#include <QtCore/qglobal.h>
#include <QFileDialog>
#include <QColorDialog>
#include <CGAL/Qt/manipulatedCameraFrame.h>
#include <CGAL/Qt/manipulatedFrame.h>
#include <CGAL/Three/Three.h>

#include <fstream>


#include "Messages_interface.h"
#include "Scene_points_with_normal_item.h"
#include "Item_classification_base.h"
#include "Point_set_item_classification.h"
#include "Cluster_classification.h"
#include "Scene_surface_mesh_item.h"
#include "Surface_mesh_item_classification.h"
#include "Scene_polylines_item.h"
#include "Scene_polygon_soup_item.h"

#include <CGAL/Three/Scene_interface.h>
#include <CGAL/Three/Polyhedron_demo_plugin_helper.h>
#include <CGAL/Three/Three.h>

#include <CGAL/Random.h>
#include <CGAL/Real_timer.h>

#include <QMultipleInputDialog.h>

#include "ui_Classification_widget.h"
#include "ui_Classification_advanced_widget.h"

#include <QAction>
#include <QMainWindow>
#include <QApplication>
#include <QCheckBox>
#include <QRadioButton>
#include <QInputDialog>
#include <QMessageBox>
#include <QSpinBox>
#include "CGAL_double_edit.h"
#include <QSlider>

#include <map>

#include <boost/graph/adjacency_list.hpp>
#include <CGAL/boost/graph/split_graph_into_polylines.h>

using namespace CGAL::Three;

class Polyhedron_demo_classification_plugin :
  public QObject,
  public Polyhedron_demo_plugin_helper
{
  Q_OBJECT
    Q_INTERFACES(CGAL::Three::Polyhedron_demo_plugin_interface)
    Q_PLUGIN_METADATA(IID "com.geometryfactory.PolyhedronDemo.PluginInterface/1.0")

  struct LabelButton
  {
    QPushButton* color_button;
    QMenu* menu;
    char shortcut;

    QColor color;

    QLabel* label2;
    QComboBox* effect;

    LabelButton (QWidget* parent,
                 const char* name,
                 const QColor& color,
                 const char shortcut)
      : shortcut (shortcut), color (color)
    {
      color_button = new QPushButton (tr("%1 (%2)").arg(name).arg((char)(std::toupper(shortcut))), parent);

      menu = new QMenu("Label Menu", color_button);

      QColor text_color (255, 255, 255);
      if (color.red() * 0.299 + color.green() * 0.587 + color.blue() * 0.114 > 128)
        text_color = QColor (0, 0, 0);

      QString s("QPushButton { font-weight: bold; background: #"
                + QString(color.red() < 16? "0" : "") + QString::number(color.red(),16)
                + QString(color.green() < 16? "0" : "") + QString::number(color.green(),16)
                + QString(color.blue() < 16? "0" : "") + QString::number(color.blue(),16)
                + "; color: #"
                + QString(text_color.red() < 16? "0" : "") + QString::number(text_color.red(),16)
                + QString(text_color.green() < 16? "0" : "") + QString::number(text_color.green(),16)
                + QString(text_color.blue() < 16? "0" : "") + QString::number(text_color.blue(),16)
                + "; }");

      color_button->setStyleSheet(s);
      color_button->setMenu(menu);


      label2 = new QLabel (name, parent);
      effect = new QComboBox;
      effect->addItem("Penalized");
      effect->addItem("Neutral");
      effect->addItem("Favored");
    }
    ~LabelButton ()
    {
    }
    void change_color (const QColor& color)
    {
      this->color = color;
      QColor text_color (255, 255, 255);
      if (color.red() * 0.299 + color.green() * 0.587 + color.blue() * 0.114 > 128)
        text_color = QColor (0, 0, 0);
      QString s("QPushButton { font-weight: bold; background: #"
                + QString(color.red() < 16? "0" : "") + QString::number(color.red(),16)
                + QString(color.green() < 16? "0" : "") + QString::number(color.green(),16)
                + QString(color.blue() < 16? "0" : "") + QString::number(color.blue(),16)
                + "; color: #"
                + QString(text_color.red() < 16? "0" : "") + QString::number(text_color.red(),16)
                + QString(text_color.green() < 16? "0" : "") + QString::number(text_color.green(),16)
                + QString(text_color.blue() < 16? "0" : "") + QString::number(text_color.blue(),16)
                + "; }");

      color_button->setStyleSheet(s);
      color_button->update();
    }

  };


public:
  bool applicable(QAction*) const {
      return
        qobject_cast<Scene_points_with_normal_item*>(scene->item(scene->mainSelectionIndex()))
        || qobject_cast<Scene_surface_mesh_item*>(scene->item(scene->mainSelectionIndex()));
  }
  void print_message(QString message) { CGAL::Three::Three::information(message); }
  QList<QAction*> actions() const { return QList<QAction*>() << actionClassification; }

  using Polyhedron_demo_plugin_helper::init;
  void init(QMainWindow* mainWindow, CGAL::Three::Scene_interface* scene_interface, Messages_interface* m) {

    mw = mainWindow;
    scene = scene_interface;
    messages = m;
    actionClassification = new QAction(tr("Classification"), mw);
    connect(actionClassification, SIGNAL(triggered()), this, SLOT(classification_action()));

    dock_widget = new QDockWidget("Classification", mw);
    dock_widget->setVisible(false);
    dock_widget_adv = new QDockWidget("Classification (Advanced)", mw);
    dock_widget_adv->setVisible(false);

    label_button = new QPushButton(QIcon(QString(":/cgal/icons/plus")), "", dock_widget);

    QMenu* label_menu = new QMenu("Label Menu", label_button);
    label_button->setMenu (label_menu);

    QAction* add_new_label = label_menu->addAction ("Add new label(s)");
    connect(add_new_label,  SIGNAL(triggered()), this,
            SLOT(on_add_new_label_clicked()));

    label_menu->addSeparator();

    QAction* use_config_building = label_menu->addAction ("Use configuration ground/vegetation/building");
    connect(use_config_building,  SIGNAL(triggered()), this,
            SLOT(on_use_config_building_clicked()));
    QAction* use_config_roof = label_menu->addAction ("Use configuration ground/vegetation/roof/facade");
    connect(use_config_roof,  SIGNAL(triggered()), this,
            SLOT(on_use_config_roof_clicked()));
    QAction* use_config_las = label_menu->addAction ("Use LAS standard configuration");
    connect(use_config_las,  SIGNAL(triggered()), this,
            SLOT(on_use_las_config_clicked()));

    label_menu->addSeparator();


