import { useCallback, useEffect, useMemo, useState } from 'react';
import { Link, useNavigate } from 'react-router-dom';
import type { PartnerAssocStats, PartnerLeaderboardEntry, PartnerSettlementPreviewDto } from '@dukang/shared-types';
import PullToRefresh from '@dukang/shared-ui/PullToRefresh';
import { usePartnerPageView } from '../lib/usePageView';
import { isLoggedIn, request } from '../lib/api';
import { fetchPartnerLeaderboard } from '../lib/leaderboard';
import { formatBillPeriod, formatIssueLabel } from '../lib/settlement';
import {
  canAccessPartnerDashboard,
  canAccessPartnerOrders,
  canAccessPartnerStores,
  getPartnerNavKind,
  hasWarehouseAccess,
} from '../lib/partnerAccess';
import { usePartnerSession } from '../contexts/PartnerSessionContext';

function fmtMoney(n: number) {
  return n.toLocaleString('zh-CN', { minimumFractionDigits: 2, maximumFractionDigits: 2 });
}

const LEADERBOARD_PREVIEW_LIMIT = 3;

function OrderSummarySection({
  title,
  todayCount,
  pendingShip,
  shipping,
  completed,
  ordersLink = '/orders',
}: {
  title?: string;
  todayCount: number;
  pendingShip: number;
  shipping: number;
  completed: number;
  ordersLink?: string;
}) {
  return (
    <section>
      <div className="partner-order-summary-header">
        <h2 className="headline-md">{title || `今日订单 ${todayCount}`}</h2>
        <Link to={ordersLink} className="label-md text-primary" style={{ display: 'flex', alignItems: 'center', gap: 2 }}>
          查看全部 <span className="material-symbols-outlined" style={{ fontSize: 14 }}>chevron_right</span>
        </Link>
      </div>
      <div className="partner-order-stats">
        <div className="partner-order-stat">
          <p className="label-md text-muted" style={{ marginBottom: 4 }}>待发货</p>
          <p className="headline-lg" style={{ fontSize: 24, fontWeight: 600 }}>{pendingShip}</p>
        </div>
        <div className="partner-order-stat partner-order-stat--blue">
          <p className="label-md text-muted" style={{ marginBottom: 4 }}>配送中</p>
          <p className="headline-lg" style={{ fontSize: 24, fontWeight: 600 }}>{shipping}</p>
        </div>
        <div className="partner-order-stat partner-order-stat--green">
          <p className="label-md text-muted" style={{ marginBottom: 4 }}>已完成</p>
          <p className="headline-lg" style={{ fontSize: 24, fontWeight: 600 }}>{completed}</p>
        </div>
      </div>
    </section>
  );
}

function isPendingShip(status: string) {
  const s = status.toUpperCase();
  return s.includes('PENDING') || s === 'PAID' || s === 'PENDING_SHIP';
}

function isShipping(status: string) {
  const s = status.toUpperCase();
  return s.includes('SHIP') || s === 'OUT_WAREHOUSE' || s === 'PENDING_RECEIVE';
}

function isCompleted(status: string) {
  return status.toUpperCase() === 'COMPLETED';
}

function isToday(dateStr: string) {
  const d = new Date(dateStr);
  const now = new Date();
  return d.getFullYear() === now.getFullYear()
    && d.getMonth() === now.getMonth()
    && d.getDate() === now.getDate();
}

function summarizeOrders(orders: Array<Record<string, unknown>>) {
  let pendingShip = 0;
  let shipping = 0;
  let completed = 0;
  let todayCount = 0;
  for (const o of orders) {
    const status = String(o.status || '');
    if (isToday(String(o.createdAt || ''))) todayCount += 1;
    if (isPendingShip(status)) pendingShip += 1;
    else if (isShipping(status)) shipping += 1;
    else if (isCompleted(status)) completed += 1;
  }
  return { pendingShip, shipping, completed, todayCount };
}

