/*
 * Copyright (C) 2013 Google 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:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * 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.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 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 THE COPYRIGHT
 * OWNER OR 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.
 */

#ifndef InterceptingCanvas_h
#define InterceptingCanvas_h

#include "third_party/skia/include/core/SkCanvas.h"
#include "third_party/skia/include/core/SkPicture.h"
#include "wtf/Allocator.h"
#include "wtf/Assertions.h"
#include "wtf/Noncopyable.h"

namespace blink {

class InterceptingCanvasBase : public SkCanvas {
  WTF_MAKE_NONCOPYABLE(InterceptingCanvasBase);

 public:
  template <typename DerivedCanvas>
  class CanvasInterceptorBase {
    STACK_ALLOCATED();
    WTF_MAKE_NONCOPYABLE(CanvasInterceptorBase);

   protected:
    CanvasInterceptorBase(InterceptingCanvasBase* canvas) : m_canvas(canvas) {
      ++m_canvas->m_callNestingDepth;
    }

    ~CanvasInterceptorBase() {
      ASSERT(m_canvas->m_callNestingDepth > 0);
      if (!--m_canvas->m_callNestingDepth)
        m_canvas->m_callCount++;
    }

    DerivedCanvas* canvas() { return static_cast<DerivedCanvas*>(m_canvas); }
    bool topLevelCall() const { return m_canvas->callNestingDepth() == 1; }
    InterceptingCanvasBase* m_canvas;
  };

  void resetStepCount() { m_callCount = 0; }

 protected:
  explicit InterceptingCanvasBase(SkBitmap bitmap)
      : SkCanvas(bitmap), m_callNestingDepth(0), m_callCount(0) {}
  InterceptingCanvasBase(int width, int height)
      : SkCanvas(width, height), m_callNestingDepth(0), m_callCount(0) {}

  void unrollDrawPicture(const SkPicture*,
                         const SkMatrix*,
                         const SkPaint*,
                         SkPicture::AbortCallback*);

  void onDrawPaint(const SkPaint&) override = 0;
  void onDrawPoints(PointMode,
                    size_t count,
                    const SkPoint pts[],
                    const SkPaint&) override = 0;
  void onDrawRect(const SkRect&, const SkPaint&) override = 0;
  void onDrawOval(const SkRect&, const SkPaint&) override = 0;
  void onDrawRRect(const SkRRect&, const SkPaint&) override = 0;
  void onDrawPath(const SkPath&, const SkPaint&) override = 0;
  void onDrawBitmap(const SkBitmap&,
                    SkScalar left,
                    SkScalar top,
                    const SkPaint*) override = 0;
  void onDrawBitmapRect(const SkBitmap&,
                        const SkRect* src,
                        const SkRect& dst,
                        const SkPaint*,
                        SrcRectConstraint) override = 0;
  void onDrawBitmapNine(const SkBitmap&,
                        const SkIRect& center,
                        const SkRect& dst,
                        const SkPaint*) override = 0;
  void onDrawImage(const SkImage*,
                   SkScalar,
                   SkScalar,
                   const SkPaint*) override = 0;
  void onDrawImageRect(const SkImage*,
                       const SkRect* src,
                       const SkRect& dst,
                       const SkPaint*,
                       SrcRectConstraint) override = 0;
  void onDrawVertices(VertexMode vmode,
                      int vertexCount,
                      const SkPoint vertices[],
                      const SkPoint texs[],
                      const SkColor colors[],
                      SkBlendMode bmode,
                      const uint16_t indices[],
                      int indexCount,
                      const SkPaint&) override = 0;

