// Copyright 2017 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.

#include <stddef.h>
#include <stdint.h>

#include "cc/paint/paint_op_buffer.h"
#include "cc/test/transfer_cache_test_helper.h"
#include "components/viz/test/test_context_provider.h"
#include "third_party/skia/include/core/SkSurface.h"
#include "third_party/skia/include/gpu/GrContext.h"

// Deserialize an arbitrary number of cc::PaintOps and raster them
// using gpu raster into an SkCanvas.
extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
  const size_t kMaxSerializedSize = 1000000;
  const size_t kRasterDimension = 32;

  SkImageInfo image_info = SkImageInfo::MakeN32(
      kRasterDimension, kRasterDimension, kOpaque_SkAlphaType);
  scoped_refptr<viz::TestContextProvider> context_provider =
      viz::TestContextProvider::Create();
  context_provider->BindToCurrentThread();
  sk_sp<SkSurface> surface = SkSurface::MakeRenderTarget(
      context_provider->GrContext(), SkBudgeted::kYes, image_info);
  SkCanvas* canvas = surface->getCanvas();

  cc::PlaybackParams params(nullptr, canvas->getTotalMatrix());
  cc::TransferCacheTestHelper transfer_cache_helper;
  cc::PaintOp::DeserializeOptions deserialize_options;
  deserialize_options.transfer_cache = &transfer_cache_helper;

  // Need 4 bytes to be able to read the type/skip.
  while (size >= 4) {
    const cc::PaintOp* serialized = reinterpret_cast<const cc::PaintOp*>(data);
    if (serialized->skip > kMaxSerializedSize)
      break;

    std::unique_ptr<char, base::AlignedFreeDeleter> deserialized(
        static_cast<char*>(base::AlignedAlloc(
            sizeof(cc::LargestPaintOp), cc::PaintOpBuffer::PaintOpAlign)));
    size_t bytes_read = 0;
    cc::PaintOp* deserialized_op = cc::PaintOp::Deserialize(
        data, size, deserialized.get(), sizeof(cc::LargestPaintOp), &bytes_read,
        deserialize_options);

    if (!deserialized_op)
      break;

    deserialized_op->Raster(canvas, params);

    deserialized_op->DestroyThis();

    if (serialized->skip >= size)
      break;

    size -= bytes_read;
    data += bytes_read;
  }
  return 0;
}