/**
 * Copyright (c) 2014-present, Facebook, Inc. All rights reserved.
 *
 * This source code is licensed under the BSD-style license found in the
 * LICENSE file in the root directory of this source tree. An additional grant
 * of patent rights can be found in the PATENTS file in the same directory.
 *
 * @flow
 * @format
 */
'use strict';

declare module 'graceful-fs' {
  declare class Stats {
    dev: number;
    ino: number;
    mode: number;
    nlink: number;
    uid: number;
    gid: number;
    rdev: number;
    size: number;
    blksize: number;
    blocks: number;
    atime: Date;
    mtime: Date;
    ctime: Date;

    isFile(): boolean;
    isDirectory(): boolean;
    isBlockDevice(): boolean;
    isCharacterDevice(): boolean;
    isSymbolicLink(): boolean;
    isFIFO(): boolean;
    isSocket(): boolean;
  }

  declare class FSWatcher extends events$EventEmitter {
    close(): void;
  }

  declare class ReadStream extends stream$Readable {
    close(): void;
  }

  declare class WriteStream extends stream$Writable {
    close(): void;
  }

  declare function gracefulify(fs: Object): void;
  declare function rename(
    oldPath: string,
    newPath: string,
    callback?: (err: ?Error) => void,
  ): void;
  declare function renameSync(oldPath: string, newPath: string): void;
  declare function ftruncate(
    fd: number,
    len: number,
    callback?: (err: ?Error) => void,
  ): void;
  declare function ftruncateSync(fd: number, len: number): void;
  declare function truncate(
    path: string,
    len: number,
    callback?: (err: ?Error) => void,
  ): void;
  declare function truncateSync(path: string, len: number): void;
  declare function chown(
    path: string,
    uid: number,
    gid: number,
    callback?: (err: ?Error) => void,
  ): void;
  declare function chownSync(path: string, uid: number, gid: number): void;
  declare function fchown(
    fd: number,
    uid: number,
    gid: number,
    callback?: (err: ?Error) => void,
  ): void;
  declare function fchownSync(fd: number, uid: number, gid: number): void;
  declare function lchown(
    path: string,
    uid: number,
    gid: number,
    callback?: (err: ?Error) => void,
  ): void;
  declare function lchownSync(path: string, uid: number, gid: number): void;
  declare function chmod(
    path: string,
    mode: number | string,
    callback?: (err: ?Error) => void,
  ): void;
  declare function chmodSync(path: string, mode: number | string): void;
  declare function fchmod(
    fd: number,
    mode: number | string,
    callback?: (err: ?Error) => void,
  ): void;
  declare function fchmodSync(fd: number, mode: number | string): void;
  declare function lchmod(
    path: string,
    mode: number | string,
    callback?: (err: ?Error) => void,
  ): void;
  declare function lchmodSync(path: string, mode: number | string): void;
  declare function stat(
    path: string,
    callback?: (err: ?Error, stats: Stats) => any,
  ): void;
  declare function statSync(path: string): Stats;
  declare function fstat(
    fd: number,
    callback?: (err: ?Error, stats: Stats) => any,
  ): void;
  declare function fstatSync(fd: number): Stats;
  declare function lstat(
    path: string,
    callback?: (err: ?Error, stats: Stats) => any,
  ): void;
  declare function lstatSync(path: string): Stats;
  declare function link(
    srcpath: string,
    dstpath: string,
    callback?: (err: ?Error) => void,
  ): void;
  declare function linkSync(srcpath: string, dstpath: string): void;
  declare function symlink(
    srcpath: string,
    dtspath: string,
    type?: string,
    callback?: (err: ?Error) => void,
  ): void;
  declare function symlinkSync(
    srcpath: string,
    dstpath: string,
    type: string,
  ): void;
  declare function readlink(
    path: string,
    callback: (err: ?Error, linkString: string) => void,
  ): void;
  declare function readlinkSync(path: string): string;
  declare function realpath(
    path: string,
    cache?: Object,
    callback?: (err: ?Error, resolvedPath: string) => void,
  ): void;
  declare function realpathSync(path: string, cache?: Object): string;
  declare function unlink(path: string, callback?: (err: ?Error) => void): void;
  declare function unlinkSync(path: string): void;
  declare function rmdir(path: string, callback?: (err: ?Error) => void): void;
  declare function rmdirSync(path: string): void;
  declare function mkdir(
    path: string,
    mode?: number,
    callback?: (err: ?Error) => void,
  ): void;
  declare function mkdirSync(path: string, mode?: number): void;
