// Copyright 2013 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef THIRD_PARTY_BLINK_RENDERER_MODULES_MEDIASTREAM_MEDIA_STREAM_VIDEO_TRACK_H_
#define THIRD_PARTY_BLINK_RENDERER_MODULES_MEDIASTREAM_MEDIA_STREAM_VIDEO_TRACK_H_

#include "base/compiler_specific.h"
#include "base/gtest_prod_util.h"
#include "base/memory/weak_ptr.h"
#include "base/threading/thread_checker.h"
#include "base/timer/timer.h"
#include "third_party/blink/public/platform/modules/mediastream/secure_display_link_tracker.h"
#include "third_party/blink/public/platform/modules/mediastream/web_media_stream_sink.h"
#include "third_party/blink/public/platform/modules/mediastream/web_media_stream_track.h"
#include "third_party/blink/public/web/modules/mediastream/encoded_video_frame.h"
#include "third_party/blink/public/web/modules/mediastream/media_stream_video_sink.h"
#include "third_party/blink/public/web/modules/mediastream/media_stream_video_source.h"
#include "third_party/blink/renderer/modules/mediastream/image_capture_device_settings.h"
#include "third_party/blink/renderer/modules/mediastream/video_track_adapter_settings.h"
#include "third_party/blink/renderer/modules/modules_export.h"
#include "third_party/blink/renderer/platform/mediastream/media_stream_track_platform.h"
#include "third_party/blink/renderer/platform/wtf/hash_set.h"
#include "third_party/blink/renderer/platform/wtf/vector.h"
#include "ui/gfx/geometry/size.h"

namespace blink {

// MediaStreamVideoTrack is a video-specific representation of a
// MediaStreamTrackPlatform. It is owned by a MediaStreamComponent
// and can be retrieved using MediaStreamComponent::GetPlatformTrack().
class MODULES_EXPORT MediaStreamVideoTrack : public MediaStreamTrackPlatform {
 public:
  // Help method to create a WebMediaStreamTrack and a
  // MediaStreamVideoTrack instance. The MediaStreamVideoTrack object is owned
  // by the blink object in its WebMediaStreamTrack::GetPlatformTrack() member.
  // |callback| is triggered if the track is added to the source
  // successfully and will receive video frames that match the given settings
  // or if the source fails to provide video frames.
  // If |enabled| is true, sinks added to the track will
  // receive video frames when the source delivers frames to the track.
  static WebMediaStreamTrack CreateVideoTrack(
      MediaStreamVideoSource* source,
      MediaStreamVideoSource::ConstraintsOnceCallback callback,
      bool enabled);
  static WebMediaStreamTrack CreateVideoTrack(
      MediaStreamVideoSource* source,
      const VideoTrackAdapterSettings& adapter_settings,
      const std::optional<bool>& noise_reduction,
      bool is_screencast,
      const std::optional<double>& min_frame_rate,
      const ImageCaptureDeviceSettings* image_capture_device_settings,
      bool pan_tilt_zoom_allowed,
      MediaStreamVideoSource::ConstraintsOnceCallback callback,
      bool enabled);

  static MediaStreamVideoTrack* From(const MediaStreamComponent* track);

  // Constructors for video tracks.
  MediaStreamVideoTrack(
      MediaStreamVideoSource* source,
      MediaStreamVideoSource::ConstraintsOnceCallback callback,
      bool enabled);
  MediaStreamVideoTrack(
      MediaStreamVideoSource* source,
      const VideoTrackAdapterSettings& adapter_settings,
      const std::optional<bool>& noise_reduction,
      bool is_screen_cast,
      const std::optional<double>& min_frame_rate,
      const ImageCaptureDeviceSettings* image_capture_device_settings,
      bool pan_tilt_zoom_allowed,
      MediaStreamVideoSource::ConstraintsOnceCallback callback,
      bool enabled);

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

  ~MediaStreamVideoTrack() override;

  std::unique_ptr<MediaStreamTrackPlatform> CreateFromComponent(
      const MediaStreamComponent* component,
      const String& id) override;

