    mojom::EnforcementMode::kSingleGroup,
                    mojom::EnforcementMode::kSingleSession));

TEST_P(AudioFocusManagerTest, RequestAudioFocusGain_ReplaceFocusedEntry) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;
  test::MockMediaSession media_session_3;

  EXPECT_EQ(base::UnguessableToken::Null(), GetAudioFocusedSession());
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kInactive,
            GetState(&media_session_1));
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kInactive,
            GetState(&media_session_2));
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kInactive,
            GetState(&media_session_3));

  AudioFocusManager::RequestId request_id_1 =
      RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(request_id_1, GetAudioFocusedSession());
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));

  AudioFocusManager::RequestId request_id_2 =
      RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGain);
  EXPECT_EQ(request_id_2, GetAudioFocusedSession());
  EXPECT_EQ(
      GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended),
      GetState(&media_session_1));

  AudioFocusManager::RequestId request_id_3 =
      RequestAudioFocus(&media_session_3, mojom::AudioFocusType::kGain);
  EXPECT_EQ(request_id_3, GetAudioFocusedSession());
  EXPECT_EQ(
      GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended),
      GetState(&media_session_2));
}

TEST_P(AudioFocusManagerTest, RequestAudioFocusGain_Duplicate) {
  test::MockMediaSession media_session;

  EXPECT_EQ(base::UnguessableToken::Null(), GetAudioFocusedSession());

  AudioFocusManager::RequestId request_id =
      RequestAudioFocus(&media_session, mojom::AudioFocusType::kGain);
  EXPECT_EQ(request_id, GetAudioFocusedSession());

  RequestAudioFocus(&media_session, mojom::AudioFocusType::kGain);
  EXPECT_EQ(request_id, GetAudioFocusedSession());
}

TEST_P(AudioFocusManagerTest, RequestAudioFocusGain_FromTransient) {
  test::MockMediaSession media_session;

  AudioFocusManager::RequestId request_id =
      RequestAudioFocus(&media_session, mojom::AudioFocusType::kGainTransient);
  EXPECT_EQ(base::UnguessableToken::Null(), GetAudioFocusedSession());
  EXPECT_EQ(1, GetTransientCount());

  RequestAudioFocus(&media_session, mojom::AudioFocusType::kGain);
  EXPECT_EQ(request_id, GetAudioFocusedSession());
  EXPECT_EQ(0, GetTransientCount());
}

TEST_P(AudioFocusManagerTest, RequestAudioFocusGain_FromTransientMayDuck) {
  test::MockMediaSession media_session;

  AudioFocusManager::RequestId request_id = RequestAudioFocus(
      &media_session, mojom::AudioFocusType::kGainTransientMayDuck);
  EXPECT_EQ(base::UnguessableToken::Null(), GetAudioFocusedSession());
  EXPECT_EQ(1, GetTransientMaybeDuckCount());

  RequestAudioFocus(&media_session, mojom::AudioFocusType::kGain);
  EXPECT_EQ(request_id, GetAudioFocusedSession());
  EXPECT_EQ(0, GetTransientMaybeDuckCount());
}

TEST_P(AudioFocusManagerTest, RequestAudioFocusTransient_FromGain) {
  test::MockMediaSession media_session;

  AudioFocusManager::RequestId request_id =
      RequestAudioFocus(&media_session, mojom::AudioFocusType::kGain);

  EXPECT_EQ(request_id, GetAudioFocusedSession());
  EXPECT_EQ(0, GetTransientCount());

  RequestAudioFocus(&media_session, mojom::AudioFocusType::kGainTransient);
  EXPECT_EQ(base::UnguessableToken::Null(), GetAudioFocusedSession());
  EXPECT_EQ(1, GetTransientCount());
  EXPECT_NE(mojom::MediaSessionInfo::SessionState::kSuspended,
            GetState(&media_session));
}

TEST_P(AudioFocusManagerTest, RequestAudioFocusTransientMayDuck_FromGain) {
  test::MockMediaSession media_session;

  AudioFocusManager::RequestId request_id =
      RequestAudioFocus(&media_session, mojom::AudioFocusType::kGain);

  EXPECT_EQ(request_id, GetAudioFocusedSession());
  EXPECT_EQ(0, GetTransientMaybeDuckCount());

  RequestAudioFocus(&media_session,
                    mojom::AudioFocusType::kGainTransientMayDuck);
  EXPECT_EQ(base::UnguessableToken::Null(), GetAudioFocusedSession());
  EXPECT_EQ(1, GetTransientMaybeDuckCount());
  EXPECT_NE(mojom::MediaSessionInfo::SessionState::kDucking,
            GetState(&media_session));
}

TEST_P(AudioFocusManagerTest, RequestAudioFocusTransient_FromGainWhileDucking) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(0, GetTransientMaybeDuckCount());
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));

  RequestAudioFocus(&media_session_2,
                    mojom::AudioFocusType::kGainTransientMayDuck);
  EXPECT_EQ(0, GetTransientCount());
  EXPECT_EQ(1, GetTransientMaybeDuckCount());
  EXPECT_EQ(GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking),
            GetState(&media_session_1));

  RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGainTransient);
  EXPECT_EQ(1, GetTransientCount());
  EXPECT_EQ(1, GetTransientMaybeDuckCount());
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));
}

TEST_P(AudioFocusManagerTest,
       RequestAudioFocusTransientMayDuck_FromGainWhileDucking) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(0, GetTransientMaybeDuckCount());
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));

  RequestAudioFocus(&media_session_2,
                    mojom::AudioFocusType::kGainTransientMayDuck);
  EXPECT_EQ(1, GetTransientMaybeDuckCount());
  EXPECT_EQ(GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking),
            GetState(&media_session_1));

  RequestAudioFocus(&media_session_1,
                    mojom::AudioFocusType::kGainTransientMayDuck);
  EXPECT_EQ(2, GetTransientMaybeDuckCount());
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));
}

TEST_P(AudioFocusManagerTest, AbandonAudioFocus_RemovesFocusedEntry) {
  test::MockMediaSession media_session;

  AudioFocusManager::RequestId request_id =
      RequestAudioFocus(&media_session, mojom::AudioFocusType::kGain);
  EXPECT_EQ(request_id, GetAudioFocusedSession());

  media_session.AbandonAudioFocusFromClient();
  EXPECT_EQ(base::UnguessableToken::Null(), GetAudioFocusedSession());
}

TEST_P(AudioFocusManagerTest, AbandonAudioFocus_MultipleCalls) {
  test::MockMediaSession media_session;

