Function validateAndSanitizeFile

utils.ts:190–231

(
  file: File,
)

};

export const validateAndSanitizeFile = async (
  file: File,
): Promise<File | null> => {
  const {isValid, detectedType} = await verifyFileSignature(file);

  if (!isValid) {
    console.warn(`[Security] Rejected file "${file.name}": Invalid signature.`);
    return null;
  }

  const ext = file.name.split('.').pop()?.toLowerCase() || '';
  const isJpeg = detectedType === 'jpg' && (ext === 'jpg' || ext === 'jpeg');
  const isPng = detectedType === 'png' && ext === 'png';
  const isWebp = detectedType === 'webp' && ext === 'webp';
  const isAvif = detectedType === 'avif' && ext === 'avif';
  const isQoi = detectedType === 'qoi' && ext === 'qoi';
  const isJxl = detectedType === 'jxl' && ext === 'jxl';
  const isGif = detectedType === 'gif' && ext === 'gif';
  const isSvg = detectedType === 'svg' && ext === 'svg';

  if (
    !isJpeg &&
    !isPng &&
    !isWebp &&
    !isAvif &&
    !isQoi &&
    !isJxl &&
    !isGif &&
    !isSvg
  ) {
    console.warn(
      `[Security] Rejected file "${file.name}": Extension (.${ext}) does not match detected content (${detectedType}).`,
    );
    return null;
  }

  if (isSvg) {
    return await sanitizeSvg(file);
  }

  return file;
};