/*

* Copyright (c) 2005-2007 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:  Modifier key status tracker for Active Idle WS Plug-in.

*

*/

#include "modifierkeytracker.h"

#include <e32keys.h>

#include <e32event.h>

//#define AI_ENABLE_RD_LOGGING

#define AI_RD_LOG_TO_DEBUG_OUTPUT

#include "debug.h"

namespace AiWsPlugin {

// LOCAL FUNCTIONS

TUint ModifierKeyToBit( TInt aScanCode )

    {

    switch( aScanCode )

        {

        case EStdKeyLeftShift:

            return EModifierLeftShift;

        case EStdKeyRightShift:

            return EModifierRightShift;

        case EStdKeyLeftAlt:

            return EModifierLeftAlt;

        case EStdKeyRightAlt:

            return EModifierRightAlt;

        case EStdKeyLeftCtrl:

            return EModifierLeftCtrl;

        case EStdKeyRightCtrl:

            return EModifierRightCtrl;

        case EStdKeyLeftFunc:

            return EModifierLeftFunc;

        case EStdKeyRightFunc:

            return EModifierRightFunc;

        default:

            return 0;

        }

    }

TUint UpdateCombinedIndicators(TUint aModifiers)

    {

    TUint result = aModifiers;

    struct TModifierCombinations { TUint iModifiers; TUint iCombinedIndicator; };

    static const TModifierCombinations KModifierCombinations[] =

        {

            { EModifierLeftShift | EModifierRightShift, EModifierShift },

            { EModifierLeftAlt   | EModifierRightAlt,   EModifierAlt   },

            { EModifierLeftCtrl  | EModifierRightCtrl,  EModifierCtrl  },

            { EModifierLeftFunc  | EModifierRightFunc,  EModifierFunc  }

        };

    const TModifierCombinations* KModifierCombinationsEnd = 

        KModifierCombinations + sizeof( KModifierCombinations ) / sizeof( KModifierCombinations[0] );

    for ( const TModifierCombinations* comb = KModifierCombinations;

          comb != KModifierCombinationsEnd;

          ++comb )

        {

        if ( aModifiers & comb->iModifiers )

            {

            result |= comb->iCombinedIndicator;

            }

        else

            {

            result &= ~comb->iCombinedIndicator;

            }

        }

    return result;

    }

// MEMBER FUNCTIONS

TModifierKeyTracker::TModifierKeyTracker() :

    iModifiers( 0 )

    {

    }

TBool TModifierKeyTracker::Update(const TRawEvent& aRawEvent)

    {

    TUint modifiers = iModifiers;

    switch( aRawEvent.Type() )

        {

        case TRawEvent::EKeyDown:

            {

            modifiers |= ModifierKeyToBit( aRawEvent.ScanCode() );

            modifiers = UpdateCombinedIndicators( modifiers );

            break;

            }

        case TRawEvent::EKeyUp:

            {

            modifiers &= ~ModifierKeyToBit( aRawEvent.ScanCode() );

            modifiers = UpdateCombinedIndicators( modifiers );

            break;

            }

        // DEBUG: Compare to what modifer update event would report

        case TRawEvent::EUpdateModifiers:

            {

            __PRINT( 

                __DBG_FORMAT("AiWsPlugin: TModifierKeyTracker::Update(), iModifers=%d, TRawEvent::Modifiers()=%d"), 

                iModifiers, aRawEvent.Modifiers() );

            break;

            }

        default:

            {

            // No operations..

            break;

            }

        }

    if( modifiers != iModifiers )

        {

        iModifiers = modifiers;

        return ETrue;

        }

    else

        {

        return EFalse;

        }

    }

} // namespace AiWsPlugin