import cloud from "@lafjs/cloud";
import Utils from "@/Utils";
import { openPeriodForUser, openingRuleForUser } from "@/cloudRise/periods";

const LOOKAHEAD_MS = 7 * 24 * 60 * 60 * 1000;
const REFRESH_MS = 30 * 1000;

type ActivityInfo = {
  activityId: string;
  periodId: string;
  configVersion: string;
  startsAt: number;
  endsAt: number;
  unlockLevel: number;
  phase: "active" | "upcoming";
  purchaseEnabled?: boolean;
};

/** Only an explicit HomeScene request creates a period; listing is read only. */
async function cloudRiseActivities(now: number, _windowEndsAt: number, user: any) {
  const period = openPeriodForUser(user, now);
  const activities: ActivityInfo[] = period ? [{ activityId: "cloudRise", periodId: period.periodId, configVersion: period.configVersion,
    startsAt: period.startsAt, endsAt: period.endsAt, unlockLevel: period.unlockLevel, phase: "active" }] : [];
  return { activities, openingRules: user ? [await openingRuleForUser(user, now)] : [] };
}

// 百人赛单独上线：黄金矿工暂不注册，也不导入其尚未部署的模块。
const providers = [cloudRiseActivities];

export async function activityList(now = Date.now(), user: any = null) {
  const windowEndsAt = now + LOOKAHEAD_MS;
  const results = await Promise.all(providers.map(provider => provider(now, windowEndsAt, user)));
  const candidates = results.flatMap(result => result.activities);
  const openingRules = results.flatMap(result => result.openingRules);
  // Each activity exposes one period: current first, otherwise the earliest upcoming period.
  // Overlapping current periods keep the existing latest-start precedence.
  candidates.sort((a, b) => a.activityId < b.activityId ? -1 : a.activityId > b.activityId ? 1
    : Number(b.startsAt <= now) - Number(a.startsAt <= now)
      || (a.startsAt <= now ? b.startsAt - a.startsAt : a.startsAt - b.startsAt)
      || (a.periodId < b.periodId ? -1 : a.periodId > b.periodId ? 1 : 0));
  const selected = new Set<string>();
  const activities = candidates.filter(activity => {
    if (selected.has(activity.activityId)) return false;
    selected.add(activity.activityId); return true;
  });
  let refreshAt = now + REFRESH_MS;
  // A currently hidden test period may take precedence when it starts; refresh at that boundary too.
  for (const activity of candidates) {
    for (const boundary of [activity.startsAt, activity.endsAt]) {
      if (boundary > now) refreshAt = Math.min(refreshAt, boundary);
    }
  }
  return { schemaVersion: 1, serverNow: now, windowEndsAt, refreshAt, activities, openingRules };
}

/** Authenticated users receive their personal CloudRise window; anonymous callers see public activities only. */
export default async function (ctx: FunctionContext) {
  try {
    const body = ctx.body || {}, supplied = body.uid !== undefined;
    let user: any = null;
    if (supplied) {
      const uid = typeof body.uid === "number" ? body.uid
        : typeof body.uid === "string" && /^[1-9]\d*$/.test(body.uid) ? Number(body.uid) : NaN;
      if (!Number.isSafeInteger(uid) || uid < 1) return { code: 0, msg: "玩家 uid 无效", data: null };
      user = await (cloud.mongo.db as any).collection("users").findOne({ onlyId: uid });
      if (!user?.token || !Utils.checkToken(body.token, user.token)) return { code: 0, msg: "token校验失败", data: null };
    }
    return { code: 1, msg: "ok", data: await activityList(Date.now(), user) };
  }
  catch (error) {
    console.error("activityConfig/list query failed", error);
    // A failed query must not look like a successful empty list and erase a client's cached entries.
    return { code: 0, msg: "活动信息暂时无法获取，请稍后重试", data: null };
  }
}