// Copyright (c) the JPEG XL Project 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 "lib/jxl/enc_external_image.h"

#include <jxl/memory_manager.h>

#include <jxl/types.h>

#include <cstdint>

#include <cstring>

#include <utility>

#include "lib/jxl/base/byte_order.h"

#include "lib/jxl/base/common.h"

#include "lib/jxl/base/compiler_specific.h"

#include "lib/jxl/base/data_parallel.h"

#include "lib/jxl/base/float.h"

#include "lib/jxl/base/printf_macros.h"

#include "lib/jxl/base/span.h"

#include "lib/jxl/base/status.h"

#include "lib/jxl/color_encoding_internal.h"

#include "lib/jxl/image.h"

#include "lib/jxl/image_bundle.h"

#include "lib/jxl/image_ops.h"

namespace jxl {

namespace {

size_t JxlDataTypeBytes(JxlDataType data_type) {

  switch (data_type) {

    case JXL_TYPE_UINT8:

      return 1;

    case JXL_TYPE_UINT16:

      return 2;

    case JXL_TYPE_FLOAT16:

      return 2;

    case JXL_TYPE_FLOAT:

      return 4;

    default:

      return 0;

  }

}

}  // namespace

Status ConvertFromExternalPlaneNoSizeCheck(const uint8_t* data, size_t xsize,

                                           size_t ysize, size_t stride,

                                           size_t bits_per_sample,

                                           JxlPixelFormat format, size_t c,

                                           ThreadPool* pool, ImageF* channel) {

  if (format.data_type == JXL_TYPE_UINT8) {

    JXL_RETURN_IF_ERROR(bits_per_sample > 0 && bits_per_sample <= 8);

  } else if (format.data_type == JXL_TYPE_UINT16) {

    JXL_RETURN_IF_ERROR(bits_per_sample > 8 && bits_per_sample <= 16);

  } else if (format.data_type != JXL_TYPE_FLOAT16 &&

             format.data_type != JXL_TYPE_FLOAT) {

    return JXL_FAILURE("unsupported pixel format data type %d",

                       format.data_type);

  }

  JXL_ENSURE(channel->xsize() == xsize);

  JXL_ENSURE(channel->ysize() == ysize);

  size_t bytes_per_channel = JxlDataTypeBytes(format.data_type);

  size_t bytes_per_pixel = format.num_channels * bytes_per_channel;

  size_t bytes_per_row;

  if (!SafeMul(xsize, bytes_per_pixel, bytes_per_row)) {

    return JXL_FAILURE("Image dimensions are too large");

  }

  JXL_ENSURE(bytes_per_row <= stride);

  size_t pixel_offset = c * bytes_per_channel;

  // Only for uint8/16.

  float scale = 1.0f / ((1ull << bits_per_sample) - 1);

  const bool little_endian =

      format.endianness == JXL_LITTLE_ENDIAN ||

      (format.endianness == JXL_NATIVE_ENDIAN && IsLittleEndian());

  const auto convert_row = [&](const uint32_t task,

                               size_t /*thread*/) -> Status {

    const size_t y = task;

    size_t offset = y * stride + pixel_offset;

    float* JXL_RESTRICT row_out = channel->Row(y);

    const auto save_value = [&](size_t index, float value) {

      row_out[index] = value;

    };

    JXL_RETURN_IF_ERROR(LoadFloatRow(data + offset, xsize, bytes_per_pixel,

                                     format.data_type, little_endian, scale,

                                     save_value));

    return true;

  };

  JXL_RETURN_IF_ERROR(RunOnPool(pool, 0, static_cast<uint32_t>(ysize),

                                ThreadPool::NoInit, convert_row,

                                "ConvertExtraChannel"));

  return true;

}

Status ConvertFromExternal(const uint8_t* data, size_t size, size_t xsize,

                           size_t ysize, size_t bits_per_sample,

                           JxlPixelFormat format, size_t c, ThreadPool* pool,

                           ImageF* channel) {

  size_t bytes_per_channel = JxlDataTypeBytes(format.data_type);

  size_t bytes_per_pixel;

  if (!SafeMul(static_cast<size_t>(format.num_channels), bytes_per_channel,

               bytes_per_pixel)) {

    return JXL_FAILURE("Invalid format");

  }

  size_t last_row_size;

  if (!SafeMul(xsize, bytes_per_pixel, last_row_size)) {

    return JXL_FAILURE("Image dimensions are too large");

  }

  size_t row_size = last_row_size;

  if (!SafeRoundUpTo(row_size, format.align, row_size)) {

    return JXL_FAILURE("Image dimensions are too large");

