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package com.dkstrong.transport.g3d.shape;

import com.badlogic.gdx.math.Intersector;
import com.badlogic.gdx.math.MathUtils;
import com.badlogic.gdx.math.Matrix4;
import com.badlogic.gdx.math.Quaternion;
import com.badlogic.gdx.math.Vector3;
import com.badlogic.gdx.math.collision.BoundingBox;
import com.badlogic.gdx.math.collision.Ray;

public class BoxTest {

    public static void main(String[] args) {
        // transform for when the box isnt rotated
        Matrix4 identitydTransform = new Matrix4(
            new Vector3(),
            new Quaternion(),
            new Vector3(1,1,1)
        );

        // tranform for when box is rotated 90 degress (this is the problem!)
        Matrix4 rotatedTransform = new Matrix4(
            new Vector3(),
            new Quaternion().setFromAxisRad(new Vector3(0,1,0), MathUtils.PI/2f),
            new Vector3(1,1,1)
        );

        Matrix4 identityTransformInverse = identitydTransform.cpy().inv();
        Matrix4 rotatedTransformInverse = rotatedTransform.cpy().inv();

        // bounding box is a rectangle shape, so rotating creates problems
        BoundingBox bb = new BoundingBox(
            new Vector3(-5,-10,-10),
            new Vector3(5, 10, 10)
        );

        // ray goes from top of world and goes down
        Ray ray = new Ray(
            new Vector3(0,20,9), // the ray position means its going to hit the long end of the rectangle
            new Vector3(0,-1,0));

        Ray ray2 = new Ray(
            new Vector3(9,20,0), // since box is rotated the person would click somewhere else..
            new Vector3(0,-1,0));

        Ray rayForIdentiy = ray.cpy().mul(identityTransformInverse);
        Ray rayForRotated = ray2.cpy().mul(rotatedTransformInverse);

        Vector3 bbCenter = bb.getCenter(new Vector3());
        Vector3 bbDimensions = bb.getDimensions(new Vector3());
        boolean isHit;
        isHit = Intersector.intersectRayBoundsFast(rayForIdentiy, bbCenter, bbDimensions);
        System.out.println("works if transform is identity: "+isHit); // true
        isHit = Intersector.intersectRayBoundsFast(rayForRotated, bbCenter, bbDimensions);
        System.out.println("works if transform is rotated: "+isHit); // true

    }
}