/*

* Copyright (c) 2008-2009 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:    Zoom Event Handler

*

*/

#ifndef GLXZOOMEVENTHANDLER_H_

#define GLXZOOMEVENTHANDLER_H_

#include "glxzoomview.hrh"

#include "glxfullscreenview.hrh"

#include "glxzoommathsengine.h"

//Alf Headers

#include <alf/alfevent.h>                   //  For Key Events

#include <alf/alftimedvalue.h>              // for TAlfRealPoint

#include <alf/alftypes.h>

#include <alf/alftypes.h>

#include <gesturehelper.h>

#include <gestureobserver.h>

// FORWARD DECLARATIONS

class CGlxZoomControl;

class TGlxZoomAndPanMathsEngine; 

class MGlxZoomEventHandlers;

class CGlxZoomPanEventHandler : public CBase

    {

public:

    /**

    * Two-phased constructor.

    * @param aZoomEventHandler: Handler for ZoomControl commands.

    */

    static CGlxZoomPanEventHandler* NewL(MGlxZoomEventHandlers& aZoomEventHandler );

    /**

    * Destructor.

    */

    ~CGlxZoomPanEventHandler();

    /**

    * Two stop shop to handle all alf events. [PRASH] Make this a one stop shop

    */     

    TBool HandleEventL(const TAlfEvent &aEvent );

    TBool HandleEvent( const TAlfEvent& aEvent );

    /**

    * Cancel the timer for continous zooming

    */     

    void CancelZoomPanTimer();

    void CancelAnimationTimer();

    /**

    * Stops the timer for showing the UI. 

    */ 

    void CancelUITimer();

    /*

     * ActivateZoom from the Zoom control

     */

                        TSize imageSize, 

                        TZoomStartMode aStartMode, 

                        TPoint* aZoomFocus);

    /*

     * DeactivateZoom from the Zoom control

     */

    void DeactivateZoom();

    /*

     * OrientationChanged

     */

    void OrientationChanged(const TRect& aNewScreenRect) ;

    /*

     * ZoomIsActivated

     * This is called when the zoom is activated/deactivated from Zoom control

     */

    void SetZoomActivated(TBool aIsActivated = EFalse);

    /*

     * ZoomUiState 

     * This is called when the zoom state in Zoom control is changed

     */

    void SetZoomUiState(TUiState aZoomUiState);

    /*

     * ZoomUiState 

     * This is called when the zoom state in Zoom control is changed

     */

    TUiState ZoomUiState();

    /**

    * Handle the drag events for panning

    */

    void HandleDragEvent(const GestureHelper::MGestureEvent& aEvent );

    /**

    * Handle the Pinch events for panning

    */

    void HandlePinchEventL(const GestureHelper::MGestureEvent& aEvent);

    /**

    * Handle the Double Tap events for panning

    */

    void HandleDoubleTap(const GestureHelper::MGestureEvent& aEvent );

    /**

    * Handle the Single Tap events for panning

    */

    void HandleSingleTap(const GestureHelper::MGestureEvent& aEvent );

    /**

    * Handle the Gesture Released events for panning

    */

    void HandleGestureReleased(const GestureHelper::MGestureEvent& aEvent );

    /**

    * Remembers the previous events code. 

    */

    void SetPreviousEventCode(const GestureHelper::TGestureCode code );

    /**

    * Handle a multitouch gesture released event.

    */

    void HandleMultiTouchReleased();

    /**

    * Bring back zoom state to minimum. 

    */

    void ZoomToMinimumL();

private:

    /*

     * Constructor

     */

    CGlxZoomPanEventHandler(MGlxZoomEventHandlers& aZoomEventHandler);

    /*

     * ConstructL

     */

    void ConstructL();

    /**

    *  This Function handles all the KeyEvents 

    */

    TBool HandlekeyEvents(const TAlfEvent &aEvent);

    /**

    * Callback function for pan

    */ 

    static TInt PanIntervalExpired(TAny* aPtr);

    // Zoom by the next zoom increment.

