/*

* Copyright (c) 2006-2007 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:  Background thread functionality wrapper

*

*/

#ifndef CFILEMANAGERTHREADWRAPPER_H

#define CFILEMANAGERTHREADWRAPPER_H

// INCLUDES

#include <e32base.h>

#include "MFileManagerThreadFunction.h"

// CLASS DECLARATION

/**

*  The class implements a background thread functionality wrapper

*

*  @lib FileManagerEngine.lib

*  @since 3.1

*/

NONSHARABLE_CLASS(CFileManagerThreadWrapper) : public CActive

    {

    public:

        static CFileManagerThreadWrapper* NewL();

        ~CFileManagerThreadWrapper();        

    public: // New functions

        /**

        * Starts background thread. Can be used only by client thread.

        * @since 3.1

        * @param aFunction Reference to background thread abstraction.

        * @param aPriority background thread priority

        * @param aNotify client notify flags

        *        see MFileManagerThreadFunction::TNotifyType

        * @return System wide error code

        */

        TInt StartThread(

            MFileManagerThreadFunction& aFunction,

            TUint aNotify,

            TThreadPriority aPriority );

        /**

        * Cancels background thread.

        * Background thread is exited when ongoing ThreadStepL is finished.

        * Can be used only by client thread.

        * @since 3.1

        */

        void CancelThread();

        /**

        * Checks if background thread has been canceled.

        * Can be used by both client and background threads.

        * E.g. checks can be done inside long running ThreadStepL.

        * @since 3.1

        * @return ETrue if canceled, otherwise EFalse

        */

        TBool IsThreadCanceled() const;

        /**

        * Resumes thread when called after error or step finished 

        * notification. Can only be used by client thread.

        * @since 3.2

        */

        void ResumeThread();

        /**

        * Checks if thread has been started

        * notification. Can only be used by client thread.

        * @since 3.2

        * @return ETrue if started, otherwise EFalse

        */

        TBool IsThreadStarted() const;

    private: // From CActive

        void RunL();

        TInt RunError( TInt aErr );

        void DoCancel();

    private:

        CFileManagerThreadWrapper();

        void ConstructL();

        static TInt ThreadFunction( TAny* ptr );

        void ThreadFunctionL();

        TInt NotifyClientAndWaitConfirm( TInt aErr );

        void DoNotifyL( TInt aErr );

        NONSHARABLE_CLASS(CNotifyObserver) : public CActive

            {

            public:

                static CNotifyObserver* NewL(

                    CFileManagerThreadWrapper& aWrapper );

                ~CNotifyObserver();

                void Activate();

                void Complete( RThread& aThread, TInt aResult );

            private: // From CActive

                void RunL();

                TInt RunError( TInt aErr );

                void DoCancel();

            private:

                CNotifyObserver( CFileManagerThreadWrapper& aWrapper );

            private:

                CFileManagerThreadWrapper& iWrapper;

            };

    private: // Data

        // Own: For synchronising client and background thread

        RSemaphore iSemaphore;

        // Own: Client thread id

        TThreadId iClientId;

        // Ref: Pointer to thread function

        MFileManagerThreadFunction* iFunction;

        // Own: Client notify type flags, Client writes and thread only reads

        TUint iNotify;

        // Own: Thread cancel indicator, Client writes and thread only reads

        TBool iCancel;

        // Own: Observer wrapper to notify client about thread events

        CNotifyObserver* iNotifyObserver;

        // Own: Thread resume pending indicator, Client reads and writes

        TBool iResumePending;

    };

#endif // CFILEMANAGERTHREADWRAPPER_H

// End of File