/*

* Copyright (c) 2010 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:  Active object helper class.

*

*/

#ifndef BTSIMPLEACTIVE_H

#define BTSIMPLEACTIVE_H

#include <e32base.h>

class CBtSimpleActive;

/**

 * APIs from this class offer functionalities that are common in mw and app 

 * components of Bluetooth packages. They do not serve as domain APIs.

 * 

 * Using these from external components is risky, due to possible source

 * and binary breaks in future.

 * 

 */

/**

 *  Class MBtSimpleActiveObserver

 *

 *  Callback class for receiving a completed active object event.

 *  Users of CBtSimpleActive need to derive from this class. 

 *

 *  @lib bteng*.lib

 *  @since S60 v3.2

 */

class MBtSimpleActiveObserver

    {

public:

    /**

     * Callback from RunL() to notify that an outstanding request has completed.

     *

     * @since Symbian^4

     * @param aActive Pointer to the active object that completed.

     * @param aStatus The status of the completed request.

     */

    virtual void RequestCompletedL( CBtSimpleActive* aActive, TInt aStatus ) = 0;

    /**

     * Callback from Docancel() for handling cancelation of an outstanding request.

     *

     * @since Symbian^4

     * @param aId The ID that identifies the outstanding request.

     */

    virtual void CancelRequest( TInt aRequestId ) = 0;

    /**

     * Callback from RunError() to notify that an error has occurred in RunL.

     *

     * @since Symbian^4

     * @param aActive Pointer to the active object that completed.

     * @param aError The error occurred in RunL.

     */

    virtual void HandleError( CBtSimpleActive* aActive, TInt aError ) = 0;

    };

/**

 *  Class CBtSimpleActive.

 *  

 *  This Active Object provides its client a TRequestStatus for performing 

 *  asynchronous requests. It does not know the detail of the asynch operation.

 *  All of AO callbacks, such as RunL, will be delegated to the client

 *  for processing, via interface MBtSimpleActiveObserver.

 *  

 */

NONSHARABLE_CLASS ( CBtSimpleActive ): public CActive

    {

public:

    /**

     * Two-phase constructor

     *

     * @since Symbian^4

     * @param aObserver Pointer to callback interface that receives notification

     *                  that the request has been completed.

     * @param aId Identifier for the CBtSimpleActive instance.

     * @param aPriority The priority of the active object.

     * @return Pointer to the constructed CBtSimpleActive object.

     */

    IMPORT_C static CBtSimpleActive* NewL( MBtSimpleActiveObserver& aObserver, TInt aId,

                                TInt aPriority = CActive::EPriorityStandard );

    /**

     * Destructor

     */

    IMPORT_C virtual ~CBtSimpleActive();

    /**

     * Get the request ID of this active object.

     *

     * @since Symbian^4

     * @return The request ID of this active object.

     */

    IMPORT_C TInt RequestId();

    /**

     * Set a new request ID for this active object.

     *

     * @since Symbian^4

     * @param The new request ID of this active object.

     */

    IMPORT_C void SetRequestId( TInt aId );

    /**

     * Activate the active object.

     *

     * @since Symbian^4

     */

    IMPORT_C void GoActive();

    /**

     * Get a reference to the active object request status.

     *

     * @since Symbian^4

     * @return Reference to the active object request status.

     */

    IMPORT_C TRequestStatus& RequestStatus();

private:

// from base class CActive

    /**

     * From CActive.

     * Called by the active scheduler when the request has been cancelled.

     *

     * @since S60 v3.2

     */

    void DoCancel();

    /**

     * From CActive.

     * Called by the active scheduler when the request has been completed.

     *

     * @since S60 v3.2

     */

    void RunL();

    /**

     * From CActive.

     * Called by the active scheduler when an error in RunL has occurred.

     *

     * @since S60 v3.2

     */

    TInt RunError( TInt aError );

private:

    /**

     * C++ default constructor

     *

     * @since S60 v3.2

     * @param aObserver Pointer to callback interface that receives notification

     *                  that the request has been completed.

     * @param aId ID of the request (for the client to keep track of multiple 

     *            active objects).

     * @param aPriority Priority of 

     */

    CBtSimpleActive( MBtSimpleActiveObserver& aObserver, TInt aId, TInt aPriority );

private: // data

    /**

     * ID of the request (used only by our client).

     */

    TInt iRequestId;

    /**

     * Our observer.

     * Not own.

     */

    MBtSimpleActiveObserver& iObserver;

    };

#endif // BTSIMPLEACTIVE_H