/*

 * Copyright (c) 2009 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: Customized scroll area which handles dynamic slide loading in

 *              unifiedviewer

 *

 */

#include "uniscrollarea.h"

#include <HbScrollBar>

//---------------------------------------------------------------

//UniScrollArea :: UniScrollArea

// @see header file

//---------------------------------------------------------------

UniScrollArea::UniScrollArea(QGraphicsItem * parent) :

    HbScrollArea(parent), mCurrentSlide(0), mTotalSlides(0)

{

    bool flag = connect(this, SIGNAL(scrollingEnded()),

    this, SLOT(handleScrollingEnded()));

    bool flag1 = connect(this, SIGNAL(scrollingStarted()),

    this, SLOT(handleScrollingStarted()));

}

//---------------------------------------------------------------

//UniScrollArea :: ~UniScrollArea

// @see header file

//---------------------------------------------------------------

UniScrollArea::~UniScrollArea()

{

}

//---------------------------------------------------------------

//UniScrollArea :: setTotalSlides

// @see header file

//---------------------------------------------------------------

void UniScrollArea::setTotalSlides(int totalSlides)

{

    mTotalSlides = totalSlides;

}

//---------------------------------------------------------------

//UniScrollArea :: resetCurrentSlide

// @see header file

//---------------------------------------------------------------

void UniScrollArea::resetCurrentSlide()

{

    mCurrentSlide = 0;

}

//---------------------------------------------------------------

//UniScrollArea :: handleScrollingEnded

// @see header file

//---------------------------------------------------------------

void UniScrollArea::handleScrollingEnded()

{

    // TODO : reduce the complexity , code readability

    // TODO : avoid calculating the heights every time

    int currentSlide = -1;

    QList<qreal> heights;

    heights.clear();

    // contents() is not available so replaced with contentWidget()

    //    mScrollEndPoint = this->contents()->pos();

    mScrollEndPoint = this->contentWidget()->pos();

    // contents() is not available so replaced with contentWidget()

    QList<QGraphicsItem *> list = this->contentWidget()->childItems();

    for (int i = 0; i < list.size(); i++)

    {

        QRectF rect = list[i]->boundingRect();

        heights.append(- (rect.height()));

    }

    qreal h = 0.0;

    for (int i = 0; i < heights.size(); i++)

    {

        h += heights.at(i);

        if (mScrollEndPoint.y() > h)

        {

            currentSlide = i;

            break;

        }

    }

    if (mScrollEndPoint.y() < mScrollStartPoint.y())

    {

        //Identify if we are in last slide / last but one slide as we always

        // assume the slide next to current slide is always loaded

        //(Assumtion is based on slide initial load count of 2)

        if (currentSlide >= mTotalSlides - 1)

        {

            return;

        }

        //(This can be removed and emit signal if we cross 50% of last slide)

        if (currentSlide >= mTotalSlides - 2)

        {

            return;

        }

        //Determine how much we have scrolled & if we have scrolled beyond 50%

        //of current slide load the slide next to next slide

        qreal delta = heights.at(currentSlide) / 2;

        qreal fh = h - delta;

        if (mScrollEndPoint.y() < fh)

        {

            emit scrolledToNextSlide();

        }

    }

}

//---------------------------------------------------------------

//UniScrollArea :: handleScrollingStarted

// @see header file

//---------------------------------------------------------------

void UniScrollArea::handleScrollingStarted()

{

    // contents() is not available so replaced with contentWidget()

    //   mScrollStartPoint = this->contents()->pos();

    mScrollStartPoint = this->contentWidget()->pos();

}

//---------------------------------------------------------------

//UniScrollArea :: setPosToStart

// @see header file

//---------------------------------------------------------------

void UniScrollArea::setPosToStart()

{

    // contents() is not available so replaced with contentWidget()

    QGraphicsItem* widgetItem = this->contentWidget();

    widgetItem->setPos(0, 0);

}

// EOF