  void onDrawDRRect(const SkRRect& outer,
                    const SkRRect& inner,
                    const SkPaint&) override = 0;
  void onDrawText(const void* text,
                  size_t byteLength,
                  SkScalar x,
                  SkScalar y,
                  const SkPaint&) override = 0;
  void onDrawPosText(const void* text,
                     size_t byteLength,
                     const SkPoint pos[],
                     const SkPaint&) override = 0;
  void onDrawPosTextH(const void* text,
                      size_t byteLength,
                      const SkScalar xpos[],
                      SkScalar constY,
                      const SkPaint&) override = 0;
  void onDrawTextOnPath(const void* text,
                        size_t byteLength,
                        const SkPath&,
                        const SkMatrix*,
                        const SkPaint&) override = 0;
  void onDrawTextBlob(const SkTextBlob*,
                      SkScalar x,
                      SkScalar y,
                      const SkPaint&) override = 0;
  void onClipRect(const SkRect&, SkClipOp, ClipEdgeStyle) override = 0;
  void onClipRRect(const SkRRect&, SkClipOp, ClipEdgeStyle) override = 0;
  void onClipPath(const SkPath&, SkClipOp, ClipEdgeStyle) override = 0;
  void onClipRegion(const SkRegion&, SkClipOp) override = 0;
  void onDrawPicture(const SkPicture*,
                     const SkMatrix*,
                     const SkPaint*) override = 0;
  void didSetMatrix(const SkMatrix&) override = 0;
  void didConcat(const SkMatrix&) override = 0;
  void willSave() override = 0;
  SaveLayerStrategy getSaveLayerStrategy(const SaveLayerRec&) override = 0;
  void willRestore() override = 0;

  unsigned callNestingDepth() const { return m_callNestingDepth; }
  unsigned callCount() const { return m_callCount; }

 private:
  unsigned m_callNestingDepth;
  unsigned m_callCount;
};

template <typename DerivedCanvas>
class CanvasInterceptor {};

template <typename DerivedCanvas,
          typename Interceptor = CanvasInterceptor<DerivedCanvas>>
class InterceptingCanvas : public InterceptingCanvasBase {
 protected:
  explicit InterceptingCanvas(SkBitmap bitmap)
      : InterceptingCanvasBase(bitmap) {}
  InterceptingCanvas(int width, int height)
      : InterceptingCanvasBase(width, height) {}

  void onDrawPaint(const SkPaint& paint) override {
    Interceptor interceptor(this);
    this->SkCanvas::onDrawPaint(paint);
  }

  void onDrawPoints(PointMode mode,
                    size_t count,
                    const SkPoint pts[],
                    const SkPaint& paint) override {
    Interceptor interceptor(this);
    this->SkCanvas::onDrawPoints(mode, count, pts, paint);
  }

  void onDrawRect(const SkRect& rect, const SkPaint& paint) override {
    Interceptor interceptor(this);
    this->SkCanvas::onDrawRect(rect, paint);
  }

  void onDrawOval(const SkRect& rect, const SkPaint& paint) override {
    Interceptor interceptor(this);
    this->SkCanvas::onDrawOval(rect, paint);
  }

  void onDrawRRect(const SkRRect& rrect, const SkPaint& paint) override {
    Interceptor interceptor(this);
    this->SkCanvas::onDrawRRect(rrect, paint);
  }

  void onDrawPath(const SkPath& path, const SkPaint& paint) override {
    Interceptor interceptor(this);
    this->SkCanvas::onDrawPath(path, paint);
  }

  void onDrawBitmap(const SkBitmap& bitmap,
                    SkScalar left,
                    SkScalar top,
                    const SkPaint* paint) override {
    Interceptor interceptor(this);
    this->SkCanvas::onDrawBitmap(bitmap, left, top, paint);
  }

  void onDrawBitmapRect(const SkBitmap& bitmap,
                        const SkRect* src,
                        const SkRect& dst,
                        const SkPaint* paint,
                        SrcRectConstraint constraint) override {
    Interceptor interceptor(this);
    this->SkCanvas::onDrawBitmapRect(bitmap, src, dst, paint, constraint);
  }

  void onDrawBitmapNine(const SkBitmap& bitmap,
                        const SkIRect& center,
                        const SkRect& dst,
                        const SkPaint* paint) override {
    Interceptor interceptor(this);
    this->SkCanvas::onDrawBitmapNine(bitmap, center, dst, paint);
  }

  void onDrawImage(const SkImage* image,
                   SkScalar x,
                   SkScalar y,
                   const SkPaint* paint) override {
    Interceptor interceptor(this);
    this->SkCanvas::onDrawImage(image, x, y, paint);
  }

  void onDrawImageRect(const SkImage* image,
                       const SkRect* src,
                       const SkRect& dst,
                       const SkPaint* paint,
                       SrcRectConstraint constraint) override {
    Interceptor interceptor(this);
    this->SkCanvas::onDrawImageRect(image, src, dst, paint, constraint);
  }

