import fs from 'fs';
export declare const appRootDir: string;
export declare const assetsFolderRoot: string;
export declare const readJsonFile: <T>(filePath: string) => string | T | undefined;
export declare const readFile: (filePath: string) => string | undefined;
export declare const readFiles: (directory: string) => string[];
export declare const writeFile: (filePath: string, content: string) => void;
export declare const writeStream: (filePath: string) => fs.WriteStream;
export declare const checkDir: (filePath: string) => void;
export declare const checkFile: (filePath: string) => boolean;
export declare const copyFile: (from: string, to: string) => void;
export declare const localPath: (filePath: string) => string;
export declare const getFilesListDeep: (dirPath: string, arrayOfFiles?: string[]) => string[];
export declare const dirSize: (directory: string) => Promise<string>;
export declare const cacheSize: () => Promise<[AppError | null, string | undefined]>;
export declare const cachePreview: () => Promise<[AppError | undefined, {
    [folder: string]: string;
} | undefined]>;