// David Eberly, Geometric Tools, Redmond WA 98052
// Copyright (c) 1998-2020
// Distributed under the Boost Software License, Version 1.0.
// https://www.boost.org/LICENSE_1_0.txt
// https://www.geometrictools.com/License/Boost/LICENSE_1_0.txt
// Version: 4.0.2019.08.13

#pragma once

#include <Mathematics/DistLine3Triangle3.h>
#include <Mathematics/DistPointTriangle.h>
#include <Mathematics/Ray.h>

namespace WwiseGTE
{
    template <typename Real>
    class DCPQuery<Real, Ray3<Real>, Triangle3<Real>>
    {
    public:
        struct Result
        {
            Real distance, sqrDistance;
            Real rayParameter, triangleParameter[3];
            Vector3<Real> closestPoint[2];
        };

        Result operator()(Ray3<Real> const& ray, Triangle3<Real> const& triangle)
        {
            Result result;

            Line3<Real> line(ray.origin, ray.direction);
            DCPQuery<Real, Line3<Real>, Triangle3<Real>> ltQuery;
            auto ltResult = ltQuery(line, triangle);

            if (ltResult.lineParameter >= (Real)0)
            {
                result.distance = ltResult.distance;
                result.sqrDistance = ltResult.sqrDistance;
                result.rayParameter = ltResult.lineParameter;
                result.triangleParameter[0] = ltResult.triangleParameter[0];
                result.triangleParameter[1] = ltResult.triangleParameter[1];
                result.triangleParameter[2] = ltResult.triangleParameter[2];
                result.closestPoint[0] = ltResult.closestPoint[0];
                result.closestPoint[1] = ltResult.closestPoint[1];
            }
            else
            {
                DCPQuery<Real, Vector3<Real>, Triangle3<Real>> ptQuery;
                auto ptResult = ptQuery(ray.origin, triangle);
                result.distance = ptResult.distance;
                result.sqrDistance = ptResult.sqrDistance;
                result.rayParameter = (Real)0;
                result.triangleParameter[0] = ptResult.parameter[0];
                result.triangleParameter[1] = ptResult.parameter[1];
                result.triangleParameter[2] = ptResult.parameter[2];
                result.closestPoint[0] = ray.origin;
                result.closestPoint[1] = ptResult.closest;
            }
            return result;
        }
    };
}