  AudioFocusManager::RequestId request_id =
      RequestAudioFocus(&media_session, mojom::AudioFocusType::kGain);
  EXPECT_EQ(request_id, GetAudioFocusedSession());

  AbandonAudioFocusNoReset(&media_session);

  std::unique_ptr<test::TestAudioFocusObserver> observer = CreateObserver();
  media_session.AbandonAudioFocusFromClient();

  EXPECT_EQ(base::UnguessableToken::Null(), GetAudioFocusedSession());
  EXPECT_TRUE(observer->focus_lost_session().is_null());
}

TEST_P(AudioFocusManagerTest, AbandonAudioFocus_RemovesTransientMayDuckEntry) {
  test::MockMediaSession media_session;

  RequestAudioFocus(&media_session,
                    mojom::AudioFocusType::kGainTransientMayDuck);
  EXPECT_EQ(1, GetTransientMaybeDuckCount());

  {
    std::unique_ptr<test::TestAudioFocusObserver> observer = CreateObserver();
    media_session.AbandonAudioFocusFromClient();

    EXPECT_EQ(0, GetTransientMaybeDuckCount());
    EXPECT_TRUE(observer->focus_lost_session()->session_info.Equals(
        test::GetMediaSessionInfoSync(&media_session)));
  }
}

TEST_P(AudioFocusManagerTest, AbandonAudioFocus_RemovesTransientEntry) {
  test::MockMediaSession media_session;

  RequestAudioFocus(&media_session, mojom::AudioFocusType::kGainTransient);
  EXPECT_EQ(1, GetTransientCount());

  {
    std::unique_ptr<test::TestAudioFocusObserver> observer = CreateObserver();
    media_session.AbandonAudioFocusFromClient();

    EXPECT_EQ(0, GetTransientCount());
    EXPECT_TRUE(observer->focus_lost_session()->session_info.Equals(
        test::GetMediaSessionInfoSync(&media_session)));
  }
}

TEST_P(AudioFocusManagerTest, AbandonAudioFocus_WhileDuckingThenResume) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(0, GetTransientMaybeDuckCount());
  EXPECT_NE(mojom::MediaSessionInfo::SessionState::kDucking,
            GetState(&media_session_1));

  RequestAudioFocus(&media_session_2,
                    mojom::AudioFocusType::kGainTransientMayDuck);
  EXPECT_EQ(1, GetTransientMaybeDuckCount());
  EXPECT_EQ(GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking),
            GetState(&media_session_1));

  media_session_1.AbandonAudioFocusFromClient();
  EXPECT_EQ(1, GetTransientMaybeDuckCount());

  media_session_2.AbandonAudioFocusFromClient();
  EXPECT_EQ(0, GetTransientMaybeDuckCount());

  RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_NE(mojom::MediaSessionInfo::SessionState::kDucking,
            GetState(&media_session_1));
}

TEST_P(AudioFocusManagerTest, AbandonAudioFocus_StopsDucking) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(0, GetTransientMaybeDuckCount());
  EXPECT_NE(mojom::MediaSessionInfo::SessionState::kDucking,
            GetState(&media_session_1));

  RequestAudioFocus(&media_session_2,
                    mojom::AudioFocusType::kGainTransientMayDuck);
  EXPECT_EQ(1, GetTransientMaybeDuckCount());
  EXPECT_EQ(GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking),
            GetState(&media_session_1));

  media_session_2.AbandonAudioFocusFromClient();
  EXPECT_EQ(0, GetTransientMaybeDuckCount());
  EXPECT_NE(mojom::MediaSessionInfo::SessionState::kDucking,
            GetState(&media_session_1));
}

TEST_P(AudioFocusManagerTest, AbandonAudioFocus_ResumesPlayback) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(0, GetTransientCount());
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));

  RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGainTransient);
  EXPECT_EQ(1, GetTransientCount());
  EXPECT_EQ(
      GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended),
      GetState(&media_session_1));

  media_session_2.AbandonAudioFocusFromClient();
  EXPECT_EQ(0, GetTransientCount());
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));
}

TEST_P(AudioFocusManagerTest, DuckWhilePlaying) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_NE(mojom::MediaSessionInfo::SessionState::kDucking,
            GetState(&media_session_1));

  RequestAudioFocus(&media_session_2,
                    mojom::AudioFocusType::kGainTransientMayDuck);
  EXPECT_EQ(GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking),
            GetState(&media_session_1));
}

TEST_P(AudioFocusManagerTest, GainSuspendsTransient) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGainTransient);

  RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(
      GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended),
      GetState(&media_session_2));
}

TEST_P(AudioFocusManagerTest, GainSuspendsTransientMayDuck) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  RequestAudioFocus(&media_session_2,
                    mojom::AudioFocusType::kGainTransientMayDuck);

  RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(
      GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended),
      GetState(&media_session_2));
}

TEST_P(AudioFocusManagerTest, DuckWithMultipleTransientMayDucks) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;
  test::MockMediaSession media_session_3;
  test::MockMediaSession media_session_4;

  RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_NE(mojom::MediaSessionInfo::SessionState::kDucking,
            GetState(&media_session_1));

  RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGainTransient);
  EXPECT_NE(mojom::MediaSessionInfo::SessionState::kDucking,
            GetState(&media_session_2));

  RequestAudioFocus(&media_session_3,
                    mojom::AudioFocusType::kGainTransientMayDuck);
  EXPECT_EQ(GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking),
            GetState(&media_session_1));
  EXPECT_EQ(GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking),
            GetState(&media_session_2));

  RequestAudioFocus(&media_session_4,
                    mojom::AudioFocusType::kGainTransientMayDuck);
  EXPECT_EQ(GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking),
            GetState(&media_session_1));
  EXPECT_EQ(GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking),
            GetState(&media_session_2));

  media_session_3.AbandonAudioFocusFromClient();
  EXPECT_EQ(GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking),
            GetState(&media_session_1));
  EXPECT_EQ(GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking),
            GetState(&media_session_2));

  media_session_4.AbandonAudioFocusFromClient();
  EXPECT_NE(mojom::MediaSessionInfo::SessionState::kDucking,
            GetState(&media_session_1));
  EXPECT_NE(mojom::MediaSessionInfo::SessionState::kDucking,
            GetState(&media_session_2));
}

TEST_P(AudioFocusManagerTest, MediaSessionDestroyed_ReleasesFocus) {
  {
    test::MockMediaSession media_session;