function LeaderboardPreview({ entries }: { entries: PartnerLeaderboardEntry[] }) {
  return (
    <section className="partner-bento-card partner-leaderboard-preview">
      <div className="partner-leaderboard-header">
        <h3 className="headline-md" style={{ display: 'flex', alignItems: 'center', gap: 8 }}>
          <span className="material-symbols-outlined text-primary" style={{ fontSize: 20 }}>emoji_events</span>
          团队贡献榜
        </h3>
        <Link to="/leaderboard" className="label-md text-primary" style={{ display: 'flex', alignItems: 'center', gap: 2 }}>
          查看全部 <span className="material-symbols-outlined" style={{ fontSize: 14 }}>chevron_right</span>
        </Link>
      </div>
      {entries.length === 0 ? (
        <p className="label-md text-muted">暂无排行数据</p>
      ) : (
        entries.map((entry) => (
          <div key={entry.accountId} className="partner-leaderboard-row partner-leaderboard-row--compact">
            <div className={`partner-leaderboard-avatar partner-leaderboard-avatar--rank-${Math.min(entry.rank, 3)}`}>
              <span className="material-symbols-outlined">person</span>
              <span className="partner-leaderboard-avatar-badge">{entry.rank}</span>
            </div>
            <div className="partner-leaderboard-info">
              <p className="body-md" style={{ fontWeight: 600 }}>
                {entry.name}
                <span className="label-md text-muted" style={{ marginLeft: 4 }}>({entry.roleLabel})</span>
              </p>
              <p className="label-md text-muted">累计拓店: {entry.totalStores} 间</p>
            </div>
            <div className="partner-leaderboard-stat">
              {entry.periodStores > 0 ? (
                <>
                  <p className="headline-md text-primary">{entry.periodStores} 间</p>
                  <p className="label-md text-muted">本月新增</p>
                </>
              ) : null}
            </div>
          </div>
        ))
      )}
    </section>
  );
}

export default function HomePage() {
  usePartnerPageView('partner_home_view');
  const navigate = useNavigate();
  const { account } = usePartnerSession();
  const navKind = getPartnerNavKind(account);
  const isPrimary = navKind === 'primary';
  const isWarehouse = navKind === 'warehouse_staff';
  const warehouseOk = hasWarehouseAccess(account);
  const canOrders = canAccessPartnerOrders(account) && warehouseOk && (isPrimary || isWarehouse);
  const canDashboard = canAccessPartnerDashboard(account) && !isWarehouse;
  const canStores = canAccessPartnerStores(account) && !isWarehouse;

  const [dash, setDash] = useState<Record<string, unknown> | null>(null);
  const [stores, setStores] = useState<Array<Record<string, unknown>>>([]);
  const [orders, setOrders] = useState<Array<Record<string, unknown>>>([]);
  const [leaderboardEntries, setLeaderboardEntries] = useState<PartnerLeaderboardEntry[]>([]);
  const [assocStats, setAssocStats] = useState<PartnerAssocStats | null>(null);
  const [preview, setPreview] = useState<PartnerSettlementPreviewDto | null>(null);

  useEffect(() => {
    document.title = '工作台';
  }, []);

  const loadHome = useCallback(() => {
    if (!isLoggedIn()) {
      navigate('/login');
      return Promise.resolve();
    }
    if (!account) return Promise.resolve();

    const tasks: Promise<unknown>[] = [];

    if (canOrders) {
      tasks.push(
        request<{ list: Array<Record<string, unknown>> }>('PARTNER_H5', '/partner/orders', { silent: true })
          .then((data) => setOrders(Array.isArray(data.list) ? data.list : []))
          .catch(() => setOrders([])),
      );
    } else {
      setOrders([]);
    }

    if (canDashboard) {
      tasks.push(
        request<Record<string, unknown>>('PARTNER_H5', '/partner/dashboard', { silent: true })
          .then(setDash)
          .catch(() => setDash(null)),
      );
    } else {
      setDash(null);
    }

    if (canStores) {
      tasks.push(
        request<Array<Record<string, unknown>>>('PARTNER_H5', '/partner/stores', { silent: true })
          .then((data) => setStores(Array.isArray(data) ? data : []))
          .catch(() => setStores([])),
      );
    } else {
      setStores([]);
    }

    if (isPrimary) {
      tasks.push(
        request<PartnerAssocStats>('PARTNER_H5', '/partner/assoc/stats', { silent: true })
          .then(setAssocStats)
          .catch(() => setAssocStats(null)),
        request<PartnerSettlementPreviewDto>('PARTNER_H5', '/partner/settlement/preview', { silent: true })
          .then(setPreview)
          .catch(() => setPreview(null)),
      );
    } else {
      setAssocStats(null);
      setPreview(null);
    }

