import type { Auth, OpaqueSession } from '@microsoft/rayfin-auth';
import type { FabricAuthOptions } from './types.js';
/**
 * Initializes embedded Fabric authentication if running inside an iframe
 * with `?fabricEmbedded=true`.
 *
 * Call this once at app startup (e.g., in a `useEffect` or initialization
 * routine). It is safe to call on page load — it never opens a popup or
 * new tab.
 *
 * **Behaviour:**
 * - If `fabricEmbedded=true` is **not** in the URL and `options.fabricEmbedded`
 *   is not `true`, returns `null` immediately (no-op).
 * - When the host stamps a `?_fu=` hint, runs the standard resume waterfall
 *   (existing session → refresh token → handoff).
 * - When it does not, skips resume on the first call per page load and goes
 *   straight to the handoff, preserving the pre-hint protection against reusing
 *   a previously signed-in Fabric user's session.
 *
 * Apps that also support the popup flow should continue to call
 * {@link ensureSignedInWithFabric} from a user-gesture handler for the
 * non-embedded case.
 *
 * @param auth - The Auth instance.
 * @param options - Fabric authentication options.
 * @returns The authenticated session, or `null` if not in embedded mode.
 */
export declare function initEmbeddedAuth(auth: Auth, options: FabricAuthOptions): Promise<OpaqueSession | null>;
//# sourceMappingURL=initEmbeddedAuth.d.ts.map