// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef RecordingImageBufferSurface_h
#define RecordingImageBufferSurface_h

#include "platform/graphics/GraphicsContext.h"
#include "platform/graphics/ImageBufferSurface.h"
#include "public/platform/WebThread.h"
#include "third_party/skia/include/core/SkRefCnt.h"
#include "wtf/Allocator.h"
#include "wtf/Noncopyable.h"
#include <memory>

namespace blink {

class ImageBuffer;
class RecordingImageBufferSurfaceTest;

class RecordingImageBufferFallbackSurfaceFactory {
  USING_FAST_MALLOC(RecordingImageBufferFallbackSurfaceFactory);
  WTF_MAKE_NONCOPYABLE(RecordingImageBufferFallbackSurfaceFactory);

 public:
  virtual std::unique_ptr<ImageBufferSurface> createSurface(const IntSize&,
                                                            OpacityMode,
                                                            sk_sp<SkColorSpace>,
                                                            SkColorType) = 0;
  virtual ~RecordingImageBufferFallbackSurfaceFactory() {}

 protected:
  RecordingImageBufferFallbackSurfaceFactory() {}
};

class PLATFORM_EXPORT RecordingImageBufferSurface : public ImageBufferSurface {
  WTF_MAKE_NONCOPYABLE(RecordingImageBufferSurface);
  USING_FAST_MALLOC(RecordingImageBufferSurface);

 public:
  // If the fallbackFactory is null the buffer surface should only be used
  // for one frame and should not be used for any operations which need a
  // raster surface, (i.e. writePixels).
  // Only #getRecord should be used to access the resulting frame.
  RecordingImageBufferSurface(
      const IntSize&,
      std::unique_ptr<RecordingImageBufferFallbackSurfaceFactory>
          fallbackFactory = nullptr,
      OpacityMode = NonOpaque,
      sk_sp<SkColorSpace> = nullptr,
      SkColorType = kN32_SkColorType);
  ~RecordingImageBufferSurface() override;

  // Implementation of ImageBufferSurface interfaces
  PaintCanvas* canvas() override;
  void disableDeferral(DisableDeferralReason) override;
  sk_sp<PaintRecord> getRecord() override;
  void flush(FlushReason) override;
  void didDraw(const FloatRect&) override;
  bool isValid() const override { return true; }
  bool isRecording() const override { return !m_fallbackSurface; }
  bool writePixels(const SkImageInfo& origInfo,
                   const void* pixels,
                   size_t rowBytes,
                   int x,
                   int y) override;
  void willOverwriteCanvas() override;
  void finalizeFrame() override;
  void doPaintInvalidation(const FloatRect&) override;
  void setImageBuffer(ImageBuffer*) override;
  sk_sp<SkImage> newImageSnapshot(AccelerationHint, SnapshotReason) override;
  void draw(GraphicsContext&,
            const FloatRect& destRect,
            const FloatRect& srcRect,
            SkBlendMode) override;
  bool isExpensiveToPaint() override;
  void setHasExpensiveOp() override { m_currentFrameHasExpensiveOp = true; }

  // Passthroughs to fallback surface
  bool restore() override;
  WebLayer* layer() const override;
  bool isAccelerated() const override;
  void setIsHidden(bool) override;

  // This enum is used in a UMA histogram.
  enum FallbackReason {
    FallbackReasonUnknown =
        0,  // This value should never appear in production histograms
    FallbackReasonCanvasNotClearedBetweenFrames = 1,
    FallbackReasonRunawayStateStack = 2,
    FallbackReasonWritePixels = 3,
    FallbackReasonFlushInitialClear = 4,
    FallbackReasonFlushForDrawImageOfWebGL = 5,
    FallbackReasonSnapshotForGetImageData = 6,
    FallbackReasonSnapshotForPaint = 8,
    FallbackReasonSnapshotForToDataURL = 9,
    FallbackReasonSnapshotForToBlob = 10,
    FallbackReasonSnapshotForCanvasListenerCapture = 11,
    FallbackReasonSnapshotForDrawImage = 12,
    FallbackReasonSnapshotForCreatePattern = 13,
    FallbackReasonExpensiveOverdrawHeuristic = 14,
    FallbackReasonTextureBackedPattern = 15,
    FallbackReasonDrawImageOfVideo = 16,
    FallbackReasonDrawImageOfAnimated2dCanvas = 17,
    FallbackReasonSubPixelTextAntiAliasingSupport = 18,
    FallbackReasonDrawImageWithTextureBackedSourceImage = 19,
    FallbackReasonSnapshotForTransferToImageBitmap = 20,
    FallbackReasonSnapshotForUnitTests =
        21,  // This value should never appear in production histograms
    FallbackReasonSnapshotGetCopiedImage = 22,
    FallbackReasonSnapshotWebGLDrawImageIntoBuffer = 23,
    FallbackReasonSnapshotForWebGLTexImage2D = 24,
    FallbackReasonSnapshotForWebGLTexSubImage2D = 25,
    FallbackReasonSnapshotForWebGLTexImage3D = 26,
    FallbackReasonSnapshotForWebGLTexSubImage3D = 27,
    FallbackReasonSnapshotForCopyToClipboard = 28,
    FallbackReasonSnapshotForCreateImageBitmap = 29,
    FallbackReasonCount,
  };

 private:
  friend class RecordingImageBufferSurfaceTest;  // for unit testing
  void fallBackToRasterCanvas(FallbackReason);
  void initializeCurrentFrame();
  bool finalizeFrameInternal(FallbackReason*);
  int approximateOpCount();

  std::unique_ptr<PaintRecorder> m_currentFrame;
  sk_sp<PaintRecord> m_previousFrame;
  std::unique_ptr<ImageBufferSurface> m_fallbackSurface;
  ImageBuffer* m_imageBuffer;
  int m_initialSaveCount;
  int m_currentFramePixelCount;
  int m_previousFramePixelCount;
  bool m_frameWasCleared;
  bool m_didRecordDrawCommandsInCurrentFrame;
  bool m_currentFrameHasExpensiveOp;
  bool m_previousFrameHasExpensiveOp;
  std::unique_ptr<RecordingImageBufferFallbackSurfaceFactory> m_fallbackFactory;
};

}  // namespace blink

#endif