function normalizeText(text) {
  return String(text ?? '').replace(/\s+/g, '').trim();
}

const EXECUTE_VERBS = /(?:做|生成|制作|创建|写|执行|跑|更新|整理|汇总|推送)/u;
const SCHEDULE_MARKERS = /(?:定时(?:自动)?任务|scheduled\s*task|scheduled\s*automation|cron\s*job|recurring\s*task)/iu;
const RECURRENCE_MARKERS = /(?:每天|每日|每周|定时|到点|届时|自动)/u;

function wantsScheduledTaskAutomation(compact) {
  if (SCHEDULE_MARKERS.test(compact)) return true;
  if (!RECURRENCE_MARKERS.test(compact)) return false;
  if (!EXECUTE_VERBS.test(compact)) return false;
  // Pure reminders/digests stay on schedule-assistant or wechat schedule handler.
  if (/(?:提醒我|闹钟|待办记录|待办列表|待办清单|当天待办|一天的待办)/u.test(compact)) return false;
  if (/(?:待办|代办|带办|代拜).{0,8}(?:记录|列表|清单|摘要|汇总)/u.test(compact)) return false;
  return true;
}

export function shouldUseScheduledTaskAutomation(text) {
  const compact = normalizeText(text);
  if (!compact) return false;
  return wantsScheduledTaskAutomation(compact);
}

export function parseScheduledTaskIntent(text) {
  const compact = normalizeText(text);
  if (!compact) return { action: 'none' };

  if (!wantsScheduledTaskAutomation(compact)) {
    return { action: 'none' };
  }

  const wantsCancel = /(?:取消|停止|关闭|删除).{0,12}(?:定时|自动)/u.test(compact)
    || /(?:cancel|stop|disable).{0,12}(?:scheduled|automation|task)/iu.test(compact);
  if (wantsCancel) {
    return { action: 'cancel_scheduled_task' };
  }

  const wantsList = /(?:查看|看看|列出|我的).{0,12}(?:定时|自动).{0,12}(?:任务|自动化)/u.test(compact)
    || /(?:list|show).{0,12}(?:scheduled|automation).{0,12}tasks/iu.test(compact);
  if (wantsList) {
    return { action: 'list_scheduled_tasks' };
  }

  const recurrence = /(?:一次|单次|仅一次|once)/iu.test(compact)
    ? 'once'
    : /(?:每周|weekly)/iu.test(compact)
      ? 'weekly'
      : /(?:每天|每日|daily)/u.test(compact)
        ? 'daily'
        : null;

  const hasTaskSpec = EXECUTE_VERBS.test(compact)
    && !/^(?:帮我)?(?:设|设置|创建|添加)(?:一个|个)?定时(?:自动)?任务/u.test(String(text ?? '').trim());

  const needsClarification = [];
  if (!recurrence && !/(?:明天|后天|今天|今晚|\d{1,2}[点:：]|[零一二两三四五六七八九十]{1,3}点)/u.test(compact)) {
    needsClarification.push('schedule');
  }
  if (!hasTaskSpec) {
    needsClarification.push('task_spec');
  }

  if (needsClarification.length > 0) {
    return {
      action: 'create_scheduled_task',
      needsClarification,
      recurrence: recurrence ?? 'daily',
    };
  }

  return {
    action: 'create_scheduled_task',
    recurrence: recurrence ?? 'daily',
  };
}

export function isScheduledTaskIntent(intent) {
  return intent?.action && intent.action !== 'none';
}