import { useEffect, useState } from 'react';
import { View, Text, Button } from '@tarojs/components';
import Taro, { useRouter } from '@tarojs/taro';
import type { PromoCodeItem, PromoCodeStats } from '@dukang/shared-types';
import HqHeader from '../../components/HqHeader';
import { request, toast } from '../../lib/api';
import { useHqSession } from '../../lib/session';
import { buildPromoQrDataUrl, promoConversion } from '../../lib/promo-qr';
import './index.css';
import './index.css';

type PromoDetail = PromoCodeItem & { stats?: PromoCodeStats };

export default function PromoDetailPage() {
  useHqSession();
  const router = useRouter();
  const id = router.params.id ?? '';
  const [row, setRow] = useState<PromoDetail | null>(null);
  const [loading, setLoading] = useState(true);
  const [updating, setUpdating] = useState(false);
  const [qrUrl, setQrUrl] = useState('');

  useEffect(() => {
    if (!id) return;
    setLoading(true);
    request<PromoDetail>(`/admin/promo-codes/${id}`)
      .then(setRow)
      .catch(() => setRow(null))
      .finally(() => setLoading(false));
  }, [id]);

  useEffect(() => {
    if (!row?.landingUrl) {
      setQrUrl('');
      return;
    }
    void buildPromoQrDataUrl(row.landingUrl).then(setQrUrl).catch(() => setQrUrl(''));
  }, [row?.landingUrl]);

  async function toggleStatus() {
    if (!row) return;
    const next = row.status === 'ACTIVE' ? 'DISABLED' : 'ACTIVE';
    const label = next === 'DISABLED' ? '停用' : '启用';
    const ok = await Taro.showModal({
      title: `确认${label}`,
      content: next === 'DISABLED' ? '停用后扫码将不再追踪数据' : '启用后恢复追踪',
    });
    if (!ok.confirm) return;
    setUpdating(true);
    try {
      const updated = await request<PromoCodeItem>(`/admin/promo-codes/${id}/status`, {
        method: 'PUT',
        data: { status: next },
      });
      setRow((prev) => (prev ? { ...prev, ...updated } : updated));
      toast(`已${label}`, 'success');
    } catch (e) {
      toast(e instanceof Error ? e.message : '操作失败');
    } finally {
      setUpdating(false);
    }
  }

  function copyLink() {
    if (!row?.landingUrl) return;
    Taro.setClipboardData({ data: row.landingUrl }).then(() => toast('推广链接已复制', 'success'));
  }

  function downloadQr() {
    if (!qrUrl) return;
    if (process.env.TARO_ENV === 'h5') {
      const a = document.createElement('a');
      a.href = qrUrl;
      a.download = `promo-${row?.code ?? 'qr'}.png`;
      a.click();
      toast('已开始下载', 'success');
      return;
    }
    Taro.previewImage({ urls: [qrUrl] });
  }

  const stats = row?.stats ?? (row ? {
    scanCount: row.scanCount,
    orderCount: row.orderCount,
    conversionRate: parseFloat(promoConversion(row.scanCount, row.orderCount)) || 0,
  } : null);

  if (loading) {
    return (
      <View className="hq-page promo-page">
        <HqHeader title="推广码详情" back />
        <View className="promo-empty">加载中…</View>
      </View>
    );
  }

  if (!row) {
    return (
      <View className="hq-page promo-page">
        <HqHeader title="推广码详情" back />
        <View className="promo-empty">推广码不存在</View>
      </View>
    );
  }

  return (
    <View className="hq-page promo-page">
      <HqHeader title="推广码详情" back />

      <View className="promo-detail-card">
        <View className="promo-detail-card__qr">
          {qrUrl ? (
            <View className="promo-result__qr" style={{ backgroundImage: `url(${qrUrl})` }} />
          ) : null}
        </View>
        <View className="promo-detail-card__info">
          <Text className="promo-detail-card__name">{row.name}</Text>
          <Text
            className={`promo-card__badge ${
              row.status === 'ACTIVE' ? 'promo-card__badge--active' : 'promo-card__badge--disabled'
            }`}
          >
            {row.status === 'ACTIVE' ? '运行中' : '已停用'}
          </Text>
          <Text className="promo-detail-card__meta">码值 {row.code}</Text>
        </View>
      </View>

      {stats && (
        <View className="promo-stats-grid">
          <View className="promo-stat-card">
            <Text className="material-symbols-outlined promo-stat-card__icon">visibility</Text>
            <Text className="promo-stat-card__label">扫码UV</Text>
            <Text className="promo-stat-card__value">{stats.scanCount}</Text>
          </View>
          <View className="promo-stat-card">
            <Text className="material-symbols-outlined promo-stat-card__icon">shopping_cart</Text>
            <Text className="promo-stat-card__label">下单数</Text>
            <Text className="promo-stat-card__value">{stats.orderCount}</Text>
          </View>
          <View className="promo-stat-card">
            <Text className="material-symbols-outlined promo-stat-card__icon">trending_up</Text>
            <Text className="promo-stat-card__label">转化率</Text>
            <Text className="promo-stat-card__value">{stats.conversionRate}%</Text>
          </View>
          <View className="promo-stat-card">
            <Text className="material-symbols-outlined promo-stat-card__icon">schedule</Text>
            <Text className="promo-stat-card__label">创建时间</Text>
            <Text className="promo-stat-card__value promo-stat-card__value--sm">
              {new Date(row.createdAt).toLocaleDateString('zh-CN')}
            </Text>
          </View>
        </View>
      )}

      <View className="hq-card" style="margin:0 16px">
        <Text className="hq-muted" style="display:block;font-size:12px;margin-bottom:8px">落地链接</Text>
        <Text style="display:block;font-size:13px;word-break:break-all">{row.landingUrl}</Text>
      </View>

      <View className="promo-detail-actions">
        <Button className="hq-btn hq-btn--outline hq-btn--block" onClick={copyLink}>
          复制推广链接
        </Button>
        <Button className="hq-btn hq-btn--primary hq-btn--block" onClick={downloadQr}>
          下载二维码
        </Button>
        <Button
          className="hq-btn hq-btn--ghost hq-btn--block"
          loading={updating}
          disabled={updating}
          onClick={toggleStatus}
        >
          {row.status === 'ACTIVE' ? '停用推广码' : '启用推广码'}
        </Button>
      </View>
    </View>
  );
}