    AudioFocusManager::RequestId request_id =
        RequestAudioFocus(&media_session, mojom::AudioFocusType::kGain);
    EXPECT_EQ(request_id, GetAudioFocusedSession());
  }

  // If the media session is destroyed without abandoning audio focus we do not
  // know until we next interact with the manager.
  test::MockMediaSession media_session;
  RequestAudioFocus(&media_session,
                    mojom::AudioFocusType::kGainTransientMayDuck);
  EXPECT_EQ(base::UnguessableToken::Null(), GetAudioFocusedSession());
}

TEST_P(AudioFocusManagerTest, MediaSessionDestroyed_ReleasesTransient) {
  {
    test::MockMediaSession media_session;
    RequestAudioFocus(&media_session, mojom::AudioFocusType::kGainTransient);
    EXPECT_EQ(1, GetTransientCount());
  }

  // If the media session is destroyed without abandoning audio focus we do not
  // know until we next interact with the manager.
  test::MockMediaSession media_session;
  RequestAudioFocus(&media_session, mojom::AudioFocusType::kGain);
  EXPECT_EQ(0, GetTransientCount());
}

TEST_P(AudioFocusManagerTest, MediaSessionDestroyed_ReleasesTransientMayDucks) {
  {
    test::MockMediaSession media_session;
    RequestAudioFocus(&media_session,
                      mojom::AudioFocusType::kGainTransientMayDuck);
    EXPECT_EQ(1, GetTransientMaybeDuckCount());
  }

  // If the media session is destroyed without abandoning audio focus we do not
  // know until we next interact with the manager.
  test::MockMediaSession media_session;
  RequestAudioFocus(&media_session, mojom::AudioFocusType::kGain);
  EXPECT_EQ(0, GetTransientMaybeDuckCount());
}

TEST_P(AudioFocusManagerTest, GainDucksForceDuck) {
  test::MockMediaSession media_session_1(true /* force_duck */);
  test::MockMediaSession media_session_2;

  RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);

  AudioFocusManager::RequestId request_id_2 =
      RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGain);

  EXPECT_EQ(request_id_2, GetAudioFocusedSession());
  EXPECT_EQ(GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking),
            GetState(&media_session_1));
}

TEST_P(AudioFocusManagerTest, ForceDuckSessionShouldAlwaysBeDuckedFromGain) {
  test::MockMediaSession media_session_1(true /* force_duck */);
  test::MockMediaSession media_session_2;
  test::MockMediaSession media_session_3;

  AudioFocusManager::RequestId request_id_1 =
      RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  AudioFocusManager::RequestId request_id_2 =
      RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGain);

  AudioFocusManager::RequestId request_id_3 =
      RequestAudioFocus(&media_session_3, mojom::AudioFocusType::kGain);
  EXPECT_EQ(request_id_3, GetAudioFocusedSession());

  EXPECT_EQ(
      GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended),
      GetState(&media_session_2));
  EXPECT_EQ(GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking),
            GetState(&media_session_1));

  media_session_3.AbandonAudioFocusFromClient();
  EXPECT_EQ(request_id_2, GetAudioFocusedSession());
  EXPECT_EQ(GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking),
            GetState(&media_session_1));

  media_session_2.AbandonAudioFocusFromClient();
  EXPECT_EQ(request_id_1, GetAudioFocusedSession());
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));
}

TEST_P(AudioFocusManagerTest,
       ForceDuckSessionShouldAlwaysBeDuckedFromTransient) {
  test::MockMediaSession media_session_1(true /* force_duck */);
  test::MockMediaSession media_session_2;

  AudioFocusManager::RequestId request_id_1 =
      RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGainTransient);

  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_2));
  EXPECT_EQ(GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking),
            GetState(&media_session_1));

  media_session_2.AbandonAudioFocusFromClient();
  EXPECT_EQ(request_id_1, GetAudioFocusedSession());
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));
}

TEST_P(AudioFocusManagerTest, AudioFocusObserver_RequestNoop) {
  test::MockMediaSession media_session;
  AudioFocusManager::RequestId request_id;

  {
    std::unique_ptr<test::TestAudioFocusObserver> observer = CreateObserver();
    request_id =
        RequestAudioFocus(&media_session, mojom::AudioFocusType::kGain);

    EXPECT_EQ(request_id, GetAudioFocusedSession());
    EXPECT_EQ(mojom::AudioFocusType::kGain,
              observer->focus_gained_session()->audio_focus_type);
  }

  {
    std::unique_ptr<test::TestAudioFocusObserver> observer = CreateObserver();
    RequestAudioFocus(&media_session, mojom::AudioFocusType::kGain);

    EXPECT_EQ(request_id, GetAudioFocusedSession());
    EXPECT_TRUE(observer->focus_gained_session().is_null());
  }
}

TEST_P(AudioFocusManagerTest, AudioFocusObserver_TransientMayDuck) {
  test::MockMediaSession media_session;

  {
    std::unique_ptr<test::TestAudioFocusObserver> observer = CreateObserver();
    RequestAudioFocus(&media_session,
                      mojom::AudioFocusType::kGainTransientMayDuck);

    EXPECT_EQ(1, GetTransientMaybeDuckCount());
    EXPECT_EQ(mojom::AudioFocusType::kGainTransientMayDuck,
              observer->focus_gained_session()->audio_focus_type);
  }

  {
    std::unique_ptr<test::TestAudioFocusObserver> observer = CreateObserver();
    media_session.AbandonAudioFocusFromClient();

    EXPECT_EQ(0, GetTransientMaybeDuckCount());
    EXPECT_TRUE(observer->focus_lost_session()->session_info.Equals(
        test::GetMediaSessionInfoSync(&media_session)));
  }
}

TEST_P(AudioFocusManagerTest, GetDebugInfo) {
  test::MockMediaSession media_session;
  AudioFocusManager::RequestId request_id =
      RequestAudioFocus(&media_session, mojom::AudioFocusType::kGain);

  mojom::MediaSessionDebugInfoPtr debug_info = GetDebugInfo(request_id);
  EXPECT_FALSE(debug_info->name.empty());
  EXPECT_FALSE(debug_info->owner.empty());
  EXPECT_FALSE(debug_info->state.empty());
}

TEST_P(AudioFocusManagerTest, GetDebugInfo_BadRequestId) {
  mojom::MediaSessionDebugInfoPtr debug_info =
      GetDebugInfo(base::UnguessableToken::Create());
  EXPECT_TRUE(debug_info->name.empty());
}

