import { Attribute } from "../geometry/Attribute.ts";
import { Geometry } from "../geometry/Geometry.ts";
import { LineMaterial } from "../materials/LineMaterial.ts";
import { LineSegments } from "../objects/LineSegments.ts";

interface BoxLikeObject {
	geometry?: {
		boundingBox?: {
			min: { x: number; y: number; z: number };
			max: { x: number; y: number; z: number };
		};
	};
}

/** Draws a wireframe box around an object's bounding box. */
export class BoxHelper extends LineSegments {
	override type = "BoxHelper";

	#object: BoxLikeObject;

	constructor(object: BoxLikeObject, color = 0xffff00) {
		const geometry = new Geometry();
		const material = new LineMaterial({ color });

		// 12 edges x 2 vertices = 24 positions (placeholder, filled by update())
		geometry.setAttribute(
			"position",
			new Attribute(new Float32Array(24 * 3), 3),
		);

		super(geometry, material);

		this.#object = object;
		this.update();
	}

	/** Recomputes the wireframe from the object's bounding box. */
	update(): void {
		this.setFromObject(this.#object);
	}

	setFromObject(object: BoxLikeObject): this {
		if (!object?.geometry) return this;

		const box = object.geometry.boundingBox;
		if (!box) return this;

		const min = box.min;
		const max = box.max;

		// 8 corners of the box
		const x0 = min.x;
		const y0 = min.y;
		const z0 = min.z;
		const x1 = max.x;
		const y1 = max.y;
		const z1 = max.z;

		// 12 edges as line segment pairs (24 vertices)
		const positions = new Float32Array([
			// bottom face
			x0,
			y0,
			z0,
			x1,
			y0,
			z0,
			x1,
			y0,
			z0,
			x1,
			y0,
			z1,
			x1,
			y0,
			z1,
			x0,
			y0,
			z1,
			x0,
			y0,
			z1,
			x0,
			y0,
			z0,
			// top face
			x0,
			y1,
			z0,
			x1,
			y1,
			z0,
			x1,
			y1,
			z0,
			x1,
			y1,
			z1,
			x1,
			y1,
			z1,
			x0,
			y1,
			z1,
			x0,
			y1,
			z1,
			x0,
			y1,
			z0,
			// verticals
			x0,
			y0,
			z0,
			x0,
			y1,
			z0,
			x1,
			y0,
			z0,
			x1,
			y1,
			z0,
			x1,
			y0,
			z1,
			x1,
			y1,
			z1,
			x0,
			y0,
			z1,
			x0,
			y1,
			z1,
		]);

		this.geometry?.setAttribute("position", new Attribute(positions, 3));

		return this;
	}

	dispose(): void {
		this.geometry?.dispose();
	}
}