using UnityEngine;

//struct purpose: define an axis alligned bounding box
[System.Serializable]
public struct AABB
{
    public Vector3 origin; // lowest point on all 3 axis of the AABB
    public float width;
    public float height;
    public float length;

    //Summary:
    //     Shorthand for writing AABB(new Vector3.zero, 0, 0, 0).
    public static AABB zero { get; } = new AABB(Vector3.zero, 0, 0, 0);

    /// <summary> Forms an AABB out of the provided data.If allow_negative_size is true, adjusts the AABB to make sure the size values are not negative </summary>
    public AABB(Vector3 origin, float width, float height, float length)
    {
        float origin_x = origin.x;
        float origin_y = origin.y;
        float origin_z = origin.z;

        // If we get provided negative size for the axis, offset the origin by the size and absolute the size
        if (width < 0)
        {
            this.width = -width;
            origin_x += width;
        }
        else
            this.width = width;

        if (height < 0)
        {
            this.height = -height;
            origin_y += height;
        }
        else
            this.height = height;

        if (length < 0)
        {
            this.length = -length;
            origin_z += length;
        }
        else
            this.length = length;

        this.origin = new Vector3(origin_x, origin_y, origin_z);
    }

    /// <summary> Forms an AABB out of the sphere origin and sphere radius </summary>
    public AABB(Vector3 sphere_origin, float sphere_radius)
    {
        origin = sphere_origin - new Vector3(sphere_radius, sphere_radius, sphere_radius);
        width = sphere_radius * 2;
        height = width;
        length = width;
    }

    /// <summary> Returns the lowest point on all axis </summary>
    public Vector3 AABB_Min()
    {
        return origin;
    }

    /// <summary> Returns the highest point on all axis </summary>
    public Vector3 AABB_Max()
    {
        return origin + new Vector3(width, height, length);
    }
}