export type WebdavStatus = "unknown" | "ready" | "failed";

interface WebdavStatusCache {
  signature: string;
  status: WebdavStatus;
  updatedAt: number;
}

const WEBDAV_STATUS_KEY = "webdav_status_cache";

export const buildWebdavSignature = (
  verge?: Pick<
    IVergeConfig,
    "webdav_url" | "webdav_username" | "webdav_password"
  > | null,
) => {
  const url = verge?.webdav_url?.trim() ?? "";
  const username = verge?.webdav_username?.trim() ?? "";
  const password = verge?.webdav_password ?? "";

  if (!url && !username && !password) return "";

  return JSON.stringify([url, username, password]);
};

const canUseStorage = () => typeof localStorage !== "undefined";

export const getWebdavStatus = (signature: string): WebdavStatus => {
  if (!signature || !canUseStorage()) return "unknown";

  const raw = localStorage.getItem(WEBDAV_STATUS_KEY);
  if (!raw) return "unknown";

  try {
    const data = JSON.parse(raw) as Partial<WebdavStatusCache>;
    if (!data || data.signature !== signature) return "unknown";
    return data.status === "ready" || data.status === "failed"
      ? data.status
      : "unknown";
  } catch {
    return "unknown";
  }
};

export const setWebdavStatus = (signature: string, status: WebdavStatus) => {
  if (!signature || !canUseStorage()) return;

  const payload: WebdavStatusCache = {
    signature,
    status,
    updatedAt: Date.now(),
  };

  localStorage.setItem(WEBDAV_STATUS_KEY, JSON.stringify(payload));
};