/// <reference types="node" />
import { Readable, Writable } from 'stream';
export declare class FileSystemService {
    private readonly fs;
    constructor(fs: {
        createReadStream: (filePath: string) => Readable;
        createWriteStream: (filePath: string) => Writable;
        stat: (filePath: string, callback: (err: Error) => void) => void;
    });
    exists(filePath: string): Promise<boolean>;
    createReadableStream(filePath: string): Readable;
    createWritableStream(filePath: string): Writable;
}