/*

* Copyright (c) 2004-2006 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:  CContext class provides context processing. It implements 

*               MNssContext interface.

*

*/

#ifndef NSSVASCCONTEXT_H

#define NSSVASCCONTEXT_H

//  INCLUDES

#include <nsssispeechrecognitiondatacommon.h>

#include "nssvascoreconstant.h"

#include "nssvasmcontext.h"

#include "nssvasccontextsrsportal.h"

#include "nssvasmcoresrsdbeventhandler.h"

#include "nssvascoreconstant.h"

class CNssContextSrsPortal;

// CLASS DECLARATION

/**

*  CContext is the implementation class for MNssContext. 

*  It encapsulates context data. A context cannot be directly created by a 

*  client. A client has to own an instance of Context Manager which has methods 

*  for creating context objects. The CContext class also provides additional 

*  members for internal use by NssVAS.

*  @lib NssVASApi.lib

*  @since 2.0

*/

class CNssContext: public CBase, public MNssContext

{

public:

    /**

    * C++ constructor.

    */

	CNssContext(CNssContextSrsPortal* aContextSrsPortal);

    /**

    * Destructor.

    */

	~CNssContext();

public: // functions for internal VAS use

    /**

    * Get the context id

	* for internal use

	* @since 2.0

    * @param 

    * @return context id

    */

	TInt ContextId() const;

    /**

    * Get the grammar id

	* for internal use

	* @since 2.0

    * @param 

    * @return grammar id

    */

	TUint32 GrammarId() const;

	/**

    * Get the lexicon id

	* for internal use

	* @since 2.0

    * @param 

    * @return lexicon id

    */

	TUint32 LexiconId() const;

	/**

    * Get the model bank id

	* for internal use

	* @since 2.0

    * @param 

    * @return model bank id

    */

	TUint32 ModelBankId() const;

	/**

    * Get the recognition mode

	* for internal use

	* @since 2.8

    * @param none

    * @return recognition technology (SI / SD)

    */

	TNSSRecognitionMode RecognitionMode() const;

    /**

    * Set the context id 

	* for internal use

	* @since 2.0

    * @param aContextId - the context id 

    * @return 

    */

	void SetContextId(TInt aContextId);

	/**

    * Set the grammar id 

	* for internal use

	* @since 2.0

    * @param aGrammarId - the grammar id

    * @return 

    */

	void SetGrammarId(TUint32 aGrammarId);

	/**

    * Set the lexicon id

	* for internal use

	* @since 2.0

    * @param aLexiconId - the lexicon id

    * @return id

    */

	void SetLexiconId(TUint32 aLexiconId);

	/**

    * Set the model bank id

	* for internal use

	* @since 2.0

    * @param aModelBankId - the model bank id

    * @return id

    */

	void SetModelBankId(TUint32 aModelBankId);

    /**

    * Set the speech technology (Speaker independent or dependent)

    * for internal use

    * @since 2.0

    * @param aRecognitionMode - the recognition mode

    * @return none

    */

    void SetRecognitionMode(TNSSRecognitionMode aRecognitionMode);

	/**

    * Save the context to the SRS. 

	* for internal use

	* This method is used to save the context to the SRS.

	* This creates the model bank, 

	* lexicon, and grammar for a context. Model bank, and lexicon 

	* are created only for the first time, and are thus, fixed.

	* For every context, there is one grammar id. After, model bank,

	* lexicon, and grammar are created, the corresponding Ids are 

	* set in the context object.

	* @since 2.0

    * @param

    * @return none

    */

	void BeginSaveToSrsL(MNssCoreSrsDBEventHandler* aSrsDBEventHandler);

	/**

    * Delete the context from the SRS. 

	* for internal use

	* deletes grammar from SRS

	* @since 2.0

    * @param 

    * @return none

    */

	void BeginDeleteFromSrsL(MNssCoreSrsDBEventHandler* aSrsDBEventHandler);

	/**

    * Commit the context from the SRS. 

	* for internal use

	* Commit the changes from SRS

	* @since 2.0

    * @param 

    * @return 

    */

	TInt CommitSrsChanges();

	/**

    * Don't commit the context from the SRS. 

	* for internal use

	* Doesn't commit the changes from SRS

	* @since 2.8

    * @param 

    * @return 

    */

	TInt RollbackSrsChanges();

    /**

    * Set/Reset the iModelBankAndLexiconExist flag.

	* for internal use

	* @since 2.0

    * @param aVal, ETrue to set, EFalse to reset

    * @return 

    */

	void SetModelBankAndLexiconExist(TBool aVal);

	/**

    * Get the iModelBankAndLexiconExist flag

	* for internal use

	* @since 2.0

    * @param 

    * @return ETrue if set, else EFalse

    */

	TBool ModelBankAndLexiconExist();

	/**

    * overloaded assignment operator

	* for internal use

	* @since 2.0

    * @param reference to context

    * @return reference to the context

    */

	CNssContext& operator=(const CNssContext& aContext);

	/**

    * Create a copy of the context. 

	* for internal use

	* This function creates a new context by allocating memory for

	* a new context, and deep copying the members of the context on which

	* this fucntion is called. Old context and new context exist. Client need

	* to deallocate memory.

	* @since 2.0

    * @param 

    * @return pointer the newly created context.

    */

	CNssContext* CopyL();

    /**

    * Sets/Resets the client data. The data must be saved with

    * MNssContextMgr::SaveClientData after this call.

    * @since 2.8

    * @param aData At most 100 bytes of serialized client data.

    */

    void SetClientData(const TDesC8& aData);

    /**

    * Gets the client data.

    * @since 2.8

    * @return At most 100 bytes of data.

    */

    const TDesC8& ClientData();

public: // functions derived from MNssContext

   /**

   * Get the name of the context

   * @since 2.0

   * @param 

   * @return reference to name of context

   */  

   TDesC& ContextName();

	/**

   * Is the context global

   * @since 2.0

   * @param 

   * @return ETrue if context is global, EFalse otherwise

   */  

   TBool IsGlobal();

	/**

    * Sets the name of the context

	* @since 2.0

    * @param aName name of the context as a descriptor

    * @return 

    */  

    void SetNameL(const TDesC& aName);

   /**

   * Sets/Resets the global flag for the context

   * @since 2.0

   * @param aGlobal ETrue to set the context as global, EFalse as not global 

   * @return 

   */  

   void SetGlobal(TBool aGlobal);

private: // data

	// name of the context

	HBufC*				iName;

	// context id, used by the VAS DB

	TInt				iContextId;

	// global flag

	TBool				iGlobal;

	// grammar id

	TUint32		        iGrammarId;

	// lexicon id

	TUint32             iLexiconId;

	// model bank id

	TUint32             iModelBankId;

	// association to context srs portal 

	CNssContextSrsPortal*	iContextSrsPortal;

	// flag to denote if Model Bank and Lexicon already created

	TBool				iModelBankAndLexiconExist;

    // differentiates between SI and SD contexts

    TNSSRecognitionMode iRecognitionMode;

    // client payload data

    TBuf8<100>          iClientData;

};

#endif // NSSVASCCONTEXT  

// End of File