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diff --git a/dom/media/utils/TelemetryProbesReporter.h b/dom/media/utils/TelemetryProbesReporter.h
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+++ b/dom/media/utils/TelemetryProbesReporter.h
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+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef DOM_TelemetryProbesReporter_H_
+#define DOM_TelemetryProbesReporter_H_
+
+#include "MediaInfo.h"
+#include "mozilla/Maybe.h"
+#include "mozilla/AwakeTimeStamp.h"
+#include "AudioChannelService.h"
+#include "nsISupportsImpl.h"
+
+namespace mozilla {
+class FrameStatistics;
+
+class TelemetryProbesReporterOwner {
+ public:
+  virtual Maybe<nsAutoString> GetKeySystem() const = 0;
+  virtual MediaInfo GetMediaInfo() const = 0;
+  virtual FrameStatistics* GetFrameStatistics() const = 0;
+  virtual bool IsEncrypted() const = 0;
+  virtual void DispatchAsyncTestingEvent(const nsAString& aName) = 0;
+};
+
+enum class MediaContent : uint8_t {
+  MEDIA_HAS_NOTHING = (0 << 0),
+  MEDIA_HAS_VIDEO = (1 << 0),
+  MEDIA_HAS_AUDIO = (1 << 1),
+  MEDIA_HAS_COLOR_DEPTH_ABOVE_8 = (1 << 2),
+};
+
+MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(MediaContent)
+
+/**
+ * This class is used for collecting and reporting telemetry probes for
+ * its owner which should inherit from TelemetryProbesReporterOwner. We use it
+ * for HTMLMediaElement, and each element has one corresponding reporter.
+ */
+class TelemetryProbesReporter final {
+ public:
+  explicit TelemetryProbesReporter(TelemetryProbesReporterOwner* aOwner);
+  ~TelemetryProbesReporter() = default;
+
+  enum class Visibility {
+    eInitial,
+    eVisible,
+    eInvisible,
+  };
+
+  static MediaContent MediaInfoToMediaContent(const MediaInfo& aInfo);
+
+  using AudibleState = dom::AudioChannelService::AudibleState;
+
+  // State transitions
+  void OnPlay(Visibility aVisibility, MediaContent aContent, bool aIsMuted);
+  void OnPause(Visibility aVisibility);
+  void OnShutdown();
+
+  void OnVisibilityChanged(Visibility aVisibility);
+  void OnAudibleChanged(AudibleState aAudible);
+  void OnMediaContentChanged(MediaContent aContent);
+  void OnMutedChanged(bool aMuted);
+  void OnDecodeSuspended();
+  void OnDecodeResumed();
+
+  double GetTotalVideoPlayTimeInSeconds() const;
+  double GetTotalVideoHDRPlayTimeInSeconds() const;
+  double GetVisibleVideoPlayTimeInSeconds() const;
+  double GetInvisibleVideoPlayTimeInSeconds() const;
+  double GetVideoDecodeSuspendedTimeInSeconds() const;
+
+  double GetTotalAudioPlayTimeInSeconds() const;
+  double GetInaudiblePlayTimeInSeconds() const;
+  double GetAudiblePlayTimeInSeconds() const;
+  double GetMutedPlayTimeInSeconds() const;
+
+ private:
+  void StartInvisibleVideoTimeAccumulator();
+  void PauseInvisibleVideoTimeAccumulator();
+  void StartInaudibleAudioTimeAccumulator();
+  void PauseInaudibleAudioTimeAccumulator();
+  void StartMutedAudioTimeAccumulator();
+  void PauseMutedAudioTimeAccumulator();
+  bool HasOwnerHadValidVideo() const;
+  bool HasOwnerHadValidMedia() const;
+  void AssertOnMainThreadAndNotShutdown() const;
+
+  void ReportTelemetry();
+  void ReportResultForVideo();
+  void ReportResultForAudio();
+  void ReportResultForVideoFrameStatistics(double aTotalPlayTimeS,
+                                           const nsCString& key);
+
+  // Helper class to measure times for playback telemetry stats
+  class TimeDurationAccumulator {
+   public:
+    TimeDurationAccumulator() = default;
+    void Start() {
+      if (IsStarted()) {
+        return;
+      }
+      mStartTime = Some(AwakeTimeStamp::NowLoRes());
+    }
+    void Pause() {
+      if (!IsStarted()) {
+        return;
+      }
+      mSum = (AwakeTimeStamp::NowLoRes() - mStartTime.value());
+      mStartTime = Nothing();
+    }
+    bool IsStarted() const { return mStartTime.isSome(); }
+
+    double GetAndClearTotal() {
+      MOZ_ASSERT(!IsStarted(), "only call this when accumulator is paused");
+      double total = mSum.ToSeconds();
+      mStartTime = Nothing();
+      mSum = AwakeTimeDuration();
+      return total;
+    }
+
+    double PeekTotal() const {
+      if (!IsStarted()) {
+        return mSum.ToSeconds();
+      }
+      return (AwakeTimeStamp::NowLoRes() - mStartTime.value()).ToSeconds();
+    }
+
+   private:
+    Maybe<AwakeTimeStamp> mStartTime;
+    AwakeTimeDuration mSum;
+  };
+
+  // The owner is HTMLMediaElement that is guaranteed being always alive during
+  // our whole life cycle.
+  TelemetryProbesReporterOwner* mOwner;
+
+  // Total time an element has spent on playing video.
+  TimeDurationAccumulator mTotalVideoPlayTime;
+
+  // Total time an element has spent on playing video that has a color depth
+  // greater than 8, which is likely HDR video.
+  TimeDurationAccumulator mTotalVideoHDRPlayTime;
+
+  // Total time an element has spent on playing audio
+  TimeDurationAccumulator mTotalAudioPlayTime;
+
+  // Total time a VIDEO element has spent playing while the corresponding media
+  // element is invisible.
+  TimeDurationAccumulator mInvisibleVideoPlayTime;
+
+  // Total time an element has spent playing audio that was not audible
+  TimeDurationAccumulator mInaudibleAudioPlayTime;
+
+  // Total time an element with an audio track has spent muted
+  TimeDurationAccumulator mMutedAudioPlayTime;
+
+  // Total time a VIDEO has spent in video-decode-suspend mode.
+  TimeDurationAccumulator mVideoDecodeSuspendedTime;
+
+  Visibility mMediaElementVisibility = Visibility::eInitial;
+
+  MediaContent mMediaContent = MediaContent::MEDIA_HAS_NOTHING;
+
+  bool mIsPlaying = false;
+
+  bool mIsMuted = false;
+};
+
+}  // namespace mozilla
+
+#endif  // DOM_TelemetryProbesReporter_H_