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

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

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

class TransformHandle {
	constructor(painter) {
		this.$painter = painter;

		this.parentLevel = painter.getParentLevel();

		this.rect = { x: 0, y: 0, width: 0, height: 0 };

		this.transform = createTransform({ scaleRate: 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();
	}

	// 视图进行缩放/平移
	transformView(view) {
		if (view) {
			view.transform = this.transform;
			view.decomposeTransform();
			this.revisibleView(view);
		}
		// return view;
	}

	// 处理所有视图缩放/平移
	transformAll() {
		this.traverse(this.transformView, this);
	}

	// 重新计算显示图形
	revisibleAll() {
		this.traverse(this.revisibleView, this);
	}

	// 更新偏移量
	updateTransform(opts) {
		this.transform = createTransform(opts);
		this.transformAll();
	}

	// 更新画布尺寸
	updateZrSize(opts) {
		this.rect = { x: 0, y: 0, width: opts.width, height: opts.height };
		this.revisibleAll();
	}

	// 遍历group执行回调
	traverse(cb, context) {
		this.parentLevel.eachChild(level => {
			level.eachChild((view) => {
				cb.call(context, view);
			}, context);
		}, context);
	}
}

export default TransformHandle;