/*

* Copyright (c) 2005-2009 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 BTGPSFIX_H

#define BTGPSFIX_H

//  INCLUDES

#include <lbsposition.h>

#include <lbs.h>

#include <e32std.h>

#include "BTGPSMessageDef.h"

// CONSTANTS

//The maximum number of satellites the GPS can track at once

static const TInt KMaxNumberOfSatellites = 12;

//The maximum number of GSV sentence that specified in NMEA spec

const TInt KMaxGSVMessageNumber = 9;

//The maximum length of GSV sentence

const TInt KMaxGSVLength = 82;

// MACROS

// DATA TYPES

// FUNCTION PROTOTYPES

// FORWARD DECLARATIONS

class TBTGPSNmeaParser;

class CBTGPSNmeaBuffer;

// CLASS DECLARATION

/**

*  Class for parsing NMEA sentences and storing the information about the fix.

*  Parsing:

*       - If lexition parsing failed, the whole NMEA sentence is ignored

*       - NULL field is acceptable for any field, even explicitly specified in

*         NMEA spec that can't be NULL

*       - Only all RMC, GGA, GSA sentence are received, then the fix information

*         is valid. 

*       - GSV recieved time is stored for checking GSV validity

*

*/

class CBTGPSFix : public CBase

    {

    public:

        /**

        *Enumerate the status of fix parsing. The value is used when a NMEA sentence

		*is parsed by this class.

        */

        enum TParsingStatus

            {

            EInvalid,       ///The NMEA sentence is invalid

            EInfoUpdated,   ///The NMEA sentence is valid and information updated

            EUnkown         ///The NMEA sentence is not supported by parser

            };

        /**

        *Enumerate the different qualities of fix. This information is specified

        *in GSA sentence

        */

        enum TState

            {

            EFixValidityUnkown, ///No GSA sentence received.

            EFixNotValid,       ///Not a valid fix.

            EFixValid2D,        ///2D fix made

            EFixValid3D         ///3D fix made

            };

    public:  // Constructors and destructor

        /**

        * Constructor.

        */

        CBTGPSFix();

        /**

        * Set NMEA Buffer

        */

        void SetNmeaBuffer(CBTGPSNmeaBuffer* aNmeaBuffer);

    public:  // New functions

        /**

        * Resets the all fix parameters.

        */

        void Reset();

        /**

        * Reset fix parameter except setellites in view information(GSV information)

        */

        void ResetFix();

        /**

        * Reset GSV time

        */

        void ResetGSVTime();

        /**

        * Parse message.

		* @param aMsg Received message.

		* @return Parsing status as specified in CBTGPSFix::TParsingStatus.

        */

        TParsingStatus ParseMessage(const TBTGPSNmeaParser& aParser);

        /**

        * Get fix state(not valid, 2d fix or 3d fix)

		* @return Fix state as specified in CBTGPSFix::TState

        */

        TState FixState() const;

        /**

        * Check if fix is valid

		* @return Return ETrue if fix is valid

        */

        TBool IsFixValid() const;

        /**

        * Check if full NMEA message pattern received. 

		* @return Return ETrue if GSA, RMC and GGA are received.

        */

        TBool IfFullNmeaPatternReceived() const;

        /**

        * Get fix time. Fix time is updated when new latitude and

		* longitude are received.

		* @return Fix received time.

        */

        TTime FixTime() const;

        /**

        * Get GSV time

		* @return Return GSV sentence received time.

        */

        TTime GsvTime() const;

        /**

        * Fill fix into to TPositionInfo. Non-leave function.

        */

        TInt FillPositionInfo(

            TPositionInfoBase& aPosInfo,

            TInt* aNmeaIndex = NULL) const;

        /**

        * Fill fix info to TPositionInfo.

        * If fix is not available, then aPosInfo will be emptied.

		* @param aPosInfo The TPositionInfo object to fill the fix info

		* @param aNmeaIndex The pointer to the index where last time

		* NMEA message is retruned to client. On return this value

		* is updated to the current bottom of the NMEA buffer;

        */

        void FillPositionInfoL(

            TPositionInfoBase& aPosInfo,

            TInt* aNmeaIndex = NULL) const;

        /**

        * Validate the NMEA buffer index. Client shall keep the 

        * index in the FIFO circulate NMEA buffer, which indicate

        * the position when last time. This function will validate

        * the index. If the buffer round back, then the index is 

        * invalidated. Next time client will receive the whole 

        * buffer. Note: This function shall be called before

        * FillPositionInfoL(). 

        * @param aNmeaIndex The NMEA buffer index.

        * @param aBottom Last time the client saw the bottom.

        */

        void ValidateNmeaBufferIndex(

            TInt& aNmeaIndex,

            TInt& aBottom) const;

        /**

        * Copy content of this

		* @param aFix the fix info that will be copied.

