/*

* Copyright (c) 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:  Pinch touch gesture recognizer.

*

*/

#ifndef C_AKNTOUCHGESTUREFWPINCHRECOGNIZER_H

#define C_AKNTOUCHGESTUREFWPINCHRECOGNIZER_H

#include "akntouchgesturefwbaserecognizer.h"

namespace AknTouchGestureFw {

/**

 *  Pinch touch gesture recognizer.

 *

 *  @lib akntouchgesturefw

 *  @since S60 v5.2

 */

NONSHARABLE_CLASS( CAknTouchGestureFwPinchRecognizer )

    : public CAknTouchGestureFwBaseRecognizer

    {

public:

    /**

     * Two-phased constructor.

     *

     * @param  aEngine  The gesture recognition engine.

     */ 

    static CAknTouchGestureFwPinchRecognizer* NewL(

            CAknTouchGestureFwRecognitionEngine& aEngine );

    /**

     * Two-phased constructor.

     *

     * @param  aEngine  The gesture recognition engine.

     */

    static CAknTouchGestureFwPinchRecognizer* NewLC(

            CAknTouchGestureFwRecognitionEngine& aEngine );

    /**

     * Destructor.

     */

    virtual ~CAknTouchGestureFwPinchRecognizer();

public: // From base class CAknTouchGestureFwBaseRecognizer.

    /**

     * Returns the recognizer gesture group.

     * 

     * @return @c EAknTouchGestureFwGroupPinch

     */

    TAknTouchGestureFwGroup GestureGroup() const;

    /**

     * Cancels the gesture recognition.

     */

    void CancelRecognizing();

    /**

     * Handles single pointer event.

     * 

     * @param  aPointerData  Pointer event related data.

     */

    void HandleSinglePointerEventL( const TPointerEventData& aPointerData );

    /**

     * Handles multi pointer event.

     *

     * @param  aPointerData            Pointer event related data.

     * @param  aFirstPointerPosition   First pointer position.

     * @param  aSecondPointerPosition  Second pointer position.

     */

    void HandleMultiPointerEventL( const TPointerEventData& aPointerData,

                                   const TPoint& aFirstPointerPosition,

                                   const TPoint& aSecondPointerPosition );

private:

    /**

     * C++ constructor.

     *

     * @param  aEngine  The gesture recognition engine.

     */

    CAknTouchGestureFwPinchRecognizer(

            CAknTouchGestureFwRecognitionEngine& aEngine );

    /**

     * Resets recognizer's state.

     */

    void Reset();

    /**

     * Starts multi-touch recognition.

     *

     * @param  aFirstPointerPos   Position of first pointer.

     * @param  aSecondPointerPos  Position of second pointer.

     */

    void StartMultiRecognizing(

            const TPoint& aFirstPointerPos,

            const TPoint& aSecondPointerPos );

    /**

     * Handles multi-touch recognition cycle.

     * Called for every drag event when one pointer is down. 

     *

     * @param aEventTime Time of pointer event.

     * @param  aFirstPointerPos   New position of first pointer.

     * @param  aSecondPointerPos  New position of second pointer.

     */

    void MultiRecognizeL(

            const TTime& aEventTime,

            const TPoint& aFirstPointerPos,

            const TPoint& aSecondPointerPos );

    /**

     * Completes multi touch recognition.

     * 

     * @param aEventTime Time of pointer event.

     */

    void CompleteMultiRecognizingL(

            const TTime& aEventTime );

    /**

     * Asks engine to send pinch event to observer.

     * 

     * @param aGestureState  Pinch gesture state.

     * @param aMovementDelta delta movement.

     */

    void SendPinchEventL( 

            TAknTouchGestureFwState aGestureState, 

            TInt aMovementDelta );

    /**

     * Returns pinch initial threshold.

     *

     * @return Pinch initial threshold.

     */

    TInt PinchInitialThreshold() const;

    /**

     * Returns pinch movement threshold.

     *

     * @return Pinch movement threshold.

     */

    TInt PinchMovementThreshold() const;

    /**

     * Returns pinch direction change sensitivity.

     * 

     * @return pinch direction change sensitivity.

     */

    TInt PinchDirectionChangeSensitivity() const;

    /**

     * Returns pinch direction reset sensitivity.

     *

     * @return pinch direction reset sensitivity.

     */

    TInt PinchDirectionResetSensitivity() const;

    /**

     * Returns pinch dimension threshold.

     * 

     * @return pinch dimension threshold.

     */

    TInt PinchDimensionThreshold() const;

    /**

     * Returns pinch maximum confirmation duration.

     * 

     * @return pinch maximum confirmation duration.

     */

    TInt PinchMaximumConfirmationDuration() const;

    /**

     * Calculates bounding rect so that both aPoint1 and aPoint2 are inside

     * the rectangle.

     *

     * @param aPoint1 First position.

     * @param aPoint2 Second position.

     * @return Bounding rect.

     */

    static TRect CalculateBoundingRect( 

            const TPoint& aPoint1, 

            const TPoint& aPoint2 );

    /**

     * Snaps aValue to aReference if they are sufficiently close 

     * (defined by aMargin).

     *

     * @param aValue Value to be checked.

     * @param aReference Reference value.

     * @param aMargin Margin (applied to all directions).

     */

    static void NormalizeValue( TInt& aValue, TInt aReference, TInt aMargin );

    /**

     * Calculates movement value from width & height delta.

     * 

     * @param aWidthDelta Width delta.

     * @param aHeightDelta Height delta.

     * @return movement value, 0 if no movement.

     */

    static TInt CalculateMovement( TInt aWidthDelta, TInt aHeightDelta );

    /**

     * Checks duration threshold.

     * @param aEventTime Current pointer event time.

     * @return ETrue if ok, EFalse otherwise.

     */

    TBool CheckDurationThreshold( const TTime& aEventTime ) const;

private: // data

    /**

     * Boolean flag to indicate whether pinch gesture has been detected.

     */

    TBool iPinchDetected;

    /**

     * Current bounding rectangle for pinch.

     */

	TRect iPinchRect;

	/**

	 * Direction tracer for width.

	 */

	TDirectionTracer iPinchWidthTracer;

	/**

	 * Direction tracer for height.

	 */

	TDirectionTracer iPinchHeightTracer;

    /**

     * Pinch width direction tracer reset counter.

     * If height changes repeatedly without any width changes,

     * then width direction tracer is reset.

     */

	TInt iResetPinchWidthTracer;

	/**

	 * Pinch height direction tracer reset counter.

	 * If width changes repeatedly without any height changes,

	 * then height direction tracer is reset.

	 */

	TInt iResetPinchHeightTracer;

	/**

	 * Time (from event) when iStoredWidthDelta & iStoredHeightDelta

	 * were updated.

	 */

	TTime iStoredTime;

	/**

	 * Stored width delta value.

	 */

	TInt iStoredWidthDelta;

	/**

	 * Stored height delta value.

	 */

	TInt iStoredHeightDelta;

	/**

	 * ETrue if continuous feedback ongoing.

	 */

	TBool iContinuousFeedback;

    };

} // namespace AknTouchGestureFw

#endif // C_AKNTOUCHGESTUREFWPINCHRECOGNIZER_H