/* This file is part of the KDE libraries
    Copyright (C) 2004 Antonio Larrosa <larrosa@kde.org

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public License
    along with this library; see the file COPYING.LIB.  If not, write to
    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
    Boston, MA 02110-1301, USA.
*/

/* NOTE: There are two copies of this .h and the .cpp file, with subtle differences.
 * One copy is in kdelibs/kdeui, and the other copy is in kdepim/libkdepim
 * This is because kdepim has to remain backwards compatible.  Any changes
 * to either file should be made to the other.
 */

#include "kpixmapregionselectorwidget.h"
#include <QtGui/QPainter>
#include <QtGui/QColor>
#include <QtGui/QImage>
#include <QLabel>
#include <QtGui/QLayout>
#include <QRubberBand>
#include <kdebug.h>
#include <kicon.h>
#include <klocale.h>
#include <kmenu.h>
#include <kaction.h>
#include <stdlib.h>
#include <QtGui/QCursor>
#include <QtGui/QApplication>
#include <QMouseEvent>
#include "kactioncollection.h"

class KPixmapRegionSelectorWidget::Private
{
public:
  Private(KPixmapRegionSelectorWidget *q): q(q) {}
  
  KPixmapRegionSelectorWidget *q;
  
  /**
   * Recalculates the pixmap that is shown based on the current selected area,
   * the original image, etc.
   */
  void updatePixmap();
  
  QRect calcSelectionRectangle( const QPoint &startPoint, const QPoint & endPoint );
  
  enum CursorState { None=0, Resizing, Moving };
  CursorState m_state;
  
  QPixmap m_unzoomedPixmap;
  QPixmap m_originalPixmap;
  QPixmap m_linedPixmap;
  QRect   m_selectedRegion;
  QLabel *m_label;
  
  QPoint m_tempFirstClick;
  double m_forcedAspectRatio;
  
  int m_maxWidth, m_maxHeight;
  double m_zoomFactor;
  
  QRubberBand *m_rubberBand;  
};

KPixmapRegionSelectorWidget::KPixmapRegionSelectorWidget( QWidget *parent)
    : QWidget( parent ), d(new Private(this))
{
   QHBoxLayout * hboxLayout=new QHBoxLayout( this );

   hboxLayout->addStretch();
   QVBoxLayout * vboxLayout=new QVBoxLayout();
   hboxLayout->addItem(vboxLayout);

   vboxLayout->addStretch();
   d->m_label = new QLabel(this);
   d->m_label->setAttribute(Qt::WA_NoSystemBackground,true);//setBackgroundMode( Qt::NoBackground );
   d->m_label->installEventFilter( this );

   vboxLayout->addWidget(d->m_label);
   vboxLayout->addStretch();

   hboxLayout->addStretch();

   d->m_forcedAspectRatio=0;

   d->m_zoomFactor=1.0;
   d->m_rubberBand = new QRubberBand(QRubberBand::Rectangle, d->m_label);
   d->m_rubberBand->hide();
}

KPixmapRegionSelectorWidget::~KPixmapRegionSelectorWidget()
{
  delete d;
}

QPixmap KPixmapRegionSelectorWidget::pixmap() const
{
  return d->m_unzoomedPixmap;
}

void KPixmapRegionSelectorWidget::setPixmap( const QPixmap &pixmap )
{
   Q_ASSERT(!pixmap.isNull()); //This class isn't designed to deal with null pixmaps.
   d->m_originalPixmap = pixmap;
   d->m_unzoomedPixmap = pixmap;
   d->m_label->setPixmap( pixmap );
   resetSelection();
}

void KPixmapRegionSelectorWidget::resetSelection()
{
   d->m_selectedRegion = d->m_originalPixmap.rect();
   d->m_rubberBand->hide();
   d->updatePixmap();
}

QRect KPixmapRegionSelectorWidget::selectedRegion() const
{
     return d->m_selectedRegion;
}

void KPixmapRegionSelectorWidget::setSelectedRegion(const QRect &rect)
{
   if (!rect.isValid()) resetSelection();
   else
   {
      d->m_selectedRegion=rect;
      d->updatePixmap();

      QRect r=unzoomedSelectedRegion();
   }
}

void KPixmapRegionSelectorWidget::Private::updatePixmap()
{
   Q_ASSERT(!m_originalPixmap.isNull());
   if (m_originalPixmap.isNull()) { m_label->setPixmap(m_originalPixmap); return; }
   if (m_selectedRegion.width()>m_originalPixmap.width()) m_selectedRegion.setWidth( m_originalPixmap.width() );
   if (m_selectedRegion.height()>m_originalPixmap.height()) m_selectedRegion.setHeight( m_originalPixmap.height() );

