/*

* Copyright (c) 2007-2008 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:    Thin callback wrapper

 *

*/

// include guard for the whole file content

#ifndef __SHWGEOMETRYUTILITIES_H__

#define __SHWGEOMETRYUTILITIES_H__

namespace NShwGeometryUtilities

    {

    /**

     * Utility to calculate the fitting for coordinates and maintaining the 

     * aspect ratio

     * @param aFitted reference to second coordinate, this value gets 

     *          multiplied with aNewAssigned / aAssigned

     * @param aAssigned reference to first coordinate, this value gets 

     *          assigned to aNewAssigned

     * @param aNewAssigned new value for first coordinate

     * 

     * Example: X coordinate needs to be assigned a new value X2 and you need

     * to calculate new Y coordinate maintaining the aspect ratio:

     * FitDimension( Y, X, X2 );

     * 

     * @author Kimmo Hoikka

     */

    template< typename T>

    void FitDimension( T& aFitted, T& aAssigned, T aNewAssigned )

        {

        // formula is:

        // aFitted = ( aFitted *  aNewAssigned ) / aAssigned

        // aAssigned = aNewAssigned

        // calculate second coordinate

        aFitted =

            ( aFitted * aNewAssigned ) /

                aAssigned;

        // assign the first coordinate

        aAssigned = aNewAssigned;

        }

    /**

     * Utility to fit width and height inside given box

     * maintaining the aspect ratio. Fit inside means that the image

     * does not fill the whole box and it is not stretched.

     * @param aWidth reference to the width to fit

     * @param aHeight reference to the height to fit

     * @param aBoxWidth the bounding box width

     * @param aBoxHeight the bounding box height

     */

    template< typename T>

    void FitInsideBox( T& aWidth, T& aHeight, T aBoxWidth, T aBoxHeight )

        {

        // calculate width difference

        T wdiff = aWidth - aBoxWidth;

        // calculate height difference

        T hdiff = aHeight - aBoxHeight;

        // check if wdiff is larger and positive

        if( ( wdiff > hdiff ) && wdiff > 0 )

            {

            // width is larger and too big for box so need to fit height

            FitDimension( aHeight, aWidth, aBoxWidth );

            }

        else if( hdiff > 0 )

            {

            // height is larger and too big for box so need to fit width

            FitDimension( aWidth, aHeight, aBoxHeight );

            }

        }

    /**

     * Utility to set width and height to cover given box

     * maintaining the aspect ratio. Fit cover means that the image

     * fills the whole box and some part of it does not fit inside the box.

     * @param aWidth reference to the width to fit

     * @param aHeight reference to the height to fit

     * @param aBoxWidth the bounding box width

     * @param aBoxHeight the bounding box height

     */

    template< typename T>

    void FitToCoverBox( T& aWidth, T& aHeight, T aBoxWidth, T aBoxHeight )

        {

        // try to fit with width first

        T newWidth = aWidth;

        T newHeight = aHeight;

        // calculate new height according to the width change

        FitDimension( newHeight, newWidth, aBoxWidth );

        // check if height is inside box

        if( newHeight < aBoxHeight )

            {

            // ok, it did not fill so fit according to height

            FitDimension( aWidth, aHeight, aBoxHeight );

            }

        else

            {

            // did fill the image so assign new values

            aWidth = newWidth;

            aHeight = newHeight;

            }

        }

    }

#endif // __SHWGEOMETRYUTILITIES_H__