import {
  GROUP_ORDER,
  aggregateReportRecords,
  extractFillMonth,
  extractPeriod,
  formatDateTime,
  getAuditTime,
  getFillTime,
  getRejectReason,
  normalizeGroupName,
} from '@/utils/aggregateReportRecords';
import { NOTIFY_TZLX } from '@/utils/notificationFields';
import { buildManageRoute } from '@/utils/manageRoutes';

const pad2 = (n) => String(n).padStart(2, '0');

const getCurrentPeriod = () => {
  const now = new Date();
  return `${now.getFullYear()}-${pad2(now.getMonth() + 1)}`;
};

const getPreviousPeriod = (period) => {
  const [year, month] = period.split('-').map(Number);
  const prevMonth = month === 1 ? 12 : month - 1;
  const prevYear = month === 1 ? year - 1 : year;
  return `${prevYear}-${pad2(prevMonth)}`;
};

/** 账期截止：次月 1 日 23:59:59 */
const getPeriodDeadlineDate = (period) => {
  const [year, month] = period.split('-').map(Number);
  const nextMonth = month === 12 ? 1 : month + 1;
  const nextYear = month === 12 ? year + 1 : year;
  return new Date(nextYear, nextMonth - 1, 1, 23, 59, 59);
};

const toTimestamp = (val) => {
  if (val == null || val === '') return 0;
  const n = Number(val);
  if (Number.isFinite(n) && n > 1e11) return n;
  const d = new Date(val);
  return Number.isNaN(d.getTime()) ? 0 : d.getTime();
};

const matchesGroupPeriod = (item, group, period) => {
  const g = normalizeGroupName(item.c_ssqpjt);
  if (g !== group) return false;
  const fillMonth = extractFillMonth(item);
  if (fillMonth) return fillMonth === period;
  return extractPeriod(item, period) === period;
};

const groupHasAnySubmission = (lists, group, period) =>
  lists.some((list) => list.some((item) => matchesGroupPeriod(item, group, period)));

const groupHasApproved = (approvedList, group, period) =>
  approvedList.some((item) => matchesGroupPeriod(item, group, period));

const groupHasRejected = (rejectedList, group, period) =>
  rejectedList.some((item) => matchesGroupPeriod(item, group, period));

const buildRoute = (tab, query = {}) => buildManageRoute({ tab, ...query });

const notifyYwid = (prefix, period, group, suffix = '') =>
  suffix ? `${prefix}:${period}:${group}:${suffix}` : `${prefix}:${period}:${group}`;

/** 月报聚合记录唯一 ywid（账期 + 青浦集团 + 所属集团，避免同集团多条记录互相覆盖） */
const notifyAggregateYwid = (prefix, record) => {
  const qingpuGroup = (record.qingpuGroup ?? '').trim() || 'unknown';
  const groupName = (record.group ?? '').trim() || qingpuGroup;
  return `${prefix}:${record.period}:${qingpuGroup}:${groupName}`;
};

/** 通知列表过滤、展示用青浦集团 */
const notifyDisplayGroup = (record) => record.qingpuGroup || record.group;

/** 截止前剩余天数 → c_tbtx（1=7天，2=3天，3=1天） */
const getReminderTbtx = (daysLeft) => {
  if (daysLeft <= 0) return 0;
  if (daysLeft <= 1) return 3;
  if (daysLeft <= 3) return 2;
  if (daysLeft <= 7) return 1;
  return 0;
};

const reminderTitle = (period, group, daysLeft) => {
  const label = daysLeft <= 1 ? '1 天' : `${daysLeft} 天`;
  return `${period} 月报截止倒计时 ${label}（${group}）`;
};

/**
 * 生成当前时刻所有适用的通知（幂等，同 c_ywid 不会重复入库）
 */
export const buildNotifications = ({
  pendingList = [],
  approvedList = [],
  rejectedList = [],
} = {}, {
  currentGroup = '',
} = {}) => {
  const notifications = [];
  const now = Date.now();
  const currentPeriod = getCurrentPeriod();
  const deadline = getPeriodDeadlineDate(currentPeriod);
  const daysLeft = Math.ceil((deadline.getTime() - now) / (86400000));
  const reminderTbtx = getReminderTbtx(daysLeft);

  // ── 待审核 ────────────────────────────────────────────────
  aggregateReportRecords(pendingList, { fallbackPeriod: currentPeriod }).forEach((record) => {
    const group = notifyDisplayGroup(record);
    if (currentGroup && group !== currentGroup) return;

    const latest = record.items?.reduce((best, item) => {
      const t = toTimestamp(getFillTime(item));
      return t >= toTimestamp(getFillTime(best)) ? item : best;
    }, record.items?.[0]);
    const title = `${group} ${record.period} 资产月报（${record.count} 条）待审核`;

    notifications.push({
      ywid: notifyAggregateYwid('pending', record),
      time: record.submittedAt,
      type: '待审核',
      title,
      content: title,
      timestamp: toTimestamp(getFillTime(latest)),
      group,
      tzlx: NOTIFY_TZLX.PENDING,
      tbtx: 0,
      shjg: 0,
      route: buildRoute('audit', {
        sub: 'pending',
        group: record.qingpuGroup || group,
        period: record.period,
      }),
    });
  });

