import { _decorator, Component, Node, Rect, Sprite, Vec2 } from 'cc';
const { ccclass, property } = _decorator;


@_decorator.ccclass('ScrollUV')
export class ScrollUV extends Component {

    @property({ type: Sprite })
    sprite: Sprite = null;

    @property
    public scrollSpeed = new Vec2(0.1, 0); // 横向滚动速度，默认每帧偏移0.1

    private baseUvs: number[] = [];

    onLoad() {
        if (!this.sprite) {
            this.sprite = this.getComponent(Sprite);
        }

        // 保存原始 UV 数据
        const spriteFrame = this.sprite.spriteFrame;
        if (spriteFrame) {
            const uvs = spriteFrame.uv;
            this.baseUvs = [...uvs];
        }

    }

    update(deltaTime: number) {
        let offsetX = (Date.now() * this.scrollSpeed.x) % 1;
        let offsetY = (Date.now() * this.scrollSpeed.y) % 1;

        // const rect = new Rect(offsetX, 0, 1, 1); // 横向滚动
        // this.sprite.spriteFrame.setOffset(rect);

        // const newUvs = [...this.baseUvs];

        // for (let i = 0; i < newUvs.length; i += 4) {
        //     newUvs[i] = (this.baseUvs[i] + offsetX) % 1;
        //     newUvs[i + 1] = (this.baseUvs[i + 1] + offsetY) % 1;
        //     newUvs[i + 2] = (this.baseUvs[i + 2] + offsetX) % 1;
        //     newUvs[i + 3] = (this.baseUvs[i + 3] + offsetY) % 1;
        // }

        // // 注意：需要重新创建 SpriteFrame 或者使用自定义材质来支持动态 UV
        // // 这里我们尝试直接修改 spriteFrame.uv（仅限非图集）
        // const sf = this.sprite.spriteFrame;
        // if (sf && !sf.isRotated()) {
        //     sf.uv = newUvs;
        //     this.sprite.spriteFrame = null;
        //     this.sprite.spriteFrame = sf;
        // }
    }
}