        */

        void operator =(const CBTGPSFix& aFix);

    private:  // Enumeration

		/**

        * Internal data class for satellite info

        */

        struct TSatelliteInfo

            {

            TInt iSatelliteId;

            TReal32 iElevation;

            TReal32 iAzimuth;

            TInt iSNR;

            };

        /**

        * GPS working mode

        */

        enum TGPSMode

            {

            EGpsModeSatellite=0, //GSP is using satellite to get fix

            EGpsModeEstimated,   //dead reckoning

            EGpsModeManualInput,

            EGpsModeSimulator,

            EGpsModeInvalid      //The fix is not valid

            };

        /**

        * GPS Quality Indicator

        */

        enum TGPSQuality

            {

            EGpsQualityNotValid = 0,

            EGpsQualitySPS      = 1,

            EGpsQualityDGPS     = 2,

            EGpsQualityPPS      = 3,

            EGpsQualityRTK      = 4,

            EGpsQualityFloatRTK = 5,

            EGpsQualityEstimated    = 6,

            EGpsQualityManualInput  = 7,

            EGpsQualitySimulation   = 8

            };

    private:  // New functions

        /**

        * Reset position parameters

        */

        void ResetPosition();

        /**

        * Parse message

        */

        void ParseMessageL(const TBTGPSNmeaParser& aParser);

        /**

        * Parse NMEA GGA Sentence

        */

        void ParseGGASentenceL(

            const TBTGPSNmeaParser& aParser);

        /**

        * Parse NMEA GSV Sentence

        */

        void ParseGSVSentenceL(

            const TBTGPSNmeaParser& aParser);

        /**

        * Parse NMEA GSA Sentence

        */

        void ParseGSASentenceL(

            const TBTGPSNmeaParser& aParser);

        /**

        * Parse NMEA RMC Sentence

        */

        void ParseRMCSentenceL(

            const TBTGPSNmeaParser& aParser);

        /**

        * Get latitude and longitude

        */

        void GetLatitudeLongitude(

            const TBTGPSNmeaParser& aParser,

            TInt aStartId);

        /**

        * Parses the degree information from the NMEA command 

        * (degrees and minutes) to

        * true degrees.

        * @return Error code

        */

        TInt GetDegrees(

            const TDesC8& aSide,

            const TDesC8& aDegreesMinutes,

            TReal64& aDegrees);

        /**

        * Appends the satellite data to the fix and quarantees 

        * that only KMaxNumberOfSatellites

        * are added.

        */

        void AppendSatelliteData(TSatelliteInfo& aSatInfo);

        /**

        * Extract satellite info from message parser

        */

        void ExtractSatInfoL(const TBTGPSNmeaParser& aParser);

        /**

        * Extracts the satellite data from a NMEA message and 

        * updates internal data variables.

        */

        void ExtractSatelliteDataL(

            const TBTGPSNmeaParser& aMessage,

            TInt aField1,

            TInt aField2,

            TInt aField3,

            TInt aField4);

        /**

        * Is used to copy the NMEA message and prevent panic if the 

        * NMEA message is too long.

        */

        TBool SecureCopy(TDes8& aTo,const TDesC8& aFrom);

    private: 

        /**

        * Defines the mask of received message

        */

        enum TReceivedMessage

            {

            EReceivedGSA = 0x01,

            EReceivedGGA = 0x02,

            EReceivedRMC = 0x04

            };

    private:    // Data

        //Current Fix data

        //Latitude, defaults to WGS-84 format.

        TReal64 iLatitude;

        //Longitude, defaults to WGS-84 format.

        TReal64 iLongitude;

        //Altitude, defaults to WGS-84 format.

        TReal32 iAltitude;

        //The timestamp of the fix

        TTime iTime;

        //Speed, defaults to WGS-84 format

        TReal32 iSpeed;

        //Heading, defaults to WGS-84 format

        TReal32 iHeading;

        //Number of satellites seen

        TInt iNumberOfSatellites;

        //Array of satellites

        TFixedArray<TSatelliteInfo,KMaxNumberOfSatellites> iSatelliteArray;

        //Satellites used in location calculation

        TInt iSatellitesUsed;

        //Array of used satellites

        TFixedArray<TInt,KMaxNumberOfSatellites> iUsedSatellitesArray;

        //Time received from satellites

       	TTime iSatelliteTime;

        //Horizontal dilution of precision

        TReal32 iHorizontalDoP;

        //Vertical dilution of precision

        TReal32 iVerticalDoP;

        //2D dilution of precision

        TReal32 iPositionDoP;

        //Geoidal Seperation

        TReal32 iGeoidalSeperation;

        // The fix validity

        TState iValid;

        //GPS Quality Indicator specified in GGA

        TGPSMode iGpsMode;

        //Received message mask

        TUint32 iReceivedMsgMask;

        //GSV sentence cache

        TBuf8<KMaxGSVLength> iNMEAGSVCache[KMaxGSVMessageNumber];

        //GSV total number of message

        TInt iGsvTotalNumberOfMessage;

        //GSV satellites in view

        TInt iGsvSatelliteInView;

        //The time that GSV sentences are fully retrieved.

        TTime iGsvTime;

        //NMEA Buffer. Not owned by this class

        CBTGPSNmeaBuffer* iNmeaBuffer;

    };

#endif 

// End of File