/**
 * 按俱乐部 + page_key 拉取公告/轮播（必须带 X-Club-Id）
 * 约定（与星阙小程序一致，注意与客服后台中文名曾有历史对调感）：
 *   order_pool   → 点单商城首页
 *   accept_order → 抢单池页
 *   merchant_home → 商家首页
 * 禁止多页共用同一个 shangpinlunbo 槽，否则会串台。
 */
import { buildClubHeaders, getClubId } from './club-context';

function ensureGonggaoStore(app) {
  const g = app.globalData || {};
  if (!g._gonggaoByPage) g._gonggaoByPage = {};
  return g._gonggaoByPage;
}

/** 读取某页面的缓存（按 club_id + page_key 隔离） */
export function getCachedGonggaoLunbo(app, pageKey = 'order_pool') {
  app = app || getApp();
  const cid = getClubId(app);
  const store = ensureGonggaoStore(app);
  const entry = store[pageKey];
  if (entry && entry.clubId === cid) {
    return {
      shangpingonggao: entry.shangpingonggao || '',
      shangpinlunbo: entry.shangpinlunbo || [],
    };
  }
  // 兼容旧版单槽缓存（仅当 page_key 一致时才命中）
  const g = app.globalData || {};
  if (g._gonggaoPageKey === pageKey && g._gonggaoClubId === cid) {
    return {
      shangpingonggao: g.shangpingonggao || '',
      shangpinlunbo: g.shangpinlunbo || [],
    };
  }
  return null;
}

export function isGonggaoCacheValid(app, pageKey = 'order_pool') {
  const cached = getCachedGonggaoLunbo(app, pageKey);
  if (!cached) return false;
  return !!(cached.shangpingonggao || (cached.shangpinlunbo && cached.shangpinlunbo.length));
}

export function applyGonggaoToGlobal(app, data, pageKey = 'order_pool') {
  if (!data) return;
  const g = app.globalData;
  const payload = {
    shangpingonggao: data.shangpingonggao || '',
    shangpinlunbo: data.shangpinlunbo || [],
    clubId: getClubId(app),
  };
  ensureGonggaoStore(app)[pageKey] = payload;
  // 保留直读字段，但必须记下 page_key，避免跨页误用
  g.shangpingonggao = payload.shangpingonggao;
  g.shangpinlunbo = payload.shangpinlunbo;
  g._gonggaoClubId = payload.clubId;
  g._gonggaoPageKey = pageKey;
}

export function fetchGonggaoLunbo(app, pageKey = 'order_pool') {
  const apiBase = app.globalData && app.globalData.apiBaseUrl;
  if (!apiBase) {
    return Promise.resolve(null);
  }
  return new Promise((resolve, reject) => {
    wx.request({
      url: `${apiBase}/peizhi/shangpingonggao/`,
      method: 'POST',
      header: buildClubHeaders({ 'content-type': 'application/json' }),
      data: { page_key: pageKey },
      success: (res) => {
        if (res.statusCode === 200 && res.data) {
          applyGonggaoToGlobal(app, res.data, pageKey);
          resolve(res.data);
        } else {
          reject(new Error('shangpingonggao 请求失败'));
        }
      },
      fail: reject,
    });
  });
}