   QPainter painter;
   if (m_linedPixmap.isNull())
   {
     m_linedPixmap = m_originalPixmap;
     QPainter p(&m_linedPixmap);
     p.setCompositionMode(QPainter::CompositionMode_SourceAtop);
     p.fillRect(m_linedPixmap.rect(), QColor(0, 0, 0, 100));
   }

   QPixmap pixmap = m_linedPixmap;
   painter.begin(&pixmap);
   painter.drawPixmap( m_selectedRegion.topLeft(),
        m_originalPixmap, m_selectedRegion );


   painter.end();

   m_label->setPixmap(pixmap);

   qApp->sendPostedEvents(0,QEvent::LayoutRequest);

   if (m_selectedRegion == m_originalPixmap.rect())//d->m_label->rect()) //### CHECK!
        m_rubberBand->hide();
   else
   {
        m_rubberBand->setGeometry(QRect(m_selectedRegion.topLeft(),
                                        m_selectedRegion.size()));

/*        m_rubberBand->setGeometry(QRect(m_label -> mapToGlobal(m_selectedRegion.topLeft()),
                                        m_selectedRegion.size()));
*/
        if (m_state!=None) m_rubberBand->show();
   }

}


KMenu *KPixmapRegionSelectorWidget::createPopupMenu()
{
    KMenu *popup=new KMenu(this );
    KActionCollection *actions=new KActionCollection(popup);
    popup->setObjectName( "PixmapRegionSelectorPopup");
    popup->addTitle(i18n("Image Operations"));

    QAction *action = actions->addAction("rotateclockwise");
    action->setText(i18n("&Rotate Clockwise"));
    action->setIcon( KIcon( "object-rotate-right" ) );
    connect( action, SIGNAL( triggered( bool ) ), this, SLOT(rotateClockwise()) );

    popup->addAction(action);

    action = actions->addAction("rotatecounterclockwise");
    action->setText(i18n("Rotate &Counterclockwise"));
    action->setIcon( KIcon( "object-rotate-left" ) );
    connect( action, SIGNAL( triggered( bool ) ), this, SLOT(rotateCounterclockwise()) );

    popup->addAction(action);

/*
   I wonder if it would be appropriate to have here an "Open with..." option to
   edit the image (antlarr)
*/
    return popup;
}

void KPixmapRegionSelectorWidget::rotate(RotateDirection direction)
{
   int w=d->m_originalPixmap.width();
   int h=d->m_originalPixmap.height();
   QImage img=d->m_unzoomedPixmap.toImage();
   if(direction == Rotate90)
       img = img.transformed(QTransform().rotate(90.0));
   else if(direction == Rotate180)
       img = img.transformed(QTransform().rotate(180.0));
   else
       img = img.transformed(QTransform().rotate(270.0));

   d->m_unzoomedPixmap=QPixmap::fromImage(img);

   img=d->m_originalPixmap.toImage();
   if(direction == Rotate90)
       img = img.transformed(QTransform().rotate(90.0));
   else if(direction == Rotate180)
       img = img.transformed(QTransform().rotate(180.0));
   else
       img = img.transformed(QTransform().rotate(270.0));

   d->m_originalPixmap=QPixmap::fromImage(img);

   d->m_linedPixmap=QPixmap();

   if (d->m_forcedAspectRatio>0 && d->m_forcedAspectRatio!=1)
      resetSelection();
   else
   {
      switch (direction)
      {
         case ( Rotate90 ):
            {
              int x=h-d->m_selectedRegion.y()-d->m_selectedRegion.height();
              int y=d->m_selectedRegion.x();
              d->m_selectedRegion.setRect(x, y, d->m_selectedRegion.height(), d->m_selectedRegion.width() );
              d->updatePixmap();
//              qApp->sendPostedEvents(0,QEvent::LayoutRequest);
//              updatePixmap();

            } break;
         case ( Rotate270 ):
            {
              int x=d->m_selectedRegion.y();
              int y=w-d->m_selectedRegion.x()-d->m_selectedRegion.width();
              d->m_selectedRegion.setRect(x, y, d->m_selectedRegion.height(), d->m_selectedRegion.width() );
              d->updatePixmap();
//              qApp->sendPostedEvents(0,QEvent::LayoutRequest);
//              updatePixmap();
            } break;
         default: resetSelection();
      }
   }

   emit pixmapRotated();
}

void KPixmapRegionSelectorWidget::rotateClockwise()
{
   rotate(Rotate90);
}

void KPixmapRegionSelectorWidget::rotateCounterclockwise()
{
   rotate(Rotate270);
}

bool KPixmapRegionSelectorWidget::eventFilter(QObject *obj, QEvent *ev)
{
   if ( ev->type() == QEvent::MouseButtonPress )
   {
      QMouseEvent *mev= (QMouseEvent *)(ev);
      //kDebug() << QString("click at  %1,%2").arg( mev->x() ).arg( mev->y() );

      if ( mev->button() == Qt::RightButton )
      {
         KMenu *popup = createPopupMenu( );
         popup->exec( mev->globalPos() );
         delete popup;
         return true;
      }

