import { AnnotationBase } from "../Annotations/AnnotationTypes";
import GcPdfViewer from "../GcPdfViewer";
/**
 * Class to handle importing and exporting annotation data in XFDF format.
 * This class handles annotations and widget fields separately, supporting the export of PDF annotations and widget field data in the XFDF format.
 */
export declare class XFDFAnnotationHandler {
    viewer: GcPdfViewer;
    constructor(viewer: GcPdfViewer);
    /**
     * Exports annotations and widget field data to XFDF format.
     * Annotations are exported under the <annots> tag, and widget fields under the <fields> tag.
     *
     * @param filterFn Optional filter function to selectively export annotations or widget fields.
     * @returns A promise resolving to a string containing the XFDF representation of annotations and widget fields.
     */
    exportAnnotationsToXFDF(filterFn?: (annotation: AnnotationBase) => boolean): Promise<string>;
    /**
     * Builds the <annots> section of the XFDF content.
     * This method converts annotation objects to their corresponding XFDF tags.
     *
     * @param annotations The array of annotations to convert.
     * @returns A string containing the <annots> section.
     */
    private buildAnnotationsTag;
    /**
     * Builds the <fields> section of the XFDF content.
     * This method converts widget fields to their corresponding XFDF tags.
     *
     * @param widgetFields The array of widget field objects to convert.
     * @returns A string containing the <fields> section.
     */
    private buildWidgetFieldsTag;
    /**
     * Converts an annotation object to XFDF format.
     * Handles converting annotation properties to the appropriate XFDF XML element.
     *
     * @param annotation The annotation object to convert to XFDF.
     * @returns A string representing the annotation in XFDF format.
     */
    private annotationToXFDF;
    /**
     * Builds the <fields> section of the XFDF content.
     * This method converts widget fields to their corresponding XFDF tags.
     *
     * @param widgetFields The array of widget field objects to convert.
     * @returns A string containing the <fields> section.
     */
    private widgetFieldToXFDF;
    /**
     * Returns the correct XFDF tag name based on the annotation type.
     * This method ensures the annotation type is correctly mapped to XFDF-compatible tags.
     *
     * @param annotationType The annotation type to convert to XFDF tag name.
     * @returns The corresponding XFDF tag name.
     */
    private getAnnotationTypeName;
    /**
     * Imports annotation data from XFDF format.
     * Parses the XFDF XML data, converts each annotation element back to an annotation object.
     *
     * @param xfdfString The XFDF string containing annotation data to import.
     * @param filterFn Optional filter function to selectively import annotations or widget fields.
     * @returns An array of imported annotations.
     */
    importAnnotationsFromXFDF(xfdfString: string, filterFn?: (annotation: AnnotationBase) => boolean): AnnotationBase[];
    /**
     * Converts an XFDF annotation element into an annotation object.
     * Extracts the attributes from the XFDF element and maps them to annotation object properties.
     *
     * @param element The XFDF element representing an annotation.
     * @returns The corresponding annotation object.
     */
    private annotationFromXFDF;
    /**
     * Converts an XFDF widget field element into a widget field object.
     *
     * @param element The XFDF field element representing a widget field.
     * @returns The corresponding widget field object.
     */
    private widgetFieldFromXFDF;
}