import * as matrix from 'zrender/src/core/matrix';

function createTransform(zoom) {
    let transform = matrix.create();
    transform = matrix.scale(matrix.create(), transform, [zoom.scale, zoom.scale]);
    transform = matrix.translate(matrix.create(), transform, [zoom.offsetX, zoom.offsetY]);
    return transform;
}

function createBoundingRect(view) {
    let rect = view.getBoundingRect();
    let scale = view.scale[0];
    let offsetX = view.position[0];
    let offsetY = view.position[1];
    rect.width = rect.width * scale;
    rect.height = rect.height * scale;
    rect.x = rect.x * scale + offsetX;
    rect.y = rect.y * scale + offsetY;
    return rect;
}

class ZoomHandle {
    constructor(painter) {
        this.zr = painter.jmap.getZr();
        this.parentLevel = painter.parentLevel;

        this.rect = { x: 0, y: 0, width: this.zr.getWidth(), height: this.zr.getHeight() };
        this.transform = createTransform({ scale: 1, offsetX: 0, offsetY: 0 });
    }

    checkVisible(view) {
        return createBoundingRect(view).intersect(this.rect);
    }

    revisibleView(view) {
        if (this.checkVisible(view)) {
            view.show();
        } else {
            view.hide();
        }

        view.dirty();
    }

    transformView(view) {
        if (view) {
            view.transform = this.transform;
            view.decomposeTransform();
            this.revisibleView(view);
        }

        return view;
    }

    transformAll() {
        this.parentLevel.eachChild((level) => {
            level.eachChild((view) => {
                this.transformView(view);
            });
        });
    }

    revisibleAll() {
        this.parentLevel.eachChild((level) => {
            level.eachChild((view) => {
                this.revisibleView(view);
            });
        });
    }

    updateTransform(zoom) {
        this.transform = createTransform(zoom);
        this.transformAll();
    }
}

export default ZoomHandle;