      QCursor cursor;

      if ( d->m_selectedRegion.contains( mev->pos() )
          && d->m_selectedRegion!=d->m_originalPixmap.rect() )
      {
         d->m_state=Private::Moving;
         cursor.setShape( Qt::SizeAllCursor );
         d->m_rubberBand->show();
      }
      else
      {
         d->m_state=Private::Resizing;
         cursor.setShape( Qt::CrossCursor );
      }
      QApplication::setOverrideCursor(cursor);

      d->m_tempFirstClick=mev->pos();


      return true;
   }

   if ( ev->type() == QEvent::MouseMove )
   {
      QMouseEvent *mev= (QMouseEvent *)(ev);

      //kDebug() << QString("move to  %1,%2").arg( mev->x() ).arg( mev->y() );

      if ( d->m_state == Private::Resizing )
      {
         setSelectedRegion (
              d->calcSelectionRectangle( d->m_tempFirstClick, mev->pos() ) );
      }
      else if (d->m_state == Private::Moving )
      {
         int mevx = mev->x();
         int mevy = mev->y();
         bool mouseOutside=false;
         if ( mevx < 0 )
         {
           d->m_selectedRegion.translate(-d->m_selectedRegion.x(),0);
           mouseOutside=true;
         }
         else if ( mevx > d->m_originalPixmap.width() )
         {
           d->m_selectedRegion.translate(d->m_originalPixmap.width()-d->m_selectedRegion.width()-d->m_selectedRegion.x(),0);
           mouseOutside=true;
         }
         if ( mevy < 0 )
         {
           d->m_selectedRegion.translate(0,-d->m_selectedRegion.y());
           mouseOutside=true;
         }
         else if ( mevy > d->m_originalPixmap.height() )
         {
           d->m_selectedRegion.translate(0,d->m_originalPixmap.height()-d->m_selectedRegion.height()-d->m_selectedRegion.y());
           mouseOutside=true;
         }
         if (mouseOutside) { d->updatePixmap(); return true; };

         d->m_selectedRegion.translate( mev->x()-d->m_tempFirstClick.x(),
                                  mev->y()-d->m_tempFirstClick.y() );

         // Check that the region has not fallen outside the image
         if (d->m_selectedRegion.x() < 0)
            d->m_selectedRegion.translate(-d->m_selectedRegion.x(),0);
         else if (d->m_selectedRegion.right() > d->m_originalPixmap.width())
            d->m_selectedRegion.translate(-(d->m_selectedRegion.right()-d->m_originalPixmap.width()),0);

         if (d->m_selectedRegion.y() < 0)
            d->m_selectedRegion.translate(0,-d->m_selectedRegion.y());
         else if (d->m_selectedRegion.bottom() > d->m_originalPixmap.height())
            d->m_selectedRegion.translate(0,-(d->m_selectedRegion.bottom()-d->m_originalPixmap.height()));

         d->m_tempFirstClick=mev->pos();
         d->updatePixmap();
      }
      return true;
   }

   if ( ev->type() == QEvent::MouseButtonRelease )
   {
      QMouseEvent *mev= (QMouseEvent *)(ev);

      if ( d->m_state == Private::Resizing && mev->pos() == d->m_tempFirstClick)
         resetSelection();

      d->m_state=Private::None;
      QApplication::restoreOverrideCursor();
      d->m_rubberBand->hide();
      return true;
   }

