// SPDX-License-Identifier: GPL-2.0-or-later

#include "cr2header_int.hpp"

#include "tags.hpp"

#include "tiffimage_int.hpp"

#include "types.hpp"

#include <algorithm>

#include <cstdint>

#include <cstring>

namespace Exiv2::Internal {

Cr2Header::Cr2Header(ByteOrder byteOrder) : TiffHeaderBase(42, 16, byteOrder, 0x00000010) {

}

bool Cr2Header::read(const byte* pData, size_t size) {

  if (!pData || size < 16) {

    return false;

  }

  if (pData[0] == 'I' && pData[0] == pData[1]) {

    setByteOrder(littleEndian);

  } else if (pData[0] == 'M' && pData[0] == pData[1]) {

    setByteOrder(bigEndian);

  } else {

    return false;

  }

  if (tag() != getUShort(pData + 2, byteOrder()))

    return false;

  setOffset(getULong(pData + 4, byteOrder()));

  if (0 != memcmp(pData + 8, cr2sig_.data(), 4))

    return false;

  offset2_ = getULong(pData + 12, byteOrder());

  return true;

}

DataBuf Cr2Header::write() const {

  DataBuf buf(16);

  switch (byteOrder()) {

    case littleEndian:

      buf.write_uint8(0, 'I');

      break;

    case bigEndian:

      buf.write_uint8(0, 'M');

      break;

    default:

      break;

  }

  buf.write_uint8(1, buf.read_uint8(0));

  buf.write_uint16(2, tag(), byteOrder());

  buf.write_uint32(4, 0x00000010, byteOrder());

  std::copy(cr2sig_.begin(), cr2sig_.end(), buf.begin() + 8);

  // Write a dummy value for the RAW IFD offset. The offset-writer is used to set this offset in a second pass.

  buf.write_uint32(12, 0x00000000, byteOrder());

  return buf;

}  // Cr2Header::write

bool Cr2Header::isImageTag(uint16_t tag, IfdId group, const PrimaryGroups& /*pPrimaryGroups*/) const {

  // CR2 image tags are all IFD2 and IFD3 tags

  if (group == IfdId::ifd2Id || group == IfdId::ifd3Id)

    return true;

  // ...and any (IFD0) tag that is in the TIFF image tags list

  return isTiffImageTag(tag, group);

}

}  // namespace Exiv2::Internal