    QAction* generate = label_menu->addAction ("Create one point set item per label");
    connect(generate,  SIGNAL(triggered()), this,
            SLOT(on_generate_items_button_clicked()));

    label_menu->addSeparator();

    QAction* clear_labels = label_menu->addAction ("Clear labels");
    connect(clear_labels,  SIGNAL(triggered()), this,
            SLOT(on_clear_labels_clicked()));

    ui_widget.setupUi(dock_widget);
    ui_widget_adv.setupUi(dock_widget_adv);
    addDockWidget(dock_widget);
    addDockWidget(dock_widget_adv);

    color_att = QColor (75, 75, 77);

    QAction* compute_features = ui_widget.features_menu->addAction ("Compute features...");
    connect(compute_features,  SIGNAL(triggered()), this,
            SLOT(on_compute_features_button_clicked()));

    action_statistics = ui_widget.features_menu->addAction ("Show feature statistics");
    connect(action_statistics,  SIGNAL(triggered()), this,
            SLOT(on_statistics_clicked()));

    action_reset_local = ui_widget.training_menu->addAction ("Reset training set of selection");
    connect(action_reset_local,  SIGNAL(triggered()), this,
            SLOT(on_reset_training_set_of_selection_clicked()));

    action_reset = ui_widget.training_menu->addAction ("Reset all training sets");
    connect(action_reset,  SIGNAL(triggered()), this,
            SLOT(on_reset_training_sets_clicked()));

    action_random_region = ui_widget.training_menu->addAction ("Select random region");
    action_random_region->setShortcut(Qt::SHIFT | Qt::Key_S);
    connect(action_random_region,  SIGNAL(triggered()), this,
            SLOT(on_select_random_region_clicked()));

    action_validate = ui_widget.training_menu->addAction ("Validate labels of current selection as training sets");
    connect(action_validate,  SIGNAL(triggered()), this,
            SLOT(on_validate_selection_clicked()));

    classifier = ui_widget.classifier_menu->addSection (CGAL_CLASSIFICATION_ETHZ_ID);

    action_train = ui_widget.classifier_menu->addAction ("Train...");
    action_train->setShortcut(Qt::SHIFT | Qt::Key_T);
    connect(action_train,  SIGNAL(triggered()), this,
            SLOT(on_train_clicked()));

    ui_widget.classifier_menu->addSeparator();

    action_run = ui_widget.classifier_menu->addAction ("Classify");
    connect(action_run,  SIGNAL(triggered()), this,
            SLOT(on_run_button_clicked()));

    action_run_smoothed = ui_widget.classifier_menu->addAction ("Classify with local smoothing...");
    connect(action_run_smoothed,  SIGNAL(triggered()), this,
            SLOT(on_run_smoothed_button_clicked()));

    action_run_graphcut = ui_widget.classifier_menu->addAction ("Classify with Graph Cut...");
    connect(action_run_graphcut,  SIGNAL(triggered()), this,
            SLOT(on_run_graphcut_button_clicked()));

    ui_widget.classifier_menu->addSeparator();

    action_save_config = ui_widget.classifier_menu->addAction ("Save current configuration...");
    action_load_config = ui_widget.classifier_menu->addAction ("Load configuration...");
    connect(action_save_config,  SIGNAL(triggered()), this,
            SLOT(on_save_config_button_clicked()));
    connect(action_load_config,  SIGNAL(triggered()), this,
            SLOT(on_load_config_button_clicked()));

    ui_widget.classifier_menu->addSeparator();

    QAction* switch_classifier = ui_widget.classifier_menu->addAction ("Switch to another classifier...");
    connect(switch_classifier,  SIGNAL(triggered()), this,
            SLOT(on_switch_classifier_clicked()));

    connect(ui_widget.display,  SIGNAL(currentIndexChanged(int)), this,
            SLOT(on_display_button_clicked(int)));

    connect(ui_widget.minDisplay,  SIGNAL(released()), this,
            SLOT(on_min_display_button_clicked()));
    connect(ui_widget.maxDisplay,  SIGNAL(released()), this,
            SLOT(on_max_display_button_clicked()));

    connect(ui_widget_adv.selected_feature,  SIGNAL(currentIndexChanged(int)), this,
            SLOT(on_selected_feature_changed(int)));
    connect(ui_widget_adv.feature_weight,  SIGNAL(valueChanged(int)), this,
            SLOT(on_feature_weight_changed(int)));

    connect(ui_widget.help,  SIGNAL(clicked()), this,
            SLOT(on_help_clicked()));
    connect(ui_widget.close,  SIGNAL(clicked()), this,
            SLOT(ask_for_closing()));

    QObject* scene_obj = dynamic_cast<QObject*>(scene_interface);
    if(scene_obj)
    {
      connect(scene_obj, SIGNAL(itemAboutToBeDestroyed(CGAL::Three::Scene_item*)), this,
              SLOT(item_about_to_be_destroyed(CGAL::Three::Scene_item*)));

      connect(scene_obj, SIGNAL(itemIndexSelected(int)), this,
              SLOT(update_plugin(int)));
    }
  }
  virtual void closure()
  {
    dock_widget->hide();
    close_classification();
  }


public Q_SLOTS:

  void item_about_to_be_destroyed(CGAL::Three::Scene_item* scene_item) {
    Item_map::iterator it = item_map.find(scene_item);
    if (it != item_map.end())
      {
        Item_classification_base* classif = it->second;
        item_map.erase(it); // first erase from map, because scene->erase will cause a call to this function
        delete classif;
      }
  }

  void classification_action()
  {
    dock_widget->show();
    dock_widget->raise();
    if (Scene_points_with_normal_item* points_item
             = qobject_cast<Scene_points_with_normal_item*>(scene->item(scene->mainSelectionIndex())))
    {
      create_from_item(points_item);
      QAction* ps_selection = mw->findChild<QAction*>("actionPointSetSelection");
      if (ps_selection)
        ps_selection->trigger();
      else
        print_message("Warning: can't find Point Set Selection plugin");
    }
    else if (Scene_surface_mesh_item* mesh_item
             = qobject_cast<Scene_surface_mesh_item*>(scene->item(scene->mainSelectionIndex())))
    {
      create_from_item(mesh_item);
      QAction* sm_selection = mw->findChild<QAction*>("actionSelection");
      if (sm_selection)
        sm_selection->trigger();
      else
        print_message("Warning: can't find Surface Mesh Selection plugin");
    }

