/**
 * Guess a Content-Type from a filename based on extension.
 * This is used for inline media preview in the UI (images, PDFs, etc.).
 * Defaults to application/octet-stream when unknown.
 */
export function getContentTypeFromName(name: string): string {
  const ext = (name.split(".").pop() || "").toLowerCase();
  switch (ext) {
    case "png":
      return "image/png";
    case "jpg":
    case "jpeg":
      return "image/jpeg";
    case "gif":
      return "image/gif";
    case "webp":
      return "image/webp";
    case "bmp":
      return "image/bmp";
    case "ico":
      return "image/x-icon";
    case "svg":
      return "image/svg+xml";
    case "pdf":
      return "application/pdf";
    case "txt":
      return "text/plain; charset=utf-8";
    default:
      return "application/octet-stream";
  }
}