/*

* 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:    Layout that performs crossfade

 *

*/

//  Include Files

#include "shwzoomandpanlayout.h"

#include <e32math.h>

#include <uiacceltk/HuiCurvePath.h>

#include <glxlog.h>

#include "shwconstants.h"

#include "shwgeometryutilities.h"

using namespace NShwSlideshow;

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

// Constructor

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

TShwZoomAndPanLayout::TShwZoomAndPanLayout()

	: iScreenSize( 0, 0 ),

	iImageSize(	0, 0 ),

	iPanningCurve( NULL ) // T-class so need to set value

	{

	__DEBUG_ONLY( _iName = _L("TShwZoomAndPanLayout") );

	// default values

	// curve style is linear

	iCurvePosition.SetStyle( EAlfTimedValueStyleLinear );

	// set zoom style to sine so it accelerates and decelerates

	iZoomedSize.SetStyle( EAlfTimedValueStyleSineWave );

	}

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

// Destructor

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

TShwZoomAndPanLayout::~TShwZoomAndPanLayout()

	{

	// Do nothing

	}

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

// SetSizes

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

TReal32 TShwZoomAndPanLayout::SetSizes(

    TSize aScreenSize, TSize aImageSize, TSize aMaximumSize )

	{

	GLX_LOG_INFO( "TShwZoomAndPanLayout::SetSizes" );

	// set the size from TSize (integer) to THuiRealSize (float)

	iScreenSize.iWidth = aScreenSize.iWidth;

	iScreenSize.iHeight = aScreenSize.iHeight;

	iImageSize.iWidth = aImageSize.iWidth;

	iImageSize.iHeight = aImageSize.iHeight;

	// recalculate min and max size for zoom

	CalculateMinAndMaxSize( aMaximumSize );

	// calculate zoom factor for iHeight, iWidth is same as aspect ratio is kept

	// maximum per minimum

	TReal32 zoomFactor = iMaximumSize.iHeight / iMinimumSize.iHeight;

	// return zoom factor

	return zoomFactor;

	}

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

// SetPanningCurve

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

void TShwZoomAndPanLayout::SetPanningCurve( CAlfCurvePath* aCurve )

	{

	iPanningCurve = aCurve;

	}

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

// MaximumSize

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

TSize TShwZoomAndPanLayout::MaximumSize()

    {

    return iMaximumSize;

    }

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

// ResetSizeToMinimum

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

void TShwZoomAndPanLayout::ResetSizeToMinimum()

	{

	GLX_LOG_INFO( "TShwZoomAndPanLayout::ResetSizeToMinimum" );

	}

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

// StartZoom

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

void TShwZoomAndPanLayout::StartZoom(

	TZoomDirection aZoomDirection, TInt aDuration )

	{

	GLX_LOG_INFO1(

        "TShwZoomAndPanLayout::StartZoom( %d )", aDuration );

	// remember the zoom direction

	iZoomDirection = aZoomDirection;

	// remember also the zoom duration

	iZoomDuration = aDuration;

	// calculate curve position

	TInt curveLength = 0;

	// set curvelength, if we have curve

	if( iPanningCurve )

		{

		curveLength = iPanningCurve->Length();

		}

	// default case is to run the first half of the curve

	TInt curveStart = 0;

	TInt curveEnd = curveLength  / 2;

	// change the zoom according to direction

	if( EZoomOut == aZoomDirection )

		{

		GLX_LOG_INFO2( 

			"TShwZoomAndPanLayout:: Zooming out start(%.1f,%.1f)", 

			iMaximumSize.iWidth, iMaximumSize.iHeight );

		GLX_LOG_INFO2( 

			"TShwZoomAndPanLayout:: Zooming out target(%.1f,%.1f)", 

			iMinimumSize.iWidth, iMinimumSize.iHeight );

		// run the latter half of the curve

		curveStart = curveLength / 2;

		curveEnd = curveLength;

		}

	else // default case is EZoomIn

		{

		GLX_LOG_INFO2( 

			"TShwZoomAndPanLayout:: Zooming in start(%.1f,%.1f)", 

			iMinimumSize.iWidth, iMinimumSize.iHeight );

		GLX_LOG_INFO2( 

			"TShwZoomAndPanLayout:: Zooming in target(%.1f,%.1f)", 

			iMaximumSize.iWidth, iMaximumSize.iHeight );

		}

	// set position, if we have curve its either from start to half 

	// or half to end and if we dont then its always 0

	iCurvePosition.Set( curveStart );

	iCurvePosition.Set( curveEnd, aDuration );

	}

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

// Pause

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

TInt TShwZoomAndPanLayout::InvertZoom()

	{

	GLX_LOG_INFO( "TShwZoomAndPanLayout::InvertZoom" );

	if( EZoomOut == iZoomDirection )

		{

		StartZoom( EZoomIn, iZoomDuration );

		}

	else

		{

		StartZoom( EZoomOut, iZoomDuration );

		}

	return 0;

	}

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

// Pause

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

void TShwZoomAndPanLayout::Pause()

	{

	GLX_LOG_INFO( "TShwZoomAndPanLayout::Pause" );

	// pause size

	iZoomedSize.Pause();

	// pause curve position

	iCurvePosition.Pause();

	}

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

// Resume

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

void TShwZoomAndPanLayout::Resume()

	{

	GLX_LOG_INFO( "TShwZoomAndPanLayout::Resume" );

	// resume size

	iZoomedSize.Resume();

	// resume pan curve

	iCurvePosition.Resume();

	}

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

// DoSetLayoutValues

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

	{

	// calculate new x size, current value from zoomedsize

	TReal32 x_size = iZoomedSize.iWidth.Now();