TEST_P(AudioFocusManagerTest,
       RequestAudioFocusTransient_FromGainWhileSuspended) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(0, GetTransientCount());
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));

  RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGainTransient);
  EXPECT_EQ(1, GetTransientCount());
  EXPECT_EQ(
      GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended),
      GetState(&media_session_1));

  RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGainTransient);
  EXPECT_EQ(2, GetTransientCount());
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));
}

TEST_P(AudioFocusManagerTest,
       RequestAudioFocusTransientMayDuck_FromGainWhileSuspended) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(0, GetTransientCount());
  EXPECT_EQ(0, GetTransientMaybeDuckCount());
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));

  RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGainTransient);
  EXPECT_EQ(1, GetTransientCount());
  EXPECT_EQ(0, GetTransientMaybeDuckCount());
  EXPECT_EQ(
      GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended),
      GetState(&media_session_1));

  RequestAudioFocus(&media_session_1,
                    mojom::AudioFocusType::kGainTransientMayDuck);
  EXPECT_EQ(1, GetTransientCount());
  EXPECT_EQ(1, GetTransientMaybeDuckCount());
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));
}

TEST_P(AudioFocusManagerTest, Source_AssociatedWithBinding) {
  base::UnguessableToken identity = base::UnguessableToken::Create();
  SetSource(identity, kExampleSourceName);

  base::UnguessableToken new_identity = base::UnguessableToken::Create();
  mojo::Remote<mojom::AudioFocusManager> new_ptr =
      CreateAudioFocusManagerRemote();
  new_ptr->SetSource(new_identity, kExampleSourceName2);
  new_ptr.FlushForTesting();

  test::MockMediaSession media_session_1;
  RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(kExampleSourceName, GetSourceNameForLastRequest());
  EXPECT_EQ(identity, GetIdentityForLastRequest());

  test::MockMediaSession media_session_2;
  media_session_2.RequestAudioFocusFromService(new_ptr,
                                               mojom::AudioFocusType::kGain);
  EXPECT_EQ(kExampleSourceName2, GetSourceNameForLastRequest());
  EXPECT_EQ(new_identity, GetIdentityForLastRequest());
}

TEST_P(AudioFocusManagerTest, Source_Empty) {
  test::MockMediaSession media_session;
  RequestAudioFocus(&media_session, mojom::AudioFocusType::kGain);
  EXPECT_TRUE(GetSourceNameForLastRequest().empty());
  EXPECT_EQ(base::UnguessableToken::Null(), GetIdentityForLastRequest());
}

TEST_P(AudioFocusManagerTest, Source_Updated) {
  base::UnguessableToken identity = base::UnguessableToken::Create();
  SetSource(identity, kExampleSourceName);

  test::MockMediaSession media_session;
  RequestAudioFocus(&media_session, mojom::AudioFocusType::kGain);
  EXPECT_EQ(kExampleSourceName, GetSourceNameForLastRequest());
  EXPECT_EQ(identity, GetIdentityForLastRequest());

  base::UnguessableToken new_identity = base::UnguessableToken::Create();
  SetSource(new_identity, kExampleSourceName2);
  EXPECT_EQ(kExampleSourceName, GetSourceNameForLastRequest());
  EXPECT_EQ(identity, GetIdentityForLastRequest());
}

TEST_P(AudioFocusManagerTest,
       AbandonAudioFocus_ObserverFocusGain_NoTopSession) {
  test::MockMediaSession media_session;

  RequestAudioFocus(&media_session,
                    mojom::AudioFocusType::kGainTransientMayDuck);
  EXPECT_EQ(1, GetTransientMaybeDuckCount());
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session));

  {
    std::unique_ptr<test::TestAudioFocusObserver> observer = CreateObserver();
    media_session.AbandonAudioFocusFromClient();

    EXPECT_EQ(0, GetTransientMaybeDuckCount());
    EXPECT_TRUE(observer->focus_lost_session()->session_info.Equals(
        test::GetMediaSessionInfoSync(&media_session)));
    EXPECT_TRUE(observer->focus_gained_session().is_null());

    auto notifications = observer->notifications();
    EXPECT_EQ(1u, notifications.size());
    EXPECT_EQ(test::TestAudioFocusObserver::NotificationType::kFocusLost,
              notifications[0]);
  }
}

TEST_P(AudioFocusManagerTest,
       AbandonAudioFocus_ObserverFocusGain_NewTopSession) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(0, GetTransientMaybeDuckCount());
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));

  RequestAudioFocus(&media_session_2,
                    mojom::AudioFocusType::kGainTransientMayDuck);
  EXPECT_EQ(1, GetTransientMaybeDuckCount());
  EXPECT_EQ(GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking),
            GetState(&media_session_1));

  mojom::MediaSessionInfoPtr media_session_1_info =
      test::GetMediaSessionInfoSync(&media_session_1);

  {
    std::unique_ptr<test::TestAudioFocusObserver> observer = CreateObserver();
    media_session_2.AbandonAudioFocusFromClient();

    EXPECT_EQ(0, GetTransientMaybeDuckCount());
    EXPECT_TRUE(observer->focus_lost_session()->session_info.Equals(
        test::GetMediaSessionInfoSync(&media_session_2)));
    EXPECT_TRUE(observer->focus_gained_session()->session_info.Equals(
        media_session_1_info));

    // FocusLost should always come before FocusGained so observers always know
    // the current session that has focus.
    auto notifications = observer->notifications();
    EXPECT_EQ(2u, notifications.size());
    EXPECT_EQ(test::TestAudioFocusObserver::NotificationType::kFocusLost,
              notifications[0]);
    EXPECT_EQ(test::TestAudioFocusObserver::NotificationType::kFocusGained,
              notifications[1]);
  }
}

TEST_P(AudioFocusManagerTest, AudioFocusGrouping_LayeredFocus) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;
  test::MockMediaSession media_session_3;

  base::UnguessableToken group_id = base::UnguessableToken::Create();

  ASSERT_TRUE(RequestGroupedAudioFocus(base::UnguessableToken::Create(),
                                       &media_session_1,
                                       mojom::AudioFocusType::kGain, group_id));
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));

  RequestAudioFocus(&media_session_2,
                    mojom::AudioFocusType::kGainTransientMayDuck);
  EXPECT_EQ(GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking),
            GetState(&media_session_1));

