/**
**
** @RDE_HEADER@
** Abstract Event Dispatcher for Qt5
** $Id$
** $HeadURL$
** $Author$
**
** -----------------------------------------------------------------------------------------------
**
** Hardware-Environment: Intel-PC
** Software-Environment: Windows 7, Qt 5.4. ArcGIS 10.2.5
**
** Language ........: C++ 11
**
** -----------------------------------------------------------------------------------------------
**
** Author ...........: Jörg Turla, SPD G, Tel. 3132
**
** -----------------------------------------------------------------------------------------------
**
** Notes .........:
**
**   28.04.2003, JT  : First edition for use with Qt4 in START Feature Editor fee
**   25.03.2015, JT  : Refactoring for use with Qt5
**
** -----------------------------------------------------------------------------------------------
*/

#include "abstract_event_dispatcher.h"
#include "gestures.h"

#include <assert.h>
#include <math.h>

#include <QtGui/QBitmap>

#include <QtGui/QKeyEvent>
#include <QtGui/QMouseEvent>
#include <QtGui/QWheelEvent>

#include <QtWidgets/QWidget>
#include <QtWidgets/QApplication>

#include <QtCore/QDebug> // for debugging only


namespace SituationMap { namespace RB
{


   QGestureRecognizer  * AbstractEventDispatcher::_applyGestureDetection = nullptr;
   unsigned int          AbstractEventDispatcher::_applyGestureID        = 0;


   AbstractEventDispatcher::AbstractEventDispatcher( QWidget * getEventsFrom ) 
      : QObject(getEventsFrom)
      , _getEventsFrom(getEventsFrom)
      , _cursorIsInWidget(false)
      , _ignoreMouseMoveTimestamp()
      , _synthesisTouchFromMouseEvents(false)
      , _deleteRequested(false)
      , _hasGrab(false)
      , _finishFlag(false)
      , _activeEvent(false)
      , _dispatcherCursor()
      , _whatsThisBackup()
      , _eventActions(nullptr)
   {
      initDispatcher();
   } /* AbstractEventDispatcher::AbstractEventDispatcher */ 


   AbstractEventDispatcher::AbstractEventDispatcher( QWidget * getEventsFrom, EventActionInterface * eventActions )
      : QObject(getEventsFrom)
      , _getEventsFrom(getEventsFrom)
      , _cursorIsInWidget(false)
      , _ignoreMouseMoveTimestamp()
      , _synthesisTouchFromMouseEvents(false)
      , _deleteRequested(false)
      , _hasGrab(false)
      , _finishFlag(false)
      , _activeEvent(false)
      , _dispatcherCursor()
      , _whatsThisBackup()
      , _eventActions(eventActions)
     
   {
      initDispatcher();
   } /* AbstractEventDispatcher::AbstractEventDispatcher */ 


    void AbstractEventDispatcher::initDispatcher()
    {
      _restoreCursor = true;

      /* The methode QWidget::ownCursor doesn't exist any more.
       * Try to find out if the inherited from parent 
       */

      // _restoreCursor = getEventsFrom->ownCursor();
  
      if (_restoreCursor)
      {
         _cursorToRestore = getCursorFromWidget();
      }
      _restoreMouseTracking = _getEventsFrom->hasMouseTracking();

      // just a test exe, but remove process Events
      //   QCoreApplication::process Events ( );   /// removePostedEvents( _getEventsFrom );

      _getEventsFrom->setMouseTracking(true);
      _getEventsFrom->raise();
      _getEventsFrom->installEventFilter(this);

      _synthesisTouchFromMouseEvents = QCoreApplication::testAttribute( Qt::AA_SynthesizeTouchForUnhandledMouseEvents );
      QCoreApplication::setAttribute( Qt::AA_SynthesizeTouchForUnhandledMouseEvents, false );
      QCoreApplication::setAttribute( Qt::AA_SynthesizeMouseForUnhandledTouchEvents, true  );
#ifdef NEVER
      static const Qt::GestureType gestures[] = { Qt::GestureType::TapGesture
                                                , Qt::GestureType::TapAndHoldGesture
                                                , Qt::GestureType::PanGesture
                                                , Qt::GestureType::PinchGesture
                                                , Qt::GestureType::SwipeGesture };

      for (auto gestureType : gestures) _getEventsFrom->grabGesture(gestureType);

      if (_applyGestureDetection == nullptr) 
      {
         _applyGestureDetection = new ApplyGestureRecognizer();
         _applyGestureID        = QGestureRecognizer::registerRecognizer( _applyGestureDetection );
      }
      
      _getEventsFrom->grabGesture( (Qt::GestureType)_applyGestureID );
      _getEventsFrom->setAttribute( Qt::WA_AcceptTouchEvents, true );
#endif
   } /* AbstractEventDispatcher::initDispatcher */


   AbstractEventDispatcher::~AbstractEventDispatcher()
   {

      _finishFlag = true;
   
      if (_getEventsFrom)
      {
         _getEventsFrom->removeEventFilter(this);
         _getEventsFrom->setMouseTracking( _restoreMouseTracking );
  
         ungrab();

         if (!_whatsThisBackup.isNull())
         {
            _getEventsFrom->setWhatsThis(_whatsThisBackup);
         }
      }
      QCoreApplication::setAttribute( Qt::AA_SynthesizeTouchForUnhandledMouseEvents, _synthesisTouchFromMouseEvents );

