/**
 * 积分 & 会员状态管理
 * 对齐后端 staging 最终契约（2026-09-16）：
 * - balance: GET /points/balance（无 free_clips_*）
 * - dailyUsage: GET /usage/daily（每日免费额度）
 * - membership: GET /points/subscription/membership（聚合会员信息）
 * - rules: GET /points/rules（base_points + free_user_multiplier）
 * - subscription: GET /subscription/current（plan_id + billing_cycle）
 */
import { create } from "zustand"
import { ENABLE_CREDIT_SYSTEM } from "@/config/features"
import { getPointsBalance, getPointsRules, getDailyUsage, getMembership } from "@/api/points"
import { getCurrentSubscription } from "@/api/subscription"
import type {
  PointsBalance,
  PointsRulesResponse,
  DailyUsage,
  MembershipResponse,
} from "@/api/points/types"
import type { SubscriptionInfo } from "@/api/subscription/types"

interface PointsState {
  balance: PointsBalance | null
  dailyUsage: DailyUsage | null
  membership: MembershipResponse | null
  rules: PointsRulesResponse | null
  subscription: SubscriptionInfo | null
  loading: boolean
  error: string | null
  /** 初始化：并行拉取 balance / rules / subscription / dailyUsage / membership */
  init: () => Promise<void>
  /** 刷新余额（充值/消费后调用） */
  refreshBalance: () => Promise<void>
  /** 乐观扣减 */
  optimisticDeduct: (points: number) => void
  /** 乐观增加 */
  optimisticAdd: (points: number) => void
  /** 清除积分状态（退出登录） */
  reset: () => void
}

export const usePointsStore = create<PointsState>((set, get) => ({
  balance: null,
  dailyUsage: null,
  membership: null,
  rules: null,
  subscription: null,
  loading: false,
  error: null,

  init: async () => {
    // 已加载过不重复拉取
    // 积分系统关闭时：只要 subscription/membership 已有值就跳过；开启时需 balance+rules+subscription 齐了才跳过
    if (ENABLE_CREDIT_SYSTEM) {
      if (get().balance && get().rules && get().subscription) return
    } else {
      if (get().subscription && get().membership) return
    }
    set({ loading: true, error: null })
    try {
      // 积分系统关闭时不拉取余额/规则/每日额度，但仍拉会员/订阅用于 VIP 标识展示
      const balancePromise = ENABLE_CREDIT_SYSTEM
        ? getPointsBalance().catch(() => null)
        : Promise.resolve(null)
      const rulesPromise = ENABLE_CREDIT_SYSTEM
        ? getPointsRules().catch(() => null)
        : Promise.resolve(null)
      const dailyUsagePromise = ENABLE_CREDIT_SYSTEM
        ? getDailyUsage().catch(() => null)
        : Promise.resolve(null)
      const [balance, rules, subscription, dailyUsage, membership] = await Promise.all([
        balancePromise,
        rulesPromise,
        getCurrentSubscription().catch(() => null),
        dailyUsagePromise,
        getMembership().catch(() => null),
      ])
      set({
        balance,
        rules,
        subscription,
        dailyUsage,
        membership,
        loading: false,
      })
    } catch (err) {
      set({ error: (err as Error).message || "加载积分信息失败", loading: false })
    }
  },

  refreshBalance: async () => {
    try {
      const [balance, dailyUsage, membership, subscription] = await Promise.all([
        getPointsBalance(),
        getDailyUsage().catch(() => null),
        getMembership().catch(() => null),
        getCurrentSubscription().catch(() => get().subscription),
      ])
      set({ balance, dailyUsage, membership, subscription })
    } catch (err) {
      set({ error: (err as Error).message || "刷新积分失败" })
    }
  },

  optimisticDeduct: (points: number) => {
    const { balance, membership } = get()
    if (!balance) return
    set({
      balance: {
        ...balance,
        balance: Math.max(0, balance.balance - points),
        total_spent: balance.total_spent + points,
      },
      membership: membership
        ? { ...membership, points_balance: Math.max(0, membership.points_balance - points) }
        : null,
    })
  },

  optimisticAdd: (points: number) => {
    const { balance, membership } = get()
    if (!balance) return
    set({
      balance: {
        ...balance,
        balance: balance.balance + points,
        total_earned: balance.total_earned + points,
      },
      membership: membership
        ? { ...membership, points_balance: membership.points_balance + points }
        : null,
    })
  },

  reset: () => {
    set({
      balance: null,
      dailyUsage: null,
      membership: null,
      rules: null,
      subscription: null,
      loading: false,
      error: null,
    })
  },
}))