import { HttpMediaType } from '@opra/common';
import busboy from 'busboy';
import { EventEmitter } from 'events';
import type { StrictOmit } from 'ts-gems';
import type { HttpContext } from '../http-context.js';
import { LocalFile } from './local-file.js';
/**
 * MultipartReader is responsible for parsing multipart/form-data requests.
 * It uses busboy to stream incoming parts and can handle both fields and files.
 */
export declare class MultipartReader extends EventEmitter {
    protected context: HttpContext;
    protected mediaType?: HttpMediaType | undefined;
    protected _started: boolean;
    protected _finished: boolean;
    protected _cancelled: boolean;
    protected _form: busboy.Busboy;
    protected _items: MultipartReader.Item[];
    protected _stack: MultipartReader.Item[];
    protected tempDirectory: string;
    scope?: string;
    constructor(context: HttpContext, options?: MultipartReader.Options, mediaType?: HttpMediaType | undefined);
    get items(): MultipartReader.Item[];
    /**
     * Retrieves the next item (field or file) from the multipart stream.
     *
     * @returns A promise that resolves to the next item, or undefined if no more items are available.
     * @throws {@link BadRequestError} If a field is unknown or validation fails.
     */
    getNext(): Promise<MultipartReader.Item | undefined>;
    /**
     * Retrieves all items from the multipart stream.
     *
     * @returns A promise that resolves to an array of all items.
     */
    getAll(): Promise<MultipartReader.Item[]>;
    getAll_(): Promise<MultipartReader.Item[]>;
    cancel(): void;
    resume(): void;
    pause(): void;
    /**
     * Purges all temporary files created by the reader.
     *
     * @returns A promise that resolves when all files are purged.
     */
    purge(): Promise<PromiseSettledResult<any>[]>;
}
export declare class MultipartFile extends LocalFile {
    readonly kind = "file";
    readonly field: string;
    constructor(field: string, storedPath: string, options?: LocalFile.Options);
}
export declare namespace MultipartReader {
    interface Options extends StrictOmit<busboy.BusboyConfig, 'headers'> {
        tempDirectory?: string;
        scope?: string;
    }
    interface Field {
        kind: 'field';
        field: string;
        value?: any;
        mimeType?: string;
        encoding?: string;
    }
    type File = MultipartFile;
    type Item = Field | File;
}