	// calculate new y size, current value from zoomedsize

	TReal32 y_size = iZoomedSize.iHeight.Now();

	// ensure x is inside  maximum size and minimum size

    x_size = Min( x_size, iMaximumSize.iWidth );

    x_size = Max( x_size, iMinimumSize.iWidth );

    // ensure y is inside  maximum size and minimum size

    y_size = Min( y_size, iMaximumSize.iHeight );

    y_size = Max( y_size, iMinimumSize.iHeight );

	// set position only if we have a panning curve, this enables the use of this

    // layout as only a zooming layout and then some other layout can define 

    // the position (as we dont overwrite 0,0 there...)

	if( iPanningCurve )

		{

		// need to ensure that position does not make image 

		// go outside the bounding box. We trust that the curve has 

		// been calculated so that in 100% zoom it stays inside the image

		// so the only thing needed is to ensure zoom keeps the image inside

		// the box as well.

		// this is done by scaling the position with the current 

		// zoomfactor per maximum zoomfactor. The scalefactor is between

		// 0 and 1; when size is minimum the scale is 0 and when size

		// is maximum the scale is 1.

		// If we are in minimum size, we cant do any panning and

		// if we are in maximum size we can do the maximum pan.

		// current zoomfactor is current height per the minimum height

		// formula:

		//         current.y - minimum.y

		// scale = ---------------------

		//         maximum.y - minimum.y

		// and need to ensure maximum.y > minimum.y, otherwise scale becomes

		// infinite

		}

	}

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

// DoChanged

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

TBool TShwZoomAndPanLayout::DoChanged() const

	{

	TBool ret = EFalse;

	return iZoomedSize.Changed() || ret;

	}

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

// DoClearChanged

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

void TShwZoomAndPanLayout::DoClearChanged() 

	{

	iZoomedSize.ClearChanged();

	}

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

// CalculateMinAndMaxSize

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

void TShwZoomAndPanLayout::CalculateMinAndMaxSize( TSize aMaximumSize )

	{

    // use the namespace for coord utilities

    using namespace NShwGeometryUtilities;

    // set minimum size to be the image size

    iMinimumSize.iWidth = iImageSize.iWidth;

    iMinimumSize.iHeight = iImageSize.iHeight;

    // scale minimum size inside the screen

    FitToCoverBox( 

        iMinimumSize.iWidth, 

        iMinimumSize.iHeight, 

        iScreenSize.iWidth, 

        iScreenSize.iHeight );

    // check if the image is large enough for zooming

    TReal32 zoomFactor = 

        ( iImageSize.iWidth * iImageSize.iHeight ) / 

            ( iScreenSize.iWidth * iScreenSize.iHeight );

    // if combined zoom factor is big enough then zoom

    // so if image is for example half the width but double the height of screen

    // we dont zoom

    if( zoomFactor > KMinZoomAndPanFactor )

        {

        // the image should be zoomed, figure out if its

        // from screen size -> image size * KOptimalZoomAndPanFactor or

        // from screen size -> image size * KMaxZoomAndPanFactor

    	// set maximum size to image dimensions multiplied

    	// by KShwOptimalZoomAndPanFactor

    	// this defines how much we want the max zoom

    	// to be in optimal case

    	iMaximumSize.iWidth = iImageSize.iWidth * KOptimalZoomAndPanFactor;

    	iMaximumSize.iHeight = iImageSize.iHeight * KOptimalZoomAndPanFactor;

        // check if the image is large enough for zooming, 

        // only need to check either coordinate as aspect ratio is kept

        // Images between screen size and screen size * KMaxZoomAndPanFactor

    	// get zoomed between screen size and screen size * KMaxZoomAndPanFactor

        if( ( iMaximumSize.iWidth < iMinimumSize.iWidth * KMaxZoomAndPanFactor )||

            ( iMaximumSize.iHeight < iMinimumSize.iHeight * KMaxZoomAndPanFactor ) )

            {

            // image is too small from either dimension

            // so zoom from minimum size to Screen x KMaxZoomAndPanFactor

            FitToCoverBox( 

                iMaximumSize.iWidth, 

                iMaximumSize.iHeight,

                iScreenSize.iWidth * KMaxZoomAndPanFactor,

                iScreenSize.iHeight * KMaxZoomAndPanFactor );

            }

        // calculate maximum Width and Height for this image

        // the maximum thumbnailsize defines the maximum amount of pixels 

        // we should ever load. We need to adjust this box to have the

        // same aspect ratio of the image; so in short:

        //      same amount of pixels than maximum but aspect ratio of image

        TReal32 maxWidth = aMaximumSize.iWidth;

        TReal32 maxHeight = aMaximumSize.iHeight;

        // calculate the image size difference and take square root to get

        // multiplier for both width and height, ignore error

        //                    maximumWidth * maximumHeight

        // multiplier = sqrt( ---------------------------- )

        //                      imagewidth * imageheight 

        TReal64 multiplier;

        (void)Math::Sqrt( multiplier, 

            ( maxHeight * maxWidth ) / 

            ( iImageSize.iWidth * iImageSize.iHeight ) );

        // maxwidth = imagewidth * multiplier

        TReal32 maximumWidth = multiplier * iImageSize.iWidth;

        // maxheight = imageheight * multiplier

        TReal32 maximumHeight = multiplier * iImageSize.iHeight;

        // then fit the maximum size inside that box

        FitInsideBox( 

            iMaximumSize.iWidth, iMaximumSize.iHeight,

            maximumWidth, maximumHeight );

        }

    else

        {

        // not enough to zoom so just streth to screen size. 

        // set maximum to be minimum

        iMaximumSize.iWidth = iMinimumSize.iWidth;

        iMaximumSize.iHeight = iMinimumSize.iHeight;

        }

	}