/*

* Copyright (c) 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:  Downscales images when necessary

 *

*/

#ifndef CPIMIMAGESCALER_H

#define CPIMIMAGESCALER_H

//  INCLUDES

#include <e32base.h>

#include <imageconversion.h>

#include <bitmaptransforms.h>

// CONSTANTS

const TInt KThumbHeight = 96;

const TInt KThumbWidth = 80;

const TInt KMaxJpegSize = 23296; // 80*96*3+256

// CLASS DECLARATION

/**

 *  Scales bitmaps when necessary.

 *  The purpose of this class is to resize given bitmaps to thumbnail size

 * (80x96). If the given image is already smaller than 80x96, it is not scaled.

 *

 */

NONSHARABLE_CLASS(CPIMImageScaler): public CActive

{

public: // type definitions

    enum TState

    {

        EReady,

        EOpening,

        EScaling,

        EEncoding,

        ECompleted,

        // Error state

        EError

    };

public: // Constructors and destructor

    /**

     * Two-phased constructor.

     */

    static CPIMImageScaler* NewL();

    /**

     * Destructor.

     */

    virtual ~CPIMImageScaler();

public: // New functions

    /**

     * Scales the bitmap to thumbnail size (80x96) if necessary.

     * The image is not scaled, if it already is smaller than necessary.

     *

     * @param aSrcImage Source image.

     * @return thumbnail sized full color JPEG as a descriptor. Caller takes

     * the ownership.

     */

    HBufC8* ScaleL(TDesC8& aSrcImage);

public: // CActive

    void RunL();

    void DoCancel();

private:

    /**

     * C++ default constructor.

     */

    CPIMImageScaler();

    /**

     * Second phase constructor

     */

    void ConstructL();

    /**

     * Completes the operation

     * @param aError Error status or KErrNone if no error

     */

    void Complete(TInt aError);

    /**

     * Checks the given size. If the size is larger than required,

     * returns true

     */

    TBool CheckSize(TSize aSize);

    /**

     * Encodes the image

     */

    void Encode();

private: // Data

    // Opens JPEG images from a descriptor, owned

    CImageDecoder* iImageReader;

    // Converts bitmap to a JPEG image, owned

    CImageEncoder* iImageWriter;

    // Scales bitmaps,owned

    CBitmapScaler* iBitmapScaler;

    // Holds the encoded image. Owned while processing the image

    // when the image is returned, this pointer is changed to NULL.

    HBufC8* iImage;

    // Holds the bitmap. Owned.

    CFbsBitmap* iBitmap;

    // Waits for the operation to complete. Owned.

    CActiveSchedulerWait* iWait;

    // Current state

    TState iState;

    // Error code, propagated upwards on error

    TInt iError;

    // Do we have a connection to Font and Bitmap Server

    TBool iFbsSessionConnected;

    RFs iFileServer;

};

#endif // CPIMIMAGESCALER_H

// End of File