Vector2Es6.js

const { Vector2, isVector2 } = (
    () => {
        class _Vector2 {
            constructor(x, y) {
                let data = {
                    x: x || 0,
                    y: y || 0
                };

                const checkParmeterType = parameters => {
                    if (parameters[0] instanceof _Vector2) {
                        return parameters[0].get();
                    }
                    if (typeof parameters[0] === 'number' && typeof parameters[1] === 'number') {
                        return {
                            x: parameters[0],
                            y: parameters[1]
                        }
                    }
                    if (typeof parameters[0] === 'number') {
                        return {
                            x: parameters[0],
                            y: parameters[0]
                        };
                    }
                    return {
                        x: parameters[0],
                        y: parameters[1]
                    };
                }

                /* get */
                this.get = () => data;
                this.getX = () => data.x;
                this.getY = () => data.y;

                /* set */
                this.set = (...parameters) => {
                    let pData = checkParmeterType(parameters);

                    data.x = pData.x === undefined ? data.x : pData.x;
                    data.y = pData.y === undefined ? data.y : pData.y;
                    return this;
                }
                this.setX = x => data.x = x;
                this.setY = y => data.y = y;

                /* add */
                this.add = (...parameters) => {
                    let pData = checkParmeterType(parameters);

                    data.x += pData.x === undefined ? data.x : pData.x;
                    data.y += pData.y === undefined ? data.y : pData.y;
                    return this;
                }
                this.addX = x => data.x += x;
                this.addY = y => data.y += y;

                /* sub */
                this.sub = (...parameters) => {
                    let pData = checkParmeterType(parameters);

                    data.x -= pData.x === undefined ? data.x : pData.x;
                    data.y -= pData.y === undefined ? data.y : pData.y;
                    return this;
                }
                this.subX = x => data.x -= x;
                this.subY = y => data.y -= y;

                /* multiply */
                this.multiply = (...parameters) => {
                    let pData = checkParmeterType(parameters);

                    data.x *= pData.x === undefined ? 1 : pData.x;
                    data.y *= pData.y === undefined ? 1 : pData.y;
                    return this;
                }
                this.multiplyX = x => data.x *= x;
                this.multiplyY = y => data.y *= y;

                /* divide */
                this.divide = (...parameters) => {
                    let pData = checkParmeterType(parameters);

                    data.x /= pData.x === undefined ? 1 : pData.x;
                    data.y /= pData.y === undefined ? 1 : pData.y;
                    return this;
                }
                this.divideX = x => data.x /= x;
                this.devideY = y => data.y /= y;

                /* distance */
                this.distance = () => Math.sqrt(data.x * data.x + data.y * data.y);

                /* normalize */
                this.normalize = () => {
                    let distance = this.distance() || 1;
                    this.devide(distance.x, distance.y);
                    return this;
                }
                this.getNormalized = () => {
                    let vec2 = new _Vector2(data.x, data.y);
                    return vec2.normalize();
                }

                /* dot product */
                this.dot = (...parameters) => {
                    let pData = checkParmeterType(parameters);
                    return data.x * pData.x + data.y * pData.y;
                }

                this.equal = (...parameters) => {
                    let pData = checkParmeterType(parameters);
                    return data.x === pData.x && data.y === pData.y;
                }
                
                this.clone = () => new _Vector2(data.x, data.y);
            }
        }
        return {
            isVector2: e => e instanceof _Vector2,
            Vector2: (x, y) => new _Vector2(x, y)
        };
    }
)();