/*

* Copyright (c) 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:  Active object to split up long running tasks

*

*/

#ifndef C_MPXDBACTIVETASK_H

#define C_MPXDBACTIVETASK_H

#include <mpxcommand.h>

#include <mpxmessage2.h>

/**

* Observer class to the active task object

*/

NONSHARABLE_CLASS( MMPXDbActiveTaskObserver )

    {

public:

    /**

    * Handle the execution of a step

    * @return ETrue if complete, EFalse if more to do

    */

    virtual TBool HandleStepL() = 0;

    /**

    * Handle the completion of the operation

    */

    virtual void HandleOperationCompleted( TInt aErr ) = 0;

    };

/**

 *  Active object to execute tasks in multiple steps

 *  Each collection plugin has its own task queue, which serializes all

 *  operations for a plugin

 *  @lib mpxdbplugin

 *  @since S60

 */

NONSHARABLE_CLASS( CMPXDbActiveTask ) : public CActive

    {

public:

    /**

    * Two-phased constructor

    */

    IMPORT_C static CMPXDbActiveTask* NewL( MMPXDbActiveTaskObserver& aObserver );

    /**

    * Destructor

    */

    IMPORT_C virtual ~CMPXDbActiveTask();

public:    // Accessor functions

    /**

    * Start the async command task

    * @param aTask task id

    * @param aCommand command for the operation

    */

    IMPORT_C void StartL( TMPXCommandId aTask, const CMPXCommand& aCommand );

    /**

    * Get the current step for the current task

    * @return the current step

    */

    IMPORT_C TInt GetStep();

    /*

    * Get the command for the current task

    * @return the current task

    */

    IMPORT_C TMPXCommandId GetTask();

    /**

    * Get the command for the current task

    * @return the current command

    */

    IMPORT_C CMPXCommand& GetCommand();

    /**

    * Get the current change message array

    * @return get the change messages

    */

    IMPORT_C CMPXMessageArray& GetChangeMessages();

    enum TChangeVisibility

        {

        ENotVisibile,

        ESingleVisible,

        EAllVisible

        };

    /**

    * Set if the change is visible

    * @param aChange change state

    */

    IMPORT_C void SetVisibleChange( TChangeVisibility aChange );

    /**

    * Return if the change is visible

    * @return visible change state

    */

    IMPORT_C TChangeVisibility GetVisibleChange();

protected: // From base class

    /**

    * From CActive

    */

    IMPORT_C void RunL();

    /**

    * From CActive

    */

    IMPORT_C void DoCancel();

    /**

    * From CActive

    */

    IMPORT_C TInt RunError( TInt aError );

private:

    /**

    * Default Constructor

    */

    CMPXDbActiveTask(MMPXDbActiveTaskObserver& aObserver);

    /**

    * 2nd-phase Constructor

    */

    void ConstructL();

private: // data

    CMPXCommand*  iCurCommand;  // Current Command

    TMPXCommandId iCurTask;  // The task command id

    TInt          iCurStep;  // The n-th stop in the operation

    TChangeVisibility iCurVisibleChange; // Is the operation UI visible

    CMPXMessageArray* iChangeMessages; // Change message array

    MMPXDbActiveTaskObserver& iObserver; // Observer

    };

#endif // C_MPXDBACTIVETASK_H