/*

 * HEIF codec.

 * Copyright (c) 2024 Dirk Farin <dirk.farin@gmail.com>

 *

 * This file is part of libheif.

 *

 * libheif is free software: you can redistribute it and/or modify

 * it under the terms of the GNU Lesser General Public License as

 * published by the Free Software Foundation, either version 3 of

 * the License, or (at your option) any later version.

 *

 * libheif is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public License

 * along with libheif.  If not, see <http://www.gnu.org/licenses/>.

 */

#include "iden.h"

#include "context.h"

#include "file.h"

ImageItem_iden::ImageItem_iden(HeifContext* ctx)

    : ImageItem(ctx)

{

}

ImageItem_iden::ImageItem_iden(HeifContext* ctx, heif_item_id id)

    : ImageItem(ctx, id)

{

}

Result<std::shared_ptr<HeifPixelImage>> ImageItem_iden::decode_compressed_image(const heif_decoding_options& options,

                                                                                bool decode_tile_only, uint32_t tile_x0, uint32_t tile_y0,

                                                                                std::set<heif_item_id> processed_ids) const

{

  if (processed_ids.contains(get_id())) {

    return Error{heif_error_Invalid_input,

                 heif_suberror_Unspecified,

                 "'iref' has cyclic references"};

  }

  processed_ids.insert(get_id());

  std::shared_ptr<HeifPixelImage> img;

  // find the ID of the image this image is derived from

  auto iref_box = get_file()->get_iref_box();

  if (!iref_box) {

    return Error(heif_error_Invalid_input,

                 heif_suberror_No_iref_box,

                 "No iref box available, but needed for iden image");

  }

  std::vector<heif_item_id> image_references = iref_box->get_references(get_id(), fourcc("dimg"));

  if (image_references.size() > 1) {

    return Error(heif_error_Invalid_input,

                 heif_suberror_Unspecified,

                 "'iden' image with more than one reference image");

  }

  if (image_references.empty()) {

    return Error(heif_error_Invalid_input,

                 heif_suberror_Unspecified,

                 "'iden' image without 'dimg' reference");

  }

  heif_item_id reference_image_id = image_references[0];

  if (reference_image_id == get_id()) {

    return Error(heif_error_Invalid_input,

                 heif_suberror_Unspecified,

                 "'iden' image referring to itself");

  }

  std::shared_ptr<const ImageItem> imgitem = get_context()->get_image(reference_image_id, true);

  if (!imgitem) {

    return Error(heif_error_Invalid_input,

                 heif_suberror_Unspecified,

                 "'iden' image references unavailable image");

  }

  if (auto error = imgitem->get_item_error()) {

    return error;

  }

  return imgitem->decode_image(options, decode_tile_only, tile_x0, tile_y0, processed_ids);

}

Error ImageItem_iden::get_coded_image_colorspace(heif_colorspace* out_colorspace, heif_chroma* out_chroma) const

{

  heif_item_id child;

  Error err = get_context()->get_id_of_non_virtual_child_image(get_id(), child);

  if (err) {

    return err;

  }

  auto image = get_context()->get_image(child, true);

  if (!image) {

    return Error{heif_error_Invalid_input,

                 heif_suberror_Nonexisting_item_referenced};

  }

  return image->get_coded_image_colorspace(out_colorspace, out_chroma);

}

int ImageItem_iden::get_luma_bits_per_pixel() const

{

  heif_item_id child;

  Error err = get_context()->get_id_of_non_virtual_child_image(get_id(), child);

  if (err) {

    return -1;

  }

  auto image = get_context()->get_image(child, true);

  if (!image) {

    return -1;

  }

  return image->get_luma_bits_per_pixel();

}

int ImageItem_iden::get_chroma_bits_per_pixel() const

{

  heif_item_id child;

  Error err = get_context()->get_id_of_non_virtual_child_image(get_id(), child);

  if (err) {

    return -1;

  }

  auto image = get_context()->get_image(child, true);

  if (!image) {

    return -1;

  }

  return image->get_chroma_bits_per_pixel();

}

heif_brand2 ImageItem_iden::get_compatible_brand() const

{

  assert(false);

  return 0; // TODO (we never write 'iden' images)

}