/*

* Copyright (c) 2010 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description: 

*

*/

#include <assert.h>

#include "graphicsitemflipper.h"

#include "utilities.h"

GraphicsItemFlipper::GraphicsItemFlipper(QGraphicsItem *parentItem, QGraphicsScene *scene, int duration,

                                         uint updateInterval, int zValue)

  : m_timeLine(duration)

{

    m_timeLine.setUpdateInterval(updateInterval);

    m_timeLine.setCurveShape(QTimeLine::EaseInOutCurve);

    safe_connect(&m_timeLine, SIGNAL(valueChanged(qreal)), this, SLOT(updateFlipStep(qreal)));

    safe_connect(&m_timeLine, SIGNAL(finished()), this, SLOT(onFinished()));

    m_pixmapItem = new QGraphicsPixmapItem(parentItem);

    scene->addItem(m_pixmapItem);

    m_pixmapItem->setZValue(zValue);

}

GraphicsItemFlipper::~GraphicsItemFlipper()

{

    delete m_pixmapItem;

    if(m_sourcePixmap) delete m_sourcePixmap;

    if(m_targetPixmap) delete m_targetPixmap;

}

void GraphicsItemFlipper::start(QGraphicsView *view, QGraphicsWidget *sourceWidget, QGraphicsWidget *targetWidget,

                                bool forward)

{

    emit starting();

    getPixmaps(view, sourceWidget, targetWidget);

    m_pixmapItem->setPixmap(forward ? *m_sourcePixmap : *m_targetPixmap);

    m_pixmapItem->show();

    m_timeLine.setDirection(forward ? QTimeLine::Forward : QTimeLine::Backward);

    m_timeLine.start();

}

void GraphicsItemFlipper::getPixmaps(QGraphicsView *view, QGraphicsWidget *sourceWidget, QGraphicsWidget *targetWidget)

{

    Q_UNUSED(view)

    QStyleOptionGraphicsItem options;

    m_sourceRect = sourceWidget->geometry();

    m_targetRect = targetWidget->geometry();

    // Get a snapshot of the source widget.

    m_sourcePixmap = new QPixmap(m_sourceRect.size().toSize());

    QPainter painter(m_sourcePixmap);

    options.exposedRect = m_sourceRect;

    sourceWidget->paint(&painter, &options);

    painter.end();

    // Get a snapshot of the target widget and flip it left to right.

    QPixmap tmpPixmap(m_targetRect.size().toSize());

    QPainter targetPainter(&tmpPixmap);

    options.exposedRect = m_targetRect;

    targetWidget->paint(&targetPainter, &options);

    targetPainter.end();

    m_targetPixmap = new QPixmap(tmpPixmap.transformed(QTransform().rotate(180, Qt::YAxis)));

}

void GraphicsItemFlipper::updateFlipStep(qreal value)  // slot

{

    //qreal scale = 1 - sin(3.14 * value) * 0.5;

    qreal sourceW = m_sourceRect.width();

    qreal sourceH = m_sourceRect.height();

    qreal deltaW = m_targetRect.width() - sourceW;

    qreal deltaH = m_targetRect.height() - sourceH;

    qreal deltaX = m_targetRect.left() - m_sourceRect.left();

    qreal deltaY = m_targetRect.top() - m_sourceRect.top();

    qreal xScale = (sourceW + (deltaW * value))/sourceW;

    qreal yScale = (sourceH + (deltaH * value))/sourceH;

    qreal newW = sourceW * xScale;

    qreal newH = sourceH * yScale;

    qreal dx = m_pixmapItem->pos().x() + (deltaX * value) + (newW/2);

//    qDebug() << "GraphicsItemFlipper::updateFlipStep: value=" << value;

//            << " xScale=" << xScale

//            << " newW=" << newW

//            << " deltaX=" << deltaX;

    // Set the appropriate pixmap.  If we've gone past the halfway point, ie. the item is edge-on,

    // switch pixmaps.

    // To do: Only set the pixmap twice, once when the animation starts and once at the halfway

    //        point.  Need to be sure resolution is correct at the end of the animation.

    if(value > 0.5) {

        m_pixmapItem->setPixmap(m_targetPixmap->scaled(int(newW), int(newH)));

    }

    else {

        m_pixmapItem->setPixmap(m_sourcePixmap->scaled(int(newW), int(newH)));

    }

    QTransform transform;

    transform.translate(dx, 0);

    transform.rotate(180 * value, Qt::YAxis);

    transform.translate(-dx, 0);

    transform.translate(deltaX * value, deltaY * value);

    m_pixmapItem->setTransform(transform);

}

void GraphicsItemFlipper::onFinished()

{

    m_pixmapItem->hide();

    emit finished();

}