    tasks.push(
      fetchPartnerLeaderboard('month')
        .then((data) => {
          setLeaderboardEntries(data.list.slice(0, LEADERBOARD_PREVIEW_LIMIT));
        })
        .catch(() => {
          setLeaderboardEntries([]);
        }),
    );

    return Promise.all(tasks).then(() => undefined);
  }, [navigate, account, canOrders, canDashboard, canStores, isPrimary]);

  useEffect(() => {
    void loadHome();
  }, [loadHome]);

  const storeCount = Number(dash?.storeCount || stores.length || 0);
  const orderStats = useMemo(() => summarizeOrders(orders), [orders]);
  const pendingAuditCount = Number(dash?.pendingAuditCount || 0);
  const activeStores = stores.filter((s) => String(s.status).toUpperCase() === 'OPEN').length;
  const abnormalStores = Math.max(0, storeCount - activeStores);
  const monthNew = stores.filter((s) => {
    const created = new Date(String(s.createdAt || ''));
    const now = new Date();
    return created.getMonth() === now.getMonth() && created.getFullYear() === now.getFullYear();
  }).length;
  const lastMonthNew = stores.filter((s) => {
    const created = new Date(String(s.createdAt || ''));
    const now = new Date();
    const last = new Date(now.getFullYear(), now.getMonth() - 1, 1);
    return created.getMonth() === last.getMonth() && created.getFullYear() === last.getFullYear();
  }).length;
  const monthGrowthPct = lastMonthNew > 0
    ? Math.round(((monthNew - lastMonthNew) / lastMonthNew) * 100)
    : (monthNew > 0 ? 100 : 0);

  return (
    <PullToRefresh onRefresh={loadHome} className="page partner-home partner-home--flush-top">
      <main className="partner-home-body">
        {isPrimary && (
          <>
            <section className="partner-revenue-card">
              <p className="partner-revenue-label">预付款金额 (CNY)</p>
              <div className="partner-revenue-amount">{fmtMoney(preview?.prepaymentAmount ?? 0)}</div>
              <p className="partner-revenue-label" style={{ marginTop: 8, opacity: 0.85, lineHeight: 1.5 }}>
                账期 {formatBillPeriod(preview?.periodStart, preview?.periodEnd)} · {formatIssueLabel(preview)}
              </p>
              <p className="partner-revenue-label" style={{ marginTop: 6, opacity: 0.75 }}>
                本周酒单与核销预估佣金，实际以账单为准
              </p>
            </section>
            <section className="partner-bento-card" style={{ marginBottom: 16 }}>
              <div className="partner-quick-actions">
                <Link to="/proxy-order" className="partner-quick-action">
                  <div className="partner-quick-action-icon partner-quick-action-icon--red">
                    <span className="material-symbols-outlined">shopping_cart_checkout</span>
                  </div>
                  <span className="partner-quick-action-label">代下单</span>
                </Link>
                <Link to="/stores/new" className="partner-quick-action">
                  <div className="partner-quick-action-icon partner-quick-action-icon--red">
                    <span className="material-symbols-outlined">add_business</span>
                  </div>
                  <span className="partner-quick-action-label">录入新店</span>
                </Link>
                <Link to="/center/settlement" className="partner-quick-action">
                  <div className="partner-quick-action-icon partner-quick-action-icon--green">
                    <span className="material-symbols-outlined">account_balance</span>
                  </div>
                  <span className="partner-quick-action-label">财务对账</span>
                </Link>
                <Link to="/reports/weekly" className="partner-quick-action">
                  <div className="partner-quick-action-icon partner-quick-action-icon--blue">
                    <span className="material-symbols-outlined">monitoring</span>
                  </div>
                  <span className="partner-quick-action-label">数据周报</span>
                </Link>
              </div>
            </section>
          </>
        )}

