/**
 * @RDE_HEADER@
 * ComboBox, optimized for tablets (bigger dropdown/popup and more comfortable completer)
 * $Id$
 * $HeadURL$
 * $Author$
 *
 * Created by Mike Wille, SLSE, 2016-03-09
 */

#include "lts_combo_box.h"
#include "lts_selection_popup.h"
#include "lts_message_dialog.h"

#include <QGuiApplication>
#include <QShowEvent>

//#define NEVER
#ifdef NEVER
#  include <QDebug>
#endif // NEVER

namespace LtsWidgets
{

bool LtsComboBox::s_useSelectionDialog = false;

LtsComboBox::LtsComboBox(QWidget *parent)
  : QComboBox(parent)
  , m_currentIndex(-1)
{
  connect(this, &LtsComboBox::signalExternallyChanged,
          this, &LtsComboBox::signalRefill); // sig on sig (to fetch cbx as sender)
}

void LtsComboBox::setUseSelectionDialog(bool bUseSelectionDialog)
{
  s_useSelectionDialog = bUseSelectionDialog;
}

void LtsComboBox::showEvent(QShowEvent *e)
{
  QComboBox::showEvent(e);

  m_currentIndex = currentIndex();
}

void LtsComboBox::enterEvent(QEvent *e)
{
  BaseClass::enterEvent(e);
  emit signalEnterEvent();
}

void LtsComboBox::leaveEvent(QEvent *e)
{
  BaseClass::leaveEvent(e);
  emit signalLeaveEvent();
}

void LtsComboBox::showPopup()
{
  bool bUseSelectionDialog = s_useSelectionDialog;
  if (QGuiApplication::queryKeyboardModifiers() == Qt::ControlModifier)
    bUseSelectionDialog = !bUseSelectionDialog;
  if (!bUseSelectionDialog)
  {
    QComboBox::showPopup(); // show original popup when CTRL is pressed
    return;
  }

  if (!model()->rowCount()) // nothing to show? tell the user.
  {
    LtsWidgets::LtsMessageDialog::showMessage(this, tr("There are no items available!"));
    return;
  }

  // create the touch-friendly, screen-centered custom popup and show it
  LtsSelectionPopup* popup = new LtsSelectionPopup(model(), currentIndex(), this);
  popup->setAttribute(Qt::WA_DeleteOnClose); // dialog must delete itself, as there is no  Dialog Helper

#ifdef NEVER
  // debugging :
  //  // highlighted -> UserInteraction
//  connect(popup, static_cast<void (LtsSelectionPopup::*)(int)>(&LtsSelectionPopup::highlighted), this, [](int idx){
//    qCritical() << " LtsComboBox: called: highlighted(int), idx=" << idx;
//  });

  // currentIndexChanged -> programmatically & UserInteraction
  connect(popup, static_cast<void (LtsSelectionPopup::*)(int)>(&LtsSelectionPopup::currentIndexChanged), this, [](int idx){
    qCritical() << " LtsComboBox: called: currentIndexChanged(int), idx=" << idx;
  });

  // activated -> UserInteraction
  connect(popup, static_cast<void (LtsSelectionPopup::*)(int)>(&LtsSelectionPopup::activated), this, [](int idx){
    qCritical() << " LtsComboBox: called: activated(int), idx=" << idx;
  });
  // : debugging
#endif // NEVER

  // Although we derive from QComboBox, there seems to be no signal emitted implicitly.
  // Therefore we have to listen to our popup:
  connect(popup, &LtsSelectionPopup::currentIndexChanged,
          this, &LtsComboBox::userChangedIndex);                                   // listen on changes
  connect(popup, &LtsSelectionPopup::activated,
          this, static_cast<void (LtsComboBox::*)(int)>(&LtsComboBox::activated)); // SIGNAL on SIGNAL !

  popup->show();
}


void LtsComboBox::userChangedIndex(int index)
{
  m_currentIndex = index;
  setCurrentIndex(index);
}


bool LtsComboBox::hasValueChanged() const
{
  if (m_currentIndex == -1)
    return false;
  return !(currentIndex() == m_currentIndex);
}

} // namespace LtsWidgets