/*

* 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:  Alf control group and control for capturing pointer events

*

*/

#include "pointercapturer.h"

#include <alf/alfcontrol.h>

#include <alf/alfcontrolgroup.h>

#include <alf/alfdisplay.h>

#include <alf/alfenv.h>

#include <alf/alfevent.h>

#include <alf/alfroster.h>

#include "gesturehelperimpl.h"

namespace GestureHelper

{

/**

 * CPointerCaptureControl

 * Gesture control own a gesture helper, and captures any pointer events that 

 * no other control captures. After it captures pointer down event, it will 

 * capture all pointer events until pointer up. It does this by bringing its

 * control group to the top upon pointer down, and lowering the control group

 * to the botton upon pointer up.

 */

NONSHARABLE_CLASS( CPointerCaptureControl ) : public CAlfControl

    {

public: 

    /** Two-phased constructor */

    static CPointerCaptureControl* NewLC( CGestureHelperImpl& aHelper, 

            CAlfEnv& aEnv, CAlfDisplay& aDisplay )

        {

        CPointerCaptureControl* self = new ( ELeave ) CPointerCaptureControl( aHelper );

        CleanupStack::PushL( self );

        self->ConstructL( aEnv ); // construct base class

        self->BindDisplay( aDisplay );

        self->AppendVisualL( EAlfVisualTypeVisual );       

        return self;

        }

    void StartCaptureL()

        {

        User::LeaveIfError( Display()->Roster().SetPointerEventObservers( 

            EAlfPointerEventReportDrag | EAlfPointerEventReportUnhandled, 

                *this ) );

        Display()->Roster().ShowL( *ControlGroup(), KAlfRosterShowAtTop );

        }

    void StopCapture()

        {

        ( void ) Display()->Roster().SetPointerEventObservers( 0, *this );

        TRAP_IGNORE( Display()->Roster().ShowL( *ControlGroup(), KAlfRosterShowAtBottom ) );

        }

private:

    /** Constructor */

    CPointerCaptureControl( CGestureHelperImpl& aHelper )

            : iHelper( aHelper )

        {

        }

    // From CAlfControl

    TBool OfferEventL( const TAlfEvent& aEvent )

        {

        TBool consumed = EFalse;

        if ( aEvent.IsPointerEvent() )

            {

            // pointer down for first pointer should never come here if everything is 

			// working properly. if pointer event comes here, stop capturing and allow the 

			// event to fall to the controls below

            if ( iHelper.StrayEvent(aEvent.PointerEvent() ))

                {

                StopCapture();

                }

            else 

                {

                consumed = iHelper.HandlePointerEventL( aEvent.PointerEvent() );

                }

            }

        return consumed;

        }

private:    

    /// gesture helper that analyses pointer sequences. own.

    CGestureHelperImpl& iHelper;

    };

} // namespace GestureHelper

using namespace GestureHelper;

// ----------------------------------------------------------------------------

// Two phase constructor

// ----------------------------------------------------------------------------

//

CPointerCapturer* CPointerCapturer::NewL()

    {

    return new ( ELeave ) CPointerCapturer();

    }

// ----------------------------------------------------------------------------

// Two phase constructor

// ----------------------------------------------------------------------------

//

CPointerCapturer::~CPointerCapturer()

    {

    if ( iCaptureControl )

        {

        // deleting the control group will also delete the control

        iCaptureControl->Env().DeleteControlGroup( iControlGroupId );

        }

    }

// ----------------------------------------------------------------------------

// InitForAlfredL

// ----------------------------------------------------------------------------

//

void CPointerCapturer::InitForAlfredL( CGestureHelperImpl& aHelper, 

        CAlfEnv& aEnv, CAlfDisplay& aDisplay, TInt aControlGroupId )

    {

    CAlfControlGroup& group = aEnv.NewControlGroupL( aControlGroupId );

    CPointerCaptureControl* control = CPointerCaptureControl::NewLC( aHelper, 

        aEnv, aDisplay );

    group.AppendL( control );

    CleanupStack::Pop( control );    

    // store control only after it has been successfully added to group

    iCaptureControl = control;

    iControlGroupId = aControlGroupId;

    }

// ----------------------------------------------------------------------------

// StartCaptureL

// ----------------------------------------------------------------------------

//

void CPointerCapturer::StartL()

    {

    if ( iCaptureControl )

        {

        iCaptureControl->StartCaptureL();

        }

    }

// ----------------------------------------------------------------------------

// StopCapture

// ----------------------------------------------------------------------------

//

void CPointerCapturer::Stop()

    {

    if ( iCaptureControl )

        {

        iCaptureControl->StopCapture();

        }

    }