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#include<typeinfo>

#include "CGLA/Mat4x4f.h"

#include "CGLA/Mat2x2f.h"

#include "CGLA/Vec2f.h"

#include "CGLA/Vec2i.h"

#include "CGLA/Vec3i.h"

#include "CGLA/Vec3f.h"

#include "CGLA/Vec3Hf.h"

#include <GL/glut.h>

using namespace CGLA;

static void display( void )

{

  // ----------------------------------------

  // 0. Set up viewing parameters

  Vec3f up(0,1,0);             // The direction that is most nearly up ..

  Vec3f eye(3,3,3);            // position of eye 

  Vec3f centre(0,0,0);         // what we are looking at 

  float image_plane_dist = 1;  // distance from eye to image plane.

  // ----------------------------------------

  // 1. Create view coordinate system

  //

  // Note that the args in the cross(.,.) call

  // do not commute

  Vec3f n = centre - eye;

  n.normalize();

  Vec3f u = cross(n,up);

  u.normalize();

  Vec3f v = cross(u,n);

  //----------------------------------------

  // 2. Create matrices

  // Create viewing matrix. We use the basis change method.

  // Notice how the direction of z is flipped. That is because

  // we look down the -z direction

  Mat4x4f mview(Vec3Hf(u,0), Vec3Hf(v,0), Vec3Hf(-n,0), Vec3Hf());

  //Create translation matrix. 

  Mat4x4f mtrans = translation_Mat4x4f(centre-eye);

  // Create projection matrix

  Mat4x4f mpers  = perspective_Mat4x4f(image_plane_dist);

  // Concatenate the translation, viewing and projection matrices

  Mat4x4f m = mpers * mview * mtrans;

  //----------------------------------------

  // 3. Create points 

  Vec3Hf axes[3]={Vec3Hf(2,0,0),Vec3Hf(0,2,0),Vec3Hf(0,0,2)};

  Vec3Hf paxes[3];

  Vec3Hf p[9] ={Vec3Hf(0,0,0), Vec3Hf(1,0,0), Vec3Hf(0,1,0),  

		Vec3Hf(1,1,0), Vec3Hf(0,0,1), Vec3Hf(1,0,1),  

		Vec3Hf(0,1,1), Vec3Hf(1,1,1)};

  Vec3Hf pp[9];

  //----------------------------------------

  // 4. project and dehomogenize points

  paxes[0] = m * axes[0];

  paxes[1] = m * axes[1];

  paxes[2] = m * axes[2];

  paxes[0].de_homogenize();

  paxes[1].de_homogenize();

  paxes[2].de_homogenize();

  for (int i=0;i<9;i++) 

    {

      pp[i] = m * p[i];

      pp[i].de_homogenize();

    }

  //----------------------------------------

  // 5. Draw _projected_ points in 2D using OpenGL

  // Clear screen

  glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );

  glBegin(GL_LINES);

  glColor3f(1,0,0);

  glVertex2fv(pp[0].get());

  glVertex2fv(paxes[0].get());

  glColor3f(0,1,0);

  glVertex2fv(pp[0].get());

  glVertex2fv(paxes[1].get());

  glColor3f(0,0,1);

  glVertex2fv(pp[0].get());

  glVertex2fv(paxes[2].get());

  glColor3f(0,0,0);  

  for(int i=0;i<4;i++)

    {

      glVertex2fv(pp[2*i           + 0 ].get());

      glVertex2fv(pp[2*i           + 1 ].get());

    }

  for(int i=0;i<4;i++)

    {

      glVertex2fv(pp[(4*(i/2) + i%2) + 0 ].get());

      glVertex2fv(pp[(4*(i/2) + i%2) + 2 ].get());

    }

  for(int i=0;i<4;i++)

    { 

      glVertex2fv(pp[1*i           + 0 ].get());

      glVertex2fv(pp[1*i           + 4 ].get());

    }

  glEnd();

	glFlush();

}

static void reshape( int width, int height )

{

  glViewport( 0, 0, width, height );

}

static void key( unsigned char key, int x, int y )

{

  switch (key) {

  case 27:

    exit(0);

    break;

  }

}

static void init_GL()

{

  // Initialize GL, i.e. setup projection

  // and possibly other things as well

  glClearColor(1,1,1,1);

  gluOrtho2D(-3,3,-3,3);    

}

// static void idle()

// {

//   glutPostRedisplay();

// }

static void init_GLUT(int argc, char *argv[])

{

  // Initialize glut, open and create window.

  glutInit( &argc, argv );

  glutInitWindowSize( 400 , 400 );

  glutCreateWindow(argv[0]);

  // Register callback functions

  glutReshapeFunc( reshape );

  glutKeyboardFunc( key );

  glutDisplayFunc( display );

  // glutIdleFunc( idle );

}

int main( int argc, char *argv[] )

{

  init_GLUT(argc, argv);

  init_GL();

  glutMainLoop();

  return 0;

}