import { createHash } from "node:crypto";
import type {
  AddressLookupInput,
  MothershipAddressCandidate,
} from "@/modules/address/types";
import {
  getAddressCandidatesCache,
  setAddressCandidatesCache,
} from "@/modules/cache/redis-cache";

export type AddressCandidatesCachePayload = {
  pickup_candidates: MothershipAddressCandidate[];
  delivery_candidates: MothershipAddressCandidate[];
};

function normalizeAddressLookup(input: AddressLookupInput): string {
  return JSON.stringify({
    street: input.street.trim(),
    city: input.city.trim(),
    state: input.state.trim().toUpperCase(),
    zip: input.zip.trim(),
    country: (input.country ?? "USA").trim().toUpperCase(),
  });
}

/** pickup + delivery 草稿地址 MD5，用于 addr-cand 缓存键 */
export function buildAddressCandidatesCacheHash(input: {
  pickup: AddressLookupInput;
  delivery: AddressLookupInput;
}): string {
  const raw = [
    normalizeAddressLookup(input.pickup),
    normalizeAddressLookup(input.delivery),
  ].join("|");
  return createHash("md5").update(raw).digest("hex");
}

export async function loadAddressCandidatesCache(input: {
  pickup: AddressLookupInput;
  delivery: AddressLookupInput;
}): Promise<AddressCandidatesCachePayload | null> {
  try {
    const hash = buildAddressCandidatesCacheHash(input);
    return await getAddressCandidatesCache<AddressCandidatesCachePayload>(hash);
  } catch {
    return null;
  }
}

export async function saveAddressCandidatesCache(
  input: {
    pickup: AddressLookupInput;
    delivery: AddressLookupInput;
  },
  payload: AddressCandidatesCachePayload,
): Promise<void> {
  try {
    const hash = buildAddressCandidatesCacheHash(input);
    await setAddressCandidatesCache(hash, payload);
  } catch {
    // Redis 不可用时跳过缓存，不影响主流程
  }
}