import { PDFArray } from '../core/pdf-array.ts';
import { PDFRef } from '../core/pdf-ref.ts';
import type { PDFWriter } from '../core/pdf-writer.ts';
/**
 * Represents a PDF cross-reference (xref) section, which maps object
 * numbers to their byte offsets in the PDF file or to object streams.
 */
export declare class PDFXRefSection {
    private readonly entries;
    /**
     * Constructs a new PDFXRefSection instance.
     */
    constructor();
    /**
     * Adds an entry for an object at a byte offset, or a free entry if deleted.
     * For free entries, the offset is used as the "next free object number" field.
     */
    addEntry(ref: PDFRef, offset: number, deleted?: boolean): void;
    /**
     * Adds a type 2 entry for an object stored in an object stream.
     * @param ref The reference to the object
     * @param streamObjNum The object number of the containing object stream
     * @param index The index of the object within the object stream
     */
    addObjectStreamEntry(ref: PDFRef, streamObjNum: number, index: number): void;
    /**
     * Returns true if this section contains any type 2 (object stream) entries.
     */
    hasObjectStreamEntries(): boolean;
    /**
     * Writes the xref section as a traditional xref table to the given PDFWriter.
     * Note: Type 2 entries (object stream references) cannot be represented in
     * a traditional xref table - use an xref stream instead.
     */
    write(writer: PDFWriter): void;
    private writeSubsection;
    /**
     * Writes the xref section as a compressed xref stream (PDF 1.5+).
     * The xref stream combines the cross-reference data and trailer into
     * a single compressed stream object.
     *
     * @param writer The PDFWriter to write to
     * @param lastObjNum The highest object number assigned so far (excluding
     *   the xref stream itself). The xref stream will be assigned the next
     *   object number (`lastObjNum + 1`).
     * @param trailerEntries Additional trailer dictionary entries (Root, Info, ID, etc.)
     * @returns The byte offset where the xref stream was written
     */
    writeAsStream(writer: PDFWriter, lastObjNum: number, trailerEntries: {
        Root: PDFRef;
        Info?: PDFRef;
        ID: PDFArray;
    }, compress?: boolean): number;
    /**
     * Builds the binary xref stream data, calculates field widths, and
     * computes the /Index array if entries are non-contiguous or don't
     * start at 0.
     */
    private buildXRefStreamData;
}