  // When we request audio focus for media_session_3 the group will take audio
  // focus and we suspend the ducking session.
  ASSERT_TRUE(RequestGroupedAudioFocus(
      base::UnguessableToken::Create(), &media_session_3,
      mojom::AudioFocusType::kGainTransient, group_id));
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_3));

  EXPECT_EQ(
      GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended),
      GetState(&media_session_2));
  EXPECT_EQ(GetStateFromParam(
                IsGroupingEnabled()
                    ? mojom::MediaSessionInfo::SessionState::kActive
                    : mojom::MediaSessionInfo::SessionState::kSuspended),
            GetState(&media_session_1));
}

TEST_P(AudioFocusManagerTest, AudioFocusGrouping_TransientResume) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;
  test::MockMediaSession media_session_3;
  test::MockMediaSession media_session_4;

  base::UnguessableToken group_id = base::UnguessableToken::Create();

  ASSERT_TRUE(RequestGroupedAudioFocus(base::UnguessableToken::Create(),
                                       &media_session_1,
                                       mojom::AudioFocusType::kGain, group_id));
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));

  RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGain);
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_2));

  ASSERT_TRUE(RequestGroupedAudioFocus(base::UnguessableToken::Create(),
                                       &media_session_3,
                                       mojom::AudioFocusType::kGain, group_id));
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_3));

  RequestAudioFocus(&media_session_4, mojom::AudioFocusType::kGainTransient);
  EXPECT_EQ(
      GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended),
      GetState(&media_session_1));
  EXPECT_EQ(
      GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended),
      GetState(&media_session_2));
  EXPECT_EQ(
      GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended),
      GetState(&media_session_3));

  media_session_4.AbandonAudioFocusFromClient();

  // TODO(crbug.com/40606983): This should wait on a more precise
  // condition than RunLoop idling, but it's not clear exactly what that
  // should be.
  base::RunLoop().RunUntilIdle();

  EXPECT_EQ(IsGroupingEnabled()
                ? mojom::MediaSessionInfo::SessionState::kActive
                : mojom::MediaSessionInfo::SessionState::kSuspended,
            GetState(&media_session_1));
  EXPECT_EQ(
      GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended),
      GetState(&media_session_2));
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_3));
}

TEST_P(AudioFocusManagerTest, AudioFocusGrouping_DoNotSuspendSameGroup) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  base::UnguessableToken group_id = base::UnguessableToken::Create();

  ASSERT_TRUE(RequestGroupedAudioFocus(base::UnguessableToken::Create(),
                                       &media_session_1,
                                       mojom::AudioFocusType::kGain, group_id));
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));

  ASSERT_TRUE(RequestGroupedAudioFocus(base::UnguessableToken::Create(),
                                       &media_session_2,
                                       mojom::AudioFocusType::kGain, group_id));
  EXPECT_EQ(IsGroupingEnabled()
                ? mojom::MediaSessionInfo::SessionState::kActive
                : mojom::MediaSessionInfo::SessionState::kSuspended,
            GetState(&media_session_1));
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_2));
}

TEST_P(AudioFocusManagerTest, AudioFocusGrouping_DuckSameGroup) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  base::UnguessableToken group_id = base::UnguessableToken::Create();

  ASSERT_TRUE(RequestGroupedAudioFocus(base::UnguessableToken::Create(),
                                       &media_session_1,
                                       mojom::AudioFocusType::kGain, group_id));
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));

  ASSERT_TRUE(RequestGroupedAudioFocus(
      base::UnguessableToken::Create(), &media_session_2,
      mojom::AudioFocusType::kGainTransientMayDuck, group_id));
  EXPECT_EQ(GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking),
            GetState(&media_session_1));
}

TEST_P(AudioFocusManagerTest, AudioFocusGrouping_TransientSameGroup) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  base::UnguessableToken group_id = base::UnguessableToken::Create();

  ASSERT_TRUE(RequestGroupedAudioFocus(base::UnguessableToken::Create(),
                                       &media_session_1,
                                       mojom::AudioFocusType::kGain, group_id));
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));

  ASSERT_TRUE(RequestGroupedAudioFocus(
      base::UnguessableToken::Create(), &media_session_2,
      mojom::AudioFocusType::kGainTransient, group_id));
  EXPECT_EQ(IsGroupingEnabled()
                ? mojom::MediaSessionInfo::SessionState::kActive
                : mojom::MediaSessionInfo::SessionState::kSuspended,
            GetState(&media_session_1));
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_2));
}

TEST_P(AudioFocusManagerTest, RequestAudioFocus_PreferStop_LossToGain) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  media_session_1.SetPreferStop(true);

  AudioFocusManager::RequestId request_id_1 =
      RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(request_id_1, GetAudioFocusedSession());
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));

  AudioFocusManager::RequestId request_id_2 =
      RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGain);
  EXPECT_EQ(request_id_2, GetAudioFocusedSession());
  EXPECT_EQ(GetStateFromParam(mojom::MediaSessionInfo::SessionState::kInactive),
            GetState(&media_session_1));
}

TEST_P(AudioFocusManagerTest,
       RequestAudioFocus_PreferStop_LossToGainTransient) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  media_session_1.SetPreferStop(true);

  AudioFocusManager::RequestId request_id_1 =
      RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(request_id_1, GetAudioFocusedSession());
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));

  RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGainTransient);
  EXPECT_EQ(
      GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended),
      GetState(&media_session_1));
}

TEST_P(AudioFocusManagerTest, GainFocusTypeHasEffectEvenIfSuspended) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;
  test::MockMediaSession media_session_3;

  AudioFocusManager::RequestId request_id_1 =
      RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(request_id_1, GetAudioFocusedSession());

  RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGain);
  EXPECT_EQ(
      GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended),
      GetState(&media_session_1));

  // When the second session becomes suspended and that event originated from
  // the session itself then we should keep the other session suspended.
  media_session_2.Suspend(mojom::MediaSession::SuspendType::kUI);
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kSuspended,
            GetState(&media_session_2));

  {
    test::MockMediaSessionMojoObserver observer(media_session_1);
    observer.WaitForState(
        GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended));
  }

  // When the second session is resumed then we should still keep the other
  // session suspended.
  media_session_2.Resume(mojom::MediaSession::SuspendType::kUI);
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_2));

  {
    test::MockMediaSessionMojoObserver observer(media_session_1);
    observer.WaitForState(
        GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended));
  }

  // If a new session takes focus then this should suspend all sessions.
  RequestAudioFocus(&media_session_3, mojom::AudioFocusType::kGainTransient);

