/*

* 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 zoom and fade

 *

*/

#ifndef __SHWZOOMANDPANLAYOUT_H__

#define __SHWZOOMANDPANLAYOUT_H__

#include <glxlayout.h>

//#include <alf/alfrealsize.h>

#include <alf/alftimedvalue.h>

#include <alf/alfcurvepath.h>

#include "shwtimedvalue.h"

// FORWARD DECLARATIONS

class CHuiCurvePath;

/**

 * TShwZoomAndPanLayout

 * Handles zooming and panning a visual

 * 

 * @author Kimmo Hoikka

 * @lib shwslideshowengine.lib

 * @internal reviewed 07/06/2007 by Loughlin

 * @internal reviewed 06/06/2007 by Dan Rhodes

 */

NONSHARABLE_CLASS( TShwZoomAndPanLayout ) : public TGlxLayout

	{

	public:

		/**

		 * Enumeration for zoom direction.

		 */

		enum TZoomDirection

			{

			EZoomIn = 1,	// Zoom in, from minimum to maximum size

			EZoomOut = 2	// Zoom out, from maximum to minimum size

			};

		/**

		 * Constructor, initializes the layout.

		 */

		TShwZoomAndPanLayout();

		/**

		 * Destructor

		 */

		~TShwZoomAndPanLayout();

		/**

		 * Sets the screen and image size

		 * @param aScreenSize the size of the screen.

		 * @param aImageSize the size of the image.

		 * @param aMaximumSize the maximum ever size for the image

		 * @return the zoom factor, this enables the client to deside 

		 *			if it makes sense to do any zoomimg

		 */

		TReal32 SetSizes( 

		    TSize aScreenSize, TSize aImageSize, TSize aMaximumSize );

		/**

		 * Sets the curve for pan. The curve must be defined so that in

		 * 100% zoom it stays inside the image (no black borders shown)

		 * basically this means a box inside image coordinates:

		 * xi = image.width/2;

		 * yi = image.height/2;

		 *

		 *  (-xi,yi)-------------(xi,yi)

		 *  |  (-xb,yb)-------(xb,yb)  |

		 *  |  |                    |  |

		 *  |  (-xb,-yb)-----(xb,-yb)  |

		 *  (-xi,-yi)-----------(xi,-yi)

		 *

		 * where:

		 *  xb = xi - screen.width/2;

		 *  yb = yi - screen.height/2;

		 *

		 * During zoom the panning curve is scaled according to current

		 * zoom factor so that no black borders show in zoom factors < 100%

		 *

		 * @param aCurve the curve to use for the panning.

		 */

		void SetPanningCurve( CAlfCurvePath* aCurve );

        /**

         * This method returns the maximum zoom size for the image

         * Should not be called before before SetSizes is called

         * @return the maximum size as TSize

         */

        TSize MaximumSize();

		/**

		 * This method resets the size to minimum. Usefull when you dont 

		 * want to do zoom & pan (for example the image is too small)

		 */

		void ResetSizeToMinimum();

		/**

		 * This method starts the zooming. If a pannig curve is used 

		 * it should be set before calling this method. Note, for zoom in

		 * the layout uses the first half of the curve and for zoom out

		 * the latter half; this enables you to use an ellipsis to have

		 * looping zoomin

		 *

		 * @param aZoomDirection the desired zoom direction

		 * @param aDuration the length of the zoom loop

		 */

		void StartZoom( TZoomDirection aZoomDirection, TInt aDuration );

		/** 

		 * This method inverts the zoom the opposite way

		 */

		TInt InvertZoom();

		/**

		 * This method pauses zoom and pan

		 */

		void Pause();

		/**

		 * This method resumes zoom and pan after pause.

		 */

		void Resume();

	protected:	// From TGlxLayout

		/// @ref TGlxLayout::DoSetLayoutValues

		void DoSetLayoutValues( TGlxLayoutInfo& aInfo );

		/// @ref TGlxLayout::DoChanged

		TBool DoChanged() const;

		/// @ref TGlxLayout::DoClearChanged

		void DoClearChanged();

	private:	// Data and private parts

		/// Helper to calculate minimum and maximum size

		void CalculateMinAndMaxSize( TSize aMaximumSize );

		/// Own: Screen size

		TAlfRealSize iScreenSize;

		/// Own: Image size

		TAlfRealSize iImageSize;

		/// Own: the maximum size

		TAlfRealSize iMaximumSize;

		/// Own: the minimum size

		TAlfRealSize iMinimumSize;

		/// Own: the zoom direction

		TZoomDirection iZoomDirection;

		/// Own: the zoom duration

		TInt iZoomDuration;

		/// Own: the zoomed size

		TShwTimedSize iZoomedSize;

		/// Own: Pan curve position

		TShwTimedValue iCurvePosition;

		/// Ref: Pan curve

		CAlfCurvePath* iPanningCurve;

	};

#endif // __SHWZOOMANDPANLAYOUT_H__