#include "Dots.h"
#include <cmath>
#include <climits>
#include "vgl.h"
#include <cstdlib>
#include <time.h>
#include <vector>

#include <iostream>
using namespace std;

Dots::Dots() {
  int i;

  display = true;

  return;
}

Dots::~Dots() {
   glDeleteBuffers(1, &bufferID);
   glDeleteVertexArrays(1, &VAONumber);
   return;
}

void Dots::CreatePoints(int num)  {

    int i;
    Vertex v;

    if (num < 3 or num > 300000) {
        num = 300;
    }

    for(i=0;i<num;i++) {
       v.position[0] = 1.0-2.0*(rand()/float(RAND_MAX));
       v.position[1] = 1.0-2.0*(rand()/float(RAND_MAX));
       v.color[0] = rand()/float(RAND_MAX);
       v.color[1] = rand()/float(RAND_MAX);
       v.color[2] = rand()/float(RAND_MAX);

       v.size = rand()/float(RAND_MAX);
       points.push_back(v);
    }
}

void Dots::BindDots(GLuint prog, int num) {

  GLint   attribLoc;

  CreatePoints(num);
   
  glGenVertexArrays(1, &VAONumber);

  glBindVertexArray(VAONumber);
  glGenBuffers(1,&bufferID);

  glBindBuffer(GL_ARRAY_BUFFER, bufferID);
  // warning changed code
  glBufferData(GL_ARRAY_BUFFER, points.size()*sizeof(Vertex),
        points.data(), GL_STATIC_DRAW);

 
  attribLoc = glGetAttribLocation(prog, "vPosition");
  // warning changed code here:
  glVertexAttribPointer(attribLoc, 2, GL_FLOAT, GL_FALSE, sizeof(Vertex),
                    BUFFER_OFFSET(offsetof(Vertex,position)));
  glEnableVertexAttribArray(attribLoc);

  // warning changed code here.
  attribLoc = glGetAttribLocation(prog, "vColor");
  glVertexAttribPointer(attribLoc, 3, GL_FLOAT, GL_FALSE, sizeof(Vertex)
                   , BUFFER_OFFSET(offsetof(Vertex, color)));
  glEnableVertexAttribArray(attribLoc); 

  attribLoc = glGetAttribLocation(prog, "vSize");
  glVertexAttribPointer(attribLoc, 1, GL_FLOAT, GL_FALSE, sizeof(Vertex)
                   , BUFFER_OFFSET(offsetof(Vertex, size)));
  glEnableVertexAttribArray(attribLoc); 

  // unbind the array
  glBindVertexArray(0);

  tsLoc = glGetUniformLocation(prog, "time");

  return;
}

void Dots::ToggleDisplay() {
   display = !display;
   return;
}

void Dots::Display() {

  static bool dir = true;

  if (dir) {
     timeStep += 0.01;
  } else {
     timeStep -= 0.01;
  }

  if (timeStep > 1) {
     dir = false;
  }
  if (timeStep < 0) {
     dir = true;
  }

  if (display) {
      glEnable(GL_PROGRAM_POINT_SIZE);
      glUniform1f(tsLoc, timeStep);

      glBindVertexArray(VAONumber);
      glDrawArrays(GL_POINTS, 0, points.size());
      glBindVertexArray(0);
      glDisable(GL_PROGRAM_POINT_SIZE);
  }

  return;
}