dom/media/mediacontrol/MediaControlKeySource.h

   1 /* This Source Code Form is subject to the terms of the Mozilla Public
   2  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
   3  * You can obtain one at http://mozilla.org/MPL/2.0/. */
   4
   5 #ifndef DOM_MEDIA_MEDIACONTROL_MEDIACONTROLKEYSOURCE_H_
   6 #define DOM_MEDIA_MEDIACONTROL_MEDIACONTROLKEYSOURCE_H_
   7
   8 #include "mozilla/Maybe.h"
   9 #include "mozilla/dom/MediaControllerBinding.h"
  10 #include "mozilla/dom/MediaMetadata.h"
  11 #include "mozilla/dom/MediaSession.h"
  12 #include "mozilla/dom/MediaSessionBinding.h"
  13 #include "nsISupportsImpl.h"
  14 #include "nsTArray.h"
  15
  16 namespace mozilla::dom {
  17
  18 // This is used to store seek related properties from MediaSessionActionDetails.
  19 // https://w3c.github.io/mediasession/#the-mediasessionactiondetails-dictionary
  20 struct AbsoluteSeek {
  21   double mSeekTime;
  22   bool mFastSeek;
  23 };
  24 struct SeekDetails {
  25   Maybe<AbsoluteSeek> mAbsolute;
  26   Maybe<double> mRelativeSeekOffset;
  27
  28   SeekDetails() = default;
  29   SeekDetails(double aSeekTime, bool aFastSeek)
  30       : mAbsolute(Some(AbsoluteSeek{aSeekTime, aFastSeek})) {}
  31   explicit SeekDetails(double aRelativeSeekOffset)
  32       : mRelativeSeekOffset(Some(aRelativeSeekOffset)) {}
  33 };
  34
  35 struct MediaControlAction {
  36   MediaControlAction() = default;
  37   explicit MediaControlAction(MediaControlKey aKey) : mKey(Some(aKey)) {}
  38   MediaControlAction(MediaControlKey aKey, const SeekDetails& aDetails)
  39       : mKey(Some(aKey)), mDetails(Some(aDetails)) {}
  40   Maybe<MediaControlKey> mKey;
  41   Maybe<SeekDetails> mDetails;
  42 };
  43
  44 /**
  45  * MediaControlKeyListener is a pure interface, which is used to monitor
  46  * MediaControlKey, we can add it onto the MediaControlKeySource,
  47  * and then everytime when the media key events occur, `OnActionPerformed` will
  48  * be called so that we can do related handling.
  49  */
  50 class MediaControlKeyListener {
  51  public:
  52   NS_INLINE_DECL_PURE_VIRTUAL_REFCOUNTING
  53   MediaControlKeyListener() = default;
  54
  55   virtual void OnActionPerformed(const MediaControlAction& aAction) = 0;
  56
  57  protected:
  58   virtual ~MediaControlKeyListener() = default;
  59 };
  60
  61 /**
  62  * MediaControlKeyHandler is used to operate media controller by corresponding
  63  * received media control key events.
  64  */
  65 class MediaControlKeyHandler final : public MediaControlKeyListener {
  66  public:
  67   NS_INLINE_DECL_REFCOUNTING(MediaControlKeyHandler, override)
  68   void OnActionPerformed(const MediaControlAction& aAction) override;
  69
  70  private:
  71   virtual ~MediaControlKeyHandler() = default;
  72 };
  73
  74 /**
  75  * MediaControlKeySource is an abstract class which is used to implement
  76  * transporting media control keys event to all its listeners when media keys
  77  * event happens.
  78  */
  79 class MediaControlKeySource {
  80  public:
  81   NS_INLINE_DECL_PURE_VIRTUAL_REFCOUNTING
  82   MediaControlKeySource();
  83
  84   using MediaKeysArray = nsTArray<MediaControlKey>;
  85
  86   virtual void AddListener(MediaControlKeyListener* aListener);
  87   virtual void RemoveListener(MediaControlKeyListener* aListener);
  88   size_t GetListenersNum() const;
  89
  90   // Return true if the initialization of the source succeeds, and inherited
  91   // sources should implement this method to handle the initialization fails.
  92   virtual bool Open() = 0;
  93   virtual void Close();
  94   virtual bool IsOpened() const = 0;
  95
  96   /**
  97    * All following `SetXXX()` functions are used to update the playback related
  98    * properties change from a specific tab, which can represent the playback
  99    * status for Firefox instance. Even if we have multiple tabs playing media at
 100    * the same time, we would only update information from one of that tabs that
 101    * would be done by `MediaControlService`.
 102    */
 103   virtual void SetPlaybackState(MediaSessionPlaybackState aState);
 104   virtual MediaSessionPlaybackState GetPlaybackState() const;
 105
 106   // Override this method if the event source needs to handle the metadata.
 107   virtual void SetMediaMetadata(const MediaMetadataBase& aMetadata) {}
 108
 109   // Set the supported media keys which the event source can use to determine
 110   // what kinds of buttons should be shown on the UI.
 111   virtual void SetSupportedMediaKeys(const MediaKeysArray& aSupportedKeys) = 0;
 112
 113   // Override these methods if the inherited key source want to know the change
 114   // for following attributes. For example, GeckoView would use these methods
 115   // to notify change to the embedded application.
 116   virtual void SetEnableFullScreen(bool aIsEnabled) {};
 117   virtual void SetEnablePictureInPictureMode(bool aIsEnabled) {};
 118   virtual void SetPositionState(const Maybe<PositionState>& aState) {};
 119
 120  protected:
 121   virtual ~MediaControlKeySource() = default;
 122   nsTArray<RefPtr<MediaControlKeyListener>> mListeners;
 123   MediaSessionPlaybackState mPlaybackState;
 124 };
 125
 126 }  // namespace mozilla::dom
 127
 128 #endif