/*

* Copyright (c) 2002 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:  

*      GMS picture viewer control - compatible with Editor Base.

*      It is based very much on the CMmsImageControl.

*

*/

#ifndef __GMSPICTURECONTROL_H_

#define __GMSPICTURECONTROL_H_

// INCLUDES

#include <MsgBaseControl.h>         // for CMsgBaseControl

// DATA TYPES

enum TGmsPicControlPanic

    {

    ENoParent,

    ENoImageFile,

    EBadImageContent,

    EConversionError,

    EScalingError,

    ENullPtr

    };

// FORWARD DECLARATIONS

class CImageDecoder;

class CFbsBitmap;

class CGmsAOCallBack;

class MIHLScaler;

// CLASS DECLARATION

/**

 * Message Editor Base compatible control for handling GMS pictures.

 */

class CGmsPictureControl : public CMsgBaseControl

{

public:  // Constructor and destructor

    /**

     * Two-phased constructor.

     * @param aParent parent control

     * @return new object

     */

    IMPORT_C static CGmsPictureControl* NewL(const CCoeControl* aParent);

    /**

     * Destructor.

     */

    IMPORT_C ~CGmsPictureControl();

public: // new functions

    /**

     * Loads the image into display.

     * After calling LoadImageL and adding image control to view using

     * iView->AddControlL call you must call imagecontrol->SizeChanged()

     * to make image appear in view.

     * @param aImageFile image file name - expected to be valid image

     * @param aMaxHeight maximum height of the displayed image - default is

     * 0 = {max display size or max thumbnail size}.

     */

    IMPORT_C void LoadImageL(

        const TFileName& aImageFile, TUint aMaxHeight = 0);

    /**

     * Gives the resolution of the original image read from a file.

     * @return Original image resolution

     */

    IMPORT_C TSize OriginalImageResolution() const;

public: // from CMsgBaseControl

    /**

     * Returns the current control rect.

     * @return Current control rect.

     */

    TRect CurrentLineRect();

    /**

     * Calculates and sets the size of the control and returns new size as

     * reference aSize.

     * @param aSize Reference to TSize which gives and gets the size.

     */

    void SetAndGetSizeL(TSize& aSize);

    /**

     * Handles clipboard operation.

     * @param aFunc The clipboard function.

     */

    void ClipboardL(TMsgClipboardFunc aFunc);

    /**

     * Handles editing operation.

     * @param aFunc The edit operation.

     */

    void EditL(TMsgEditFunc aFunc);

    /**

     * Checks if the focus change up or down is possible and

     * returns ETrue if it is.

     * @param aDirection The direction of focus change.

     * @return ETrue if focus change is possible.

     */

    TBool IsFocusChangePossible(TMsgFocusDirection aDirection) const;

    /**

     * Checks if the cursor location is on the topmost or downmost position

     * and returns ETrue if it is.

     * @param aLocation Topmost or bottom.

     * @return ETrue if cursor is in the specified part.

     */

    TBool IsCursorLocation(TMsgCursorLocation aLocation) const;

    /**

     * Returns edit permission flags.

     * @return Edit permission flags.

     */

    TUint32 EditPermission() const;

    /**

     * Resets (= clears) contents of the control.

     */

    void Reset();

    /**

     * Prepares control for viewing.

     * @param aEvent Event

     * @param aParam Parameter

     */

    void NotifyViewEvent(TMsgViewEvent aEvent, TInt aParam);

public: // TCallBack

   /**

    * TCallBack function for image conversion.

    * @param aPtr this class instance

    * @return always zero

    */

    static TInt ConversionReady( TAny* aPtr );

    static TInt ScalingReady( TAny* aPtr );

protected: // from CMsgBaseControl

    /**

     * Prepares for read only or non read only state.

     * @param aReadOnly Whether to prepare for read only or non-read only.

     */

    void PrepareForReadOnly(TBool aReadOnly);

protected: // from CCoeControl

    /**

     * CMsgBaseControl requires that this method is implemented.

     */

    TInt CountComponentControls() const;

    /**

     * CMsgBaseControl requires that this method is implemented.

     */

    CCoeControl* ComponentControl(TInt /*aIndex*/) const;

    /**

     * CMsgBaseControl requires that this method is implemented.

     */

    void FocusChanged( TDrawNow /*aDrawNow*/ );

    /**

     * Called when size is changed.

     */

    void SizeChanged();

    /**

     * Handles bitmap drawing.

     */

    void Draw(const TRect& aRect) const;

private: // New functions

   /**

    * Helper method which creates or rescales iScaledBitmap unless

    * image hasn't been loaded or conversion is currently ongoing.

    * @param aSize size for which to scale

    * @return ETrue if scaling was possible

    */

    TBool ScaleIfPossibleL( TSize aSize );

   /**

    * Callback method called when image conversion is ready.

    */

    void DoConversionReady();

   /**

    * Callback method called when image scaling is ready.

    */

    void DoScalingReady();

   /**

    * Panic wrapper.

    * @param aCode panic code

    */

    void Panic(TGmsPicControlPanic aCode);

    /**

     * Calculates the size for the image control.

     * NOTE: This method is old and used only if scalable layout IF is not available.

     * @param aProposedSize size given by the framework. Our size is either this or smaller.

     * @return new size for the control

     */

    TSize CalculateControlSize(TSize& aProposedSize);

    /**

     * Calculates the size for the image itself according to control rect.

     * NOTE: This method is old and used only if scalable layout IF is not available.

     * @return image size

     */

    TSize CalculateImageSize() const;

private: // Constructors

    /**

     * Second phase constructor.

     * @param aParent The parent.

     */

    void ConstructL(const CCoeControl* aParent);

   /**

    * Constructor

    */

    CGmsPictureControl();

private: //Data

    /// File server session

    RFs iFs;

    /// Maximum height.

    TUint iMaxHeight;

    /// Own: Image converter

    CImageDecoder* iConverter;

    /// Own: Active object which calls callback method when

    /// conversion has finished

    CGmsAOCallBack* iConversionAO;

    /// Own: Active object which calls callback method when

    /// scaling has finished

    CGmsAOCallBack* iScalingAO;

    /// Own: Bitmap, unscaled original

    CFbsBitmap* iBitmap;

    /// Own: Bitmap, scaled for current layout size

    CFbsBitmap* iScaledBitmap;

    /// Own: Bitmap scaler

    MIHLScaler* iScaler;

    /// Own: The rect of the bitmap

    TRect iBitmapRect;

};

#endif // __GMSPICTURECONTROL_H_

// end of file