/*

* 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:    The effect interface

 *

*/

#ifndef __SHWEFFECT_H__

#define __SHWEFFECT_H__

// INCLUDES

#include <e32std.h>

#include <e32base.h>

#include <alf/alfvisual.h>

#include <alf/alfenv.h>

#include "shweffectinfo.h"

// FORWARD DECLARATIONS

class MGlxVisualList;

class MGlxMediaList;

class CAlfEnv;

class MGlxLayout;

class CAlfVisual;

class TShwEffectInfo;

// CLASS DECLARATION

/**

 * MShwEffect, interface for the effects.

 * Effect gets the visual and media list and the HUI environment in 

 * initialisation as well as the screen size.

 */

class MShwEffect

	{

	public: // Construction & destruction

		/**

		 * Destructor. Allow deletion through this interface

		 */

		virtual ~MShwEffect() {};

		/**

		 * Clone the effect, this is needed when same effect

		 * is used multiple times in a row.

		 * @return a clone of the effect.

		 */

		virtual MShwEffect* CloneLC() = 0;

	public: // the API

		/**

		 * Initialize the effect.

		 * @param aHuiEnv, the HUI environment for the slideshow

		 * @param aVisualList, the visual list used for the slideshow

		 * @param aMediaList, the media list used for the slideshow

		 * @param aScreenSize, the screen size for the slideshow

		 */

		virtual void InitializeL( 

    		CAlfEnv* aAlfEnv,

		    MGlxVisualList* aVisualList,

		    MGlxMediaList* aMediaList,

		    TSize aScreenSize ) = 0;

		/**

		 * This method is called before the view mode of the effect for

		 * the given visual is about to start

		 * @param aVisual the HUI visual that is the target for the effect

		 * @param aSize the size of the image to view

		 * @param the size of the thumbnail to load for the effect

		 */

		virtual TSize PrepareViewL(

			CAlfVisual* aVisual, TSize aImageSize ) = 0;

		/**

		 * Enter view mode. The effect may fade-in itself,

		 * the duration for this is given as a parameter.

		 * @param aVisual the HUI visual that is the target for the view

		 * @param aDuration the whole view mode time

		 * @param aFadeInDuration the entry "fade-in" time

		 * @return the layout chain that applies for the view mode

		 */

		virtual MGlxLayout* EnterViewL( 

			CAlfVisual* aVisual, TInt aDuration, TInt aFadeInDuration ) = 0;

		/**

		 * Exit view mode. This gets called just before the transition 

		 * phase starts.

		 * @param aVisual the HUI visual that was the target for the view

		 */

		virtual void ExitView( CAlfVisual* aVisual ) = 0;

		/**

		 * Enter transition mode. The duration for the transition is given

		 * as a parameter, during this time the effect can animate its exit.

		 * @param aVisual the HUI visual that is the target for the transition

		 * @param aDuration the length of the transition

		 * @return the layout chain that applies for the transition mode

		 */

		virtual MGlxLayout* EnterTransitionL(

			CAlfVisual* aVisual, TInt aDuration ) = 0;

		/**

		 * Exit from transition mode. This method is called once the transition 

		 * has ended and the corresponding visual is no longer visible on screen.

		 * @param aVisual the HUI visual that was the target for the transition

		 */

		virtual void ExitTransition( CAlfVisual* aVisual ) = 0;

		/**

		 * Go to pause. While on pause the effect is expected to be frozen

		 */

		virtual void PauseL() = 0;

		/**

		 * Resume from pause.

		 */

		virtual void Resume() = 0;

        /**

         * Encapsulates the effect's display name and uid

         * @return the effect's information

         */

        virtual TShwEffectInfo EffectInfo() = 0;

	};

#endif // __SHWEFFECT_H__