/*

* Copyright (c) 2002-2008 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:  CCFContextOperation class implementation.

*

*/

// INCLUDES

#include <f32file.h> // for KExtDelimiter '.' and KDriveDelimiter ':'

#include "cfcontextoperation.h"

#include "cfbasicoptrace.h"

// CONSTANTS

const TInt KCFContextOperationNoContextLevelDelay = 0;

const TInt KDefaultPreviousValueLength = 256;

// ======== MEMBER FUNCTIONS ========

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

// CCFContextOperation::CCFContextOperation

// C++ default constructor can NOT contain any code, that might leave.

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

//

CCFContextOperation::CCFContextOperation( MCFOperationServices& aServices,

    CCFOperationNode* aParent,

    HBufC* aType,

    HBufC* aSource )

    :   CCFOperationNode( aServices, aParent ),

        iContextLevelDelay( 0 ),

        iSource( aSource ),

        iType( aType )

    {

    FUNC_LOG;

    iPreviousValue = HBufC::New( KDefaultPreviousValueLength );

    }

// Destructor

CCFContextOperation::~CCFContextOperation()

    {

    FUNC_LOG;

    delete iSource;

    delete iType;

    delete iPreviousValue;

    }

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

// CCFContextOperation::Evaluate

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

//

TBool CCFContextOperation::Evaluate( const CCFContextObject& aContext,

    TInt& aContextLevelDelay )

    {

    FUNC_LOG;

    DOM_INFO( "CCFContextOperation::Evaluate" );

    // Check that context value has changed (context is state information)

    if ( iPreviousValue && ( *iPreviousValue ).Compare( aContext.Value() ) == 0 )

        {

        INFO_2( "CCFContextOperation::Evaluate - NOT evaluating (prev value [%S] == arg value [%S])!",

            iPreviousValue, &aContext.Value() );

        aContextLevelDelay = KCFContextOperationNoContextLevelDelay;

        return EFalse;

        }

    TInt err = UpdatePreviousValue( aContext.Value() );

    ERROR( err, "Previous value update failed!" );

    // Ask concrete implementation if it is true

    TInt val( EFalse );

    TRAP( err, val = IsTrueL( aContext ) );

    if ( err != KErrNone )

        {

        ERROR( err, "CCFContextOperation: IsTrueL leave occurred, evaluation cancelled" );

        return EFalse;

        }

    // Evaluate parents if we have changed

    if ( val != iValue )

        {

        INFO_1( "CCFContextOperation::Evaluate - Value changed to (-1=undefined, 0=false, 1=true): %d", val );

        iValue = static_cast< TCFConditionValue >( val );

        if ( iParent )

            {

            iParent->Evaluate();

            }

        }

    else

        {

        INFO_1( "CCFContextOperation::Evaluate - Value still (-1=undefined, 0=false, 1=true): %d", val );

        }

    aContextLevelDelay = iContextLevelDelay;

    return ETrue;

    }

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

// CCFContextOperation::Source

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

//

TPtrC CCFContextOperation::Source() const

    {

    FUNC_LOG;

    return TPtrC( *iSource );

    }

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

// CCFContextOperation::Type

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

//

TPtrC CCFContextOperation::Type() const

    {

    FUNC_LOG;

    return TPtrC( *iType );

    }

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

// CCFContextOperation::IsAllRequired

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

//

TBool CCFContextOperation::IsAllRequired() const

    {

    FUNC_LOG;

    return EFalse;

    }

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

// CCFContextOperation::UpdatePreviousValue

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

//

TInt CCFContextOperation::UpdatePreviousValue( const TDesC& aNewValue )

    {

    FUNC_LOG;

    TInt err = KErrNone;

    if( !iPreviousValue )

        {

        iPreviousValue = HBufC::New( KDefaultPreviousValueLength );

        }

    if( iPreviousValue )

        {

        TPtr previousValuePtr = iPreviousValue->Des();

        if( previousValuePtr.MaxLength() >= aNewValue.Length() )

            {

            previousValuePtr.Copy( aNewValue );

            }

        else

            {

            delete iPreviousValue;

            iPreviousValue = NULL;

            iPreviousValue = aNewValue.Alloc();

            if( !iPreviousValue )

                {

                err = KErrNoMemory;

                }

            }

        }

    else

        {

        err = KErrNoMemory;

        }

    return err;

    }

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

// CCFContextOperation::PreviousValue

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

//

const TDesC& CCFContextOperation::PreviousValue()

    {

    if ( iPreviousValue )

        {

        return *iPreviousValue;

        }

    return KNullDesC;

    }

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

// CCFContextOperation::ActivateL

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

//

void CCFContextOperation::ActivateL()

    {

    FUNC_LOG;

    iServices.SubscribeContextL( this );

    }

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

// CCFContextOperation::Deactivate

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

//

void CCFContextOperation::Deactivate()

    {

    FUNC_LOG;

    iServices.RemoveSubscription( this );

    }

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

// CCFContextOperation::CheckSecurity

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

//

TInt CCFContextOperation::CheckSecurity()

    {

    FUNC_LOG;

    if ( !iSource || !iType )

        {

        return KErrBadDescriptor;

        }

    return iServices.CheckContextReadSecurity( *iSource, *iType );

    }

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

// CCFContextOperation::Evaluate

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

//

void CCFContextOperation::Evaluate()

    {

    FUNC_LOG;

    }