/**
 * 公益活动列表页 U31
 *
 * 重构要点（遵循 AGENTS.md 不变量）：
 *   - 数据：ActivityStore.fetchActivities / loadMoreActivities（游标分页）
 *   - 列表项：ui-activity-card 组件，"公益免费"为主视觉标识（AGENTS 第 1 条：用户永久免费）
 *   - 跳转：点击卡片 → activity-detail，不在列表页处理报名
 *   - 单向意向保密：本页不接入互选意向提交（仅在 activity-matches 页由用户主动操作，AGENTS 第 6 条）
 *   - 下拉刷新 + onReachBottom 加载更多
 */
import { activityStore, appStore, authStore } from '../../stores';
import { to } from '../../constants';

interface ActivityCategory {
  code: string;
  label: string;
}

/**
 * 列表项。沿用共享 Activity 类型，并允许服务端附加分类字段用于本地筛选。
 * 分类字段在共享类型中尚未收敛，此处显式声明，避免用 any 绕过类型检查。
 */
interface ActivityListItem {
  activityId?: string;
  id?: string;
  activityType?: string;
  category?: string;
  [key: string]: unknown;
}

interface ActivityPageData {
  activities: ActivityListItem[];
  loading: boolean;
  loadingMore: boolean;
  hasMore: boolean;
  firstLoaded: boolean;
  activeCategory: string;
  categories: ActivityCategory[];
  emptyConfig: {
    title: string;
    description: string;
    illustration: string;
    actions: Array<{ text: string; event: string; variant: string }>;
  };
}

Page({
  data: {
    activities: [] as ActivityListItem[],
    loading: false,
    loadingMore: false,
    hasMore: true,
    firstLoaded: false,
    activeCategory: 'all',
    /**
     * 分类 Tabs。
     *
     * <p><b>Phase 14 修复</b>：code 必须**逐字等于**后端 {@code activities.activity_type}
     * 的取值（生产约束 {@code chk_activity_type} 白名单）。此前这里写的是
     * {@code classroom}，而生产白名单里根本没有该值（婚恋课堂是
     * {@code relationship_education}）—— 点「婚恋课堂」Tab 恒为空白页。
     *
     * <p>守卫 {@code ActivityConstraintGuardTest#miniappCategoryCodesWithinProductionWhitelist}
     * 会解析真实 DDL 校验本数组，改错即刻变红。
     */
    categories: [
      { code: 'all', label: '全部' },
      { code: 'matchmaking', label: '公益联谊' },
      { code: 'interest_social', label: '兴趣社交' },
      { code: 'relationship_education', label: '婚恋课堂' },
      { code: 'premarital_guidance', label: '婚前辅导' },
      { code: 'marriage_custom_culture', label: '婚俗文化' },
      { code: 'anti_fraud', label: '反诈宣传' },
    ] as ActivityCategory[],
    /** @type {{title:string, description:string, illustration:string, actions:Array}} */
    emptyConfig: {
      title: '暂无进行中的活动',
      description: '近期暂无报名中的公益活动，请稍后再来',
      illustration: 'activity',
      actions: [
        { text: '我的活动', event: 'my', variant: 'secondary' },
      ],
    },
  } as ActivityPageData,

  onLoad() {
    if (!authStore.state.isLoggedIn) return;
    (this as any)._unsub = activityStore.bindToPage(this, {
      activities: 'activities',
      activitiesHasMore: 'activitiesHasMore',
    });
    this.fetchActivities(true);
  },

  onShow() {
    if (!authStore.state.isLoggedIn) return;
    // 从活动详情返回后，若列表为空则刷新（避免详情页报名后列表不同步）
    if (this.data.firstLoaded && this.data.activities.length === 0) {
      this.fetchActivities(true);
    }
  },

  onUnload() {
    if ((this as any)._unsub) (this as any)._unsub();
  },

  /** 首次或下拉刷新拉取活动列表 */
  async fetchActivities(_first = false) {
    if (this.data.loading) return;
    this.setData({ loading: true });
    try {
      await activityStore.fetchActivities();
      this.applyActivityFilter();
      this.setData({
        loading: false,
        firstLoaded: true,
        hasMore: activityStore.state.activitiesHasMore,
      });
    } catch (err) {
      this.setData({ loading: false, firstLoaded: true });
      appStore.toastError(err, '加载活动失败');
    }
  },

  /** 加载更多（onReachBottom 触发） */
  async loadMore() {
    if (this.data.loadingMore || !this.data.hasMore) return;
    this.setData({ loadingMore: true });
    try {
      await activityStore.loadMoreActivities();
      this.applyActivityFilter();
      this.setData({
        loadingMore: false,
        hasMore: activityStore.state.activitiesHasMore,
      });
    } catch (err) {
      this.setData({ loadingMore: false });
      appStore.toastError(err, '加载更多失败');
    }
  },

  onPullDownRefresh() {
    this.fetchActivities(true).then(() => {
      wx.stopPullDownRefresh();
    });
  },

  onReachBottom() {
    this.loadMore();
  },

  onCategoryTap(e: WechatMiniprogram.TouchEvent) {
    this.setData({ activeCategory: e.currentTarget.dataset.code as string });
    this.applyActivityFilter();
  },

  applyActivityFilter() {
    const source = (activityStore.state.activities || []) as ActivityListItem[];
    const { activeCategory } = this.data;
    this.setData({
      activities: activeCategory === 'all'
        ? source
        : source.filter((item) => (item.activityType || item.category) === activeCategory),
    });
  },

  /** 点击活动卡片 → 跳转详情 */
  onActivityTap(e: any) {
    const activityId = e.detail.activityId;
    if (!activityId) return;
    wx.navigateTo({ url: to.activityDetail(activityId) });
  },

  /** 空状态：去我的活动 */
  onEmptyAction(e: any) {
    const { event } = e.detail;
    if (event === 'my') {
      wx.navigateTo({ url: '/pages/my-activities/my-activities' });
    }
  },

  /** 顶部"我的活动"入口 */
  onMyActivities() {
    wx.navigateTo({ url: '/pages/my-activities/my-activities' });
  },
});