  declare function readdir(
    path: string,
    callback?: (err: ?Error, files: Array<string>) => void,
  ): void;
  declare function readdirSync(path: string): Array<string>;
  declare function close(fd: number, callback?: (err: ?Error) => void): void;
  declare function closeSync(fd: number): void;
  declare function open(
    path: string,
    flags: string,
    mode?: number,
    callback?: (err: ?Error, fd: number) => void,
  ): void;
  declare function openSync(path: string, flags: string, mode?: number): number;
  declare function utimes(
    path: string,
    atime: number,
    mtime: number,
    callback?: (err: ?Error) => void,
  ): void;
  declare function utimesSync(path: string, atime: number, mtime: number): void;
  declare function futimes(
    fd: number,
    atime: number,
    mtime: number,
    callback?: (err: ?Error) => void,
  ): void;
  declare function futimesSync(fd: number, atime: number, mtime: number): void;
  declare function fsync(fd: number, callback?: (err: ?Error) => void): void;
  declare function fsyncSync(fd: number): void;
  declare var write: (
    fd: number,
    buffer: Buffer,
    offset: number,
    length: number,
    position?: mixed,
    callback?: (err: ?Error, write: number, str: string) => void,
  ) =>
    | void
    | ((
        fd: number,
        data: mixed,
        position?: mixed,
        encoding?: string,
        callback?: (err: ?Error, write: number, str: string) => void,
      ) => void);
  declare var writeSync: (
    fd: number,
    buffer: Buffer,
    offset: number,
    length: number,
    position?: number,
  ) =>
    | number
    | ((
        fd: number,
        data: mixed,
        position?: mixed,
        encoding?: string,
      ) => number);
  declare function read(
    fd: number,
    buffer: Buffer,
    offset: number,
    length: number,
    position: ?number,
    callback?: (err: ?Error, bytesRead: number, buffer: Buffer) => void,
  ): void;
  declare function readSync(
    fd: number,
    buffer: Buffer,
    offset: number,
    length: number,
    position: number,
  ): number;
  declare function readFile(
    filename: string,
    callback: (err: ?Error, data: Buffer) => void,
  ): void;
  declare function readFile(
    filename: string,
    encoding: string,
    callback: (err: ?Error, data: string) => void,
  ): void;
  declare function readFile(
    filename: string,
    options: {encoding: string, flag?: string},
    callback: (err: ?Error, data: string) => void,
  ): void;
  declare function readFile(
    filename: string,
    options: {flag?: string},
    callback: (err: ?Error, data: Buffer) => void,
  ): void;
  declare function readFileSync(filename: string, _: void): Buffer;
  declare function readFileSync(filename: string, encoding: string): string;
  declare function readFileSync(
    filename: string,
    options: {encoding: string, flag?: string},
  ): string;
  declare function readFileSync(
    filename: string,
    options: {encoding?: void, flag?: string},
  ): Buffer;
  declare function writeFile(
    filename: string,
    data: Buffer | string,
    options?: Object | string,
    callback?: (err: ?Error) => void,
  ): void;
  declare function writeFileSync(
    filename: string,
    data: Buffer | string,
    options?: Object | string,
  ): void;
  declare function appendFile(
    filename: string,
    data: string | Buffer,
    options?: Object,
    callback?: (err: ?Error) => void,
  ): void;
  declare function appendFileSync(
    filename: string,
    data: string | Buffer,
    options?: Object,
  ): void;
  declare function watchFile(
    filename: string,
    options?: Object,
    listener?: (curr: Stats, prev: Stats) => void,
  ): void;
  declare function unwatchFile(
    filename: string,
    listener?: (curr: Stats, prev: Stats) => void,
  ): void;
  declare function watch(
    filename: string,
    options?: Object,
    listener?: (event: string, filename: string) => void,
  ): FSWatcher;
  declare function exists(
    path: string,
    callback?: (exists: boolean) => void,
  ): void;
  declare function existsSync(path: string): boolean;
  declare function access(
    path: string,
    mode?: any,
    callback?: (err: ?Error) => void,
  ): void;
  declare function accessSync(path: string, mode?: any): void;
  declare function createReadStream(path: string, options?: Object): ReadStream;
  declare function createWriteStream(
    path: string,
    options?: Object,
  ): WriteStream;

  declare var F_OK: number;
  declare var R_OK: number;
  declare var W_OK: number;
  declare var X_OK: number;
}