/*

* Copyright (c) 2009 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: Support for executing asynchronously certain plugin

* operations.

*/

#ifndef __BASEPLUGINDELAYEDOPS_H__

#define __BASEPLUGINDELAYEDOPS_H__

#include <e32base.h>

class CBasePlugin;

class CDelayedOp;

/**

 * The interface to the delayed operations manager implementation. Plugins

 * must talk to the manager only through this interface.

 */

class MDelayedOpsManager

    {

public:

    /**

     * 

     */

    virtual ~MDelayedOpsManager() {};

    /**

     * @param aOp ownership is transferred 

     */

    virtual void EnqueueOpL( CDelayedOp* aOp ) = 0;

    /**

     * @param aOp the caller must delete the operation

     */

    virtual void DequeueOp( const CDelayedOp& aOp ) = 0;

    /**

     * API for future extensions.

     */

    virtual TInt Extension1(

        TUint aExtensionId, TAny*& a0, TAny* a1 ) = 0;

    };

/**

 * The base class for the delayed operations. All of the delayed operations must

 * derive from it.

 */

class CDelayedOp : public CAsyncOneShot

    {

public:

    IMPORT_C virtual ~CDelayedOp();

    IMPORT_C void SetContext(

        CBasePlugin& aPlugin,

        MDelayedOpsManager& aManager );

    /**

     * Derived classes must implement their asynchronous processing in this

     * method. The GetPlugin method can only be used from within this method.

     */

    virtual void ExecuteOpL() = 0;

protected:

    IMPORT_C CDelayedOp();

    /**

     * Returns the plugin instance associated with this operation. Available

     * only from within the ExecuteOpL method.

     */

    IMPORT_C CBasePlugin& GetPlugin();

private:

    IMPORT_C virtual void RunL();

    IMPORT_C virtual void DoCancel();

private:

    MDelayedOpsManager* iManager;   //not owned

    CBasePlugin* iPlugin;           //not owned

    __LOG_DECLARATION

    };

#endif // __BASEPLUGINDELAYEDOPS_H__