/*

* Copyright (c) 2007-2009 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:  Maintains a list of process ids and matching origin*

*/

#ifndef __PROCESSORIGINMAPPER_H__

#define __PROCESSORIGINMAPPER_H__

#include <e32cmn.h>

#include <s32file.h>

#include "mdeconstants.h"

#include "processoriginmapperinterface.h"

/**

 * @var Data transfer object used for process/origin

 * mapping table.

 */

struct TProcessOriginPair

    {

    TUid iProcessId;

    TOrigin iOrigin;

    };

/**

 * @var Maximum amount of items allowed in the mapping table.

 */

const TInt KMaxMappingSize = 100;

/**

 * Maintains a list of process ids and matching origin

 * values to be set for mde objects created by a process.

 * List is maintained in memory and in a text file.

 * 

 * API is provided to add and remove processes in the list

 * and to retrieve the matching origin by a process id (if any).

 * Mappings are read written to a file on request.

 */

class CProcessOriginMapper : public CBase,

                             public MProcessOriginMapperInterface

    {

    public:

        /**

         * Creates and constructs a new instance of CLocationContextPlugin.

         * Two-phase construction.

         *

         * @return A pointer to the created instance.

         */

        static CProcessOriginMapper* NewL();

        /**

         * Destructor.

         */

        virtual ~CProcessOriginMapper();

    private:

        /**

         * Private constructor, called by NewL() only.

         */

        CProcessOriginMapper();

        /**

         * Second phase construction called by NewL().

         */

        void ConstructL();

    public:

        /**

         * Add a process to the list.

         * @param aProcessUid  Uid of the process to add.

         * @param aOrigin      Origin to which this process will mapped to.

         */

        void RegisterProcessL( const TUid& aProcessId,

                               const TOrigin& aOrigin );

        /**

         * Remove a process from the list.

         * @param aProcessId  Uid of the process to remove.

         */

        void UnregisterProcessL( const TUid& aProcessId );

        /**

         * Check a process from the list.

         * @param aProcessId  Uid of the process to check.

         * @return  Origin the given process is mapped to

         *          or KErrNotFound if not found.

         */

        TOrigin OriginL( const TUid& aProcessId );

        /**

         * Read process id mappings from a file.

         * This doesn't clear the list of currently registered mappings.

         * @param aFile  File name and path.

         * @return Count of mapping pairs read.

         */

        TInt ReadFileL( const TDesC& aFile );

        /**

         * Read process id mappings from the default file.

         * @return Count of mapping pairs read.

         */

        TInt ReadFileL();

        /**

         * Write process id mappings to a file.

         * @param aFile  File name and path.

         */

        void WriteFileL( const TDesC& aFile );

        /**

         * Write process id mappings to the default file.

         */

        void WriteFileL();

        /**

         * Clear mapping table in memory.

         */

        void Clear();

        /**

         * Count of registered mappings.

         * @return Count

         */

        TInt Count();

    private:

        /**

         * Find an index by process id.

         * @param aProcessId  Process id.

         * @return  Index or KErrNotFound if not found.

         */

        TInt FindProcess( const TUid& aProcessId );

        /**

         * Read one process id and origin pair from file.

         * @param aProcessUid  Uid of the process to add.

         * @param aOrigin      Origin to which this process will mapped to.

         */

        void ReadProcessOriginPairL( TUid& aProcessId, TOrigin& aOrigin );

        /**

         * Write one related process/origin pair to a file.

         * @param aProcessUid  Uid of the process to add.

         * @param aOrigin      Origin to which this process will mapped to.

         */

        void WriteProcessOriginPairL( TUid& aProcessId, TOrigin& aOrigin );

    private: // data

        /**

         * @var Mapping table. It holds pairs of

         * matching process ids and origins.

         * Content is loaded from and saved to a file.

         */

        RArray<TProcessOriginPair> iProcessOriginMap;

        /**

         * File system session.

         */

        RFs iFs;

        /**

         *  File stream used for reading the import file

         */

        RFileReadStream iReadStream;

        /**

         *  File stream used for writing the export file

         */

        RFileWriteStream iWriteStream;

        /**

         * A buffer used for reading lines from files.

         */

        HBufC8* iLineBuffer;

        /**

         * Indicates read defult origin map file.

         * No write process should occur.

         */

        TBool iDefaultFileRead;

    };

#endif