import {createSessionCache, type SessionCache} from '$lib/sessionCache';

/**
 * Persists the current ('current') and old ('old') login sessions of an in-progress missing-blobs
 * import in localStorage so a page refresh can automatically restore them and offer to resume the
 * import instead of forcing the user to re-enter both passwords and re-trigger 2FA. This matters
 * most in the rate-limited case, where the user is told to come back in ~24h. All persistence
 * policy lives in the generic `sessionCache` factory; the `@pds-moover/moover` package only
 * exposes generic hooks (onSessionUpdate / restoreSessions).
 *
 * Only the current side is required: a refresh before the old-PDS login still resumes (restore the
 * current session, show the missing count, drop the user at the old-PDS password step). An
 * old-side-only orphan is cleared.
 *
 * Security note: this stores access + refresh JWTs in localStorage. Acceptable for this SPA,
 * mitigated by clearing on completion / start-over and by PasswordSession.resume() invalidating
 * dead sessions.
 */

const STORAGE_KEY = 'pdsmoover:missing-blobs-sessions:v1';

export type MissingBlobsSessionCache = SessionCache<'current' | 'old'>;

const cache = createSessionCache<'current' | 'old'>(STORAGE_KEY, ['current']);

/**
 * Persist (data) or drop (null) one side of the import. When both sides end up gone the whole key
 * is removed so we never leave an orphaned entry behind.
 */
export const saveSide = cache.saveSide;

/**
 * Read the cached sessions. Resume needs at least the current side; an old-side-only orphan is
 * cleared and null is returned.
 */
export const load = cache.load;

/** Remove the whole cache entry (completion / start-over / expired sessions). */
export const clear = cache.clear;