    on_help_clicked();
  }


  void ask_for_closing()
  {
    QMessageBox oknotok;
    oknotok.setWindowTitle("Closing classification");
    oknotok.setText("All computed data structures will be discarded.\nColored display will be reinitialized.\nLabels and training information will remain in the classified items.\n\nAre you sure you want to close?");
    oknotok.setStandardButtons(QMessageBox::Yes);
    oknotok.addButton(QMessageBox::No);
    oknotok.setDefaultButton(QMessageBox::Yes);

    if (oknotok.exec() == QMessageBox::Yes)
      close_classification();
  }

  void close_classification()
  {
    for (Item_map::iterator it = item_map.begin(); it != item_map.end(); ++ it)
      {
        Item_classification_base* classif = it->second;
        item_changed (classif->item());
        delete classif;
      }
    item_map.clear();
    dock_widget->hide();
  }

  void item_changed (Scene_item* item)
  {
    scene->itemChanged(item);
    item->invalidateOpenGLBuffers();
  }

  void update_plugin(int i)
  {
    if (dock_widget->isVisible())
      update_plugin_from_item(get_classification(scene->item(i)));
  }

  void disable_everything ()
  {
    ui_widget.features_menu->setEnabled(false);
    ui_widget.training_menu->setEnabled(false);
    ui_widget.classifier_menu->setEnabled(false);
    ui_widget.view->setEnabled(false);
    ui_widget.frame->setEnabled(false);
  }

  void enable_computation()
  {
    ui_widget.features_menu->setEnabled(true);
    ui_widget.training_menu->setEnabled(true);
    ui_widget.classifier_menu->setEnabled(false);
    action_statistics->setEnabled(false);
    action_train->setEnabled(false);
    action_reset_local->setEnabled(true);
    action_reset->setEnabled(true);
    action_random_region->setEnabled(true);
    action_validate->setEnabled(true);
    action_save_config->setEnabled(false);
    action_load_config->setEnabled(false);
    action_run->setEnabled(false);
    action_run_smoothed->setEnabled(false);
    action_run_graphcut->setEnabled(false);
    ui_widget.view->setEnabled(true);
    ui_widget.frame->setEnabled(true);
  }

  void enable_classif()
  {
    ui_widget.features_menu->setEnabled(true);
    ui_widget.training_menu->setEnabled(true);
    ui_widget.classifier_menu->setEnabled(true);
    action_statistics->setEnabled(true);
    action_train->setEnabled(true);
    action_reset_local->setEnabled(true);
    action_reset->setEnabled(true);
    action_random_region->setEnabled(true);
    action_validate->setEnabled(true);
    action_save_config->setEnabled(true);
    action_load_config->setEnabled(true);
    action_run->setEnabled(true);
    action_run_smoothed->setEnabled(true);
    action_run_graphcut->setEnabled(true);
    ui_widget.frame->setEnabled(true);
  }

  void update_plugin_from_item(Item_classification_base* classif)
  {
    disable_everything();
    if (classif != nullptr)
      {
        enable_computation();

        // Clear class labels
        for (std::size_t i = 0; i < label_buttons.size(); ++ i)
          {
            ui_widget.labelGrid->removeWidget (label_buttons[i].color_button);
            label_buttons[i].color_button->deleteLater();
            label_buttons[i].menu->deleteLater();
            ui_widget_adv.gridLayout->removeWidget (label_buttons[i].label2);
            delete label_buttons[i].label2;
            ui_widget_adv.gridLayout->removeWidget (label_buttons[i].effect);
            delete label_buttons[i].effect;
          }
        label_buttons.clear();

        // Add labels
        for (std::size_t i = 0; i < classif->number_of_labels(); ++ i)
          add_new_label (LabelButton (dock_widget,
                                      classif->label(i)->name().c_str(),
                                      classif->label_color(i),
                                      get_shortcut (i, classif->label(i)->name().c_str())));
        add_label_button();

        // Enabled classif if features computed
        if (classif->features_computed())
          enable_classif();

        int index = ui_widget.display->currentIndex();
        ui_widget.display->clear();
        ui_widget.display->addItem("Real colors");
        ui_widget.display->addItem("Classification");
        ui_widget.display->addItem("Training sets");
        ui_widget_adv.selected_feature->clear();
        classif->fill_display_combo_box(ui_widget.display, ui_widget_adv.selected_feature);
        if (index >= ui_widget.display->count())
        {
          ui_widget.display->setCurrentIndex(1);
          change_color (classif, 1);
        }
        else
        {
          ui_widget.display->setCurrentIndex(index);
          change_color (classif, index);
        }
        ui_widget_adv.selected_feature->setCurrentIndex(0);
      }
  }

  Item_classification_base* get_classification(Scene_item* item = nullptr)
  {
    if (!item)
      item = scene->item(scene->mainSelectionIndex());

    if (!item)
      return nullptr;

    Scene_polyhedron_selection_item* selection_item
      = qobject_cast<Scene_polyhedron_selection_item*>(item);
    if (selection_item)
      item = selection_item->polyhedron_item();

    Item_map::iterator it = item_map.find(item);

    if (it != item_map.end())
    {
      if (selection_item)
        dynamic_cast<Surface_mesh_item_classification*>(it->second)->set_selection_item(selection_item);
      return it->second;
    }

    return nullptr;
  }


  Item_classification_base* create_from_item(Scene_points_with_normal_item* points_item)
  {
    if (item_map.find(points_item) != item_map.end())
      return item_map[points_item];

    bool use_clusters = false;

    if (points_item->point_set()->has_property_map<int> ("shape"))
    {
      QMessageBox::StandardButton reply
        = QMessageBox::question(nullptr, "Point Set Classification",
                                "This point set is divided in clusters. Do you want to classify clusters instead of points?",
                                QMessageBox::Yes|QMessageBox::No, QMessageBox::Yes);

      use_clusters = (reply == QMessageBox::Yes);
    }

    QApplication::setOverrideCursor(Qt::WaitCursor);

    Item_classification_base* classif;
    if (use_clusters)
      classif = new Cluster_classification (points_item);
    else
      classif = new Point_set_item_classification (points_item);

    item_map.insert (std::make_pair (points_item, classif));

    QApplication::restoreOverrideCursor();
    update_plugin_from_item(classif);
    return classif;
  }

  Item_classification_base* create_from_item(Scene_surface_mesh_item* mesh_item)
  {
    if (item_map.find(mesh_item) != item_map.end())
      return item_map[mesh_item];