        {isPrimary && (
          <>
            <Link to="/users" className="partner-bento-card" style={{ display: 'block', marginBottom: 16, color: 'inherit', textDecoration: 'none' }}>
              <div className="partner-bento-header">
                <h2 className="headline-md">关联用户</h2>
                <span className="amount-lg" style={{ fontSize: 24 }}>{assocStats?.userTotal ?? 0}</span>
              </div>
              <div className="partner-store-stats">
                <div className="partner-store-stat">
                  <div>
                    <p className="label-md text-muted">本日</p>
                    <p className="headline-md">{assocStats?.userToday ?? 0}</p>
                  </div>
                </div>
                <div className="partner-store-stat">
                  <div>
                    <p className="label-md text-muted">本月</p>
                    <p className="headline-md">{assocStats?.userMonth ?? 0}</p>
                  </div>
                </div>
              </div>
            </Link>
            <Link to="/users/orders" className="partner-bento-card" style={{ display: 'block', marginBottom: 16, color: 'inherit', textDecoration: 'none' }}>
              <div className="partner-bento-header">
                <h2 className="headline-md">关联用户订单</h2>
                <span className="amount-lg" style={{ fontSize: 24 }}>{assocStats?.orderTotal ?? 0}</span>
              </div>
              <div className="partner-store-stats">
                <div className="partner-store-stat">
                  <div>
                    <p className="label-md text-muted">本日</p>
                    <p className="headline-md">{assocStats?.orderToday ?? 0}</p>
                  </div>
                </div>
                <div className="partner-store-stat">
                  <div>
                    <p className="label-md text-muted">本月</p>
                    <p className="headline-md">{assocStats?.orderMonth ?? 0}</p>
                  </div>
                </div>
              </div>
            </Link>
          </>
        )}

        {isWarehouse && (
          <p className="headline-md" style={{ marginBottom: 8 }}>订单管理</p>
        )}

        {canOrders && (
          <OrderSummarySection
            title={isWarehouse ? '今日订单' : undefined}
            todayCount={orderStats.todayCount}
            pendingShip={orderStats.pendingShip}
            shipping={orderStats.shipping}
            completed={orderStats.completed}
          />
        )}

        {(isPrimary || isWarehouse) && !warehouseOk && (
          <section className="partner-bento-card" style={{ marginBottom: 16 }}>
            <div className="partner-warehouse-denied">
              <span className="material-symbols-outlined text-primary">warehouse</span>
              <p className="body-md" style={{ fontWeight: 600, marginTop: 8 }}>未配置仓库管理权限</p>
              <p className="label-md text-muted" style={{ marginTop: 4, lineHeight: 1.5 }}>
                购酒订单由总部履约，不会推送到本账号。如需管仓发货，请联系总部配置仓库。
              </p>
            </div>
          </section>
        )}

        {canStores && (
          <>
            <section className="partner-bento-card" style={{ marginBottom: 16 }}>
              <div className="partner-bento-header">
                <h2 className="headline-md">门店总数</h2>
                <span className="amount-lg" style={{ fontSize: 24 }}>{storeCount}</span>
              </div>
              <div className="partner-store-stats">
                <div className="partner-store-stat">
                  <span className="partner-dot partner-dot--green" />
                  <div>
                    <p className="label-md text-muted">正常运营</p>
                    <p className="headline-md">{activeStores}</p>
                  </div>
                </div>
                <div className="partner-store-stat">
                  <span className="partner-dot partner-dot--red" />
                  <div>
                    <p className="label-md text-muted">异常/闭店</p>
                    <p className="headline-md">{abnormalStores}</p>
                  </div>
                </div>
              </div>
            </section>

            <section className="partner-expansion-card">
              <h2 className="headline-md" style={{ marginBottom: 16 }}>拓店情况</h2>
              <div className="partner-expansion-split">
                <div>
                  <p className="label-md text-muted" style={{ marginBottom: 4 }}>本月新增签约</p>
                  <div className="partner-expansion-value-row">
                    <span className="headline-lg" style={{ fontSize: 24 }}>{monthNew}</span>
                    {monthGrowthPct !== 0 && (
                      <span className={`partner-expansion-trend${monthGrowthPct > 0 ? ' partner-expansion-trend--up' : ' partner-expansion-trend--down'}`}>
                        <span className="material-symbols-outlined" style={{ fontSize: 14 }}>
                          {monthGrowthPct > 0 ? 'trending_up' : 'trending_down'}
                        </span>
                        {Math.abs(monthGrowthPct)}%
                      </span>
                    )}
                  </div>
                </div>
                <div>
                  <p className="label-md text-muted" style={{ marginBottom: 4 }}>待审核门店</p>
                  <span className="headline-lg" style={{ fontSize: 24 }}>{pendingAuditCount}</span>
                </div>
              </div>
            </section>
          </>
        )}

        <LeaderboardPreview entries={leaderboardEntries} />
      </main>
    </PullToRefresh>
  );
}