declare namespace TWEEN {
    export let REVISION: string;

    export function getAll(): Tween[];

    export function removeAll(): void;

    export function add(tween: Tween): void;

    export function remove(tween: Tween): void;

    export function update(time?: number): boolean;

    export class Tween {
        constructor(object?: any);

        to(properties: any, duration: number): Tween;

        start(time?: number): Tween;

        stop(): Tween;

        delay(amount: number): Tween;

        easing(easing: (k: number) => number): Tween;

        interpolation(interpolation: (v: number[], k: number) => number): Tween;

        chain(...tweens: Tween[]): Tween;

        onStart(callback: (object?: any) => void): Tween;

        onUpdate(callback: (object?: any) => void): Tween;

        onComplete(callback: (object?: any) => void): Tween;

        update(time: number): boolean;

        repeat(times: number): Tween;

        yoyo(enable: boolean): Tween;
    }

    export let Easing: TweenEasing;
    export let Interpolation: TweenInterpolation;
}

interface TweenEasing {
    Linear: {
        None(k: number): number;
    };
    Quadratic: {
        In(k: number): number;
        Out(k: number): number;
        InOut(k: number): number;
    };
    Cubic: {
        In(k: number): number;
        Out(k: number): number;
        InOut(k: number): number;
    };
    Quartic: {
        In(k: number): number;
        Out(k: number): number;
        InOut(k: number): number;
    };
    Quintic: {
        In(k: number): number;
        Out(k: number): number;
        InOut(k: number): number;
    };
    Sinusoidal: {
        In(k: number): number;
        Out(k: number): number;
        InOut(k: number): number;
    };
    Exponential: {
        In(k: number): number;
        Out(k: number): number;
        InOut(k: number): number;
    };
    Circular: {
        In(k: number): number;
        Out(k: number): number;
        InOut(k: number): number;
    };
    Elastic: {
        In(k: number): number;
        Out(k: number): number;
        InOut(k: number): number;
    };
    Back: {
        In(k: number): number;
        Out(k: number): number;
        InOut(k: number): number;
    };
    Bounce: {
        In(k: number): number;
        Out(k: number): number;
        InOut(k: number): number;
    };
}

interface TweenInterpolation {
    Linear(v: number[], k: number): number;

    Bezier(v: number[], k: number): number;

    CatmullRom(v: number[], k: number): number;

    Utils: {
        Linear(p0: number, p1: number, t: number): number;
        Bernstein(n: number, i: number): number;
        Factorial(n): number;
        CatmullRom(p0, p1, p2, p3, t): number;
    };
}