// $Id$
//-----------------------------------------------------------------------
//       The GSI Online Offline Object Oriented (Go4) Project
//         Experiment Data Processing at EE department, GSI
//-----------------------------------------------------------------------
// Copyright (C) 2000- GSI Helmholtzzentrum fuer Schwerionenforschung GmbH
//                     Planckstr. 1, 64291 Darmstadt, Germany
// Contact:            http://go4.gsi.de
//-----------------------------------------------------------------------
// This software can be used under the license agreements as stated
// in Go4License.txt file which is part of the distribution.
//-----------------------------------------------------------------------

#include "TGo4MdiArea.h"

#include "TROOT.h"
#include "TCanvas.h"

#include <QMdiSubWindow>

#include "TGo4ViewPanel.h"
#include "TGo4QSettings.h"

TGo4MdiArea* TGo4MdiArea::gInstance = nullptr;

TGo4MdiArea* TGo4MdiArea::Instance()
{
   return gInstance;
}

TGo4MdiArea::TGo4MdiArea(QWidget *parent) :
   QMdiArea(parent)
{
   setSizeIncrement( QSize( 100, 100 ) );
   setBaseSize( QSize( 100, 100 ) );

   QObject::connect(this, &TGo4MdiArea::subWindowActivated, this, &TGo4MdiArea::subWindowActivatedSlot);

   if (!gInstance) gInstance = this;
}

TGo4MdiArea::~TGo4MdiArea()
{
   if (gInstance == this)
      gInstance = nullptr;
}

TPad *TGo4MdiArea::GetSelectedPad()
{
   return fxSelectedPad;
}

void TGo4MdiArea::SetSelectedPad(TPad *pad)
{
   fxSelectedPad = pad;
   gROOT->SetSelectedPad(pad);
   gPad = pad;
}

TGo4ViewPanel *TGo4MdiArea::GetActivePanel()
{
   return fxActivePanel;
}

QMdiSubWindow *TGo4MdiArea::AddGo4SubWindow(QWidget *widget, Qt::WindowFlags flags)
{
   QMdiSubWindow *sub = addSubWindow(widget, flags);
   // JAM make window behavior configurable in Go4 for all Qt versions.
   if (go4sett->getMoveSubwindowRubberBand()) {
      sub->setOption(QMdiSubWindow::RubberBandResize);
      sub->setOption(QMdiSubWindow::RubberBandMove); // JAM required for qt5 performance
   }
   return sub;
}

void TGo4MdiArea::subWindowActivatedSlot(QMdiSubWindow* sub)
{
   TGo4ViewPanel *panel = sub ? dynamic_cast<TGo4ViewPanel *>(sub->widget()) : nullptr;

   if (panel && (fxActivePanel != panel))
      panel->SetActivePad(panel->GetActivePad());
}

TGo4ViewPanel *TGo4MdiArea::FindOtherPanel(TGo4ViewPanel *not_this)
{
   QList<QMdiSubWindow *> windows = subWindowList();
   for (int i = 0; i < windows.count(); ++i) {
      TGo4ViewPanel *panel = dynamic_cast<TGo4ViewPanel *>(windows.at(i)->widget());
      if (panel && (panel != not_this)) return panel;
   }

   return nullptr;
}

void TGo4MdiArea::ResponseOnPanelEvent(int funcid, TGo4ViewPanel *panel, TPad *pad)
{
   if (!panel)
      return;

   switch (funcid) {
      case QGo4Widget::panel_Activated: {
         if ((fxActivePanel != panel) && fxActivePanel)
            fxActivePanel->SetActivePad(nullptr);

         bool changed = (fxActivePanel != panel) || (fxActivePad != pad);
         fxActivePanel = panel;
         fxActivePad = pad;

         if (changed)
            emit panelSignal(panel, pad, QGo4Widget::panel_Activated);

         break;
      }

      case QGo4Widget::panel_Modified: {
         emit panelSignal(panel, pad, QGo4Widget::panel_Modified);
         break;
      }

      case QGo4Widget::panel_Updated: {
         emit panelSignal(panel, pad, QGo4Widget::panel_Updated);
         if ((panel == fxActivePanel) && (pad == fxActivePad))
            emit panelSignal(panel, pad, QGo4Widget::panel_ActiveUpdated);
         break;
      }

      case QGo4Widget::panel_PadDeleted: {
         if (GetSelectedPad() == pad)
            SetSelectedPad(nullptr);
         if (fxActivePad == pad)
            fxActivePad = nullptr;
         emit panelSignal(panel, pad, QGo4Widget::panel_PadDeleted);
         break;
      }

      case QGo4Widget::panel_Deleted: {
         if (GetSelectedPad())
            if (panel->IsPanelPad(GetSelectedPad()))
               SetSelectedPad(nullptr);

         if (fxActivePanel == panel) {
            fxActivePanel = nullptr;
            fxActivePad = nullptr;
         }

#ifdef __GO4WEB__
         // try to keep gPad - nullptr can have problem when running TWebCanvas
         if (!gPad || panel->IsPanelPad((TPad *)gPad)) {
            TGo4ViewPanel *other = FindOtherPanel(panel);

            SetSelectedPad(other ? other->GetCanvas() : nullptr);
         }
#endif

         emit panelSignal(panel, pad, QGo4Widget::panel_Deleted);

         break;
      }
   }
}