#include <TestFboSwap.h>
#include <poly/Log.h>

using namespace poly;

TestFboSwap::TestFboSwap()
  :dx(0)
{
  
  fbo[0] = 0;
  fbo[1] = 0;
  tex[0] = 0;
  tex[1] = 0;
}

TestFboSwap::~TestFboSwap() {
}

int TestFboSwap::init() {

  if (0 != fbo[0]) {
    SX_ERROR("Alredy initialized.");
    return -1;
  }

  if (0 != createFbo(fbo[0], tex[0])) {
    return -2;
  }

  if (0 != createFbo(fbo[1], tex[1])) {
    return -3;
  }
   
  return 0;
}

int TestFboSwap::createFbo(GLuint& fboOut, GLuint& texOut) {

  if (0 != fboOut) {
    SX_ERROR("Given FBO is not 0, already created?");
    return -1;
  }

  if (0 != texOut) {
    SX_ERROR("Given TEX is not 0, already created?");
    return -2;
  }

  glGenTextures(1, &texOut);
  glBindTexture(GL_TEXTURE_2D, texOut);
  glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 1024, 1024, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
  glBindTexture(GL_TEXTURE_2D, 0);

  glGenFramebuffers(1, &fboOut);
  glBindFramebuffer(GL_FRAMEBUFFER, fboOut);
  glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, texOut, 0);

  if (GL_FRAMEBUFFER_COMPLETE != glCheckFramebufferStatus(GL_FRAMEBUFFER)) {
    SX_ERROR("Framebuffer not yet complete.");
    glBindFramebuffer(GL_FRAMEBUFFER, 0);
    return -3;
  }

  glBindFramebuffer(GL_FRAMEBUFFER, 0);

  return 0;
}

void TestFboSwap::activate() {

  //  glWaitSync();
  glBindFramebuffer(GL_FRAMEBUFFER, fbo[dx]);
  glDrawBuffer(GL_COLOR_ATTACHMENT0);
  glViewport(0, 0, 1024, 1024);
}

void TestFboSwap::swap() {
  dx = 1 - dx;
}

GLuint TestFboSwap::getReadTexture() {
  return tex[dx - 1];
}