  {
    test::MockMediaSessionMojoObserver observer(media_session_2);
    observer.WaitForState(
        GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended));
  }

  {
    test::MockMediaSessionMojoObserver observer(media_session_1);
    observer.WaitForState(
        GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended));
  }

  // If the second session regains focus then it should suspend all sessions.
  RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGain);
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_2));

  {
    test::MockMediaSessionMojoObserver observer(media_session_1);
    observer.WaitForState(
        GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended));
  }

  {
    test::MockMediaSessionMojoObserver observer(media_session_3);
    observer.WaitForState(
        GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended));
  }
}

TEST_P(AudioFocusManagerTest, TransientFocusTypeHasNoEffectIfSuspended) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;
  test::MockMediaSession media_session_3;

  AudioFocusManager::RequestId request_id_1 =
      RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(request_id_1, GetAudioFocusedSession());

  RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGainTransient);
  EXPECT_EQ(
      GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended),
      GetState(&media_session_1));

  // When the transient session becomes suspended and that event originates from
  // the session itself then we should stop pausing the other session.
  media_session_2.Suspend(mojom::MediaSession::SuspendType::kUI);
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kSuspended,
            GetState(&media_session_2));

  {
    test::MockMediaSessionMojoObserver observer(media_session_1);
    observer.WaitForState(mojom::MediaSessionInfo::SessionState::kActive);
  }

  // When the transient session is resumed then we should pause the other
  // session again.
  media_session_2.Resume(mojom::MediaSession::SuspendType::kUI);
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_2));

  {
    test::MockMediaSessionMojoObserver observer(media_session_1);
    observer.WaitForState(
        GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended));
  }

  // If we have a new session take focus then this should suspend all the other
  // sessions and the transient session should have no effect.
  RequestAudioFocus(&media_session_3, mojom::AudioFocusType::kGainTransient);

  {
    test::MockMediaSessionMojoObserver observer(media_session_2);
    observer.WaitForState(
        GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended));
  }

  {
    test::MockMediaSessionMojoObserver observer(media_session_1);
    observer.WaitForState(
        GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended));
  }

  // If the second session regains focus then it should start pausing again.
  RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGainTransient);
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_2));

  {
    test::MockMediaSessionMojoObserver observer(media_session_1);
    observer.WaitForState(
        GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended));
  }

  {
    test::MockMediaSessionMojoObserver observer(media_session_3);
    observer.WaitForState(
        GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended));
  }
}

TEST_P(AudioFocusManagerTest, TransientDuckFocusTypeHasNoEffectIfSuspended) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;
  test::MockMediaSession media_session_3;

  AudioFocusManager::RequestId request_id_1 =
      RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(request_id_1, GetAudioFocusedSession());

  RequestAudioFocus(&media_session_2,
                    mojom::AudioFocusType::kGainTransientMayDuck);
  EXPECT_EQ(GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking),
            GetState(&media_session_1));

  // When the ducking session becomes suspended and that event originates from
  // the session itself then we should stop ducking.
  media_session_2.Suspend(mojom::MediaSession::SuspendType::kUI);
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kSuspended,
            GetState(&media_session_2));

  {
    test::MockMediaSessionMojoObserver observer(media_session_1);
    observer.WaitForState(mojom::MediaSessionInfo::SessionState::kActive);
  }

  // When the ducking session is resumed then we should resume ducking.
  media_session_2.Resume(mojom::MediaSession::SuspendType::kUI);
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_2));

  {
    test::MockMediaSessionMojoObserver observer(media_session_1);
    observer.WaitForState(
        GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking));
  }

  // If we have a new session take focus then this should suspend all the other
  // sessions and we should not have any ducking from the ducking session (since
  // it is suspended).
  RequestAudioFocus(&media_session_3, mojom::AudioFocusType::kGainTransient);

  {
    test::MockMediaSessionMojoObserver observer(media_session_2);
    observer.WaitForState(
        GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended));
  }

  {
    test::MockMediaSessionMojoObserver observer(media_session_1);
    observer.WaitForState(
        GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended));
  }

  // If the ducking session regains focus then it should start ducking again.
  RequestAudioFocus(&media_session_2,
                    mojom::AudioFocusType::kGainTransientMayDuck);
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_2));

  {
    test::MockMediaSessionMojoObserver observer(media_session_1);
    observer.WaitForState(
        GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking));
  }

  {
    test::MockMediaSessionMojoObserver observer(media_session_3);
    observer.WaitForState(
        GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking));
  }
}

TEST_P(AudioFocusManagerTest, AmbientFocusHasNoEffect) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  AudioFocusManager::RequestId request_id_1 =
      RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(request_id_1, GetAudioFocusedSession());
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));

  EXPECT_EQ(0, GetAmbientCount());
  RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kAmbient);

  EXPECT_EQ(1, GetAmbientCount());
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_2));

  media_session_2.AbandonAudioFocusFromClient();

  EXPECT_EQ(0, GetAmbientCount());
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));
}

TEST_P(AudioFocusManagerTest, AudioFocusObserver_NotTopMost) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  AudioFocusManager::RequestId request_id_1 =
      RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(request_id_1, GetAudioFocusedSession());
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));

  RequestAudioFocus(&media_session_2,
                    mojom::AudioFocusType::kGainTransientMayDuck);
  EXPECT_EQ(GetStateFromParam(mojom::MediaSessionInfo::SessionState::kDucking),
            GetState(&media_session_1));
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_2));

  {
    std::unique_ptr<test::TestAudioFocusObserver> observer = CreateObserver();
    media_session_1.AbandonAudioFocusFromClient();

    EXPECT_TRUE(observer->focus_lost_session()->session_info.Equals(
        test::GetMediaSessionInfoSync(&media_session_1)));
  }
}

TEST_P(AudioFocusManagerTest, SuspendAllSessionOnPowerSuspend) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  {
    test::MockMediaSessionMojoObserver observer(media_session_1);
    RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
    observer.WaitForState(mojom::MediaSessionInfo::SessionState::kActive);
  }

  {
    test::MockMediaSessionMojoObserver observer(media_session_2);
    RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGain);
    observer.WaitForState(mojom::MediaSessionInfo::SessionState::kActive);
  }

  test::MockMediaSessionMojoObserver observer_1(media_session_1);
  test::MockMediaSessionMojoObserver observer_2(media_session_2);

  GenerateSuspendEvent();

  observer_1.WaitForState(mojom::MediaSessionInfo::SessionState::kSuspended);
  observer_2.WaitForState(mojom::MediaSessionInfo::SessionState::kSuspended);
}

