/*

* Copyright (c) 2008-2009 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:    Common utility for thumbnail attributes

*

*/

// my include

#include "glxthumbnailutility.h"

// system includes

#include <glxtracer.h>

// user includes

#include "glxmedia.h"

#include "glxthumbnailattributeinfo.h"

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

// ClosestThumbnail

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

//

EXPORT_C /*static*/ TInt GlxThumbnailUtility::ClosestThumbnail(

        const TSize& aDesiredSize, const CGlxMedia& aMedia, TBool aDrmValid )

    {

    TRACER("GlxThumbnailUtility::ClosestThumbnail");

    TInt selectedIndex = KErrNotFound;

    TInt selectedQuality = 0;

    TSize selectedSize;     // Default constructor sets to zero

    TInt count = aMedia.Count();

    for ( TInt i = 0; i < count; i++ )

        {

        const TMPXAttribute& attr( aMedia.Attribute( i ) );

        // is it a thumbnail

        if ( GlxThumbnailUtility::IsFullThumbnail( attr ))

            {

            const CGlxThumbnailAttribute* thumbnail

                    = static_cast<const CGlxThumbnailAttribute*>(

                                                aMedia.ValueCObject( attr ) );

            if ( thumbnail )

                {

                // Check to see if this is to be the preferred attribute

                TBool preferThis = ETrue;

                TInt quality = thumbnail->iThumbnailQuality;

                TSize size( thumbnail->iDimensions );

                // Compare aspect ratios of required size and

                // this size to decide if using heights or widths

                if ( size.iHeight * aDesiredSize.iWidth

                        >= aDesiredSize.iHeight * size.iWidth )

                    {

                    // using heights

                    preferThis = PreferThisAttribute( size.iHeight,

                            selectedSize.iHeight, aDesiredSize.iHeight,

                            quality, selectedQuality, aDrmValid );

                    }

                else

                    {

                    // using widths

                    preferThis = PreferThisAttribute( size.iWidth,

                            selectedSize.iWidth, aDesiredSize.iWidth,

                            quality, selectedQuality, aDrmValid );

                    }

                if ( preferThis )

                    {

                    // Set this one as preferred so far

                    selectedIndex = i;

                    selectedQuality = quality;

                    selectedSize = size;

                    }

                }

            }

        }

    return selectedIndex;

    }

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

// IsFullThumbnail

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

//

EXPORT_C /*static*/ TBool GlxThumbnailUtility::IsFullThumbnail(const TMPXAttribute& aAttr)

	{

	TRACER("GlxThumbnailUtility::IsFullThumbnail");

	return ((KGlxMediaIdThumbnail == aAttr.ContentId()) 

    			&& GlxIsFullThumbnailAttribute(aAttr.AttributeId()));

	}

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

// PreferThisAttribute

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

//

/*static*/ TBool GlxThumbnailUtility::PreferThisAttribute(

                TInt aThisDimen, TInt aSelectedDimen, TInt aReqDimen,

                TInt aThisQuality, TInt aSelectedQuality, TBool aDrmValid )

    {

    TRACER("GlxThumbnailUtility::PreferThisAttribute");

    TBool preferThis = ETrue;

    if ( aThisDimen == aSelectedDimen )

        {

        // Only interested if better quality 

        preferThis = ( aThisQuality > aSelectedQuality );

        }

    else if ( aThisDimen < aReqDimen )

        {

        // Only interested if this one is larger than the selected one

        preferThis = ( aSelectedDimen < aThisDimen );

        }

    else if ( aThisDimen > aReqDimen )

        {

        // Only interested if the selected one is smaller than requested

        // or this one is smaller than the selected one

        preferThis = ( aDrmValid &&

            ( aSelectedDimen < aReqDimen || aThisDimen < aSelectedDimen ) );

        }

    else    // aThisDimen == aReqDimen

        {

        // The right size, so choose it

        }

    return preferThis;

    }