  // MediaStreamTrackPlatform overrides.
  void SetEnabled(bool enabled) override;
  void SetContentHint(
      WebMediaStreamTrack::ContentHintType content_hint) override;
  void StopAndNotify(base::OnceClosure callback) override;
  void GetSettings(MediaStreamTrackPlatform::Settings& settings) const override;
  MediaStreamTrackPlatform::VideoFrameStats GetVideoFrameStats() const override;
  MediaStreamTrackPlatform::CaptureHandle GetCaptureHandle() override;
  void AddCaptureVersionCallback(media::CaptureVersion capture_version,
                                 base::OnceClosure callback) override;
  void RemoveCaptureVersionCallback(
      media::CaptureVersion capture_version) override;

  // Add |sink| to receive state changes on the main render thread and video
  // frames in the |callback| method on the video task runner.
  // |callback| will be reset on the render thread.
  void AddSink(WebMediaStreamSink* sink,
               const VideoCaptureDeliverFrameCB& callback,
               MediaStreamVideoSink::IsSecure is_secure,
               MediaStreamVideoSink::UsesAlpha uses_alpha) override;
  // Sets |sink|'s dropped frame notification callback which will receive calls
  // on the video task runner. |callback| will be reset on the render thread.
  // Note: the method needs to be called after a sink has been added.
  void SetSinkNotifyFrameDroppedCallback(
      WebMediaStreamSink* sink,
      const VideoCaptureNotifyFrameDroppedCB& callback);
  void RemoveSink(WebMediaStreamSink* sink);

  // Returns the number of currently connected sinks.
  size_t CountSinks() const;

  // Adds |callback| for encoded frame output on the video task runner. The
  // function will cause generation of a keyframe from the source. Encoded sinks
  // are not secure.
  void AddEncodedSink(WebMediaStreamSink* sink, EncodedVideoFrameCB callback);

  // Removes encoded callbacks associated with |sink|.
  void RemoveEncodedSink(WebMediaStreamSink* sink);

  // Returns the number of currently present encoded sinks.
  size_t CountEncodedSinks() const;

  void OnReadyStateChanged(WebMediaStreamSource::ReadyState state);

  // Registers callback that is triggered whenever the delivered frame's
  // metadata source_size or device_scale_factor changes.
  void RegisterCaptureSurfaceResolutionChangeCallback(
      base::RepeatingCallback<void(bool)> callback) {
    captured_surface_resolution_callback_ = std::move(callback);
  }

  const std::optional<bool>& noise_reduction() const {
    return noise_reduction_;
  }
  bool is_screencast() const { return is_screencast_; }
  const std::optional<double>& min_frame_rate() const {
    return min_frame_rate_;
  }
  std::optional<double> max_frame_rate() const {
    return adapter_settings_.max_frame_rate();
  }
  const VideoTrackAdapterSettings& adapter_settings() const {
    return adapter_settings_;
  }
  const std::optional<ImageCaptureDeviceSettings>&
  image_capture_device_settings() const {
    return image_capture_device_settings_;
  }
  bool pan_tilt_zoom_allowed() const { return pan_tilt_zoom_allowed_; }

  // Setting information about the track size.
  // Called from MediaStreamVideoSource at track initialization.
  void SetTargetSize(int width, int height) {
    width_ = width;
    height_ = height;
  }

  // Setting information about the track size.
  // Passed as callback on MediaStreamVideoTrack::AddTrack, and run from
  // VideoFrameResolutionAdapter on frame delivery to update track settings.
  void SetVideoFrameSettings(gfx::Size frame_size,
                             double frame_rate,
                             std::optional<gfx::Size> metadata_source_size,
                             std::optional<float> device_scale_factor);

  // Setting information about the source format. The format is computed based
  // on incoming frames and it's used for applying constraints for remote video
  // tracks. Passed as callback on MediaStreamVideoTrack::AddTrack, and run from
  // VideoFrameResolutionAdapter on frame delivery.
  void set_computed_source_format(const media::VideoCaptureFormat& format) {
    computed_source_format_ = format;
  }

  // Track constraints setup.
  void SetMinimumFrameRate(double min_frame_rate);
  void SetTrackAdapterSettings(const VideoTrackAdapterSettings& settings);

  // Signals that track configuration with
  // SetMinimumFrameRate/SetTrackAdapterSettings is complete. Notifies sinks on
  // new constraints.
  void NotifyConstraintsConfigurationComplete();

  media::VideoCaptureFormat GetComputedSourceFormat();

