/*

* Copyright (c) 2004 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:     HW Device for speech recognition

*

*/

#ifndef ASRSRECOGNITIONHWDEVICE_H

#define ASRSRECOGNITIONHWDEVICE_H

//  INCLUDES

#include <asrshwdevice.h>

// FORWARD DECLARATIONS

class CSDModelBank;

class CSIModelBank;

class CRecognitionAlgorithm;

// CLASS DECLARATION

/**

*  Observer for recognition HW device

*

*  @lib asrsrecognitionhwdevice.lib

*  @since 2.8

*/

class MASRSRecognitionHwDeviceObserver 

    {

    public: // New functions

        /**

        * Called by the hardware device when the InitializeL() method has completed.

        * @since 2.8

        * @param aError Initialization result code. 

        *               KErrNone if successful otherwise a system-wide error code.

        * @return none

        */

        virtual void MarhdoInitializationComplete( TInt aError ) = 0;

        /**

        * Called by the hardware device when the  InitializeL() method has completed.

        * @since 2.8

        * @param aError Initialization result code. 

        *               KErrNone if successful otherwise a system-wide error code.

        * @return none

        */

        virtual void MarhdoInitRecognizerFEComplete( TInt aError ) = 0;

        /**

        * Called by the hardware device when backend initialization is completed.

        * @since 2.8

        * @param aError Initialization result code. 

        *               KErrNone if successful otherwise a system-wide error code.

        * @return none

        */

        virtual void MarhdoInitRecognizerBEComplete( TInt aError ) = 0;

        /**

        * Called by the hardware device when recognition result is available.

        * @since 2.8

        * @param aError Recognition result code. KErrNone if successful.  

        *               KErrRejected if the recognition result is rejected, 

        *               otherwise a system-wide error code

        * @return none

        */ 

        virtual void MarhdoRecognitionComplete( TInt aError ) = 0;

        /**

        * Called by the hardware device when end-of-utterance is detected by the 

        * acoustic frontend. This method must be called before MarhdoRecognitionComplete().

        * @since 2.8

        * @param aError Recognition result code. KErrNone if successful, otherwise KErrTooLong, 

        *               KErrTooShort, KErrAsrSpeechTooEarly, KErrNoSpeech

        * @return none

        */

        virtual void MarhdoEouDetected( TInt aError ) = 0;

        /**

        * Called by the hardware device when a feature vector is extracted by acoustic frontend.

        * @since 2.8

        * @param aFV A buffer containing a feature vector.

        * @param aSNR Signal-to-noise ratio.

        * @param aPosition Indicates whether this is the first, subsequent or last feature vector in a series.

        * @return none

        */

        virtual void MarhdoFeatureVector( const TDesC8& aFV, TInt32 aSNR, TInt32 aPosition ) = 0;

        /**

        * Called by the hardware device to request for utterance data. 

        * The response to the request is sent in SendSpeechData().

        * @since 2.8

        * @param none

        * @return none

        */

        virtual void MarhdoRequestSpeechData () = 0;

    };

/**

*  Recognition HW Device

*

*  @lib asrsrecognitionhwdevice.lib

*  @since 2.8

*/

class CASRSRecognitionHwDevice : public CASRSHwDevice

    {

    public:  // Constructors and destructor

        /**

        * Two-phased constructor.

        */

        IMPORT_C static CASRSRecognitionHwDevice* NewL( MASRSRecognitionHwDeviceObserver& aObserver );

        /**

        * Destructor.

        */

        IMPORT_C virtual ~CASRSRecognitionHwDevice();

    public: // New functions

        /**

        * This method initializes the backend of the recognition Hw device.

        * @since 2.8

        * @param aRecognitionData A recognition data generated by grammar compilation.

        * @param aModels A model bank containing acoustic models 

        * @return none

        */

        IMPORT_C void InitRecognizerBEL( const TDesC8& aRecognitionData, 

                               const CSIModelBank& aModels );

        /**

        * This method initialize the frontend of the recognition Hwdevice

        * @since 2.8

        * @param none

        * @return none

        */  

        IMPORT_C void InitRecognizerFEL( TBool aSendFeatureVectors = EFalse );

        /**

        * Sets the maximum number of entries wanted in the ranked list of recognition results. 

        * @since 2.8

        * @param aNBest The n-best number.

        * @return none

        */ 

    	IMPORT_C void SetNBest( TUint32 aNBest );

    	/**

        * Sets the rejection threshold. 

        * @since 3.2

        * @param aRejection Rejection threshold value.

        * @return none

        */ 

    	IMPORT_C void SetRejection( TUint32 aRejection );

    	/**

        * Gets the rejection threshold. 

        * @since 2.8

        * @param none

        * @return Rejection threshold value.

        */ 

    	IMPORT_C TUint32 GetRejection();

        /**

        * Start recognition

        * @since 2.8

        * @param aNBestList At the end of recognition, this object will contain Nbest list IDs.

        * @param aScore At the end of recognition, this object will contain scores for Nbest list.

        * @param aSendFeatureVectors ETrue send feature vector to client, EFalse do not send feature vector to client.

        * @return none

        */ 

        IMPORT_C void StartRecognitionL( RArray<TUint>& aNBestList, RArray<TInt>& aScore );

        /**

        * Stop a started recognition process.

        * @since 2.8

        * @param none

        * @return none

        */ 

        IMPORT_C void StopRecognition();

        /**

        * Use to send utterance data

        * @since 2.8

        * @param aBuffer Buffer containing utterance data.

        * @param aEnd End of utterance data indicator. ETrue indicates end of data or no data.

        * @return none

        */ 

        IMPORT_C void SendSpeechData( TPtrC8& aBuffer, TBool aEnd );

    public: // Functions from base classes

        /**

        * From CASRSHwDevice Use to initilize HW device

        * @since 2.8

        * @param none

        * @return none

        */

        IMPORT_C virtual void InitializeL();

        /**

        * From CASRSHwDevice Use to clear HW device

        * @since 2.8

        * @param none

        * @return none

        */

        IMPORT_C virtual void Clear();

		/**

        * From CASRSHwDevice Use to get custom interface

        * @since 2.8

        * @param aInterfaceId Identifier of the intercace implementation

        * @return Pointer to the interface implementation or NULL.

        */

        IMPORT_C virtual TAny* CustomInterface( TUid aInterfaceId );

    private:

        /**

        * C++ default constructor.

        */

        CASRSRecognitionHwDevice();

        /**

        * By default Symbian 2nd phase constructor is private.

        */

        void ConstructL( MASRSRecognitionHwDeviceObserver& aObserver );

    private:    // Data

        // Actual implementation of recognition

        CRecognitionAlgorithm* iRecAlgorithm;

        // Reserved pointer for future extension

        TAny* iReserved;

    };

#endif      // ASRSRECOGNITIONHWDEVICE  

// End of File