/**
 * 找对象页 U19-U20（TypeScript）
 *
 * 不变量（AGENTS.md）：
 *   - 第 2 条：Required 不可自动放宽——Discover 搜索仅透传筛选条件到后端
 *   - 第 4 条：Block 即时禁止互动
 *   - 第 6 条：单向意向不泄露
 */
// eslint-disable-next-line @typescript-eslint/no-unused-vars
import { matchStore, appStore, authStore } from '../../stores';
// eslint-disable-next-line @typescript-eslint/no-unused-vars
import { recommendationService } from '../../services';
// eslint-disable-next-line @typescript-eslint/no-unused-vars
import { to } from '../../constants';
import type { RecommendationCandidate } from '../../types';

interface DiscoverData {
  users: RecommendationCandidate[];
  loading: boolean;
  loadingMore: boolean;
  cursor: string | null;
  hasMore: boolean;
  keywordInput: string;
  showFilter: boolean;
  tempRegion: string;
  tempAgeMin: number;
  tempAgeMax: number;
  applied: { keyword: string; region: string; ageMin: number; ageMax: number };
  hasActiveFilter: boolean;
  regions: string[];
  actionLoadingUserId: string;
  emptyActions: Array<{ text: string; event: string; variant: string }>;
}

const DEFAULT_AGE_MIN = 18;
const DEFAULT_AGE_MAX = 60;
const PAGE_SIZE = 20;

Page({
  data: {
    users: [],
    loading: false,
    loadingMore: false,
    cursor: null,
    hasMore: true,
    keywordInput: '',
    showFilter: false,
    tempRegion: '',
    tempAgeMin: DEFAULT_AGE_MIN,
    tempAgeMax: DEFAULT_AGE_MAX,
    applied: { keyword: '', region: '', ageMin: DEFAULT_AGE_MIN, ageMax: DEFAULT_AGE_MAX },
    hasActiveFilter: false,
    regions: ['丹阳', '镇江', '南京'],
    actionLoadingUserId: '',
    emptyActions: [
      { text: '清空筛选', event: 'reset', variant: 'primary' },
      { text: '去今日推荐', event: 'home', variant: 'secondary' },
    ],
  },

  onLoad() {
    if (!authStore.state.isLoggedIn) return;
    this.fetchDiscover(true);
  },

  async fetchDiscover(first: boolean) {
    if (this.data.loading) return;
    this.setData({ loading: true });
    try {
      // @ts-ignore - recommendationService 接口待 TypeScript 化
      const result = await recommendationService.discover(this._buildParams());
      const items: RecommendationCandidate[] = (result?.items as RecommendationCandidate[]) || [];
      this.setData({
        users: first ? items : [...this.data.users, ...items],
        cursor: result?.nextCursor || null,
        hasMore: !!result?.nextCursor,
        loading: false,
      });
    } catch (err: unknown) {
      this.setData({ loading: false });
      appStore.toastError(err instanceof Error ? err.message : '加载失败');
    }
  },

  async loadMore() {
    if (this.data.loadingMore || !this.data.hasMore || !this.data.cursor) return;
    this.setData({ loadingMore: true });
    try {
      // @ts-ignore
      const result = await recommendationService.discover({
        ...this._buildParams(),
        cursor: this.data.cursor,
      });
      const items: RecommendationCandidate[] = (result?.items as RecommendationCandidate[]) || [];
      this.setData({
        users: [...this.data.users, ...items],
        cursor: result?.nextCursor || null,
        hasMore: !!result?.nextCursor,
      });
    } catch (err: unknown) {
      appStore.toastError(err instanceof Error ? err.message : '加载失败');
    } finally {
      this.setData({ loadingMore: false });
    }
  },

