import { type Ref } from "vue";
export interface UsePinToSendOptions {
    scrollRef: Ref<HTMLElement | null>;
    contentRef: Ref<HTMLElement | null>;
    spacerRef: Ref<HTMLElement | null>;
    topOffset?: number;
}
/**
 * Vue counterpart of React's `usePinToSend` (`packages/react-core/src/v2/hooks/use-pin-to-send.ts`).
 *
 * Anchors the chat scroll container so the most recent user message stays
 * pinned near the top of the viewport while the assistant streams a
 * response beneath it.
 *
 * Implementation parity with React:
 * - Reads the latest user message via the `LastUserMessageContext`
 *   equivalent (`LastUserMessageKey` + `Ref<LastUserMessageState>`).
 * - On each `sendNonce` increment, sizes the spacer to
 *   `viewportHeight - bubbleHeight - topOffset` and scrolls so the bubble
 *   sits `topOffset` from the viewport top (padding above the bubble is
 *   pushed off-screen).
 * - Installs a shrink-only `ResizeObserver` on `contentRef` that collapses
 *   the spacer as the assistant response grows; never grows it back.
 * - Cancels the scheduled `requestAnimationFrame` and disconnects the
 *   `ResizeObserver` on subsequent re-runs and on scope dispose.
 */
export declare function usePinToSend({ scrollRef, contentRef, spacerRef, topOffset, }: UsePinToSendOptions): void;
//# sourceMappingURL=use-pin-to-send.d.ts.map