  MediaStreamVideoSource* source() const { return source_.get(); }

  // Sink dropping frames affects logging and UMAs, but not the MediaStreamTrack
  // Statistics API since such frames were delivered to the sink before drop.
  void OnSinkDroppedFrame(media::VideoCaptureFrameDropReason reason);

  bool IsRefreshFrameTimerRunningForTesting() {
    return refresh_timer_.IsRunning();
  }

  void SetIsScreencastForTesting(bool is_screencast) {
    is_screencast_ = is_screencast;
  }

  MediaStreamTrackPlatform::StreamType Type() const override {
    return MediaStreamTrackPlatform::StreamType::kVideo;
  }

  bool UsingAlpha() const;

  // Return either the configured target size, or the size of the last observed
  // frame. If both happened - return the more recent. If neither happened -
  // return gfx::Size(0, 0).
  gfx::Size GetVideoSize() const;

  // After this many frame drops of the same reason, we skip logging
  // Media.VideoCapture.Track.FrameDrop UMAs.
  static constexpr int kMaxConsecutiveFrameDropForSameReasonCount = 10;

  // After this many frame drops of the same reason, we suppress
  // EmitLogMessage(), which is wired to MediaStreamVideoSource::OnLog() and
  // ultimately WebRTC logging in the browser process.
  static constexpr int kMaxEmittedLogsForDroppedFramesBeforeSuppressing = 3;
  // Suppressed logs for dropped frames will still be emitted this often.
  static constexpr int kFrequencyForSuppressedLogs = 100;

  void SetEmitLogMessageForTesting(
      base::RepeatingCallback<void(const std::string&)> emit_log_message);

 private:
  FRIEND_TEST_ALL_PREFIXES(MediaStreamRemoteVideoSourceTest, StartTrack);
  FRIEND_TEST_ALL_PREFIXES(MediaStreamRemoteVideoSourceTest, RemoteTrackStop);
  FRIEND_TEST_ALL_PREFIXES(MediaStreamRemoteVideoSourceTest,
                           PreservesColorSpace);
  FRIEND_TEST_ALL_PREFIXES(PepperToVideoTrackAdapterTest, PutFrame);

  void UpdateSourceCapturingSecure();
  void UpdateSourceHasConsumers();

  void RequestRefreshFrame();
  void StartTimerForRequestingFrames();
  void ResetRefreshTimer();

  // In debug builds, check that all methods that could cause object graph
  // or data flow changes are being called on the main thread.
  THREAD_CHECKER(main_render_thread_checker_);

  Vector<WebMediaStreamSink*> sinks_;
  Vector<WebMediaStreamSink*> encoded_sinks_;

  // |FrameDeliverer| is an internal helper object used for delivering video
  // frames on the video task runner using callbacks to all registered tracks.
  class FrameDeliverer;
  scoped_refptr<FrameDeliverer> frame_deliverer_;

  VideoTrackAdapterSettings adapter_settings_;
  std::optional<bool> noise_reduction_;
  bool is_screencast_;
  std::optional<double> min_frame_rate_;
  std::optional<ImageCaptureDeviceSettings> image_capture_device_settings_;
  bool pan_tilt_zoom_allowed_ = false;

  // Weak ref to the source this tracks is connected to.
  base::WeakPtr<MediaStreamVideoSource> source_;

  // This is used for tracking if all connected video sinks are secure.
  SecureDisplayLinkTracker<WebMediaStreamSink> secure_tracker_;

  // This is used for tracking if no connected video use alpha.
  HashSet<WebMediaStreamSink*> alpha_using_sinks_;
  HashSet<WebMediaStreamSink*> alpha_discarding_sinks_;

  // Remembering our desired video size and frame rate.
  int width_ = 0;
  int height_ = 0;

  std::optional<gfx::Size> captured_frame_physical_size_;
  std::optional<float> device_scale_factor_;
  std::optional<double> computed_frame_rate_;
  media::VideoCaptureFormat computed_source_format_;
  base::RepeatingTimer refresh_timer_;
  base::RepeatingCallback<void(bool)> captured_surface_resolution_callback_;

  base::WeakPtrFactory<MediaStreamVideoTrack> weak_factory_{this};
};

}  // namespace blink

#endif  // THIRD_PARTY_BLINK_RENDERER_MODULES_MEDIASTREAM_MEDIA_STREAM_VIDEO_TRACK_H_