/**
 * Annotation Exporter
 *
 * Flexible annotation export system with pluggable format converters.
 * Supports custom export formats for different use cases.
 */
export interface LabelStudioAnnotation {
    id: number;
    task: number;
    project: number;
    completed_by: {
        id: number;
        email: string;
        first_name: string;
        last_name: string;
    };
    result: Array<{
        from_name: string;
        to_name: string;
        type: string;
        value: any;
    }>;
    created_at: string;
    updated_at: string;
    lead_time?: number;
}
export interface ExportContext {
    projectId: number;
    projectTitle?: string;
    exportedAt: string;
    metadata?: any;
}
/**
 * Export format converter function type
 * Converts Label Studio annotations to custom format
 */
export type FormatConverter<T = any> = (annotations: LabelStudioAnnotation[], context: ExportContext) => T | Promise<T>;
/**
 * Register a custom export format converter
 *
 * @param formatName - Unique format identifier (e.g., "csv", "coco", "yolo")
 * @param converter - Converter function
 *
 * @example
 * registerExportFormat('csv', (annotations, context) => {
 *   const rows = annotations.map(a => ({
 *     id: a.id,
 *     task: a.task,
 *     result: JSON.stringify(a.result)
 *   }))
 *   return Papa.unparse(rows)
 * })
 */
export declare function registerExportFormat<T = any>(formatName: string, converter: FormatConverter<T>): void;
/**
 * Unregister an export format
 */
export declare function unregisterExportFormat(formatName: string): void;
/**
 * Get all registered format names
 */
export declare function getRegisteredFormats(): string[];
/**
 * Export annotations to specified format
 *
 * @param annotations - Label Studio annotations
 * @param format - Export format name
 * @param context - Export context
 * @returns Converted data in requested format
 */
export declare function exportAnnotations<T = any>(annotations: LabelStudioAnnotation[], format: string, context: ExportContext): Promise<T>;
/**
 * Pre-built export formats
 */
export declare class ExportFormats {
    /**
     * Export as JSON (default Label Studio format)
     */
    static json(): FormatConverter<string>;
    /**
     * Export as JSON Lines (one annotation per line)
     */
    static jsonl(): FormatConverter<string>;
    /**
     * Export image classification results as CSV
     */
    static imageClassificationCSV(): FormatConverter<string>;
    /**
     * Export Rank N classification results
     */
    static rankNClassificationCSV(ranks?: number): FormatConverter<string>;
    /**
     * Export object detection results as COCO format
     */
    static coco(): FormatConverter<any>;
    /**
     * Export object detection results as YOLO format
     */
    static yolo(): FormatConverter<Map<number, string>>;
    /**
     * Export NER (Named Entity Recognition) results
     */
    static nerJSON(): FormatConverter<any[]>;
}