import { AUTH_USER_CACHE_KEY } from '@/lib/api';

const PIN_IDLE_WATCH_KEY = 'auth:pin-idle-watch-user';

function readCachedUserId(): string | null {
  if (typeof window === 'undefined') return null;
  const raw = window.localStorage.getItem(AUTH_USER_CACHE_KEY);
  if (!raw) return null;
  try {
    const parsed = JSON.parse(raw) as { id?: string };
    return parsed.id ?? null;
  } catch {
    return null;
  }
}

export function markPinIdleWatch(userId?: string | null) {
  if (typeof window === 'undefined') return;
  const resolvedUserId = userId ?? readCachedUserId();
  if (!resolvedUserId) return;
  window.localStorage.setItem(PIN_IDLE_WATCH_KEY, resolvedUserId);
}

export function clearPinIdleWatch() {
  if (typeof window === 'undefined') return;
  window.localStorage.removeItem(PIN_IDLE_WATCH_KEY);
}

export function isPinIdleWatchActive(userId?: string | null) {
  if (typeof window === 'undefined') return false;
  const stored = window.localStorage.getItem(PIN_IDLE_WATCH_KEY);
  if (!stored) return false;
  const resolvedUserId = userId ?? readCachedUserId();
  return Boolean(resolvedUserId && stored === resolvedUserId);
}