    QApplication::setOverrideCursor(Qt::WaitCursor);
    Item_classification_base* classif
      = new Surface_mesh_item_classification (mesh_item);
    item_map.insert (std::make_pair (mesh_item, classif));
    QApplication::restoreOverrideCursor();
    update_plugin_from_item(classif);
    return classif;
  }

  int get_classifier ()
  {
    if (classifier->text() == QString(CGAL_CLASSIFICATION_ETHZ_ID))
      return CGAL_CLASSIFICATION_ETHZ_NUMBER;
    if (classifier->text() == QString(CGAL_CLASSIFICATION_OPENCV_ID))
      return CGAL_CLASSIFICATION_OPENCV_NUMBER;
    if (classifier->text() == QString(CGAL_CLASSIFICATION_SOWF_ID))
      return CGAL_CLASSIFICATION_SOWF_NUMBER;

    std::cerr << "Error: unknown classifier" << std::endl;
    return -1;
  }

  void run (Item_classification_base* classif, int method,
            std::size_t subdivisions = 1,
            double smoothing = 0.5)
  {
    classif->run (method, get_classifier(), subdivisions, smoothing);
  }

  void on_help_clicked()
  {
    QMessageBox::information(dock_widget, QString("Classification"),
                             QString("Classification\n"
                                     "\n"
                                     "Welcome to CGAL Classification! Please read carefully this notice\n"
                                     "before using the plugin.\n"
                                     "\n"
                                     "[QUICK INTRODUCTION]\n"
                                     "\n"
                                     "In order to classify, you need to perform the following steps:\n"
                                     "\n"
                                     "1. Compute the features\n"
                                     "2. Set up the labels (ground, vegetation, etc.) that you need\n"
                                     "3. Select a training set for each of these labels\n"
                                     "4. Train the classifier\n"
                                     "\n"
                                     "You can then either select more inliers for training and train again\n"
                                     "to improve the results, classify with or without regularization or\n"
                                     "save the classifier's configuration.\n"
                                     "\n"
                                     "When loading a classifier's configuration, the computed features\n"
                                     "should be the same (same number of scales, etc.) and the labels should\n"
                                     "be the same as when the classifier's configuration was saved.\n"
                                     "\n"
                                     "For more information, please refer to the CGAL manual.\n"
                                     "\n"
                                     "[IMPORTANT NOTICE ON SAVING CLASSIFIED ITEMS]\n"
                                     "\n"
                                     "If you intend to save the file after classifying, PLEASE CLOSE THE\n"
                                     "CLASSIFICATION PLUGIN FIRST: for visualization, colors are saved in\n"
                                     "the point set. If you do not close the classification plugin, colors\n"
                                     "will be saved and might overwrite existing colors of the point cloud.\n"
                                     "\n"
                                     "Classification results will be saved if you use the PLY or LAS\n"
                                     "formats. Training will be saved if you use the PLY format.\n"));

  }

  void on_compute_features_button_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }

    QMultipleInputDialog dialog ("Compute Features", mw);
    QSpinBox* scales = dialog.add<QSpinBox> ("Number of scales:");
    scales->setRange (1, 99);
    scales->setValue (5);

    DoubleEdit* voxel_size = dialog.add<DoubleEdit> ("Voxel size (0 for automatic):");

    if (dialog.exec() != QDialog::Accepted)
      return;

    QApplication::setOverrideCursor(Qt::WaitCursor);

    float vsize = float(voxel_size->value());
    if (vsize == 0.f)
      vsize = -1.f; // auto value

    classif->compute_features (std::size_t(scales->value()), vsize);

    update_plugin_from_item(classif);
    QApplication::restoreOverrideCursor();
    item_changed(classif->item());
  }

  void on_save_config_button_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }

    QString filename;

    int classifier = get_classifier();
    if (classifier == CGAL_CLASSIFICATION_SOWF_NUMBER) // Sum of Weighted Featuers
      filename = QFileDialog::getSaveFileName(mw,
                                              tr("Save classification configuration"),
                                              tr("%1 (CGAL classif config).xml").arg(classif->item()->name()),
                                              "CGAL classification configuration (*.xml);;");
    else if (classifier == CGAL_CLASSIFICATION_ETHZ_NUMBER) // Random Forest (ETHZ)
      filename = QFileDialog::getSaveFileName(mw,
                                              tr("Save classification configuration"),
                                              tr("%1 (ETHZ random forest config).bin").arg(classif->item()->name()),
                                              "ETHZ random forest configuration (*.bin);;");
#ifdef CGAL_LINKED_WITH_OPENCV
    else if (classifier == CGAL_CLASSIFICATION_OPENCV_NUMBER) // Random Forest (OpenCV)
      filename = QFileDialog::getSaveFileName(mw,
                                              tr("Save classification configuration"),
                                              tr("%1 (OpenCV %2.%3 random forest config).xml")
                                              .arg(classif->item()->name())
                                              .arg(CV_MAJOR_VERSION)
                                              .arg(CV_MINOR_VERSION),
                                              tr("OpenCV %2.%3 random forest configuration (*.xml);;")
                                              .arg(CV_MAJOR_VERSION)
                                              .arg(CV_MINOR_VERSION));
#endif

    if (filename == QString())
      return;


    QApplication::setOverrideCursor(Qt::WaitCursor);

    classif->save_config (filename.toStdString().c_str(), classifier);

    QApplication::restoreOverrideCursor();

  }

  void on_load_config_button_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }
    QString filename;

    int classifier = get_classifier();
    if (classifier == CGAL_CLASSIFICATION_SOWF_NUMBER) // Sum of Weighted Featuers
      filename = QFileDialog::getOpenFileName(mw,
                                              tr("Open CGAL classification configuration"),
                                              ".",
                                              "CGAL classification configuration (*.xml);;All Files (*)");
    else if (classifier == CGAL_CLASSIFICATION_ETHZ_NUMBER) // Random Forest (ETHZ)
      filename = QFileDialog::getOpenFileName(mw,
                                              tr("Open ETHZ random forest configuration"),
                                              ".",
#if defined(CGAL_LINKED_WITH_BOOST_IOSTREAMS) && defined(CGAL_LINKED_WITH_BOOST_SERIALIZATION)
                                              "ETHZ random forest configuration (*.bin);Deprecated compressed ETHZ random forest configuration (*.gz);All Files (*)");
#else
                                              "ETHZ random forest configuration (*.bin);All Files (*)");
#endif

#ifdef CGAL_LINKED_WITH_OPENCV
    else if (classifier == CGAL_CLASSIFICATION_OPENCV_NUMBER) // Random Forest (OpenCV)
      filename = QFileDialog::getOpenFileName(mw,
                                              tr("Open OpenCV %2.%3 random forest configuration")
                                              .arg(CV_MAJOR_VERSION)
                                              .arg(CV_MINOR_VERSION),
                                              ".",
                                              tr("OpenCV %2.%3 random forest configuration (*.xml);;All Files (*)")
                                              .arg(CV_MAJOR_VERSION)
                                              .arg(CV_MINOR_VERSION));
#endif

    if (filename == QString())
      return;

