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

function chineseHourToNumber(value) {
  const raw = String(value ?? '').trim();
  if (/^\d{1,2}$/.test(raw)) return Number(raw);
  const map = {
    零: 0,
    一: 1,
    二: 2,
    两: 2,
    三: 3,
    四: 4,
    五: 5,
    六: 6,
    七: 7,
    八: 8,
    九: 9,
    十: 10,
  };
  if (raw === '十') return 10;
  if (raw.startsWith('十')) return 10 + (map[raw.slice(1)] ?? 0);
  if (raw.endsWith('十')) return (map[raw[0]] ?? 0) * 10;
  if (raw.includes('十')) {
    const [tens, ones] = raw.split('十');
    return (map[tens] ?? 1) * 10 + (map[ones] ?? 0);
  }
  return map[raw] ?? null;
}

function parseHourMinute(text) {
  const match = text.match(/(?:早上|上午|清晨|每天早上|每天上午)?([0-9]{1,2}|[零一二两三四五六七八九十]{1,3})(?:点|:|：)(半|[0-9]{1,2}分?)?/);
  if (!match) return null;
  const hour = chineseHourToNumber(match[1]);
  if (hour === null || hour < 0 || hour > 23) return null;
  let minute = 0;
  if (match[2] === '半') minute = 30;
  else if (match[2]) minute = Number(String(match[2]).replace('分', ''));
  if (!Number.isFinite(minute) || minute < 0 || minute > 59) return null;
  return { hour, minute };
}

function extractTodoTitle(text) {
  const original = String(text ?? '').trim();
  if (!original) return null;
  const quoted = original.match(/[「『【（(“"']([^」』】）)”"']{1,80})[」』】）)”"']/);
  if (quoted?.[1]) {
    const title = quoted[1].trim();
    if (title) return title;
  }
  const trailingCommand = original.match(
    /^(.{1,80}?)(?:帮我)?(?:设|设置|设下|记)(?:一个|下一个)?(?:待办|代办|带办|代拜)(?:吧|一下)?$/u,
  );
  if (trailingCommand?.[1]) {
    const title = trailingCommand[1].trim();
    if (title) return title;
  }
  const cleaned = original
    .replace(
      /^.*?(?:不用提醒|先记一下|帮我记一下|帮我记|记一下|添加待办|添加任务|记个待办|记个任务|设置一个待办|设置一个代办|设置一个带办|设置一个代拜|设置下一个代拜|设下一个代拜|帮我设置一个待办|帮我设置一个代办|帮我设置一个带办|帮我设置一个代拜|待办|代办|带办|代拜|任务)(?:[:：,，、\s]+)?/u,
      '',
    )
    .trim();
  return cleaned || null;
}

function wantsDailyTodoDigest(compact) {
  const daily = /每天|每日|天天/.test(compact);
  if (!daily) return false;
  const send = /发|发送|推送|提醒|通知|给我/.test(compact);
  if (!send) return false;
  const digest =
    /(待办|todo|任务).*(记录|列表|清单|安排|摘要|汇总)/.test(compact)
    || /(今天|今日|当天).*(待办|todo|任务)/.test(compact)
    || /(待办|todo|任务).*(今天|今日|当天)/.test(compact)
    || /一天的待办/.test(compact);
  return digest;
}

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

  if (wantsDailyTodoDigest(compact)) {
    const time = parseHourMinute(compact);
    if (!time) {
      return {
        action: 'create_daily_todo_digest',
        needsClarification: ['digest_time'],
      };
    }
    return {
      action: 'create_daily_todo_digest',
      hour: time.hour,
      minute: time.minute,
    };
  }

  const wantsBalanceAlert = /(余额|钱包|账户).*(不足|低于|提醒|预警|通知)|余额不足|低余额|余额预警/.test(compact);
  if (wantsBalanceAlert) {
    const thresholdMatch = compact.match(/(?:低于|少于|不足|小于)(\d{1,6})(?:元|块|rmb|人民币|cny)?/i);
    const thresholdYuan = thresholdMatch ? Number(thresholdMatch[1]) : null;
    const thresholdCents = thresholdYuan == null ? null : Math.max(0, Math.round(thresholdYuan * 100));
    return thresholdCents == null
      ? { action: 'create_balance_alert', needsClarification: ['threshold'] }
      : { action: 'create_balance_alert', thresholdCents };
  }

  if (/看看|查看|看下|列出/.test(compact) && /(待办|日程|行程|计划|任务)/.test(compact)) {
    return { action: 'query_schedule' };
  }

  const wantsTodoRecord =
    /(不用提醒|先记一下|帮我记一下|帮我记|记一下|添加待办|添加任务|记个待办|记个任务|设置一个待办|设置一个代办|设置一个带办|设置一个代拜|设置下一个代拜|设下一个代拜|帮我设置一个待办|帮我设置一个代办|帮我设置一个带办|帮我设置一个代拜|待办|代办|带办|代拜|任务)/.test(
      compact,
    );
  if (wantsTodoRecord) {
    const explicitNoReminder = /(不用提醒|不提醒|先记一下)/.test(compact);
    const hasScheduleTime = /(提醒|闹钟|叫我|今天|今晚|明天|后天|早上|上午|中午|下午|晚上|[0-9零一二两三四五六七八九十]{1,3}(点|:|：))/.test(
      compact,
    );
    if (!explicitNoReminder && hasScheduleTime) {
      return { action: 'schedule_agent' };
    }
    const title = extractTodoTitle(text);
    if (!title) {
      return { action: 'create_todo', needsClarification: ['todo_title'] };
    }
    return { action: 'create_todo', title };
  }

  return { action: 'none' };
}

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

export function shouldUseScheduleAssistant(text) {
  const compact = normalizeText(text);
  if (!compact) return false;
  if (isScheduleIntent(parseScheduleIntent(text))) return true;
  const scheduleKeywords = /(提醒|待办|代办|带办|代拜|日程|行程|安排|计划|闹钟)/;
  const timeKeywords = /(今天|今晚|明天|后天|早上|上午|中午|下午|晚上|\d{1,2}[点:：])/;
  return scheduleKeywords.test(compact) && timeKeywords.test(compact);
}