#include "Viewer.h"
#include <math.h>
#include <iostream>
#include <qfiledialog.h>
#include <qmessagebox.h> 

using namespace X3DTK;
using namespace std;

Viewer::Viewer()
{
}

Viewer::~Viewer()
{
  scene.release();
}

void Viewer::keyPressEvent(QKeyEvent *e)
{
  switch (e->key())
  {
    case Qt::Key_L : loadFile(); updateGL(); break;
    case Qt::Key_V : toggleDrawPoints(); updateGL(); break;
    case Qt::Key_E : toggleDrawEdges(); updateGL(); break;
    case Qt::Key_F : toggleDrawFaces(); updateGL(); break;
    case Qt::Key_C : toggleOneColorPerMesh(); updateGL(); break;
    default        : QGLViewer::keyPressEvent(e);
  }
}

void Viewer::loadFile()
{
  QString name = QFileDialog::getOpenFileName("", "X3D files (*.x3d *.X3D);;All files (*)", this);
  
  // In case of Cancel
  if (name.isEmpty())
    return;

  // Loads the file name.
  scene.load(name);

  // QGLViewer settings.
  setSceneBoundingBox(
    qglviewer::Vec(scene.getBBoxMin()[0],scene.getBBoxMin()[1],scene.getBBoxMin()[2]), 
    qglviewer::Vec(scene.getBBoxMax()[0],scene.getBBoxMax()[1],scene.getBBoxMax()[2])
  );
  setSceneRadius(2.0f*sceneRadius());
  showEntireScene(); 
}

void Viewer::init()
{
  glPolygonOffset(-2.0, -2.0);
#ifdef GL_RESCALE_NORMAL
  glEnable(GL_RESCALE_NORMAL);
#endif
  loadFile();
}

void Viewer::draw()
{
  scene.drawMesh();
  scene.drawSelected();
}

void Viewer::about()
{
  QMessageBox::about(this, "about the simpleAnimationViewer", "this is an example showing how to animate a simple X3D scene.Type 'h' to display help");
}

void Viewer::help() const
{
  QMessageBox *mb = new QMessageBox("help", helpString(), QMessageBox::NoIcon,QMessageBox::Ok | QMessageBox::Default, QMessageBox::NoButton,QMessageBox::NoButton, NULL, "Help", false,Qt::WStyle_DialogBorder | Qt::WType_Dialog | Qt::WDestructiveClose);
  mb->show();
}

void Viewer::select(const QMouseEvent* e)
{
  // Make openGL context current
  makeCurrent();
  
  const int SENSITIVITY = 6;
  const int NB_HITS_MAX = 32768;
  
  // Prepare the selection mode
  static GLuint hits[NB_HITS_MAX];
  
  glSelectBuffer(NB_HITS_MAX, hits);
  glRenderMode(GL_SELECT);
  glInitNames();

  // Loads the matrices
  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();
  GLint viewport[4];
  glGetIntegerv(GL_VIEWPORT,viewport);
  camera()->getViewport(viewport);
  gluPickMatrix(static_cast<GLdouble>(e->x()), static_cast<GLdouble>(e->y()), SENSITIVITY, SENSITIVITY, viewport);

  // Don't use loadProjectionMatrix() directly as it clears the GL_PROJECTION matrix with a glLoadIdentity.
  // The false flag indicates that no glLoadIdentity should be called, in order to combine the matrices.
  camera()->loadProjectionMatrix(false);
  camera()->loadModelViewMatrix();
  
  // Render scene with objects ids
  scene.drawMesh(true);
  
  glFlush();

  // Get the results
  GLint nb_hits = glRenderMode(GL_RENDER);

  // Too many elements in selection buffer
  if (nb_hits < 0)
    return;

  // No selection
  if (nb_hits == 0)
  {
    scene.setSelectedType(NOTHING);
    cout << "No selection" << endl;
    return;
  }
  
  // Interpret results
  unsigned int zMin = hits[1];
  scene.setSelectedMesh(hits[3]);
  scene.setSelectedType(static_cast<SelectedType>(hits[4]));
  scene.setSelectedId(hits[5]);
  
  for (int i=1; i<nb_hits; ++i)
    // Prefer vertices over edges and edges over faces
    if (hits[i*6+1] < zMin+(((int)scene.getSelectedType() - hits[i*6+4])*200000))
    {
      zMin = hits[i*6+1];
      scene.setSelectedMesh(hits[i*6+3]);
      scene.setSelectedType(static_cast<SelectedType>(hits[i*6+4]));
      scene.setSelectedId(hits[i*6+5]);
    }
  
  switch (scene.getSelectedType())
  {
    case NOTHING : break;
    case VERTICES :cout << "Vertex "; break;
    case EDGES :   cout << "Edge "; break;
    case FACES :   cout << "Face "; break;
  }
  cout << scene.getSelectedId() << " selected on mesh " << scene.getSelectedMesh() << endl;
}

QString Viewer::helpString() const
{
  QString message("<b>L</b> loads a new file<br>");
  message += "<b>F</b> toggles face display<br>";
  message += "<b>E</b> toggles edge display<br>";
  message += "<b>V</b> toggles vertex display<br>";
  message += "<b>C</b> toggles one color per mesh<br>";
  message += "<b>Shift+click</b> to select an element<br>";
  message += "<hr>";
  message += QGLViewer::helpString();
  return message;
}