    QApplication::setOverrideCursor(Qt::WaitCursor);

    classif->load_config (filename.toStdString().c_str(), classifier);
    update_plugin_from_item(classif);
    run (classif, 0);
    QApplication::restoreOverrideCursor();
    item_changed(classif->item());
  }

  void change_color (Item_classification_base* classif, int index)
  {
    float vmin = std::numeric_limits<float>::infinity();
    float vmax = std::numeric_limits<float>::infinity();

    classif->change_color (index, &vmin, &vmax);

    if (vmin == std::numeric_limits<float>::infinity() || vmax == std::numeric_limits<float>::infinity())
    {
      ui_widget.minDisplay->setEnabled(false);
      ui_widget.minDisplay->setText("Min");
      ui_widget.maxDisplay->setEnabled(false);
      ui_widget.maxDisplay->setText("Max");
    }
    else
    {
      ui_widget.minDisplay->setEnabled(true);
      ui_widget.minDisplay->setText(tr("Min (%1)").arg(vmin));
      ui_widget.maxDisplay->setEnabled(true);
      ui_widget.maxDisplay->setText(tr("Max (%1)").arg(vmax));
    }

    item_changed(classif->item());
  }


  void on_display_button_clicked(int index)
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      return;

    change_color (classif, index);
  }

  float display_button_value (QPushButton* button)
  {
    std::string text = button->text().toStdString();

    std::size_t pos1 = text.find('(');
    if (pos1 == std::string::npos)
      return std::numeric_limits<float>::infinity();
    std::size_t pos2 = text.find(')');
    if (pos2 == std::string::npos)
      return std::numeric_limits<float>::infinity();

    std::string fstring (text.begin() + pos1 + 1,
                         text.begin() + pos2);

    return float (std::atof(fstring.c_str()));
  }

  void on_min_display_button_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      return;

    float vmin = display_button_value (ui_widget.minDisplay);
    float vmax = display_button_value (ui_widget.maxDisplay);

    if (vmin == std::numeric_limits<float>::infinity()
        || vmax ==  std::numeric_limits<float>::infinity())
      return;

    bool ok = false;
    vmin = float(QInputDialog::getDouble((QWidget*)mw,
                                         tr("Set display ramp minimum value (saturate under):"),
                                         tr("Minimum value (pale blue):"),
                                         double(vmin),
                                         -10000000.0,
                                         double(vmax), 5, &ok));
    if (!ok)
      return;

    int index = ui_widget.display->currentIndex();

    classif->change_color (index, &vmin, &vmax);
    ui_widget.minDisplay->setText(tr("Min* (%1)").arg(vmin));

    item_changed(classif->item());
  }

  void on_max_display_button_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      return;

    float vmin = display_button_value (ui_widget.minDisplay);
    float vmax = display_button_value (ui_widget.maxDisplay);

    if (vmin == std::numeric_limits<float>::infinity()
        || vmax ==  std::numeric_limits<float>::infinity())
      return;

    bool ok = false;
    vmax = float(QInputDialog::getDouble((QWidget*)mw,
                                         tr("Set display ramp maximum value (saturate over):"),
                                         tr("Maximum value (dark red):"),
                                         double(vmax),
                                         double(vmin),
                                         10000000.0, 5, &ok));
    if (!ok)
      return;

    int index = ui_widget.display->currentIndex();

    classif->change_color (index, &vmin, &vmax);
    ui_widget.maxDisplay->setText(tr("Max* (%1)").arg(vmax));

    item_changed(classif->item());
  }

  void on_run_button_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }
    QApplication::setOverrideCursor(Qt::WaitCursor);
    CGAL::Real_timer t;
    t.start();
    run (classif, 0);
    t.stop();
    std::cerr << "Raw classification computed in " << t.time() << " second(s)" << std::endl;
    QApplication::restoreOverrideCursor();
    item_changed(classif->item());
  }

  void on_run_smoothed_button_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }

    QApplication::setOverrideCursor(Qt::WaitCursor);
    CGAL::Real_timer t;
    t.start();
    run (classif, 1);
    t.stop();
    std::cerr << "Smoothed classification computed in " << t.time() << " second(s)" << std::endl;
    QApplication::restoreOverrideCursor();
    item_changed(classif->item());
  }

  void on_run_graphcut_button_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }

    QMultipleInputDialog dialog ("Classify with Graph Cut", mw);
    QSpinBox* subdivisions = dialog.add<QSpinBox> ("Number of subdivisons: ");
    subdivisions->setRange (1, 9999);
    subdivisions->setValue (16);

    DoubleEdit* smoothing = dialog.add<DoubleEdit> ("Regularization weight: ");

    smoothing->setText(tr("%1").arg(0.5));

    if (dialog.exec() != QDialog::Accepted)
      return;

    QApplication::setOverrideCursor(Qt::WaitCursor);
    CGAL::Real_timer t;
    t.start();
    run (classif, 2, std::size_t(subdivisions->value()), smoothing->value());
    t.stop();
    std::cerr << "Graph Cut classification computed in " << t.time() << " second(s)" << std::endl;
    QApplication::restoreOverrideCursor();
    item_changed(classif->item());
  }

  void on_create_point_set_item()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }

    QPushButton* label_clicked = qobject_cast<QPushButton*>(QObject::sender()->parent()->parent());

    if (label_clicked == nullptr)
      std::cerr << "Error" << std::endl;
    else
    {
      int index = ui_widget.labelGrid->indexOf(label_clicked);
      int row_index, column_index, row_span, column_span;
      ui_widget.labelGrid->getItemPosition(index, &row_index, &column_index, &row_span, &column_span);

      int position = row_index * 3 + column_index;

      Scene_item* item =  classif->generate_one_item
        (classif->item()->name().toStdString().c_str(), position);

      Scene_points_with_normal_item* points_item
        = qobject_cast<Scene_points_with_normal_item*>(item);

      if (!points_item)
        return;

      if (points_item->point_set()->empty())
        delete points_item;
      else
        scene->addItem (points_item);
    }
  }

  void on_generate_items_button_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }


    QApplication::setOverrideCursor(Qt::WaitCursor);

    std::vector<Scene_item*> new_items;
    classif->generate_one_item_per_label
      (new_items, classif->item()->name().toStdString().c_str());

    for (std::size_t i = 0; i < new_items.size(); ++ i)
      {
        Scene_points_with_normal_item* points_item
          = qobject_cast<Scene_points_with_normal_item*>(new_items[i]);
        if (!points_item)
          continue;

        if (points_item->point_set()->empty())
          delete points_item;
        else
          scene->addItem (points_item);
      }

