/**

 * 企微群机器人 markdown/text 消息 @ 成员扩展语法。

 * @see https://developer.work.weixin.qq.com/document/path/91770

 */



/** 生成 `<@userid>` 片段 */

export function formatWecomAtMention(wecomUserId?: string | null): string {

  const uid = (wecomUserId || '').trim();

  return uid ? `<@${uid}>` : '';

}



/** 若正文未含 `<@userid>` 则前缀追加 */

export function applyWecomAtMentionInContent(content: string, wecomUserId?: string | null): string {

  const text = (content || '').trim();

  const atTag = formatWecomAtMention(wecomUserId);

  if (!atTag) return text;

  if (!text) return atTag;

  if (text.includes(atTag)) return text;

  return `${atTag} ${text}`;

}