const { ccclass } = cc._decorator;

@ccclass
export default class Shake extends cc.ActionInterval {
	private _init: boolean = false;
	private _initial_x: number = 0;
	private _initial_y: number = 0;
	private _strength_x: number = 0;
	private _strength_y: number = 0;

	/**
	 *  建立抖動動畫
	 * @param {number} duration     動畫持續時長
	 * @param {number} strength_x   抖動幅度： x方向
	 * @param {number} strength_y   抖動幅度： y方向
	 * @returns {Shake}
	 */
	public static create(duration: number, strength_x: number, strength_y: number): Shake {
		let act: Shake = new Shake();
		act.initWithDuration(duration, strength_x, strength_y);
		return act;
	}

	public initWithDuration(duration: number, strength_x: number, strength_y: number): boolean {
		cc.ActionInterval.prototype['initWithDuration'].apply(this, arguments);
		this._strength_x = strength_x;
		this._strength_y = strength_y;
		return true;
	}

	public fgRangeRand(min: number, max: number): number {
		let rnd: number = Math.random();
		return rnd * (max - min) + min;
	}

	public update(time: number): void {
		let randx = this.fgRangeRand(-this._strength_x, this._strength_x);
		let randy = this.fgRangeRand(-this._strength_y, this._strength_y);
		this.getTarget()?.setPosition(randx + this._initial_x, randy + this._initial_y);
	}

	public startWithTarget(target: cc.Node): void {
		cc.ActionInterval.prototype['startWithTarget'].apply(this, arguments);
		if (!this._init) {
			this._init = true;
			this._initial_x = target.x;
			this._initial_y = target.y;
		}
	}

	public stop(): void {
		this.getTarget()?.setPosition(new cc.Vec2(this._initial_x, this._initial_y));
		cc.ActionInterval.prototype['stop'].apply(this);
	}
}