import { Ref } from 'vue';
export interface StickToBottomOptions {
    /** How close to the bottom still counts as "at the bottom". */
    threshold?: number;
}
/**
 * Follow-the-stream policy: keep the user pinned to the bottom while they are
 * already there, and never yank them back once they scroll away.
 *
 * Programmatic scrolls are disambiguated from user scrolls by *position*, not
 * by bottom-ness: the guard remembers where the programmatic scroll was going
 * and releases when an event arrives at (or past) that position. Arrival must
 * not be judged by `atBottom` — content routinely grows between issuing the
 * scroll and its async event, so the event can land "not at the bottom
 * anymore" while being exactly the scroll we asked for; reading that as the
 * user walking away would silently disarm following. Any upward wheel input
 * still cancels everything immediately — the user always wins.
 */
export declare function useStickToBottom(element: Ref<HTMLElement | null>, options?: StickToBottomOptions): {
    atBottom: Ref<boolean, boolean>;
    following: Ref<boolean, boolean>;
    handleScroll: () => void;
    handleWheel: (event: WheelEvent) => void;
    scrollToBottom: (behavior?: ScrollBehavior) => void;
    tweenToBottom: (duration?: number) => Promise<boolean>;
    followIfSticking: (glideMs?: number) => void;
};