    QApplication::restoreOverrideCursor();
  }

  void clear_labels (Item_classification_base* classif)
  {
    classif->clear_labels();
  }

  void add_new_label (Item_classification_base* classif, const std::string& name)
  {
    add_new_label (LabelButton (dock_widget,
                                name.c_str(),
                                QColor (64 + rand() % 192,
                                        64 + rand() % 192,
                                        64 + rand() % 192),
                                get_shortcut (label_buttons.size(), name.c_str())));
    QColor color = classif->add_new_label (name.c_str());
    label_buttons.back().change_color (color);
  }

  void on_add_new_label_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }

    bool ok;
    QString name =
      QInputDialog::getText((QWidget*)mw,
                            tr("Add new labels"), // dialog title
                            tr("Names (separated by spaces):"), // field label
                            QLineEdit::Normal,
                            tr("label_%1").arg(label_buttons.size()),
                            &ok);
    if (!ok)
      return;

    std::istringstream iss (name.toStdString());

    std::string n;
    while (iss >> n)
      add_new_label (classif, n);

    add_label_button();
    update_plugin_from_item(classif);
  }

  void on_use_config_building_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }

    if (classif->number_of_labels() != 0)
    {
      QMessageBox::StandardButton reply
        = QMessageBox::question(nullptr, "Classification",
                                "Current labels will be discarded. Continue?",
                                QMessageBox::Yes|QMessageBox::No, QMessageBox::Yes);

      if (reply == QMessageBox::No)
        return;
    }
    clear_labels (classif);
    add_new_label (classif, "ground");
    add_new_label (classif, "vegetation");
    add_new_label (classif, "building");
    update_plugin_from_item (classif);
  }

  void on_use_config_roof_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }

    if (classif->number_of_labels() != 0)
    {
      QMessageBox::StandardButton reply
        = QMessageBox::question(nullptr, "Classification",
                                "Current labels will be discarded. Continue?",
                                QMessageBox::Yes|QMessageBox::No, QMessageBox::Yes);

      if (reply == QMessageBox::No)
        return;
    }
    clear_labels (classif);
    add_new_label (classif, "ground");
    add_new_label (classif, "vegetation");
    add_new_label (classif, "roof");
    add_new_label (classif, "facade");
    update_plugin_from_item (classif);
  }

  void on_use_las_config_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }

    if (classif->number_of_labels() != 0)
    {
      QMessageBox::StandardButton reply
        = QMessageBox::question(nullptr, "Classification",
                                "Current labels will be discarded. Continue?",
                                QMessageBox::Yes|QMessageBox::No, QMessageBox::Yes);

      if (reply == QMessageBox::No)
        return;
    }
    clear_labels (classif);
    add_new_label (classif, "ground");
    add_new_label (classif, "low_veget");
    add_new_label (classif, "med_veget");
    add_new_label (classif, "high_veget");
    add_new_label (classif, "building");
    add_new_label (classif, "noise");
    add_new_label (classif, "reserved");
    add_new_label (classif, "water");
    add_new_label (classif, "rail");
    add_new_label (classif, "road_surface");
    add_new_label (classif, "reserved_2");
    add_new_label (classif, "wire_guard");
    add_new_label (classif, "wire_conduct");
    add_new_label (classif, "trans_tower");
    add_new_label (classif, "wire_connect");
    add_new_label (classif, "bridge_deck");
    add_new_label (classif, "high_noise");
    update_plugin_from_item (classif);
  }

  void on_clear_labels_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }

    if (classif->number_of_labels() != 0)
    {
      QMessageBox::StandardButton reply
        = QMessageBox::question(nullptr, "Classification",
                                "Current labels will be discarded. Continue?",
                                QMessageBox::Yes|QMessageBox::No, QMessageBox::Yes);

      if (reply == QMessageBox::No)
        return;
    }
    clear_labels (classif);
    update_plugin_from_item (classif);
  }

  void on_reset_training_sets_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }

    classif->reset_training_sets();

    item_changed(classif->item());
  }

  void on_reset_training_set_of_selection_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }

    classif->reset_training_set_of_selection();

    item_changed(classif->item());
  }

  void on_reset_training_set_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }

    QPushButton* label_clicked = qobject_cast<QPushButton*>(QObject::sender()->parent()->parent());
    if (label_clicked == nullptr)
      std::cerr << "Error" << std::endl;
    else
    {
      int index = ui_widget.labelGrid->indexOf(label_clicked);
      int row_index, column_index, row_span, column_span;
      ui_widget.labelGrid->getItemPosition(index, &row_index, &column_index, &row_span, &column_span);

      int position = row_index * 3 + column_index;

      classif->reset_training_set
        (position);
    }

    item_changed(classif->item());
  }

  void on_validate_selection_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }

    classif->validate_selection();
  }

  void on_select_random_region_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }

    classif->select_random_region();
    item_changed(classif->item());

    CGAL::Three::Viewer_interface* viewer = CGAL::Three::Three::activeViewer();
    CGAL::Bbox_3 bbox = classif->bbox();
    const CGAL::qglviewer::Vec offset = CGAL::Three::Three::mainViewer()->offset();

    viewer->camera()->fitBoundingBox(CGAL::qglviewer::Vec (bbox.xmin(), bbox.ymin(), bbox.zmin()) + offset,
                                     CGAL::qglviewer::Vec (bbox.xmax(), bbox.ymax(), bbox.zmax()) + offset);



    viewer->camera()->setPivotPoint (CGAL::qglviewer::Vec ((bbox.xmin() + bbox.xmax()) / 2.,
                                                     (bbox.ymin() + bbox.ymax()) / 2.,
                                                     (bbox.zmin() + bbox.zmax()) / 2.) + offset);
  }

  void on_statistics_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
    {
      print_message("Error: there is no point set classification item!");
      return;
    }

    QApplication::setOverrideCursor(Qt::WaitCursor);
    std::string str = classif->feature_statistics();
    QApplication::restoreOverrideCursor();

    QMultipleInputDialog dialog ("Feature Statistics", mw);
    QLabel* text = dialog.add<QLabel> ("");
    text->setText(str.c_str());
    dialog.exec_no_cancel();
  }

  void on_switch_classifier_clicked()
  {
    QMultipleInputDialog dialog ("Which classifier do you want to use?", mw);