   QWidget::eventFilter(obj, ev);
   return false;
}

QRect KPixmapRegionSelectorWidget::Private::calcSelectionRectangle( const QPoint & startPoint, const QPoint & _endPoint )
{
   QPoint endPoint = _endPoint;
   if ( endPoint.x() < 0 ) endPoint.setX(0);
   else if ( endPoint.x() > m_originalPixmap.width() ) endPoint.setX(m_originalPixmap.width());
   if ( endPoint.y() < 0 ) endPoint.setY(0);
   else if ( endPoint.y() > m_originalPixmap.height() ) endPoint.setY(m_originalPixmap.height());
   int w=abs(startPoint.x()-endPoint.x());
   int h=abs(startPoint.y()-endPoint.y());

   if (m_forcedAspectRatio>0)
   {
      double aspectRatio=w/double(h);

      if (aspectRatio>m_forcedAspectRatio)
         h=(int)(w/m_forcedAspectRatio);
      else
         w=(int)(h*m_forcedAspectRatio);
   }

   int x,y;
   if ( startPoint.x() < endPoint.x() )
     x=startPoint.x();
   else
     x=startPoint.x()-w;
   if ( startPoint.y() < endPoint.y() )
     y=startPoint.y();
   else
     y=startPoint.y()-h;

   if (x<0)
   {
      w+=x;
      x=0;
      h=(int)(w/m_forcedAspectRatio);

      if ( startPoint.y() > endPoint.y() )
        y=startPoint.y()-h;
   }
   else if (x+w>m_originalPixmap.width())
   {
      w=m_originalPixmap.width()-x;
      h=(int)(w/m_forcedAspectRatio);

      if ( startPoint.y() > endPoint.y() )
        y=startPoint.y()-h;
   }
   if (y<0)
   {
      h+=y;
      y=0;
      w=(int)(h*m_forcedAspectRatio);

      if ( startPoint.x() > endPoint.x() )
        x=startPoint.x()-w;
   }
   else if (y+h>m_originalPixmap.height())
   {
      h=m_originalPixmap.height()-y;
      w=(int)(h*m_forcedAspectRatio);

      if ( startPoint.x() > endPoint.x() )
        x=startPoint.x()-w;
   }

   return QRect(x,y,w,h);
}

QRect KPixmapRegionSelectorWidget::unzoomedSelectedRegion() const
{
  return QRect((int)(d->m_selectedRegion.x()/d->m_zoomFactor),
               (int)(d->m_selectedRegion.y()/d->m_zoomFactor),
               (int)(d->m_selectedRegion.width()/d->m_zoomFactor),
               (int)(d->m_selectedRegion.height()/d->m_zoomFactor));
}

QImage KPixmapRegionSelectorWidget::selectedImage() const
{
   QImage origImage=d->m_unzoomedPixmap.toImage();
   return origImage.copy(unzoomedSelectedRegion());
}

void KPixmapRegionSelectorWidget::setSelectionAspectRatio(int width, int height)
{
   d->m_forcedAspectRatio=width/double(height);
}

void KPixmapRegionSelectorWidget::setFreeSelectionAspectRatio()
{
   d->m_forcedAspectRatio=0;
}

void KPixmapRegionSelectorWidget::setMaximumWidgetSize(int width, int height)
{
   d->m_maxWidth=width;
   d->m_maxHeight=height;

   if (d->m_selectedRegion == d->m_originalPixmap.rect()) d->m_selectedRegion=QRect();
   d->m_originalPixmap=d->m_unzoomedPixmap;

//   kDebug() << QString(" original Pixmap :") << d->m_originalPixmap.rect();
//   kDebug() << QString(" unzoomed Pixmap : %1 x %2 ").arg(d->m_unzoomedPixmap.width()).arg(d->m_unzoomedPixmap.height());

   if ( !d->m_originalPixmap.isNull() &&
       ( d->m_originalPixmap.width() > d->m_maxWidth ||
         d->m_originalPixmap.height() > d->m_maxHeight ) )
   {
         /* We have to resize the pixmap to get it complete on the screen */
         QImage image=d->m_originalPixmap.toImage();
         d->m_originalPixmap=QPixmap::fromImage( image.scaled( width, height, Qt::KeepAspectRatio,Qt::SmoothTransformation ) );
         double oldZoomFactor = d->m_zoomFactor;
         d->m_zoomFactor=d->m_originalPixmap.width()/(double)d->m_unzoomedPixmap.width();

         if (d->m_selectedRegion.isValid())
         {
            d->m_selectedRegion=
                  QRect((int)(d->m_selectedRegion.x()*d->m_zoomFactor/oldZoomFactor),
                        (int)(d->m_selectedRegion.y()*d->m_zoomFactor/oldZoomFactor),
                        (int)(d->m_selectedRegion.width()*d->m_zoomFactor/oldZoomFactor),
                        (int)(d->m_selectedRegion.height()*d->m_zoomFactor/oldZoomFactor) );
         }
   }

   if (!d->m_selectedRegion.isValid()) d->m_selectedRegion = d->m_originalPixmap.rect();

   d->m_linedPixmap=QPixmap();
   d->updatePixmap();
   resize(d->m_label->width(), d->m_label->height());
}

#include "kpixmapregionselectorwidget.moc"