  // ── 已通过 ────────────────────────────────────────────────
  aggregateReportRecords(approvedList, { fallbackPeriod: currentPeriod }).forEach((record) => {
    const group = notifyDisplayGroup(record);
    if (currentGroup && group !== currentGroup) return;

    const latest = record.items?.reduce((best, item) => {
      const t = toTimestamp(getAuditTime(item));
      return t >= toTimestamp(getAuditTime(best)) ? item : best;
    }, record.items?.[0]);
    const title = `${record.period} 月报已通过（${record.group}，${record.count} 条）`;

    notifications.push({
      ywid: notifyAggregateYwid('approved', record),
      time: formatDateTime(getAuditTime(latest)),
      type: '审核结果',
      title,
      content: title,
      timestamp: toTimestamp(getAuditTime(latest)),
      group,
      tzlx: NOTIFY_TZLX.AUDIT_RESULT,
      tbtx: 0,
      shjg: 1,
      route: buildRoute('archive', {
        sub: 'history',
        group: record.qingpuGroup || group,
        period: record.period,
        status: '已通过',
      }),
    });
  });

  // ── 已驳回 ────────────────────────────────────────────────
  aggregateReportRecords(rejectedList, { fallbackPeriod: currentPeriod }).forEach((record) => {
    const group = notifyDisplayGroup(record);
    if (currentGroup && group !== currentGroup) return;

    const latest = record.items?.reduce((best, item) => {
      const t = toTimestamp(getAuditTime(item));
      return t >= toTimestamp(getAuditTime(best)) ? item : best;
    }, record.items?.[0]);
    const reason = getRejectReason(latest);
    const title = `${record.period} 月报已被驳回（${record.group}）${reason ? `：${reason}` : ''}`;

    notifications.push({
      ywid: notifyAggregateYwid('rejected', record),
      time: formatDateTime(getAuditTime(latest)),
      type: '审核结果',
      title,
      content: title,
      timestamp: toTimestamp(getAuditTime(latest)),
      group,
      tzlx: NOTIFY_TZLX.AUDIT_RESULT,
      tbtx: 0,
      shjg: 0,
      route: buildRoute('archive', {
        sub: 'history',
        group: record.qingpuGroup || group,
        period: record.period,
        status: '已驳回',
      }),
    });
  });

  // ── 填报提醒（截止前 7/3/1 天，尚未提交的集团）────────────
  if (reminderTbtx > 0) {
    const allLists = [pendingList, approvedList, rejectedList];
    GROUP_ORDER.forEach((group) => {
      if (currentGroup && group !== currentGroup) return;
      if (groupHasAnySubmission(allLists, group, currentPeriod)) return;

      const title = reminderTitle(currentPeriod, group, daysLeft);
      notifications.push({
        ywid: notifyYwid('reminder', currentPeriod, group, String(reminderTbtx)),
        time: formatDateTime(now),
        type: '填报提醒',
        title,
        content: title,
        timestamp: now,
        group,
        tzlx: NOTIFY_TZLX.REMINDER,
        tbtx: reminderTbtx,
        shjg: 0,
        route: buildRoute('archive'),
      });
    });
  }

  // ── 逾期催办 ──────────────────────────────────────────────
  const prevPeriod = getPreviousPeriod(currentPeriod);
  const prevDeadline = getPeriodDeadlineDate(prevPeriod);
  if (now > prevDeadline.getTime()) {
    GROUP_ORDER.forEach((group) => {
      if (currentGroup && group !== currentGroup) return;

      if (groupHasApproved(approvedList, group, prevPeriod)) return;

      const rejected = groupHasRejected(rejectedList, group, prevPeriod);
      const hasAny = groupHasAnySubmission(
        [pendingList, approvedList, rejectedList],
        group,
        prevPeriod
      );

      if (!hasAny) {
        const title = `${prevPeriod} 月报已逾期，请补报（${group}）`;
        notifications.push({
          ywid: notifyYwid('overdue', prevPeriod, group),
          time: formatDateTime(prevDeadline),
          type: '逾期催办',
          title,
          content: title,
          timestamp: prevDeadline.getTime(),
          group,
          tzlx: NOTIFY_TZLX.OVERDUE,
          tbtx: 0,
          shjg: 0,
          route: buildRoute('archive'),
        });
        return;
      }

      if (rejected) {
        const title = `${prevPeriod} 月报被驳回且未重报，请尽快处理（${group}）`;
        notifications.push({
          ywid: notifyYwid('overdue-reject', prevPeriod, group),
          time: formatDateTime(now),
          type: '逾期催办',
          title,
          content: title,
          timestamp: now,
          group,
          tzlx: NOTIFY_TZLX.OVERDUE,
          tbtx: 0,
          shjg: 0,
          route: buildRoute('archive', { sub: 'history', group, period: prevPeriod, status: '已驳回' }),
        });
      }
    });
  }

  // ── 租约到期/预警 ─────────────────────────────────────────
  const expiryItems = approvedList
    .filter((item) => item.status === 'red' || item.status === 'orange')
    .slice(0, 8);

  expiryItems.forEach((item) => {
    const label = item.c_bh || item.c_qymc || '资产';
    const withinOneMonth = item.status === 'red';
    const group = normalizeGroupName(item.c_ssqpjt) || '未知';
    if (currentGroup && group !== currentGroup) return;

    const title = `${label} 租约${withinOneMonth ? '将于一个月内到期' : '将于三个月内到期'}，请关注`;
    notifications.push({
      ywid: `expiry:${item.id}`,
      time: formatDateTime(item.update_time || now),
      type: withinOneMonth ? '租约到期' : '租约预警',
      title,
      content: title,
      timestamp: toTimestamp(item.update_time || now),
      group,
      tzlx: withinOneMonth ? NOTIFY_TZLX.LEASE_EXPIRY : NOTIFY_TZLX.LEASE_WARNING,
      tbtx: 0,
      shjg: 0,
      route: buildRoute('assets'),
    });
  });

  return notifications.sort((a, b) => b.timestamp - a.timestamp);
};