  _buildParams() {
    const { applied } = this.data;
    const params: Record<string, unknown> = { pageSize: PAGE_SIZE };
    if (applied.keyword) params.keyword = applied.keyword;
    if (applied.region) params.region = applied.region;
    if (applied.ageMin !== DEFAULT_AGE_MIN) params.ageMin = applied.ageMin;
    if (applied.ageMax !== DEFAULT_AGE_MAX) params.ageMax = applied.ageMax;
    return params;
  },

  onKeywordInput(e: any) {
    this.setData({ keywordInput: e.detail.value });
  },

  onSearch() {
    const keyword = (this.data.keywordInput || '').trim();
    const applied = { ...this.data.applied, keyword };
    this.setData({ applied, hasActiveFilter: this._hasActiveFilter(applied) });
    this.fetchDiscover(true);
  },

  toggleFilter() {
    this.setData({ showFilter: !this.data.showFilter });
  },

  onRegionTap(e: WechatMiniprogram.TouchEvent) {
    const val = (e.currentTarget.dataset as any).val as string;
    this.setData({ tempRegion: this.data.tempRegion === val ? '' : val });
  },

  onMinAgeChange(e: any) {
    let min = Number((e as any).detail.value);
    if (min > this.data.tempAgeMax) min = this.data.tempAgeMax;
    this.setData({ tempAgeMin: min });
  },

  onMaxAgeChange(e: any) {
    let max = Number((e as any).detail.value);
    if (max < this.data.tempAgeMin) max = this.data.tempAgeMin;
    this.setData({ tempAgeMax: max });
  },

  onApplyFilter() {
    const { tempRegion, tempAgeMin, tempAgeMax, keywordInput } = this.data;
    const applied = { keyword: (keywordInput || '').trim(), region: tempRegion, ageMin: tempAgeMin, ageMax: tempAgeMax };
    this.setData({ applied, hasActiveFilter: this._hasActiveFilter(applied), showFilter: false });
    this.fetchDiscover(true);
  },

  onResetFilter() {
    const applied = { keyword: '', region: '', ageMin: DEFAULT_AGE_MIN, ageMax: DEFAULT_AGE_MAX };
    this.setData({
      keywordInput: '', tempRegion: '', tempAgeMin: DEFAULT_AGE_MIN, tempAgeMax: DEFAULT_AGE_MAX,
      applied, hasActiveFilter: false, showFilter: false,
    });
    this.fetchDiscover(true);
  },

  _hasActiveFilter(applied: { keyword: string; region: string; ageMin: number; ageMax: number }) {
    return !!(
      applied.keyword || applied.region ||
      applied.ageMin !== DEFAULT_AGE_MIN || applied.ageMax !== DEFAULT_AGE_MAX
    );
  },

  onEmptyAction(e: WechatMiniprogram.TouchEvent) {
    const { event } = (e.detail as any) || {};
    if (event === 'reset') this.onResetFilter();
    else if (event === 'home') wx.switchTab({ url: '/pages/index/index' });
  },

  onViewDetail(e: WechatMiniprogram.TouchEvent) {
    const { userId } = (e.detail as any) || {};
    if (!userId) return;
    wx.navigateTo({ url: to.detail(userId) });
  },

  async onLike(e: WechatMiniprogram.TouchEvent) {
    const userId = (e.currentTarget.dataset as any).userId as string | undefined;
    if (!userId || this.data.actionLoadingUserId) return;
    this.setData({ actionLoadingUserId: userId });
    try {
      // @ts-ignore
      const result = await matchStore.like(userId);
      this.setData({ users: this.data.users.filter((u) => u.userId !== userId) });
      if (result?.mutualMatch) {
        appStore.toastSuccess('双向喜欢！可以开始聊天了');
        if (result.matchedConversationId) {
          wx.navigateTo({ url: to.chat(result.matchedConversationId) });
        }
      } else {
        appStore.toastSuccess('已表达喜欢');
      }
    } catch (err: unknown) {
      appStore.toastError(err instanceof Error ? err.message : '操作失败');
    } finally {
      this.setData({ actionLoadingUserId: '' });
    }
  },

  onPullDownRefresh() {
    this.fetchDiscover(true).finally(() => wx.stopPullDownRefresh());
  },

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