/*

* 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: 

*

*/

#ifndef CREQUESTCHECKER_H

#define CREQUESTCHECKER_H

#include <e32base.h>

#include <mtp/mtpprotocolconstants.h>

#include <mtp/tmtptyperequest.h>

class CMTPObjectMetaData;

class MMTPDataProviderFramework;

class MMTPConnection;

/**

* element type in the request

*/

enum TMTPElementType

    {

    /**

    * Session ID type

    */

    EMTPElementTypeSessionID,

    /**

    * Object Handle type

    */

    EMTPElementTypeObjectHandle,

    /**

    * Format code type

    */

    EMTPElementTypeFormatCode,

    /**

    * Storeage Id type

    */

    EMTPElementTypeStorageId,

    };

/**

* element attribute to check in the reqeust

*/

enum TMTPElementAttr

    {

    /**

    * no attribute to check

    */

    EMTPElementAttrNone = 0x0000,

    /**

    * the object/storage should be readable

    */

    EMTPElementAttrRead = 0x0001,

    /**

    * the object/storage should be writable

    */

    EMTPElementAttrWrite = 0x0002,

    /**

    * the object should be a file

    */

    EMTPElementAttrFile = 0x0004,

    /**

    * the object should be a directory

    */

    EMTPElementAttrDir = 0x0008,

    /**

    * supported format array

    */

    EMTPElementAttrFormatEnums = 0x0010,

    /**

    * The object can be either a file or directory.

    */

    EMTPElementAttrFileOrDir = 0x0020,

    };

/**

* defines the verification data structure

*/

struct TMTPRequestElementInfo

    {

    TMTPTypeRequest::TElements iElementIndex; //which element in the request to check

    TMTPElementType iElementType; //the type of the element

    TInt iElementAttr; //the attribute of the element

    TInt iCount; //number of special values (0, 1, 2)

    TUint32 iValue1; //special value 1

    TUint32 iValue2; //special value 2

    };

/**

* defines a generic request verification class.  It iterates through the verification data elements,

* and performs the check based on the element type/attribute.

*/

class CRequestChecker : public CBase

    {

public:

    /**

    * Two-phase construction method

    * @param aFramework   The data provider framework

    * @param aConnection  The connection object

    * @return a pointer to the created request checker object

    */

    static CRequestChecker* NewL( MMTPDataProviderFramework& aFramework,

            MMTPConnection& aConnection );

    /**

    * Destructor

    */

    ~CRequestChecker();

    /**

    * Verfiy the request.  It check the request header first (session id and transaction code), and check for special values, last

    * it iterates through the verification elements for checking individul parameters in the request

    * @param aRequest The request object to verify

    * @param aCount   The number of verification elements

    * @param aElementInfo The array of verification elements

    * @return reponse code to return to the initiator

    */

    TMTPResponseCode VerifyRequestL( const TMTPTypeRequest& aRequest,

        TInt aCount,

        const TMTPRequestElementInfo* aElementInfo );

    /**

    * Return the object info for the handle.

    * This is to remove extra expensive DMBS retrieval operations.

    * @param aHandle  the handle of the object requested

    * @return an object info for the handle

    */

    CMTPObjectMetaData* GetObjectInfo( TUint32 aHandle ) const;

private:

    /**

    * Check the request header portion (session Id and transaction code)

    * @param aRequest the request object to check

    * @return repsonse code to return to initiator

    */

    TMTPResponseCode CheckRequestHeader( const TMTPTypeRequest& aRequest ) const;

    /**

    * Check the session id in the request parameter (NOTE the session id is different from the one in the request header),

    * this usually only applies to the OpenSession request

    * @param aSessionId   Session id of the request.

    * @param aElementInfo ElementInfo data array to check against.

    * @return repsonse code to return to initiator

    */

    TMTPResponseCode VerifySessionId( TUint32 aSessionId,

        const TMTPRequestElementInfo& aElementInfo ) const;

    /**

    * Check the object handle in the request parameter, whether the handle is in the object store, read/write, file/dir

    * @param aHandle  Object handle to be checked.

    * @param aElementInfo Element info array to be checked against.

    * @return repsonse code to return to initiator

    */

    TMTPResponseCode VerifyObjectHandleL( TUint32 aHandle,

        const TMTPRequestElementInfo& aElementInfo );

    /**

    * Check the storage id parameter in the request, read/write attributes

    * @param aStorageId   Storage id to be checked.

    * @param aElementInfo Element info array to be checked against.

    * @return repsonse code to return to initiator

    */

    TMTPResponseCode VerifyStorageIdL( TUint32 aStorageId,

        const TMTPRequestElementInfo& aElementInfo ) const;

    /**

    * Check the format code parameter in the request,

    * @param aStorageId   aFormatCode to be checked.

    * @param aElementInfo Element info array to be checked against.

    * @return repsonse code to return to initiator

    */

    TMTPResponseCode VerifyFormatCode( TUint32 aFormatCode,

        const TMTPRequestElementInfo& aElementInfo ) const;

    /**

    * Check if the parameter is one of the special values

    * @param aParameter   The parameter value in the request

    * @param aElementInfo The ElementInfo for the parameter

    * @return ETrue if the parameter is one of the special values, otherwise, EFalse

    */

    TBool IsSpecialValue( TUint32 aParameter,

        const TMTPRequestElementInfo& aElementInfo ) const;

private:

    /**

    * Standard c++ constructor

    */

    CRequestChecker( MMTPDataProviderFramework& aFramework,

        MMTPConnection& aConnection );

    /**

    * Two-phase construction

    */

    void ConstructL();

private:

    MMTPDataProviderFramework& iFramework;

    MMTPConnection& iConnection;

    RArray<TUint32> iHandles; //these two arrays contain the mapping from the handle to objectinfo

    RPointerArray<CMTPObjectMetaData> iObjectArray;

    };

#endif // CREQUESTCHECKER_H