#include <iostream>
#include <GL/glew.h>
#include <GL/freeglut.h>
#include <GL/glext.h>
#include <cmath>

#include "hsv.h"

using namespace std;

struct point{
    GLfloat x,y,z;
};

struct color{
    GLfloat r,g,b;
};

point * Points;
color * Colors;

GLfloat XRot, YRot, ZRot;

int TotalPoints = 100;
float dtheta = 2*M_PI/ float(TotalPoints/2);

void display() {
    int i;

    glLoadIdentity();
    glRotatef(XRot, 1,0,0);
    glRotatef(YRot, 0,1,0);
    glRotatef(ZRot, 0,0,1);


    glClear(GL_COLOR_BUFFER_BIT);
    glColor3f(0,0,0);
    glBegin(GL_LINE_LOOP);
       for (i=0; i<TotalPoints; i++) {
           glColor3f(Colors[i].r, Colors[i].g, Colors[i].b);
           glVertex3f(Points[i].x,Points[i].y, Points[i].z);
       }
    glEnd();

    glFlush();
    return;
}

void MakeCardioid() {
     float theta;
     int i = 0;
     float a = 0.5;
     hsv color1;
     rgb color2;

     Points = new point[TotalPoints];
     theta = 0;
     for (i=0; i < TotalPoints; i++) {
         Points[i].x = a*(2*cos(theta) - cos(2.0*theta)); 
         Points[i].y = a*(2*sin(theta) - sin(2.0*theta)); 
	 Points[i].z = a*sqrt(8.0)*cos(theta/2.0);
	 theta += dtheta;
     }

     Colors = new color[TotalPoints];
     theta = 0;
     color1.s = 1;
     color1.v = 1;
     for (i=0; i < TotalPoints; i++) {
	 theta += dtheta/2;
	 color1.h = theta * 180.0/M_PI;
	 color2 = hsv2rgb(color1);
	 Colors[i].r = color2.r;
	 Colors[i].g = color2.g;
	 Colors[i].b = color2.b;
     }

     return;
}

void reset () {
    XRot = 0;
    YRot = 0;
    ZRot = 0;

    return;
}

void setup() {
     reset();
     glClearColor(1.0,1.0, 1.0, 0.0);
     MakeCardioid();
     return;
}


void  keypress (unsigned char key, int x, int y) {
   switch (key) {
     case 'r':
        reset();
	break;
     case 'x':
        XRot += 10;
	break;
     case 'y':
        YRot += 10;
	break;
     case 'z':
        ZRot += 10;
	break;
     case 'q':
          exit(0);
   }
   glutPostRedisplay();
   return;
}

void resize(int w, int h) {
   glViewport(0, 0, w, h);
   glMatrixMode(GL_PROJECTION);
   glLoadIdentity();
   glOrtho(-1.5, 1.5, -1.5, 1.5, 1.5, -1.5);
   glMatrixMode(GL_MODELVIEW);
   glLoadIdentity();

   return;
}

int main(int argc, char * argv[]) {
   glutInit(&argc, argv);

   glutInitContextVersion(3, 0);
   glutInitContextProfile(GLUT_COMPATIBILITY_PROFILE);

   glutInitDisplayMode(GLUT_SINGLE | GLUT_RGBA);
   glutInitWindowSize(500, 500);
   glutCreateWindow("simplePreVBO");
   glutDisplayFunc(display);
   glutReshapeFunc(resize);
   glutKeyboardFunc(keypress);

   glewExperimental = GL_TRUE;
   glewInit();

   setup();

   glutMainLoop();
}