#include "BoxDrawArray.h"

#include <math.h>

using namespace std;

namespace X3DTK {
namespace GL {

int BoxDrawArray::_count = 0;
BoxDrawArray *BoxDrawArray::_ref = 0;

BoxDrawArray *BoxDrawArray::getInstance()
{
  if (_count == 0)
    _ref = new BoxDrawArray();
  ++_count;
    
  return _ref;  
}

void BoxDrawArray::removeInstance()
{
  if (_count > 0)
  {
    --_count;
    if (_count == 0)
      delete _ref;
  }    
}

BoxDrawArray::BoxDrawArray()
{
  //size the array
  _boxVertexArray = vector<N3F_V3F>(24);
  _boxIndexArray = vector<unsigned int>(36);
    
  //computing the vertex array
  //front face 
  _boxVertexArray[0].normal = SFVec3f(0.0f, 0.0f, 1.0f);
  _boxVertexArray[0].vertex = SFVec3f(-0.5f, -0.5f, 0.5f);
  _boxVertexArray[1].normal = SFVec3f(0.0f, 0.0f, 1.0f);
  _boxVertexArray[1].vertex = SFVec3f(-0.5f, 0.5f, 0.5f);
  _boxVertexArray[2].normal = SFVec3f(0.0f, 0.0f, 1.0f);
  _boxVertexArray[2].vertex = SFVec3f(0.5f, 0.5f, 0.5f);
  _boxVertexArray[3].normal = SFVec3f(0.0f, 0.0f, 1.0f);
  _boxVertexArray[3].vertex = SFVec3f(0.5f, -0.5f, 0.5f);  
  
  //back face 
  _boxVertexArray[4].normal = SFVec3f(0.0f, 0.0f, -1.0f);
  _boxVertexArray[4].vertex = SFVec3f(0.5f, -0.5f, -0.5f);
  _boxVertexArray[5].normal = SFVec3f(0.0f, 0.0f, -1.0f);
  _boxVertexArray[5].vertex = SFVec3f(0.5f, 0.5f, -0.5f);
  _boxVertexArray[6].normal = SFVec3f(0.0f, 0.0f, -1.0f);
  _boxVertexArray[6].vertex = SFVec3f(-0.5f, 0.5f, -0.5f);
  _boxVertexArray[7].normal = SFVec3f(0.0f, 0.0f, -1.0f);
  _boxVertexArray[7].vertex = SFVec3f(-0.5f, -0.5f, -0.5f);  
  
  //left face 
  _boxVertexArray[8].normal = SFVec3f(-1.0f, 0.0f, 0.0f);
  _boxVertexArray[8].vertex = SFVec3f(-0.5f, -0.5f, -0.5f);
  _boxVertexArray[9].normal = SFVec3f(-1.0f, 0.0f, 0.0f);
  _boxVertexArray[9].vertex = SFVec3f(-0.5f, 0.5f, -0.5f);
  _boxVertexArray[10].normal = SFVec3f(-1.0f, 0.0f, 0.0f);
  _boxVertexArray[10].vertex = SFVec3f(-0.5f, 0.5f, 0.5f);
  _boxVertexArray[11].normal = SFVec3f(-1.0f, 0.0f, 0.0f);
  _boxVertexArray[11].vertex = SFVec3f(-0.5f, -0.5f, 0.5f);  
  
  //right face 
  _boxVertexArray[12].normal = SFVec3f(1.0f, 0.0f, 0.0f);
  _boxVertexArray[12].vertex = SFVec3f(0.5f, -0.5f, 0.5f);
  _boxVertexArray[13].normal = SFVec3f(1.0f, 0.0f, 0.0f);
  _boxVertexArray[13].vertex = SFVec3f(0.5f, 0.5f, 0.5f);
  _boxVertexArray[14].normal = SFVec3f(1.0f, 0.0f, 0.0f);
  _boxVertexArray[14].vertex = SFVec3f(0.5f, 0.5f, -0.5f);
  _boxVertexArray[15].normal = SFVec3f(1.0f, 0.0f, 0.0f);
  _boxVertexArray[15].vertex = SFVec3f(0.5f, -0.5f, -0.5f);  
  
  //bottom face 
  _boxVertexArray[16].normal = SFVec3f(0.0f, -1.0f, 0.0f);
  _boxVertexArray[16].vertex = SFVec3f(-0.5f, -0.5f, -0.5f);
  _boxVertexArray[17].normal = SFVec3f(0.0f, -1.0f, 0.0f);
  _boxVertexArray[17].vertex = SFVec3f(-0.5f, -0.5f, 0.5f);
  _boxVertexArray[18].normal = SFVec3f(0.0f, -1.0f, 0.0f);
  _boxVertexArray[18].vertex = SFVec3f(0.5f, -0.5f, 0.5f);
  _boxVertexArray[19].normal = SFVec3f(0.0f, -1.0f, 0.0f);
  _boxVertexArray[19].vertex = SFVec3f(0.5f, -0.5f, -0.5f);  
  
  //top face 
  _boxVertexArray[20].normal = SFVec3f(0.0f, 1.0f, 0.0f);
  _boxVertexArray[20].vertex = SFVec3f(-0.5f, 0.5f, 0.5f);
  _boxVertexArray[21].normal = SFVec3f(0.0f, 1.0f, 0.0f);
  _boxVertexArray[21].vertex = SFVec3f(-0.5f, 0.5f, -0.5f);
  _boxVertexArray[22].normal = SFVec3f(0.0f, 1.0f, 0.0f);
  _boxVertexArray[22].vertex = SFVec3f(0.5f, 0.5f, -0.5f);
  _boxVertexArray[23].normal = SFVec3f(0.0f, 1.0f, 0.0f);
  _boxVertexArray[23].vertex = SFVec3f(0.5f, 0.5f, 0.5f);  
  
  //computing the index array
  for (unsigned short face = 0; face < 6; ++face)
  {
    _boxIndexArray[6*face + 0] = 4*face + 0;
    _boxIndexArray[6*face + 1] = 4*face + 1;
    _boxIndexArray[6*face + 2] = 4*face + 3;
    _boxIndexArray[6*face + 3] = 4*face + 3;
    _boxIndexArray[6*face + 4] = 4*face + 1;
    _boxIndexArray[6*face + 5] = 4*face + 2;
  }  
}  

unsigned int BoxDrawArray::getBoxSize() const
{
  return _boxIndexArray.size();
}

const void *BoxDrawArray::getBoxVertexArrayAddress() const
{
  return &_boxVertexArray.front();
}

const unsigned int *BoxDrawArray::getBoxIndexArrayAddress() const
{
  return &_boxIndexArray.front();
}

}
}