Source/WebCore/platform/audio/cocoa/MediaSessionManagerCocoa.h

/*
 * Copyright (C) 2018 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

#pragma once

#if PLATFORM(COCOA)

#include "AudioHardwareListener.h"
#include "GenericTaskQueue.h"
#include "PlatformMediaSessionManager.h"
#include "RemoteCommandListener.h"
#include <pal/system/SystemSleepListener.h>

namespace WebCore {

struct NowPlayingInfo;

class MediaSessionManagerCocoa
    : public PlatformMediaSessionManager
    , private RemoteCommandListenerClient
    , private PAL::SystemSleepListener::Client
    , private AudioHardwareListener::Client {
    WTF_MAKE_FAST_ALLOCATED;
public:
    MediaSessionManagerCocoa();
    
    void updateSessionState() final;
    void beginInterruption(PlatformMediaSession::InterruptionType) final;

    bool hasActiveNowPlayingSession() const final { return m_nowPlayingActive; }
    String lastUpdatedNowPlayingTitle() const final { return m_lastUpdatedNowPlayingTitle; }
    double lastUpdatedNowPlayingDuration() const final { return m_lastUpdatedNowPlayingDuration; }
    double lastUpdatedNowPlayingElapsedTime() const final { return m_lastUpdatedNowPlayingElapsedTime; }
    MediaSessionIdentifier lastUpdatedNowPlayingInfoUniqueIdentifier() const final { return m_lastUpdatedNowPlayingInfoUniqueIdentifier; }
    bool registeredAsNowPlayingApplication() const final { return m_registeredAsNowPlayingApplication; }
    void prepareToSendUserMediaPermissionRequest() final;

    static WEBCORE_EXPORT void clearNowPlayingInfo();
    static WEBCORE_EXPORT void setNowPlayingInfo(bool setAsNowPlayingApplication, const NowPlayingInfo&);

protected:
    void scheduleUpdateNowPlayingInfo() final;
    void updateNowPlayingInfo();

    void removeSession(PlatformMediaSession&) final;
    void addSession(PlatformMediaSession&) final;
    void setCurrentSession(PlatformMediaSession&) final;

    bool sessionWillBeginPlayback(PlatformMediaSession&) final;
    void sessionWillEndPlayback(PlatformMediaSession&, DelayCallingUpdateNowPlaying) override;
    void sessionDidEndRemoteScrubbing(const PlatformMediaSession&) final;
    void clientCharacteristicsChanged(PlatformMediaSession&) final;
    void sessionCanProduceAudioChanged() final;

    virtual void providePresentingApplicationPIDIfNecessary() { }

    PlatformMediaSession* nowPlayingEligibleSession();

private:
#if !RELEASE_LOG_DISABLED
    const char* logClassName() const override { return "MediaSessionManagerCocoa"; }
#endif

    // RemoteCommandListenerClient
    void didReceiveRemoteControlCommand(PlatformMediaSession::RemoteControlCommandType type, const PlatformMediaSession::RemoteCommandArgument* argument) final { processDidReceiveRemoteControlCommand(type, argument); }
    bool supportsSeeking() const final { return computeSupportsSeeking(); }

    // AudioHardwareListenerClient
    void audioHardwareDidBecomeActive() final { }
    void audioHardwareDidBecomeInactive() final { }
    void audioOutputDeviceChanged() final { updateSessionState(); }

    // PAL::SystemSleepListener
    void systemWillSleep() final { processSystemWillSleep(); }
    void systemDidWake() final { processSystemDidWake(); }

    bool m_nowPlayingActive { false };
    bool m_registeredAsNowPlayingApplication { false };

    // For testing purposes only.
    String m_lastUpdatedNowPlayingTitle;
    double m_lastUpdatedNowPlayingDuration { NAN };
    double m_lastUpdatedNowPlayingElapsedTime { NAN };
    MediaSessionIdentifier m_lastUpdatedNowPlayingInfoUniqueIdentifier;

    GenericTaskQueue<Timer> m_nowPlayingUpdateTaskQueue;

    std::unique_ptr<RemoteCommandListener> m_remoteCommandListener;
    std::unique_ptr<PAL::SystemSleepListener> m_systemSleepListener;
    RefPtr<AudioHardwareListener> m_audioHardwareListener;
};

}

#endif // PLATFORM(COCOA)