/*
 * Copyright 2026 Rive
 */

#include "rive/decoders/bitmap_decoder.hpp"
#include "astcenc.h"

#include <cstdio>
#include <memory>
#include <vector>

std::unique_ptr<Bitmap> decode_astc_texture(
    const uint8_t* blocks,
    size_t byteCount,
    uint32_t width,
    uint32_t height,
    uint32_t blockWidth,
    uint32_t blockHeight)
{
  astcenc_config config;
  astcenc_error err = astcenc_config_init(
      ASTCENC_PRF_LDR_SRGB,
      blockWidth,
      blockHeight,
      1,
      ASTCENC_PRE_MEDIUM,
      ASTCENC_FLG_DECOMPRESS_ONLY,
      &config);
  if (err != ASTCENC_SUCCESS)
  {
    fprintf(
        stderr,
        "DecodeAstcTexture - astcenc_config_init failed: %s\n",
        astcenc_get_error_string(err));
    return nullptr;
  }

  astcenc_context* ctx = nullptr;
  err = astcenc_context_alloc(&config, 1, &ctx);
  if (err != ASTCENC_SUCCESS)
  {
    fprintf(
        stderr,
        "DecodeAstcTexture - astcenc_context_alloc failed: %s\n",
        astcenc_get_error_string(err));
    return nullptr;
  }

  const size_t pixelCount = static_cast<size_t>(width) * height;
  auto pixels = std::make_unique<uint8_t[]>(pixelCount * 4);

  void* slicePtr = pixels.get();
  astcenc_image outImage;
  outImage.dim_x = width;
  outImage.dim_y = height;
  outImage.dim_z = 1;
  outImage.data_type = ASTCENC_TYPE_U8;
  outImage.data = &slicePtr;

  const astcenc_swizzle swizzle =
      {ASTCENC_SWZ_R, ASTCENC_SWZ_G, ASTCENC_SWZ_B, ASTCENC_SWZ_A};

  err = astcenc_decompress_image(
      ctx,
      blocks,
      byteCount,
      &outImage,
      &swizzle,
      0);
  astcenc_context_free(ctx);

  if (err != ASTCENC_SUCCESS)
  {
    fprintf(
        stderr,
        "DecodeAstcTexture - astcenc_decompress_image failed: %s\n",
        astcenc_get_error_string(err));
    return nullptr;
  }

  const size_t numBytes = static_cast<size_t>(width) * height * 4;
  return std::make_unique<Bitmap>(
      width,
      height,
      numBytes,
      Bitmap::PixelFormat::RGBA,
      std::move(pixels));
}