export type WecomCallbackFields = Record<string, string>;

export type WecomCallbackEventResult = {
  recognized: boolean;
  action: string;
  taskId: string;
  btnKey: string;
  operator: string;
};

export function parseWecomCallbackXml(xml: string): WecomCallbackFields {
  const fields: WecomCallbackFields = {};
  const source = String(xml ?? "");
  const pattern =
    /<([A-Za-z][A-Za-z0-9_]*)>(?:<!\[CDATA\[([\s\S]*?)\]\]>|([^<]*))<\/\1>/g;
  let match: RegExpExecArray | null;
  while ((match = pattern.exec(source)) !== null) {
    const tag = match[1];
    const value = match[2] ?? match[3] ?? "";
    if (!(tag in fields)) fields[tag] = value.trim();
  }
  return fields;
}

export function extractWecomEncryptField(body: string): string {
  const fields = parseWecomCallbackXml(body);
  return fields.Encrypt ?? "";
}

export function handleWecomCallbackEvent(
  fields: WecomCallbackFields,
): WecomCallbackEventResult {
  const event = fields.Event ?? "";
  const taskId = fields.TaskId ?? "";
  const btnKey = fields.BtnKey ?? "";
  const operator = fields.FromUserName ?? "";

  if (fields.MsgType === "event" && event === "template_card_event") {
    if (btnKey === "mark_handled") {
      console.info(
        "[KOC LOOP] wecom card ack",
        { taskId, operator },
      );
      return { recognized: true, action: "card_ack", taskId, btnKey, operator };
    }
    return { recognized: true, action: "ignored", taskId, btnKey, operator };
  }

  console.info("[KOC LOOP] wecom callback event ignored", {
    msgType: fields.MsgType ?? "",
    event,
  });
  return { recognized: false, action: "ignored", taskId, btnKey, operator };
}