export type AuthorDisplay = {
  origin: string;
  username: string;
  name: string | null;
  remote_user?: string | null;
  remote_display_name?: string | null;
  source_base_url: string | null;
};

export function postAuthorLabel(post: AuthorDisplay) {
  const remoteUser = post.remote_user?.split("/").filter(Boolean).at(-1);
  const author = remoteUser || (post.origin === "rss" ? post.name : post.username) || post.name || "unknown";
  if (post.source_base_url) {
    try { return `@${author}@${new URL(post.source_base_url).hostname}`; } catch { /* Keep a readable fallback for legacy malformed URLs. */ }
  }
  return `@${author}`;
}