// Copyright 2024 Google Inc.

//

// Licensed under the Apache License, Version 2.0 (the "License");

// you may not use this file except in compliance with the License.

// You may obtain a copy of the License at

//

//      http://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing, software

// distributed under the License is distributed on an "AS IS" BASIS,

// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

// See the License for the specific language governing permissions and

// limitations under the License.

//

////////////////////////////////////////////////////////////////////////////////

#include <cstddef>

#include <cstdint>

#include <cstdlib>

#include <iostream>

#include <memory>

#include <string>

#include <string_view>

#include "imageio/image_dec.h"

#include "src/dsp/cpu.h"

#include "tests/fuzzer/fuzz_utils.h"

#include "webp/decode.h"

#include "webp/encode.h"

#include "webp/types.h"

namespace {

const VP8CPUInfo default_VP8GetCPUInfo = fuzz_utils::VP8GetCPUInfo;

void EncTestImpl(WebPPicture& pic, uint32_t optimization_index, bool use_argb,

                 WebPConfig config,

                 const fuzz_utils::CropOrScaleParams& crop_or_scale_params) {

  fuzz_utils::SetOptimization(default_VP8GetCPUInfo, optimization_index);

  // Crop and scale.

  if (!CropOrScale(&pic, crop_or_scale_params)) {

    const WebPEncodingError error_code = pic.error_code;

    if (error_code == VP8_ENC_ERROR_OUT_OF_MEMORY) return;

    std::cerr << "CropOrScale failed. Error code: " << error_code << "\n";

    std::abort();

  }

  // Skip the cruncher except on small images, it's likely to timeout.

  if (config.lossless && config.quality == 100. && config.method == 6 &&

      pic.width * pic.height >= 10000) {

    config.lossless = 0;

  }

  // Encode.

  WebPMemoryWriter memory_writer;

  WebPMemoryWriterInit(&memory_writer);

  pic.writer = WebPMemoryWrite;

  pic.custom_ptr = &memory_writer;

  if (!WebPEncode(&config, &pic)) {

    const WebPEncodingError error_code = pic.error_code;

    WebPMemoryWriterClear(&memory_writer);

    if (error_code == VP8_ENC_ERROR_OUT_OF_MEMORY) return;

    std::cerr << "WebPEncode failed. Error code: " << error_code << "\n";

    std::abort();

  }

  // Try decoding the result.

  int w, h;

  const uint8_t* const out_data = memory_writer.mem;

  const size_t out_size = memory_writer.size;

  uint8_t* const rgba = WebPDecodeBGRA(out_data, out_size, &w, &h);

  if (rgba == nullptr || w != pic.width || h != pic.height) {

    std::cerr << "WebPDecodeBGRA failed.\n";

    WebPFree(rgba);

    WebPMemoryWriterClear(&memory_writer);

    std::abort();

  }

  // Compare the results if exact encoding.

  if (pic.use_argb && config.lossless && config.near_lossless == 100) {

    const uint32_t* src1 = (const uint32_t*)rgba;

    const uint32_t* src2 = pic.argb;

    for (int y = 0; y < h; ++y, src1 += w, src2 += pic.argb_stride) {

      for (int x = 0; x < w; ++x) {

        uint32_t v1 = src1[x], v2 = src2[x];

        if (!config.exact) {

          if ((v1 & 0xff000000u) == 0 || (v2 & 0xff000000u) == 0) {

            // Only keep alpha for comparison of fully transparent area.

            v1 &= 0xff000000u;

            v2 &= 0xff000000u;

          }

        }

        if (v1 != v2) {

          std::cerr << "Lossless compression failed pixel-exactness.\n";

          WebPFree(rgba);

          WebPMemoryWriterClear(&memory_writer);

          std::abort();

        }

      }

    }

  }

  WebPFree(rgba);

  WebPMemoryWriterClear(&memory_writer);

  WebPPictureFree(&pic);

}

// For open source compatibility, maybe_unused is necessary.

[[maybe_unused]] void EncFileTest(

    std::string_view file, uint32_t optimization_index, bool use_argb,

    WebPConfig config,

    const fuzz_utils::CropOrScaleParams& crop_or_scale_params) {

  // Init the source picture.

  WebPPicture pic;

  if (!WebPPictureInit(&pic)) {

    std::cerr << "WebPPictureInit failed.\n";

    std::abort();

  }

  pic.use_argb = use_argb;

  const uint8_t* const file_data =

      reinterpret_cast<const uint8_t*>(file.data());

  if (fuzz_utils::IsImageTooBig(file_data, file.size())) return;

  WebPImageReader reader = WebPGuessImageReader(file_data, file.size());

  if (!reader(file_data, file.size(), &pic, 1, NULL)) return;

  EncTestImpl(pic, optimization_index, use_argb, config, crop_or_scale_params);

}

void EncArbitraryTest(

    fuzz_utils::WebPPictureCpp pic_cpp, uint32_t optimization_index,

    bool use_argb, WebPConfig config,

    const fuzz_utils::CropOrScaleParams& crop_or_scale_params) {

  WebPPicture& pic = pic_cpp.ref();

  EncTestImpl(pic, optimization_index, use_argb, config, crop_or_scale_params);

}

}  // namespace

FUZZ_TEST(Enc, EncArbitraryTest)

    .WithDomains(fuzz_utils::ArbitraryWebPPicture(),

                 /*optimization_index=*/

                 fuzztest::InRange<uint32_t>(0,

                                             fuzz_utils::kMaxOptimizationIndex),

                 /*use_argb=*/fuzztest::Arbitrary<bool>(),

                 fuzz_utils::ArbitraryWebPConfig(),

                 fuzz_utils::ArbitraryCropOrScaleParams());