TEST_P(AudioFocusManagerTest, TransientPauseShouldDelayControllerPause) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));

  RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGainTransient);
  EXPECT_EQ(
      GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended),
      GetState(&media_session_1));

  mojo::Remote<mojom::MediaController> controller;
  controller_manager()->CreateMediaControllerForSession(
      controller.BindNewPipeAndPassReceiver(), media_session_1.request_id());
  controller_manager().FlushForTesting();

  controller->Suspend();
  controller.FlushForTesting();
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kSuspended,
            GetState(&media_session_1));

  // When we abandon the transient session then we will apply the last
  // controller action.
  media_session_2.AbandonAudioFocusFromClient();
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kSuspended,
            GetState(&media_session_1));
}

TEST_P(AudioFocusManagerTest, TransientPauseShouldDelayControllerStop) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));

  RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGainTransient);
  EXPECT_EQ(
      GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended),
      GetState(&media_session_1));

  mojo::Remote<mojom::MediaController> controller;
  controller_manager()->CreateMediaControllerForSession(
      controller.BindNewPipeAndPassReceiver(), media_session_1.request_id());
  controller_manager().FlushForTesting();

  controller->Stop();
  controller.FlushForTesting();

  // If enforcement is enabled then the session was previously suspended by the
  // transient session and therefore we should be suspended. Otherwise, we
  // should be inactive because the stop command would not have been delayed.
  EXPECT_EQ(IsEnforcementEnabled()
                ? mojom::MediaSessionInfo::SessionState::kSuspended
                : mojom::MediaSessionInfo::SessionState::kInactive,
            GetState(&media_session_1));

  {
    // When we abandon the transient session then we will apply the last
    // controller action.
    test::MockMediaSessionMojoObserver observer(media_session_1);
    media_session_2.AbandonAudioFocusFromClient();
    observer.WaitForState(mojom::MediaSessionInfo::SessionState::kInactive);
  }
}

TEST_P(AudioFocusManagerTest, TransientPauseShouldDelayControllerResume) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));

  mojo::Remote<mojom::MediaController> controller;
  controller_manager()->CreateMediaControllerForSession(
      controller.BindNewPipeAndPassReceiver(), media_session_1.request_id());
  controller_manager().FlushForTesting();

  controller->Suspend();
  controller.FlushForTesting();
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kSuspended,
            GetState(&media_session_1));

  RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGainTransient);
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kSuspended,
            GetState(&media_session_1));

  controller->Resume();
  controller.FlushForTesting();

  // If enforcement is enabled then the session was previously suspended by the
  // transient session and therefore we should be suspended. Otherwise, we
  // should be active because the resume command would not have been delayed.
  EXPECT_EQ(
      GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended),
      GetState(&media_session_1));

  {
    // When we abandon the transient session then we will apply the last
    // controller action.
    test::MockMediaSessionMojoObserver observer(media_session_1);
    media_session_2.AbandonAudioFocusFromClient();
    observer.WaitForState(mojom::MediaSessionInfo::SessionState::kActive);
  }
}

TEST_P(AudioFocusManagerTest, TransientPauseShouldDelayLastActionOnly) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_1));

  RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGainTransient);
  EXPECT_EQ(
      GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended),
      GetState(&media_session_1));

  mojo::Remote<mojom::MediaController> controller;
  controller_manager()->CreateMediaControllerForSession(
      controller.BindNewPipeAndPassReceiver(), media_session_1.request_id());
  controller_manager().FlushForTesting();

  controller->Resume();
  controller.FlushForTesting();

  // The resume action should be delayed because we were suspended by the
  // transient session.
  EXPECT_EQ(
      GetStateFromParam(mojom::MediaSessionInfo::SessionState::kSuspended),
      GetState(&media_session_1));

  // Calling suspend while we are still suspended should cancel the delayed
  // resume action so we will never resume.
  controller->Suspend();
  controller.FlushForTesting();
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kSuspended,
            GetState(&media_session_1));

  // When we abandon the transient session then we will apply the last
  // controller action.
  media_session_2.AbandonAudioFocusFromClient();
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kSuspended,
            GetState(&media_session_1));
}

TEST_P(AudioFocusManagerTest, RequestIdValidation) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  base::UnguessableToken request_id = base::UnguessableToken::Create();

  EXPECT_TRUE(RequestGroupedAudioFocus(request_id, &media_session_1,
                                       mojom::AudioFocusType::kGain,
                                       base::UnguessableToken::Create()));
  EXPECT_EQ(request_id, GetAudioFocusedSession());

  // The audio focus request should fail since we have already used that id.
  EXPECT_FALSE(RequestGroupedAudioFocus(request_id, &media_session_2,
                                        mojom::AudioFocusType::kGain,
                                        base::UnguessableToken::Create()));

  media_session_1.AbandonAudioFocusFromClient();
  EXPECT_EQ(base::UnguessableToken::Null(), GetAudioFocusedSession());

  // If we abandon focus then we should be able to use the id now.
  EXPECT_TRUE(RequestGroupedAudioFocus(request_id, &media_session_2,
                                       mojom::AudioFocusType::kGain,
                                       base::UnguessableToken::Create()));
  EXPECT_EQ(request_id, GetAudioFocusedSession());
}

TEST_P(AudioFocusManagerTest, SourceObservers) {
  // Create two identity observers for two different identities.
  base::UnguessableToken identity_1 = base::UnguessableToken::Create();
  base::UnguessableToken identity_2 = base::UnguessableToken::Create();
  std::unique_ptr<test::TestAudioFocusObserver> observer_1 =
      CreateSourceObserver(identity_1);
  std::unique_ptr<test::TestAudioFocusObserver> observer_2 =
      CreateSourceObserver(identity_2);

  // Request audio focus for the first identity.
  SetSource(identity_1, kExampleSourceName);
  test::MockMediaSession media_session_1;
  base::UnguessableToken request_id_1 =
      RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);

  // The observer for the first identity should see the gained focus, while the
  // observer for the second identity should see nothing.
  EXPECT_EQ(request_id_1, observer_1->focus_gained_session()->request_id);
  EXPECT_TRUE(observer_2->focus_gained_session().is_null());

  // Request audio focus for the second identity.
  SetSource(identity_2, kExampleSourceName);
  test::MockMediaSession media_session_2;
  base::UnguessableToken request_id_2 =
      RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGain);

