/*

* Copyright (c) 2006 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:   Thumbnail processor interface class

*

*/

#ifndef __TNEPROCESSOR_H__

#define __TNEPROCESSOR_H__

#include <e32base.h>

#include <e32std.h>

#include <gdi.h>

#include <TNECommon.h>

/*

 * Forward declarations.

 */

class CTNEProcessorImpl;

// @@ YHK Do we need this observer

// probably dont need it

class MTNEMovieProcessingObserver;

/**

 * Video processor.

 */

class CTNEProcessor : public CBase

	{

public:

	/** 

	 * Constructors for instantiating new video processors.

	 * Should reserve as little resources as possible at this point.

	 */

	static CTNEProcessor* NewL();

	static CTNEProcessor* NewLC();

	/** 

	 * Destructor can be called at any time (i.e., also in the middle of a processing operation).

	 * Should release all allocated resources, including releasing all allocated memory and 

	 * *deleting* all output files that are currently being processed but not yet completed.

	 */

	virtual ~CTNEProcessor();

    /**

	 * Read the header from the specified video clip file and return its properties.

	 * The file should be opened with EFileShareReadersOnly share mode.

	 *

	 * Possible leave codes:

	 *	- <code>KErrNoMemory</code> if memory allocation fails

	 *	- <code>KErrNotFound</code> if there is no file with the specified name

	 *    in the specified directory (but the directory exists)

	 *	- <code>KErrPathNotFound</code> if the specified directory

	 *    does not exist

	 *	- <code>KErrUnknown</code> if the specified file is of unknown format

	 *

	 * @param aFileHandle           file handle to read

	 * @param aVideoFormat          for returning the video format

	 * @param aVideoType            for returning the video type

	 * @param aResolution           for returning the resolution

	 * @param aVideoFrameCount      for returning the number of video frames

	 */

	void GetVideoClipPropertiesL(RFile& aFileHandle,

		                         TTNEVideoFormat& aFormat,

								 TTNEVideoType& aVideoType, 

								 TSize& aResolution,

								 TInt& aVideoFrameCount);

	/**

	 * Do all initializations necessary to start generating a thumbnail, e.g. open files, 

	 * allocate memory. The video clip file should be opened with EFileShareReadersOnly 

	 * share mode. The thumbnail should be scaled to the specified resolution and 

	 * converted to the specified display mode. If this method leaves, destructor should be called to free 

	 * allocated resources.

	 * 

	 * Possible leave codes:

	 *	- <code>KErrNoMemory</code> if memory allocation fails

	 *	- <code>KErrNotFound</code> if there is no file with the specified name

	 *    in the specified directory (but the directory exists)

	 *	- <code>KErrPathNotFound</code> if the specified directory

	 *    does not exist

	 *	- <code>KErrUnknown</code> if the specified file is of unknown format

	 *  - <code>KErrNotSupported</code> if the specified combination of parameters

	 *                                  is not supported

	 *

	 * @param aFileName  name of the file to generate thumbnail from

     * @param aIndex       Frame index for selecting the thumbnail frame

     *                     -1 means the best thumbnail is retrieved

 	 * @param aResolution  resolution of the desired thumbnail bitmap, or

	 *                     <code>NULL</code> if the thumbnail should be

	 *                     in the original resolution

	 * @param aDisplayMode desired display mode; or <code>ENone</code> if 

	 *                     any display mode is acceptable

	 * @param aEnhance	   apply image enhancement algorithms to improve

	 *                     thumbnail quality; note that this may considerably

	 *                     increase the processing time needed to prepare

	 *                     the thumbnail

	 */

	void StartThumbL(RFile& aFileHandle, TInt aIndex, TSize aResolution, 

					 TDisplayMode aDisplayMode, TBool aEnhance);	

     /**

	 * Starts thumbnail generation. Thumbnail generation is an asynchronous operation,

	 * and its completion is informed to the caller via Active object request completion;

	 * the iStatus member of the caller is passed as a parameter to this method.

	 *

	 * This method may leave if an error occurs in initiating the thumbnail generation.	

	 * If this method leaves, destructor should be called to free allocated resources.	

	 * 

	 * @param aStatus     Reference to caller's iStatus member variable

	 *

	 * @return  

	 *          

	 */

	void ProcessThumbL(TRequestStatus &aStatus);

	/** 

	 * Method for retrieving the completed thumbnail bitmap.

	 * 

	 * Video processor should not free the CFbsBitmap instance after it has passed it on 

	 * as a return value of this function 

	 *	 

	 */

	void FetchThumb(CFbsBitmap*& aThumb);

protected:

	CTNEProcessor();

	void ConstructL();

private:

	TInt iThumbProgress;

	CTNEProcessorImpl* iTNEProcessor;

	};

#endif // __TNEPROCESSOR_H__