/**
 * PDF bookmark (outline) extractor.
 *
 * Extracts the document outline tree from a PDF's `/Outlines` dictionary.
 * Each outline item has a title, a target page index, and optional children
 * forming a hierarchical bookmark tree.
 *
 * Supports:
 * - Direct destinations (`/Dest` as array or named destination)
 * - Action-based destinations (`/A << /S /GoTo /D ... >>`)
 * - Nested bookmarks (children via `/First`/`/Last` chains)
 * - Circular reference protection
 *
 * @see PDF Reference 1.7, §12.3 - Document-Level Navigation
 */
import type { PdfDocument } from "./pdf-document.js";
/** A bookmark (outline item) extracted from the PDF. */
export interface PdfBookmark {
    /** Bookmark title text */
    title: string;
    /** 0-based page index the bookmark points to (-1 if unresolvable) */
    pageIndex: number;
    /** Child bookmarks (nested outline items) */
    children: PdfBookmark[];
}
/**
 * Extract bookmarks (outlines) from a PDF document.
 *
 * Reads the `/Outlines` dictionary from the catalog and recursively
 * traverses the outline tree following `/First` → `/Next` chains.
 *
 * @param doc - The PDF document
 * @returns Array of top-level bookmarks with nested children
 */
export declare function extractBookmarks(doc: PdfDocument): PdfBookmark[];