    QRadioButton* ethz = dialog.add<QRadioButton> (CGAL_CLASSIFICATION_ETHZ_ID);
    ethz->setChecked(true);

    QRadioButton* sowf = dialog.add<QRadioButton> (CGAL_CLASSIFICATION_SOWF_ID);

#ifdef CGAL_LINKED_WITH_OPENCV
    QRadioButton* opencv = dialog.add<QRadioButton> (CGAL_CLASSIFICATION_OPENCV_ID);
#endif

    if (dialog.exec() != QDialog::Accepted)
      return;

    if (ethz->isChecked())
      classifier->setText(CGAL_CLASSIFICATION_ETHZ_ID);
    else if (sowf->isChecked())
      classifier->setText(CGAL_CLASSIFICATION_SOWF_ID);
#ifdef CGAL_LINKED_WITH_OPENCV
    else if (opencv->isChecked())
      classifier->setText(CGAL_CLASSIFICATION_OPENCV_ID);
#endif

    if (sowf->isChecked())
    {
      dock_widget_adv->show();
      dock_widget_adv->raise();
    }
    else
      dock_widget_adv->hide();
  }

  void on_train_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }

    QMultipleInputDialog dialog ("Train Classifier", mw);

    int classifier = get_classifier();
    if (classifier == CGAL_CLASSIFICATION_SOWF_NUMBER) // Sum of Weighted Featuers
    {
      QSpinBox* trials = dialog.add<QSpinBox> ("Number of trials: ", "trials");
      trials->setRange (1, 99999);
      trials->setValue (800);
    }
    else if (classifier == CGAL_CLASSIFICATION_ETHZ_NUMBER
             || classifier == CGAL_CLASSIFICATION_OPENCV_NUMBER) // random forest
    {
      QSpinBox* trees = dialog.add<QSpinBox> ("Number of trees: ", "num_trees");
      trees->setRange (1, 9999);
      trees->setValue (25);
      QSpinBox* depth = dialog.add<QSpinBox> ("Maximum depth of tree: ", "max_depth");
      depth->setRange (1, 9999);
      depth->setValue (20);
    }

    if (dialog.exec() != QDialog::Accepted)
      return;

    QApplication::setOverrideCursor(Qt::WaitCursor);
    CGAL::Real_timer t;
    t.start();
    classif->train(classifier, dialog);
    t.stop();
    std::cerr << "Done in " << t.time() << " second(s)" << std::endl;
    QApplication::restoreOverrideCursor();
    update_plugin_from_item(classif);
  }

  char get_shortcut (std::size_t position, const char* name)
  {
    std::set<char> used_letters;

    used_letters.insert('t'); // used for "train"
    used_letters.insert('s'); // used for "random select"
    for (std::size_t i = 0; i < label_buttons.size(); ++ i)
      if (i != position)
        used_letters.insert (label_buttons[i].shortcut);

    std::size_t idx = 0;
    while (name[idx] != '\0')
    {
      if (std::isalpha(name[idx]) &&
          used_letters.find (std::tolower(name[idx])) == used_letters.end())
        return std::tolower(name[idx]);
      ++ idx;
    }

    char fallback = 'a';
    while (used_letters.find (fallback) != used_letters.end())
      ++ fallback;

    return fallback;
  }

  void add_new_label (const LabelButton& label_button)
  {
    label_buttons.push_back (label_button);
    int position = static_cast<int>(label_buttons.size()) - 1;

    int x = position / 3;
    int y = position % 3;

    ui_widget.labelGrid->addWidget (label_buttons.back().color_button, x, y);

    QAction* add_selection = label_buttons.back().menu->addAction ("Add selection to training set");

    add_selection->setShortcut(Qt::SHIFT | (Qt::Key_A + (label_button.shortcut - 'a')));
//    add_selection->setShortcut(Qt::Key_0 + label_buttons.size() - 1);

    connect(add_selection,  SIGNAL(triggered()), this,
            SLOT(on_add_selection_to_training_set_clicked()));

    QAction* reset = label_buttons.back().menu->addAction ("Reset training set");
    connect(reset,  SIGNAL(triggered()), this,
            SLOT(on_reset_training_set_clicked()));

    label_buttons.back().menu->addSeparator();

    QAction* change_color = label_buttons.back().menu->addAction ("Change color");
    connect(change_color,  SIGNAL(triggered()), this,
            SLOT(on_color_changed_clicked()));

    QAction* change_name = label_buttons.back().menu->addAction ("Change name");
    connect(change_name,  SIGNAL(triggered()), this,
            SLOT(on_name_changed_clicked()));

    QAction* create = label_buttons.back().menu->addAction ("Create point set item from labeled points");
    connect(create,  SIGNAL(triggered()), this,
            SLOT(on_create_point_set_item()));

    label_buttons.back().menu->addSeparator();

    QAction* remove_label = label_buttons.back().menu->addAction ("Remove label");
    connect(remove_label,  SIGNAL(triggered()), this,
            SLOT(on_remove_label_clicked()));

    ui_widget_adv.gridLayout->addWidget (label_buttons.back().label2, position + 1, 0);
    ui_widget_adv.gridLayout->addWidget (label_buttons.back().effect, position + 1, 2);

    connect(label_buttons.back().effect,  SIGNAL(currentIndexChanged(int)), this,
            SLOT(on_effect_changed(int)));
  }

  void add_label_button()
  {
    int position = static_cast<int>(label_buttons.size());
    int x = position / 3;
    int y = position % 3;

    label_button->setVisible (true);
    ui_widget.labelGrid->addWidget (label_button, x, y);
  }

  void on_remove_label_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }

    QPushButton* label_clicked = qobject_cast<QPushButton*>(QObject::sender()->parent()->parent());
    if (label_clicked == nullptr)
      std::cerr << "Error" << std::endl;
    else
    {
      int index = ui_widget.labelGrid->indexOf(label_clicked);
      int row_index, column_index, row_span, column_span;
      ui_widget.labelGrid->getItemPosition(index, &row_index, &column_index, &row_span, &column_span);

      int position = row_index * 3 + column_index;

      classif->remove_label (position);

      ui_widget.labelGrid->removeWidget (label_buttons[position].color_button);
      label_buttons[position].color_button->deleteLater();
      label_buttons[position].menu->deleteLater();

      ui_widget_adv.gridLayout->removeWidget (label_buttons[position].label2);
      delete label_buttons[position].label2;
      ui_widget_adv.gridLayout->removeWidget (label_buttons[position].effect);
      delete label_buttons[position].effect;

      if (label_buttons.size() > 1)
        for (int i = position + 1; i < static_cast<int>(label_buttons.size()); ++ i)
        {
          int position = i - 1;
          int x = position / 3;
          int y = position % 3;

