import { FileRequest, FileCheckoutResultValue } from '../core/event-adapter';
export interface FileDownloadProgress {
    fileUnique: bigint;
    fileName: string;
    progress: number;
}
export interface DownloadedFile {
    data: Blob;
    name?: string;
}
export declare class FileDownloadManager {
    private dataChannel;
    private onFileTransferApply?;
    private onProgress?;
    private onReceivedFile?;
    private fileReceivedMap;
    private cdPromiseMap;
    private coPromiseMap;
    /**
     * use the FileSystemAccess API to download file.
     *
     * @default false
     */
    private useFileSystemAPI;
    /**
     * When the file size is less than the threshold (byte-based), the original method will be used.
     *
     * @default 524288000 - 500 MB
     */
    private fileSystemAPIThreshold;
    constructor(dataChannel: RTCDataChannel, onFileTransferApply?: ((payload: FileRequest) => void) | undefined, onProgress?: ((payload: FileDownloadProgress) => void) | undefined, onReceivedFile?: ((payload: DownloadedFile) => void) | undefined);
    private handleMessage;
    private removeAllListeners;
    private handleClose;
    private handleFileRequest;
    private emitProgressEvent;
    private handleFileContent;
    private handleFileContentWithOriginalMethod;
    private handleFileContentWithFileSystemAccessAPI;
    private handleFileDownloadDirectory;
    private handleFileCheckout;
    private showSaveFilePicker;
    replyFileTransferApply(fileUnique: bigint, allowed: boolean): void;
    changeDirectory(path?: string): Promise<boolean>;
    checkout(fileName: string): Promise<FileCheckoutResultValue>;
    /**
     * enable File System Access API to download file
     * @param {number} [threshold=524288000] When the file size is less than the threshold (byte-based, default 500 MB), the original method will be used.
     */
    enableFileSystemAccessAPI(threshold?: number): void;
    /**
     * disable File System Access API to download file
     */
    disableFileSystemAccessAPI(): void;
    destroy(): void;
}