   } /* AbstractEventDispatcher::~AbstractEventDispatcher */


   void AbstractEventDispatcher::onDo_delete()
   {
     if (_deleteRequested) return;
     _deleteRequested = true;
     QObject::deleteLater();
   } /* AbstractEventDispatcher::onDo_delete */


   void AbstractEventDispatcher::KickTheBucket()
   {
      if (_getEventsFrom == nullptr) return;

      _finishFlag = true; 
 
      unlinkEventDispatcher();

      _getEventsFrom->removeEventFilter(this);
      _getEventsFrom->setMouseTracking( _restoreMouseTracking );
  
      ungrab();

      if (!_whatsThisBackup.isNull())
      {
         _getEventsFrom->setWhatsThis(_whatsThisBackup);
      }

      _getEventsFrom = nullptr;

      emit signalKickTheBucket();

      QCoreApplication::flush();
      // just a test exe, but remove process Events
      //  QCoreApplication::process Events();      // dispatch window system events

      onDo_delete();

   } /* AbstractEventDispatcher::KickTheBucket */


   void AbstractEventDispatcher::onDo_kickTheBucket() { KickTheBucket(); }


   void AbstractEventDispatcher::setWhatsThis(const QString & whatsThis)
   {
      if (_whatsThisBackup.isNull())
      {
         _whatsThisBackup = _getEventsFrom->whatsThis();
      }
      _getEventsFrom->setWhatsThis(whatsThis);
   } /* AbstractEventDispatcher::setWhatsThis */



   void AbstractEventDispatcher::grab()
   {
      if (_hasGrab) return;
      _hasGrab = true;
     
      setCursorToWidget( _dispatcherCursor );
      _getEventsFrom -> setFocus();
   } /* AbstractEventDispatcher::Grab */


   void AbstractEventDispatcher::ungrab()
   {
      if (!_hasGrab) return;

      _hasGrab = false;
      if (_restoreCursor)
      {  
         setCursorToWidget( _cursorToRestore );
      }
      // else _getEventsFrom -> unsetCursor();

      _getEventsFrom -> clearFocus();

   } /* AbstractEventDispatcher::Ungrab */


   bool AbstractEventDispatcher::eventFilter( QObject * widget, QEvent * e )
   {
      if (widget != ((QObject*)_getEventsFrom)) return false;

     
      return false;
   } /* AbstractEventDispatcher::eventFilter */


   void AbstractEventDispatcher::setCursorToWidget( const QCursor & cursor )
   {
     /* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      * The cursor handling of QGraphicView are not free of bugs. If it tries to restore the default cursor after setting a special cursor for one item
      * it can happend that the restored cursor is not the last cursor that was set with setCursor function because the internal stored restore cursor is
      * not updated with setCursor function. As work around a mouse move event is send to the widget to reset cursor handling.
      * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
    
     const QPoint & currentCursorPosition = _getEventsFrom->mapFromGlobal( QCursor::pos() );  

#ifdef ShowBug
     QMouseEvent && mouseEvent            = QMouseEvent( QEvent::Type::MouseMove, QPointF(-1,-1), Qt::MouseButton::NoButton, Qt::MouseButtons(), Qt::KeyboardModifier::NoModifier );

     _ignoreMouseMoveTimestamp = mouseEvent.timestamp();

     QCoreApplication::sendEvent(_getEventsFrom, &mouseEvent );
     QCoreApplication::process Events();

     _getEventsFrom -> setCursor( cursor );

     if (_cursorIsInWidget)
     {
        mouseEvent = QMouseEvent( QEvent::Type::MouseMove, currentCursorPosition, Qt::MouseButton::NoButton, Qt::MouseButtons(), Qt::KeyboardModifier::NoModifier );
        QCoreApplication::sendEvent(_getEventsFrom, &mouseEvent );
     }
     QCoreApplication::process Events();
     _getEventsFrom -> update();
#else
     _getEventsFrom -> setCursor( cursor );
#endif
   } /* AbstractEventDispatcher::setCursorToWidget */

   
   QCursor AbstractEventDispatcher::getCursorFromWidget()
   {
      const QPoint & currentCursorPosition = _getEventsFrom->mapFromGlobal( QCursor::pos() );

#ifdef ShowBug
      QMouseEvent && mouseEvent = QMouseEvent( QEvent::Type::MouseMove, QPointF(-1,-1), Qt::MouseButton::NoButton, Qt::MouseButtons(), Qt::KeyboardModifier::NoModifier );
     
      _ignoreMouseMoveTimestamp = mouseEvent.timestamp();
 
      QCoreApplication::sendEvent(_getEventsFrom, &mouseEvent );
      QCoreApplication::process Events();

      const QCursor & currentCursor =  _getEventsFrom->cursor();

      if (_cursorIsInWidget)
      {
         mouseEvent = QMouseEvent( QEvent::Type::MouseMove, currentCursorPosition, Qt::MouseButton::NoButton, Qt::MouseButtons(), Qt::KeyboardModifier::NoModifier );
         QCoreApplication::sendEvent(_getEventsFrom, &mouseEvent );
      }
      QCoreApplication::process Events();
      _getEventsFrom -> update();
#else
       const QCursor & currentCursor =  _getEventsFrom->cursor();
#endif
      return currentCursor;
   } /* AbstractEventDispatcher::getCursorFromWidget */


} } /* namespace SituationMap::RB */