dragonsstash/worker/src/archive/extract-image.ts

import path from "path";

const IMAGE_EXTENSIONS = new Set(["jpg", "jpeg", "png", "webp", "gif", "bmp"]);

/**
 * Check if a file path within an archive is an image.
 */
export function isImageFile(filePath: string): boolean {
  const ext = path.extname(filePath).toLowerCase().slice(1);
  return IMAGE_EXTENSIONS.has(ext);
}

/**
 * Get the MIME type for an image file extension.
 */
export function getImageMimeType(filePath: string): string {
  const ext = path.extname(filePath).toLowerCase().slice(1);
  switch (ext) {
    case "jpg":
    case "jpeg":
      return "image/jpeg";
    case "png":
      return "image/png";
    case "webp":
      return "image/webp";
    case "gif":
      return "image/gif";
    case "bmp":
      return "image/bmp";
    default:
      return "application/octet-stream";
  }
}