/**
 * 空运群出站报文：禁止 stream（企微会加「内容由AI生成」和赞踩）。
 * 只发 markdown，且不带 feedback。
 * 有这次 @ 的 req_id 才走 aibot_respond_msg，群里才会引用原消息。
 */
function pickReplyReqId({ fromCaller, fromChat, lastAny }) {
  const caller = String(fromCaller || "").trim();
  if (caller) {
    return caller;
  }
  const chat = String(fromChat || "").trim();
  if (chat) {
    return chat;
  }
  return String(lastAny || "").trim();
}

function buildGroupMessageFrame({ chatId, content, callbackReqId, reqId }) {
  const text = String(content || "");
  const markdown = { content: text };
  if (callbackReqId) {
    return {
      cmd: "aibot_respond_msg",
      headers: { req_id: callbackReqId },
      body: {
        chatid: chatId,
        chat_type: 2,
        msgtype: "markdown",
        markdown,
      },
    };
  }
  return {
    cmd: "aibot_send_msg",
    headers: { req_id: reqId || "aibot_send_msg" },
    body: {
      chatid: chatId,
      chat_type: 2,
      msgtype: "markdown",
      markdown,
    },
  };
}

module.exports = { buildGroupMessageFrame, pickReplyReqId };