import * as plugins from '../plugins.js';
import { BaseDecoder } from './base.decoder.js';
/**
 * A decoder for Factur-X/ZUGFeRD XML format (based on UN/CEFACT CII).
 * Converts XML into structured ILetter with invoice data.
 */
export declare class FacturXDecoder extends BaseDecoder {
    private xmlDoc;
    constructor(xmlString: string);
    /**
     * Extracts text from the first element matching the tag name
     */
    private getElementText;
    /**
     * Converts Factur-X/ZUGFeRD XML to a structured letter object
     */
    getLetterData(): Promise<plugins.tsclass.business.ILetter>;
}