import { PdfXmpMetadata } from './pdf-xmp-metadata';
/**
 * Internal XML reader for parsing XMP metadata from PDF streams.
 * Reads RDF/XML format and reconstructs PdfXmpMetadata with all schemas.
 *
 * @private
 */
export declare class _XmlReader {
    private _xmlDoc;
    private _xmp;
    /**
     * Loads and parses XML data from a byte array or string.
     *
     * @private
     * @param {Uint8Array | string} data The XML data to parse.
     * @returns {void}
     */
    _load(data: Uint8Array | string): void;
    /**
     * Validates the parsed XML document for errors.
     *
     * @private
     * @param {Document} doc The XML document to validate.
     * @returns {void}
     */
    private _validate;
    /**
     * Parses the loaded XML document into a PdfXmpMetadata object.
     *
     * @private
     * @returns {PdfXmpMetadata} The parsed metadata object.
     */
    _parseXmp(): PdfXmpMetadata;
    /**
     * Locates the rdf:RDF root element in the XML document.
     *
     * @private
     * @returns {Element} The rdf:RDF element.
     */
    private _getRdfRoot;
    /**
     * Parses a single rdf:Description node and routes to appropriate schema parser.
     *
     * @private
     * @param {Element} node The rdf:Description element.
     * @returns {void}
     */
    private _parseSchemaNode;
    /**
     * Routes schema parsing based on namespace URI.
     *
     * @private
     * @param {string} prefix The namespace prefix.
     * @param {string} ns The namespace URI.
     * @param {Element} node The rdf:Description element.
     * @returns {void}
     */
    private _mapSchema;
    /**
     * Parses Basic XMP schema properties.
     *
     * @private
     * @param {Element} node The rdf:Description element.
     * @returns {void}
     */
    private _parseBasic;
    /**
     * Parses Dublin Core schema properties.
     *
     * @private
     * @param {Element} node The rdf:Description element.
     * @returns {void}
     */
    private _parseDublinCore;
    /**
     * Parses PDF schema properties.
     *
     * @private
     * @param {Element} node The rdf:Description element.
     * @returns {void}
     */
    private _parsePdf;
    /**
     * Parses Paged-Text schema properties.
     *
     * @private
     * @param {Element} node The rdf:Description element.
     * @returns {void}
     */
    private _parsePagedText;
    /**
     * Parses Rights Management schema properties.
     *
     * @private
     * @param {Element} node The rdf:Description element.
     * @returns {void}
     */
    private _parseRights;
    /**
     * Parses Basic Job Ticket schema properties.
     *
     * @private
     * @param {Element} node The rdf:Description element.
     * @returns {void}
     */
    private _parseJobTicket;
    /**
     * Parses custom schema properties.
     *
     * @private
     * @param {string} prefix The namespace prefix.
     * @param {string} ns The namespace URI.
     * @param {Element} node The rdf:Description element.
     * @returns {void}
     */
    private _parseInternalCustom;
    /**
     * Parses custom schema properties.
     *
     * @private
     * @param {string} prefix The namespace prefix.
     * @param {string} ns The namespace URI.
     * @param {Element} node The rdf:Description element.
     * @returns {void}
     */
    private _parseCustom;
    /**
     * Gets a single text value from a child element.
     *
     * @private
     * @param {Element} node The parent element.
     * @param {string} tag The local name of the child element.
     * @returns {string} The text content or undefined.
     */
    private _getValue;
    /**
     * Gets the full attribute name for a tag, checking all possible namespace prefixes.
     *
     * @private
     * @param {Element} node The element to check.
     * @param {string} localName The local name to search for.
     * @returns {string} The attribute name or null.
     */
    private _getAttributeName;
    /**
     * Gets a Date value from a child element.
     *
     * @private
     * @param {Element} node The parent element.
     * @param {string} tag The local name of the child element.
     * @returns {Date} The parsed date or undefined.
     */
    private _getDate;
    /**
     * Gets an array of string values from an rdf:Bag or rdf:Seq container.
     *
     * @private
     * @param {Element} node The parent element.
     * @param {string} tag The local name of the property element.
     * @returns {string[]} Array of string values.
     */
    private _getArray;
    /**
     * Gets a multilingual array (language map) from an rdf:Alt container.
     *
     * @private
     * @param {Element} node The parent element.
     * @param {string} tag The local name of the property element.
     * @returns {PdfXmpLangArray} Language map object.
     */
    private _getLangArray;
    /**
     * Gets an array of structured thumbnail objects from an rdf:Bag container.
     *
     * @private
     * @param {Element} node The parent element.
     * @param {string} tag The local name of the property element.
     * @returns {PdfXmpThumbnail[]} Array of thumbnail structures.
     */
    private _getThumbnails;
    /**
     * Finds a child element by local name (case-insensitive for namespaces).
     *
     * @private
     * @param {Element} node The parent element.
     * @param {string} localName The local name to search for.
     * @returns {Element} The found element or null.
     */
    private _findChildElement;
    /**
     * Finds a direct child element by local name.
     *
     * @private
     * @param {Element} node The parent element.
     * @param {string} localName The local name to search for.
     * @returns {Element} The found element or null.
     */
    private _findDirectChild;
    /**
     * Finds all direct child elements with the specified local name.
     *
     * @private
     * @param {Element} node The parent element.
     * @param {string} localName The local name to search for.
     * @returns {Element[]} Array of matching elements.
     */
    private _findDirectChildren;
}