import AsyncStorage from "@react-native-async-storage/async-storage";
import { create } from "zustand";
import { createJSONStorage, persist } from "zustand/middleware";
import { seedSubscriptions } from "@/lib/data/seed";
import type { Fulfillment, PaymentMethod } from "@/lib/stores/locationStore";

export type SubscriptionStatus = "active" | "paused" | "cancelled";

export type RefillSubscription = {
  id: string;
  productId: string;
  productName: string;
  quantity: number;
  frequencyDays: number;
  fulfillment: Fulfillment;
  paymentMethod: PaymentMethod;
  memberId?: string | null;
  status: SubscriptionStatus;
  nextFulfillmentAt: string;
};

type SubState = {
  items: RefillSubscription[];
  add: (
    s: Omit<RefillSubscription, "id" | "status" | "nextFulfillmentAt">
  ) => void;
  pause: (id: string) => void;
  resume: (id: string) => void;
  cancel: (id: string) => void;
};

function nextDate(days: number) {
  const d = new Date();
  d.setDate(d.getDate() + days);
  return d.toISOString();
}

export const useSubscriptionStore = create<SubState>()(
  persist(
    (set, get) => ({
      items: seedSubscriptions,
      add: (s) =>
        set({
          items: [
            {
              ...s,
              id: `sub_${Date.now()}`,
              status: "active",
              nextFulfillmentAt: nextDate(s.frequencyDays),
            },
            ...get().items,
          ],
        }),
      pause: (id) =>
        set({
          items: get().items.map((i) =>
            i.id === id ? { ...i, status: "paused" } : i
          ),
        }),
      resume: (id) =>
        set({
          items: get().items.map((i) =>
            i.id === id
              ? {
                  ...i,
                  status: "active",
                  nextFulfillmentAt: nextDate(i.frequencyDays),
                }
              : i
          ),
        }),
      cancel: (id) =>
        set({
          items: get().items.map((i) =>
            i.id === id ? { ...i, status: "cancelled" } : i
          ),
        }),
    }),
    {
      name: "gishen-subscriptions",
      storage: createJSONStorage(() => AsyncStorage),
      version: 2,
      migrate: (persisted: unknown) => {
        const state = (persisted ?? {}) as Partial<SubState>;
        return !state.items?.length
          ? { ...state, items: seedSubscriptions }
          : state;
      },
    }
  )
);