// $Id: arrow.cpp 20164 2014-04-16 09:06:22Z hudson $
/**
 * This file is part of OpenModelica.
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 * Copyright (c) 1998-CurrentYear, Open Source Modelica Consortium (OSMC),
 * c/o Linköpings universitet, Department of Computer and Information Science,
 * SE-58183 Linköping, Sweden.
 *
 * All rights reserved.
 *
 * THIS PROGRAM IS PROVIDED UNDER THE TERMS OF GPL VERSION 3 LICENSE OR
 * THIS OSMC PUBLIC LICENSE (OSMC-PL).
 * ANY USE, REPRODUCTION OR DISTRIBUTION OF THIS PROGRAM CONSTITUTES RECIPIENT'S ACCEPTANCE
 * OF THE OSMC PUBLIC LICENSE OR THE GPL VERSION 3, ACCORDING TO RECIPIENTS CHOICE.
 *
 * The OpenModelica software and the Open Source Modelica
 * Consortium (OSMC) Public License (OSMC-PL) are obtained
 * from OSMC, either from the above address,
 * from the URLs: http://www.ida.liu.se/projects/OpenModelica or
 * http://www.openmodelica.org, and in the OpenModelica distribution.
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 * This program is distributed WITHOUT ANY WARRANTY; without
 * even the implied warranty of  MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE, EXCEPT AS EXPRESSLY SET FORTH
 * IN THE BY RECIPIENT SELECTED SUBSIDIARY LICENSE CONDITIONS OF OSMC-PL.
 *
 * See the full OSMC Public License conditions for more details.
 *
 * Main contributor 2010, Hubert Thierot, CEP - ARMINES (France)
 * Main contributor 2010, Hubert Thierot, CEP - ARMINES (France)

     @file arrow.cpp
     @brief Comments for file documentation.
     @author Hubert Thieriot, hubert.thieriot@mines-paristech.fr
     Company : CEP - ARMINES (France)
     http://www-cep.ensmp.fr/english/
     @version

/****************************************************************************
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 ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
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 ** This file is part of the examples of the Qt Toolkit.
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 #include <QtGui>

 #include "arrow.h"
 #include <math.h>

 const qreal Pi = 3.14;

 Arrow::Arrow(DiagramItem *startItem, DiagramItem *endItem,
          QGraphicsItem *parent, QGraphicsScene *scene)
     : QGraphicsLineItem(parent, scene)
 {
     myStartItem = startItem;
     myEndItem = endItem;
     setFlag(QGraphicsItem::ItemIsSelectable, true);
     myColor = Qt::black;
     setPen(QPen(myColor, 2, Qt::SolidLine, Qt::RoundCap, Qt::RoundJoin));
 }

 QRectF Arrow::boundingRect() const
 {
     qreal extra = (pen().width() + 20) / 2.0;

     return QRectF(line().p1(), QSizeF(line().p2().x() - line().p1().x(),
                                       line().p2().y() - line().p1().y()))
         .normalized()
         .adjusted(-extra, -extra, extra, extra);
 }

 QPainterPath Arrow::shape() const
 {
     QPainterPath path = QGraphicsLineItem::shape();
     path.addPolygon(arrowHead);
     return path;
 }

 void Arrow::updatePosition()
 {
     QLineF line(mapFromItem(myStartItem, 0, 0), mapFromItem(myEndItem, 0, 0));
     setLine(line);
 }

 void Arrow::paint(QPainter *painter, const QStyleOptionGraphicsItem *,
           QWidget *)
 {
     if (myStartItem->collidesWithItem(myEndItem))
         return;

     QPen myPen = pen();
     myPen.setColor(myColor);
     qreal arrowSize = 20;
     painter->setPen(myPen);
     painter->setBrush(myColor);

     QLineF centerLine(myStartItem->pos(), myEndItem->pos());
     QPolygonF endPolygon = myEndItem->polygon();
     QPointF p1 = endPolygon.first() + myEndItem->pos();
     QPointF p2;
     QPointF intersectPoint;
     QLineF polyLine;
     for (int i = 1; i < endPolygon.count(); ++i) {
     p2 = endPolygon.at(i) + myEndItem->pos();
     polyLine = QLineF(p1, p2);
     QLineF::IntersectType intersectType =
         polyLine.intersect(centerLine, &intersectPoint);
     if (intersectType == QLineF::BoundedIntersection)
         break;
         p1 = p2;
     }

     setLine(QLineF(intersectPoint, myStartItem->pos()));

     double angle = ::acos(line().dx() / line().length());
     if (line().dy() >= 0)
         angle = (Pi * 2) - angle;

         QPointF arrowP1 = line().p1() + QPointF(sin(angle + Pi / 3) * arrowSize,
                                         cos(angle + Pi / 3) * arrowSize);
         QPointF arrowP2 = line().p1() + QPointF(sin(angle + Pi - Pi / 3) * arrowSize,
                                         cos(angle + Pi - Pi / 3) * arrowSize);

         arrowHead.clear();
         arrowHead << line().p1() << arrowP1 << arrowP2;
         painter->drawLine(line());
         painter->drawPolygon(arrowHead);
         if (isSelected()) {
             painter->setPen(QPen(myColor, 1, Qt::DashLine));
         QLineF myLine = line();
         myLine.translate(0, 4.0);
         painter->drawLine(myLine);
         myLine.translate(0,-8.0);
         painter->drawLine(myLine);
     }
 }
