#include "Cyl.h"
#include "util/Solver.h"
#include <math.h>
#include <iostream>
using namespace std;

#define FP_EQUAL(x,y) (fabs((x)-(y)) < 0.000001)

Cyl::Cyl(double bottom_radius, double top_radius, double height)
{
    m_bottom_radius = fabs(bottom_radius);
    m_bottom_radius_2 = bottom_radius * bottom_radius;
    m_top_radius = fabs(top_radius);
    m_top_radius_2 = top_radius * top_radius;
    m_height = fabs(height);
    if (m_height == 0.0)
        m_height = 1.0;
}

Shape::IntersectList Cyl::intersect(const Ray & ray)
{
    Ray ray_inv = m_inverse.transform_ray(ray);

    IntersectList res;
    /*
     * Ray equation:   R = R0 + tRd
     *                 x = R0x + tRdx
     *                 y = R0y + tRdy
     *                 z = R0z + tRdz
     * Side equation:  x^2 + y^2 = 
     * Combined:       
     */

    return res;
}

Vector Cyl::getNormalAt(const Vector & pt)
{
    Vector local_pt = m_inverse.transform_point(pt);

    Vector normal;

    if      ( FP_EQUAL(local_pt[2],  0.0) && m_bottom_radius > 0.0 )
    {
        normal = Vector(0, 0, -1);
    }
    else if ( FP_EQUAL(local_pt[2], m_height) && m_top_radius > 0.0 )
    {
        normal = Vector(0, 0, 1);
    }
    else
    {
    }

    return m_transform.transform_normal(normal);
}