/*

* Copyright (c) 2004 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:  Attribute asynhronous data set hook.

*

*/

#ifndef CPENGATTRMODELASYNCDATASETHOOK_H

#define CPENGATTRMODELASYNCDATASETHOOK_H

//  INCLUDES

#include <E32Base.h>

//FORWARD DECLARATION

class CPEngPresenceAttrModel;

class MPEngPresenceAttrModelTypeImp;

// CLASS DECLARATION

/**

 * Attribute asynhronous data set hook.

 *

 * @since 3.0

 */

NONSHARABLE_CLASS( CPEngAttrModelAsyncDataSetHook ) : public CActive

    {

public: //Constructor and destructor

    /**

     * C++ default constructor.

     */

    CPEngAttrModelAsyncDataSetHook();

    /**

     * Destructor.

     * Cancels any outstanding request.

     */

    ~CPEngAttrModelAsyncDataSetHook();

public: // New functions

    /**

     * Initializess the hook.

     *

     * Sets the request status where to hook in

     * and also the attribute objects which to callback

     * when the request is completed or gets canceled.

     *

     * If hook is already active, leaves with KErrInUse.

     *

     * @since 3.0

     * @param aStatus The request status to hook in.

     * @param aAttributeModel The attribute model owning the hook.

     * @param aTypeImp The attribute model implementation

     * which data set to hook in.

     */

    void InitializeLC( TRequestStatus& aRequestStatus,

                       CPEngPresenceAttrModel& aAttributeModel,

                       MPEngPresenceAttrModelTypeImp& aTypeImp );

    /**

     * Gets the hooks own request status.

     *

     * This request status is given prior

     * starting the hook to concrete asynchronous

     * request.

     *

     * @since 3.0

     * @param The hook own request status.

     */

    TRequestStatus& Status();

    /**

     * Starts the data set hook.

     *

     * The hook must be properly initialized before a

     * call to start.

     *

     * Registered attribute object callbacks are called

     * when something happens in the hook.

     *

     * If the hook wasn't properly initialized before

     * starting, panics.

     *

     * @since 3.0

     */

    void Activate();

protected:  // Functions from CActive

    /**

     * Gets called when actual request completes.

     *

     * @since 3.0

     */

    void RunL();

    /**

     * Gets called when hook is cancelled.

     *

     * @since 3.0

     */

    void DoCancel();

protected:  // Helpers

    void Reset();

    static void ResetTheHook( TAny* aHook );

private:    // Data

    //REF: Attribute model (owner) to update after complete

    CPEngPresenceAttrModel*  iHookOwner;

    //REF: Attribute model implementation to cancel

    MPEngPresenceAttrModelTypeImp* iHookedImp;

    //REF: Request status to complete after hook operation

    TRequestStatus* iStatusToComplete;

    };

#endif      // CPENGATTRMODELASYNCDATASETHOOK_H

// End of File