import type { TocItem } from './types.js';
/**
 * A live table of contents: the headings scanned from the current page, plus
 * the id of the section currently in view.
 */
export type Toc = {
    /** Headings of the current page, in document order. */
    readonly items: TocItem[];
    /** Id of the heading whose section is currently in view, or `null`. */
    readonly activeId: string | null;
    /** Re-scan the content element. Call after each navigation. */
    refresh: () => Promise<void>;
};
/**
 * Create a table of contents bound to a content element.
 *
 * Two jobs, both re-run whenever the page changes:
 * - `refresh()` re-scans the rendered headings (call it from `afterNavigate` so
 *   client-side navigation updates the list, not just a full reload).
 * - a single `IntersectionObserver` tracks which heading is in view for
 *   scroll-spy highlighting, re-observing the new headings after each refresh.
 *
 * Deliberately small: no section wrappers, no multi-threshold ratio math, no
 * parent-highlight bookkeeping. One observer, one active id.
 */
export declare function createToc(contentFn: () => HTMLElement | null): Toc;