/**
 * TrueType font subsetting and PDF embedding.
 *
 * Takes a parsed TrueType font and a set of used Unicode code points,
 * and produces:
 * 1. A subsetted font program (binary TTF with only the needed glyphs)
 * 2. A CID-to-GID mapping for the CIDFont dictionary
 * 3. A ToUnicode CMap for text extraction/search
 * 4. Width arrays for the PDF font descriptor
 *
 * PDF embedding uses a Type0 (composite) font structure:
 *   Type0 font → CIDFont (CIDFontType2) → embedded TrueType font program
 *
 * The CID-to-GID mapping is Identity (CID = new GID in the subset).
 * Character codes in the content stream are 2-byte big-endian glyph IDs.
 *
 * @see PDF Reference 1.7, §5.6 - Composite Fonts
 * @see PDF Reference 1.7, §5.9 - ToUnicode CMaps
 */
import type { PdfWriter } from "../core/pdf-writer.js";
import type { TtfFont } from "./ttf-parser.js";
/**
 * Result of embedding a font into a PDF.
 */
export interface EmbeddedFont {
    /** PDF resource name (e.g., "EF1") */
    resourceName: string;
    /** Object number of the Type0 font dictionary */
    fontObjNum: number;
    /** The parsed TTF font */
    font: TtfFont;
    /**
     * Map from Unicode code point → CID (= new glyph index in subset).
     * Only contains characters that were actually used.
     */
    unicodeToCid: Map<number, number>;
    /** Advance widths in font units, indexed by CID */
    cidWidths: number[];
}
/**
 * Embed a TrueType font into a PDF document.
 *
 * @param writer - The PDF writer to add objects to
 * @param font - Parsed TrueType font
 * @param usedCodePoints - Set of Unicode code points used in the document
 * @param resourceName - PDF resource name (e.g., "EF1")
 * @returns Embedded font info
 */
export declare function embedTtfFont(writer: PdfWriter, font: TtfFont, usedCodePoints: Set<number>, resourceName: string): EmbeddedFont;