  }

  if (xsize == 0 || ysize == 0) return JXL_FAILURE("Empty image");

  size_t bytes_to_read;

  if (!SafeMul(row_size, ysize - 1, bytes_to_read) ||

      !SafeAdd(bytes_to_read, last_row_size, bytes_to_read)) {

    return JXL_FAILURE("Image dimensions are too large");

  }

  if (size > 0 && size < bytes_to_read) {

    return JXL_FAILURE("Buffer size is too small, expected: %" PRIuS

                       " got: %" PRIuS " (Image: %" PRIuS "x%" PRIuS

                       "x%u, bytes_per_channel: %" PRIuS ")",

                       bytes_to_read, size, xsize, ysize, format.num_channels,

                       bytes_per_channel);

  }

  // Too large buffer is likely an application bug, so also fail for that.

  // Do allow padding to stride in last row though.

  if (size > row_size * ysize) {

    return JXL_FAILURE("Buffer size is too large");

  }

  return ConvertFromExternalPlaneNoSizeCheck(

      data, xsize, ysize, row_size, bits_per_sample, format, c, pool, channel);

}

Status ConvertFromExternal(Span<const uint8_t> bytes, size_t xsize,

                           size_t ysize, const ColorEncoding& c_current,

                           size_t bits_per_sample, JxlPixelFormat format,

                           ThreadPool* pool, ImageBundle* ib, bool set_alpha) {

  JxlMemoryManager* memory_manager = ib->memory_manager();

  size_t color_channels = c_current.Channels();

  bool has_alpha = format.num_channels == 2 || format.num_channels == 4;

  if (format.num_channels < color_channels) {

    return JXL_FAILURE("Expected %" PRIuS

                       " color channels, received only %u channels",

                       color_channels, format.num_channels);

  }

  JXL_ASSIGN_OR_RETURN(Image3F color,

                       Image3F::Create(memory_manager, xsize, ysize));

  for (size_t c = 0; c < color_channels; ++c) {

    JXL_RETURN_IF_ERROR(ConvertFromExternal(bytes.data(), bytes.size(), xsize,

                                            ysize, bits_per_sample, format, c,

                                            pool, &color.Plane(c)));

  }

  if (color_channels == 1) {

    JXL_RETURN_IF_ERROR(CopyImageTo(color.Plane(0), &color.Plane(1)));

    JXL_RETURN_IF_ERROR(CopyImageTo(color.Plane(0), &color.Plane(2)));

  }

  JXL_RETURN_IF_ERROR(ib->SetFromImage(std::move(color), c_current));

  // Passing an interleaved image with an alpha channel to an image that doesn't

  // have alpha channel just discards the passed alpha channel.

  if (set_alpha) {

    JXL_ASSIGN_OR_RETURN(ImageF alpha,

                         ImageF::Create(memory_manager, xsize, ysize));

    if (has_alpha) {

      JXL_RETURN_IF_ERROR(ConvertFromExternal(

          bytes.data(), bytes.size(), xsize, ysize, bits_per_sample, format,

          format.num_channels - 1, pool, &alpha));

    } else {

      // if alpha is not passed, but it is expected, then assume

      // it is all-opaque

      FillImage(1.0f, &alpha);

    }

    JXL_RETURN_IF_ERROR(ib->SetAlpha(std::move(alpha)));

  }

  return true;

}

Status BufferToImageF(const JxlPixelFormat& pixel_format, size_t xsize,

                      size_t ysize, const void* buffer, size_t size,

                      ThreadPool* pool, ImageF* channel) {

  size_t bitdepth = JxlDataTypeBytes(pixel_format.data_type) * kBitsPerByte;

  return ConvertFromExternal(reinterpret_cast<const uint8_t*>(buffer), size,

                             xsize, ysize, bitdepth, pixel_format, 0, pool,

                             channel);

}

Status BufferToImageBundle(const JxlPixelFormat& pixel_format, uint32_t xsize,

                           uint32_t ysize, const void* buffer, size_t size,

                           jxl::ThreadPool* pool,

                           const jxl::ColorEncoding& c_current,

                           jxl::ImageBundle* ib, bool set_alpha) {

  size_t bitdepth = JxlDataTypeBytes(pixel_format.data_type) * kBitsPerByte;

  JXL_RETURN_IF_ERROR(ConvertFromExternal(

      jxl::Bytes(static_cast<const uint8_t*>(buffer), size), xsize, ysize,

      c_current, bitdepth, pixel_format, pool, ib, set_alpha));

  JXL_RETURN_IF_ERROR(ib->VerifyMetadata());

  return true;

}

}  // namespace jxl