import type { LinkError } from './channelLink';

/** 便捷分享的访客链接:`/s/{id}#k={K}`。分享始终是加密模式,没有所有者链接(完成时已丢弃) */
export interface ParsedShareLink {
  id: string;
  /** 解密密钥 K,只放内存 */
  key: string;
}

export type ShareLinkResult = { ok: true; link: ParsedShareLink } | { ok: false; error: LinkError };

const ID_RE = /^[A-Za-z0-9_-]{22}$/;
const KEY_RE = /^[A-Za-z0-9_-]{43}$/;

export function parseShareLink(input: string): ShareLinkResult {
  let url: URL;
  try {
    url = new URL(input.trim());
  } catch {
    return { ok: false, error: 'bad_url' };
  }
  const m = /^\/s\/([^/]+)\/?$/.exec(url.pathname);
  if (!m?.[1]) return { ok: false, error: 'bad_url' };
  if (!ID_RE.test(m[1])) return { ok: false, error: 'bad_id' };

  const key = new URLSearchParams(url.hash.replace(/^#/, '')).get('k');
  if (key === null || !KEY_RE.test(key)) return { ok: false, error: 'bad_key' };
  return { ok: true, link: { id: m[1], key } };
}