    // aZoomMode is ignored if aExpectedZoomLevel has a positive value

    void Zoom(TInt aExpectedZoomLevel, TInt aRelativeZoomFactor, TZoomMode aZoomMode = EZoomIn, TPoint* aZoomFocus = NULL);

    /**

    * Start Panning continously

    */     

    void DoPan();

    /**

    * Starts the timer for continous Panning

    */ 

    void StartPanTimer();

    /**

    * Starts the timer for showing the UI.

    */ 

    void StartUITimer(TTimeIntervalMicroSeconds32 aDelay,

            TTimeIntervalMicroSeconds32 anInterval,

            TCallBack aCallBack) ;

    /**

    *Call back function to Turn off UI/Screen Furniture[Back Key/Slider].

    */

    static TInt UiTimeOut(TAny* aSelf);

    /*

     * Timer callback for zoomout 

     */

    static TInt ZoomOutTimerL(TAny* aSelf);

    /**

    * Handle the key events for panning

    * @param aPanDirection: Specifies the pan direction

    * @param aEvent       : Specifies the event values.

    */

    TBool HandlePanKey(const TAlfEvent &aEvent);

    /**

    * Handle zoom key pressed.

    * @param aZoomIn    :ETrue for Zoom In key, EFalse for Zoom Out key

    * @param aEventCode :Type of key event.

    */

    void HandleZoomKey(TZoomMode aZoomMode ,TEventCode aEventCode);

    /**

    * Handle the drag events for panning

    */

    void HandleDragEvent(const TPoint &aTapPoint);

    /*

     * ShowSliderTillTimeout

     */

    void ShowSliderTillTimeout() ;

    /*

     * ShowScreenFurniture

     * aTimeout == 0 means no timeout.

     */

    void ShowScreenFurniture(TTimeIntervalMicroSeconds32 aTimeout);

    /*

     * HideScreenFurniture

     */

    void HideScreenFurniture();

    /*

     * SetupPanOperation

     */

    void SetupPanOperation(TPoint& aPanDirection);

    void CallZoomOutL();    

    void SetupAnimatedZoom(TZoomMode aZoomMode, TPoint * aZoomFocus = NULL);

    static TInt ActivationIntervalElapsed(TAny* aPtr) ;

    void NextStepAnimatedZoom();

    void SetupAnimatedPan() ; 

    static TInt PanInertiaFrameElapsed(TAny* aPtr);

    void NextStepInerticPan();

private:

    MGlxZoomEventHandlers&  iZoomEventHandler; 

    TTime               iPanTime;                       // The Purpose of this Variable is to determine the Time,for how long the key was held

    TZoomMode           iZoomMode;                      // Says whether we are zooming in or out.  

    TPoint              iPanDirection;                  // This gives the direction of the panning that has to be done

    TInt                iMinZoomRatio;                // The minimum value that the Zoom Slider will have  

    TInt                iMaxZoomRatio;                // The maximum value that the Zoom Slider will have

    CPeriodic*          iUiTimer;                       // The Timer used to Hide the UI/Screen Furniture[Back Key/Slider] after 2 seconds

    CPeriodic*          iZoomPanTimer;                  // The Timer used  for Zooming/Panning the Image Exponentially

    TPoint              iStartDisplayPoint;             // The variable holds the starting pointer posistion to determine the Drag Distance

    TTime               iDoubleTap;                     // This Variable is used to determine the double tap,by using the difference of the time 

                                                        // between subsequent single Tap.

    TInt                iZoomRatio;

    TRect               iDoubleTapRect;                 // This varaible holds the rect for the Double Tap

    TBool               iDragOngoing;                   // Is a drag event ongoing

    TBool               iZoomActivated;                 // To Denote if zoom is activated

    TUiState            iZoomUiState;                   // To Denote if the Ui is On in zoom

    TPoint              iPreviousPointerPosition;

    TPoint              iPreviousDragStartPosition;

    TBool               iIsZoomingInAnimatedState;

    TAnimationMode      iAnimatedZoomMode;

    CPeriodic*          iZoomAnimationTimer;

    TInt                iZoomPerInterval;

    TInt                iTargetAnimatedZoomRatio;

    TPoint              iZoomFocus;             

    GestureHelper::TGestureCode        iPreviousGestureCode ;

    TGlxZoomAndPanMathsEngine iMathsEngine;             

    };

#endif /* GLXZOOMEVENTHANDLER_H_ */