  // The observer for the first identity should still show the first request,
  // while the observer for the second identity should see the new session.
  EXPECT_EQ(request_id_1, observer_1->focus_gained_session()->request_id);
  EXPECT_EQ(request_id_2, observer_2->focus_gained_session()->request_id);

  // Make another request in the second identity.
  test::MockMediaSession media_session_3;
  base::UnguessableToken request_id_3 =
      RequestAudioFocus(&media_session_3, mojom::AudioFocusType::kGain);

  // The observer for the first identity should still show the first request,
  // while the observer for the second identity should see the new session.
  EXPECT_EQ(request_id_1, observer_1->focus_gained_session()->request_id);
  EXPECT_EQ(request_id_3, observer_2->focus_gained_session()->request_id);

  // Abandon the topmost session.
  media_session_3.AbandonAudioFocusFromClient();
  FlushForTesting();

  // The observer for the second identity should get the new lost and gained
  // sessions, with no updates to the first observer.
  EXPECT_EQ(request_id_3, observer_2->focus_lost_session()->request_id);
  EXPECT_EQ(request_id_2, observer_2->focus_gained_session()->request_id);
  EXPECT_EQ(request_id_1, observer_1->focus_gained_session()->request_id);
  EXPECT_TRUE(observer_1->focus_lost_session().is_null());
}

TEST_P(AudioFocusManagerTest, GetSourceFocusRequests) {
  // Establish identities.
  base::UnguessableToken identity_1 = base::UnguessableToken::Create();
  base::UnguessableToken identity_2 = base::UnguessableToken::Create();
  base::UnguessableToken identity_3 = base::UnguessableToken::Create();

  // Create a focus request for the first identity.
  SetSource(identity_1, kExampleSourceName);
  test::MockMediaSession media_session_1;
  base::UnguessableToken request_id_1 =
      RequestAudioFocus(&media_session_1, mojom::AudioFocusType::kGain);

  // Create a focus request for the second identity.
  SetSource(identity_2, kExampleSourceName);
  test::MockMediaSession media_session_2;
  base::UnguessableToken request_id_2 =
      RequestAudioFocus(&media_session_2, mojom::AudioFocusType::kGain);

  // Create another focus request for the first identity.
  SetSource(identity_1, kExampleSourceName);
  test::MockMediaSession media_session_3;
  base::UnguessableToken request_id_3 =
      RequestAudioFocus(&media_session_3, mojom::AudioFocusType::kGain);

  // Use the GetSourceFocusRequests API to get requests for each identity.
  std::vector<mojom::AudioFocusRequestStatePtr> identity_1_requests =
      GetSourceFocusRequests(identity_1);
  std::vector<mojom::AudioFocusRequestStatePtr> identity_2_requests =
      GetSourceFocusRequests(identity_2);
  std::vector<mojom::AudioFocusRequestStatePtr> identity_3_requests =
      GetSourceFocusRequests(identity_3);

  // Ensure that the API returned the right requests for the first identity.
  EXPECT_EQ(2u, identity_1_requests.size());
  EXPECT_EQ(request_id_1, identity_1_requests[0]->request_id);
  EXPECT_EQ(request_id_3, identity_1_requests[1]->request_id);

  // Ensure that the API returned the right requests for the second identity.
  EXPECT_EQ(1u, identity_2_requests.size());
  EXPECT_EQ(request_id_2, identity_2_requests[0]->request_id);

  // Ensure that the API returned nothing for the unused identity.
  EXPECT_TRUE(identity_3_requests.empty());
}

TEST_P(AudioFocusManagerTest, StartDuckingAllAudio_NoExemption) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  base::UnguessableToken group_id = base::UnguessableToken::Create();

  // Request audio focus for two media sessions.
  ASSERT_TRUE(RequestGroupedAudioFocus(base::UnguessableToken::Create(),
                                       &media_session_1,
                                       mojom::AudioFocusType::kGain, group_id));
  ASSERT_TRUE(RequestGroupedAudioFocus(base::UnguessableToken::Create(),
                                       &media_session_2,
                                       mojom::AudioFocusType::kGain, group_id));
  EXPECT_EQ(IsGroupingEnabled()
                ? mojom::MediaSessionInfo::SessionState::kActive
                : mojom::MediaSessionInfo::SessionState::kSuspended,
            GetState(&media_session_1));
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_2));

  // A call to `StartDuckingAllAudio()` with no exempted request ID should duck
  // all sessions.
  StartDuckingAllAudio(std::nullopt);
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kDucking,
            GetState(&media_session_1));
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kDucking,
            GetState(&media_session_2));

  // Once ducking all audio is stopped, the sessions should no longer be ducked.
  StopDuckingAllAudio();
  EXPECT_EQ(IsGroupingEnabled()
                ? mojom::MediaSessionInfo::SessionState::kActive
                : mojom::MediaSessionInfo::SessionState::kSuspended,
            GetState(&media_session_1));
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_2));
}

TEST_P(AudioFocusManagerTest, StartDuckingAllAudio_WithExemption) {
  test::MockMediaSession media_session_1;
  test::MockMediaSession media_session_2;

  base::UnguessableToken group_id = base::UnguessableToken::Create();
  base::UnguessableToken id_2 = base::UnguessableToken::Create();

  // Request audio focus for two media sessions.
  ASSERT_TRUE(RequestGroupedAudioFocus(base::UnguessableToken::Create(),
                                       &media_session_1,
                                       mojom::AudioFocusType::kGain, group_id));
  ASSERT_TRUE(RequestGroupedAudioFocus(id_2, &media_session_2,
                                       mojom::AudioFocusType::kGain, group_id));
  EXPECT_EQ(IsGroupingEnabled()
                ? mojom::MediaSessionInfo::SessionState::kActive
                : mojom::MediaSessionInfo::SessionState::kSuspended,
            GetState(&media_session_1));
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_2));

  // A call to `StartDuckingAllAudio()` with an exempted request ID should duck
  // all sessions except the exempted one.
  StartDuckingAllAudio(id_2);
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kDucking,
            GetState(&media_session_1));
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_2));

  // Once ducking all audio is stopped, the sessions should no longer be ducked.
  StopDuckingAllAudio();
  EXPECT_EQ(IsGroupingEnabled()
                ? mojom::MediaSessionInfo::SessionState::kActive
                : mojom::MediaSessionInfo::SessionState::kSuspended,
            GetState(&media_session_1));
  EXPECT_EQ(mojom::MediaSessionInfo::SessionState::kActive,
            GetState(&media_session_2));
}

}  // namespace media_session