import { type RefObject } from "react";
export interface SectionNavHandle<K extends string> {
    /** Attach to the SCROLLING element — the one carrying `overflow-y`. */
    scrollRef: RefObject<HTMLDivElement | null>;
    /** The section the scroll currently sits in — drives the rail item's `current`. */
    activeKey: K;
    /** `ref={register(key)}` on each section. Stable per key, so a re-render never
     *  detaches and re-attaches the node. */
    register: (key: K) => (node: HTMLElement | null) => void;
    /** Scroll to a section — the rail item's `onPress`. */
    jumpTo: (key: K) => void;
    /** `onScroll={nav.onScroll}` on the same element. It carries nothing: every
     *  measurement is read off `scrollRef`. */
    onScroll: () => void;
}
/**
 * Scroll-spy for a LONG record surface with a left outline rail: one scrolling
 * page whose sections register their nodes, a rail that jumps to them, and an
 * `activeKey` that follows the scroll.
 *
 * Pass the keys in PAGE ORDER — the spy walks them top-down.
 *
 * Both the jump AND the highlight read the live DOM position, so async content
 * growing ABOVE a section can never stale either. A section that unmounts keeps
 * its last measured offset rather than collapsing to the page top.
 *
 * The LAST key is active whenever the scroll reaches the end: a final section
 * shorter than the viewport never scrolls its top past the trigger line.
 */
export declare function useSectionNav<K extends string>(keys: readonly [K, ...K[]]): SectionNavHandle<K>;