/// <reference types="node" />

import { Stream } from "stream";

type Appendable = NodeJS.ReadableStream | NodeJS.WritableStream | Buffer | string | NextFunction;
type NextFunction = (next: (stream: Appendable) => any) => any;

interface Options {
    maxDataSize?: number | undefined;
    pauseStreams?: boolean | undefined;
}

declare class CombinedStream extends Stream implements Options {
    readonly writable: boolean;
    readonly readable: boolean;
    readonly dataSize: number;
    maxDataSize: number;
    pauseStreams: boolean;
    append(stream: Appendable): this;
    write(data: any): void;
    pause(): void;
    resume(): void;
    end(): void;
    destroy(): void;

    // private properties
    _released: boolean;
    // @TODO it should be a type of Array<'delayed-stream' instance | Buffer | string>
    _streams: Array<Stream | Buffer | string>;
    _currentStream: Stream | Buffer | string | null;
    _getNext(): void;
    _pipeNext(): void;
    _handleErrors(stream: NodeJS.EventEmitter): void;
    _reset(): void;
    _checkDataSize(): void;
    _updateDataSize(): void;
    _emitError(error: Error): void;

    // events
    on(event: "close" | "end" | "resume" | "pause", cb: () => void): this;
    on(event: "error", cb: (err: Error) => void): this;
    on(event: "data", cb: (data: any) => void): this;
    once(event: "close" | "end" | "resume" | "pause", cb: () => void): this;
    once(event: "error", cb: (err: Error) => void): this;
    once(event: "data", cb: (data: any) => void): this;

    static create(options?: Options): CombinedStream;
    static isStreamLike(stream: any): stream is Stream;
}

export = CombinedStream;