          ui_widget.labelGrid->addWidget (label_buttons[i].color_button, x, y);
          ui_widget_adv.gridLayout->addWidget (label_buttons[i].label2, (int)i, 0);
          ui_widget_adv.gridLayout->addWidget (label_buttons[i].effect, (int)i, 2);
        }

      label_buttons.erase (label_buttons.begin() + position);
      add_label_button();
    }
    update_plugin_from_item(classif);
    item_changed(classif->item());
  }

  void on_color_changed_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }

    QPushButton* label_clicked = qobject_cast<QPushButton*>(QObject::sender()->parent()->parent());
    if (label_clicked == nullptr)
      std::cerr << "Error" << std::endl;
    else
    {
      int index = ui_widget.labelGrid->indexOf(label_clicked);
      int row_index, column_index, row_span, column_span;
      ui_widget.labelGrid->getItemPosition(index, &row_index, &column_index, &row_span, &column_span);

      int position = row_index * 3 + column_index;

      QColor color = label_buttons[position].color;
      color = QColorDialog::getColor(color, (QWidget*)mw, "Change color of label");

      if (!color.isValid())
        return;

      label_buttons[position].change_color (color);
      classif->change_label_color (position,
                                   color);
    }
    classif->update_color ();
    item_changed(classif->item());
  }

  void on_name_changed_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
    {
      print_message("Error: there is no point set classification item!");
      return;
    }

    QPushButton* label_clicked = qobject_cast<QPushButton*>(QObject::sender()->parent()->parent());
    if (label_clicked == nullptr)
      std::cerr << "Error" << std::endl;
    else
    {
      int index = ui_widget.labelGrid->indexOf(label_clicked);
      int row_index, column_index, row_span, column_span;
      ui_widget.labelGrid->getItemPosition(index, &row_index, &column_index, &row_span, &column_span);

      int position = row_index * 3 + column_index;

      bool ok;
      QString name =
        QInputDialog::getText((QWidget*)mw,
                              tr("Change name of label"), // dialog title
                              tr("New name:"), // field label
                              QLineEdit::Normal,
                              classif->label(position)->name().c_str(),
                              &ok);

      if (!ok)
        return;

      classif->change_label_name (position, name.toStdString());
    }

    update_plugin_from_item(classif);
    classif->update_color ();
    item_changed(classif->item());
  }

  void on_add_selection_to_training_set_clicked()
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }

    QPushButton* label_clicked = qobject_cast<QPushButton*>(QObject::sender()->parent()->parent());
    if (label_clicked == nullptr)
      std::cerr << "Error" << std::endl;
    else
    {
      int index = ui_widget.labelGrid->indexOf(label_clicked);
      int row_index, column_index, row_span, column_span;
      ui_widget.labelGrid->getItemPosition(index, &row_index, &column_index, &row_span, &column_span);

      int position = row_index * 3 + column_index;
      classif->add_selection_to_training_set
        (position);
    }

    item_changed(classif->item());
  }

  void on_selected_feature_changed(int v)
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
        return;

    if (classif->number_of_features() <= (std::size_t)v)
      return;

    Item_classification_base::Feature_handle
      att = classif->feature(v);

    if (att == Item_classification_base::Feature_handle())
      return;

    ui_widget_adv.feature_weight->setValue ((int)(1001. * 2. * std::atan(classif->weight(att)) / CGAL_PI));

    for (std::size_t i = 0; i < classif->number_of_labels(); ++ i)
      {
        CGAL::Classification::Sum_of_weighted_features_classifier::Effect
          eff = classif->effect (classif->label(i), att);
        if (eff == CGAL::Classification::Sum_of_weighted_features_classifier::PENALIZING)
          label_buttons[i].effect->setCurrentIndex(0);
        else if (eff == CGAL::Classification::Sum_of_weighted_features_classifier::NEUTRAL)
          label_buttons[i].effect->setCurrentIndex(1);
        else
          label_buttons[i].effect->setCurrentIndex(2);
      }
  }


  void on_feature_weight_changed(int v)
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }
    Item_classification_base::Feature_handle
      att = classif->feature(ui_widget_adv.selected_feature->currentIndex());

    if (att == Item_classification_base::Feature_handle())
      return;

    classif->set_weight(att, std::tan ((CGAL_PI/2.) * v / 1001.));

    for (std::size_t i = 0; i < label_buttons.size(); ++ i)
      label_buttons[i].effect->setEnabled(classif->weight(att) != 0.);
  }

  void on_effect_changed (int v)
  {
    Item_classification_base* classif
      = get_classification();
    if(!classif)
      {
        print_message("Error: there is no point set classification item!");
        return;
      }
    Item_classification_base::Feature_handle
      att = classif->feature(ui_widget_adv.selected_feature->currentIndex());

    if (att == Item_classification_base::Feature_handle())
      return;

    QComboBox* combo = qobject_cast<QComboBox*>(QObject::sender());
    for (std::size_t i = 0;i < label_buttons.size(); ++ i)
      if (label_buttons[i].effect == combo)
        {
          //          std::cerr << att->id() << " is ";
          if (v == 0)
            {
              classif->set_effect(classif->label(i),
                                  att, CGAL::Classification::Sum_of_weighted_features_classifier::PENALIZING);
            }
          else if (v == 1)
            {
              classif->set_effect(classif->label(i),
                                  att, CGAL::Classification::Sum_of_weighted_features_classifier::NEUTRAL);
            }
          else
            {
              classif->set_effect(classif->label(i),
                                  att, CGAL::Classification::Sum_of_weighted_features_classifier::FAVORING);
            }
          break;
        }
  }

private:
  Messages_interface* messages;
  QAction* actionClassification;

  QDockWidget* dock_widget;
  QDockWidget* dock_widget_adv;
  QAction* action_statistics;
  QAction* action_reset_local;
  QAction* action_reset;
  QAction* action_random_region;
  QAction* action_validate;

  QAction* classifier;
  QAction* action_train;
  QAction* action_run;
  QAction* action_run_smoothed;
  QAction* action_run_graphcut;
  QAction* action_save_config;
  QAction* action_load_config;

  std::vector<LabelButton> label_buttons;
  QPushButton* label_button;

  Ui::Classification ui_widget;
  Ui::ClassificationAdvanced ui_widget_adv;

  QColor color_att;

  typedef std::map<Scene_item*, Item_classification_base*> Item_map;
  Item_map item_map;


}; // end Polyhedron_demo_classification_plugin

#include "Classification_plugin.moc"