  void onDrawVertices(VertexMode vmode,
                      int vertexCount,
                      const SkPoint vertices[],
                      const SkPoint texs[],
                      const SkColor colors[],
                      SkBlendMode bmode,
                      const uint16_t indices[],
                      int indexCount,
                      const SkPaint& paint) override {
    Interceptor interceptor(this);
    this->SkCanvas::onDrawVertices(vmode, vertexCount, vertices, texs, colors,
                                   bmode, indices, indexCount, paint);
  }

  void onDrawDRRect(const SkRRect& outer,
                    const SkRRect& inner,
                    const SkPaint& paint) override {
    Interceptor interceptor(this);
    this->SkCanvas::onDrawDRRect(outer, inner, paint);
  }

  void onDrawText(const void* text,
                  size_t byteLength,
                  SkScalar x,
                  SkScalar y,
                  const SkPaint& paint) override {
    Interceptor interceptor(this);
    this->SkCanvas::onDrawText(text, byteLength, x, y, paint);
  }

  void onDrawPosText(const void* text,
                     size_t byteLength,
                     const SkPoint pos[],
                     const SkPaint& paint) override {
    Interceptor interceptor(this);
    this->SkCanvas::onDrawPosText(text, byteLength, pos, paint);
  }

  void onDrawPosTextH(const void* text,
                      size_t byteLength,
                      const SkScalar xpos[],
                      SkScalar constY,
                      const SkPaint& paint) override {
    Interceptor interceptor(this);
    this->SkCanvas::onDrawPosTextH(text, byteLength, xpos, constY, paint);
  }

  void onDrawTextOnPath(const void* text,
                        size_t byteLength,
                        const SkPath& path,
                        const SkMatrix* matrix,
                        const SkPaint& paint) override {
    Interceptor interceptor(this);
    this->SkCanvas::onDrawTextOnPath(text, byteLength, path, matrix, paint);
  }

  void onDrawTextBlob(const SkTextBlob* blob,
                      SkScalar x,
                      SkScalar y,
                      const SkPaint& paint) override {
    Interceptor interceptor(this);
    this->SkCanvas::onDrawTextBlob(blob, x, y, paint);
  }

  void onClipRect(const SkRect& rect,
                  SkClipOp op,
                  ClipEdgeStyle edgeStyle) override {
    Interceptor interceptor(this);
    this->SkCanvas::onClipRect(rect, op, edgeStyle);
  }

  void onClipRRect(const SkRRect& rrect,
                   SkClipOp op,
                   ClipEdgeStyle edgeStyle) override {
    Interceptor interceptor(this);
    this->SkCanvas::onClipRRect(rrect, op, edgeStyle);
  }

  void onClipPath(const SkPath& path,
                  SkClipOp op,
                  ClipEdgeStyle edgeStyle) override {
    Interceptor interceptor(this);
    this->SkCanvas::onClipPath(path, op, edgeStyle);
  }

  void onClipRegion(const SkRegion& region, SkClipOp op) override {
    Interceptor interceptor(this);
    this->SkCanvas::onClipRegion(region, op);
  }

  void onDrawPicture(const SkPicture* picture,
                     const SkMatrix* matrix,
                     const SkPaint* paint) override {
    this->unrollDrawPicture(picture, matrix, paint, nullptr);
  }

  void didSetMatrix(const SkMatrix& matrix) override {
    Interceptor interceptor(this);
    this->SkCanvas::didSetMatrix(matrix);
  }

  void didConcat(const SkMatrix& matrix) override {
    Interceptor interceptor(this);
    this->SkCanvas::didConcat(matrix);
  }

  void willSave() override {
    Interceptor interceptor(this);
    this->SkCanvas::willSave();
  }

  SkCanvas::SaveLayerStrategy getSaveLayerStrategy(
      const SaveLayerRec& rec) override {
    Interceptor interceptor(this);
    return this->SkCanvas::getSaveLayerStrategy(rec);
  }

  void willRestore() override {
    Interceptor interceptor(this);
    this->SkCanvas::willRestore();
  }
};

}  // namespace blink

#endif  // InterceptingCanvas_h