/******************************************************************************
 * $Id: msg_basic_types.h 10645 2007-01-18 02:22:39Z warmerdam $
 *
 * Project:  MSG Native Reader
 * Purpose:  Basic types implementation.
 * Author:   Frans van den Bergh, fvdbergh@csir.co.za
 *
 ******************************************************************************
 * Copyright (c) 2005, Frans van den Bergh <fvdbergh@csir.co.za>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 ****************************************************************************/

#ifndef MSG_BASIC_TYPES
#define MSG_BASIC_TYPES

#include <math.h>

#ifndef M_PI
#define M_PI  3.1415926535897932384626433832795
#endif

namespace msg_native_format {

const unsigned int      SATELLITESTATUS_RECORD_LENGTH   = 60134;
const unsigned int      IMAGEACQUISITION_RECORD_LENGTH  = 700;
const unsigned int      CELESTIALEVENTS_RECORD_LENGTH   = 326058; // should be 56258 according to ICD105 ??
const unsigned int      IMAGEDESCRIPTION_RECORD_LENGTH  = 101;

const unsigned int      RADIOMETRICPROCESSING_RECORD_OFFSET = 
    SATELLITESTATUS_RECORD_LENGTH + 
    IMAGEACQUISITION_RECORD_LENGTH + 
    CELESTIALEVENTS_RECORD_LENGTH +
    IMAGEDESCRIPTION_RECORD_LENGTH;

typedef int             INTEGER;                    // 32 bits
typedef unsigned int    UNSIGNED;                   // 32 bits
typedef unsigned short  USHORT;                     // 16 bits
typedef unsigned char   TIME_CDS_SHORT[6];
typedef unsigned char   TIME_CDS_EXPANDED[10];
typedef unsigned char   EBYTE;                      // enumerated byte
typedef unsigned char   UBYTE;                      // enumerated byte
typedef float           REAL;

typedef unsigned short int  GP_SC_ID;         // 16 bits, enumerated
typedef unsigned char       GP_SC_CHAN_ID;    // 8 bits,  enumerated
typedef unsigned char       GP_FAC_ID;        // 8 bits,  enumerated
typedef unsigned char       GP_FAC_ENV;       // 8 bits,  enumerated
typedef unsigned int        GP_SU_ID;         // 32 bits, interval partition
typedef unsigned char       GP_SVCE_TYPE;     // 8 bits, enumerated

// all structures must be packed on byte boundaries
#pragma pack(1)

typedef struct {
    unsigned char qualifier1;
    unsigned char qualifier2;
    unsigned char qualifier3;
    unsigned char qualifier4;
} GP_CPU_ID;

typedef struct {
    char name[30];
    char value[50];
} PH_DATA;

typedef struct {
    char name[30];
    char size[16];
    char address[16];
} PH_DATA_ID;

typedef struct {
    PH_DATA     formatName;
    PH_DATA     formatDocumentName;
    PH_DATA     formatDocumentMajorVersion;
    PH_DATA     formatDocumentMinorVersion;
    PH_DATA     creationDateTime;
    PH_DATA     creatingCentre;
    PH_DATA_ID  dataSetIdentification[5];
    UBYTE       slack[1364];                // what is this? This is not in the documentation?
    PH_DATA     totalFileSize;
    PH_DATA     gort;
    PH_DATA     asti;
    PH_DATA     llos;
    PH_DATA     snit;
    PH_DATA     aiid;
    PH_DATA     ssbt;
    PH_DATA     ssst;
    PH_DATA     rrcc;
    PH_DATA     rrbt;
    PH_DATA     rrst;
    PH_DATA     pprc;
    PH_DATA     ppdt;
    PH_DATA     gplv;
    PH_DATA     apnm;
    PH_DATA     aarf;
    PH_DATA     uudt;
    PH_DATA     qqov;
    PH_DATA     udsp;
} MAIN_PROD_HEADER;

typedef struct {
    PH_DATA     abid;
    PH_DATA     smod;
    PH_DATA     apxs;
    PH_DATA     avpa;
    PH_DATA     lscd;
    PH_DATA     lmap;
    PH_DATA     qdlc;
    PH_DATA     qdlp;
    PH_DATA     qqai;
    PH_DATA     selectedBandIds;
    PH_DATA     southLineSelectedRectangle;
    PH_DATA     northLineSelectedRectangle;
    PH_DATA     eastColumnSelectedRectangle;
    PH_DATA     westColumnSelectedRectangle;
} SECONDARY_PROD_HEADER;

typedef struct {
    UBYTE       visirlineVersion;
    GP_SC_ID    satelliteId;
    TIME_CDS_EXPANDED   trueRepeatCycleStart;
    INTEGER     lineNumberInVisirGrid;
    GP_SC_CHAN_ID   channelId;
    TIME_CDS_SHORT  l10LineMeanAcquisitionTime;
    EBYTE       lineValidity;
    EBYTE       lineRadiometricQuality;
    EBYTE       lineGeometricQuality;
    // actual line data not represented here
} SUB_VISIRLINE;

typedef struct {
    UBYTE       headerVersionNo;
    EBYTE       packetType;         // 2 = mission data 
    EBYTE       subHeaderType;      // 0 = no subheader, 1 = GP_PK_SH1, 2 = GP_PK_SH2
    GP_FAC_ID   sourceFacilityId;
    GP_FAC_ENV  sourceEnvId;
    UBYTE       sourceInstanceId;
    GP_SU_ID    sourceSUId;
    GP_CPU_ID   sourceCPUId;
    GP_FAC_ID   destFacilityId;
    GP_FAC_ENV  destEnvId;
    USHORT      sequenceCount;
    UNSIGNED    packetLength;      
} GP_PK_HEADER;

typedef struct {
    UBYTE       subHeaderVersionNo;
    EBYTE       checksumFlag;
    UBYTE       acknowledgement[4];
    GP_SVCE_TYPE    serviceType;
    UBYTE       serviceSubType;
    TIME_CDS_SHORT  packetTime;
    GP_SC_ID    spacecraftId;
} GP_PK_SH1;

typedef struct {
    double  cal_slope;
    double  cal_offset;
} CALIBRATION; 

typedef struct {
    EBYTE       radianceLinearisation[12];
    EBYTE       detectorEqualisation[12];
    EBYTE       onboardCalibrationResult[12];
    EBYTE       MPEFCalFeedback[12];
    EBYTE       MTFAdaption[12];
    EBYTE       straylightCorrectionFlag[12];
    CALIBRATION level1_5ImageCalibration[12];
    // rest of structure omitted for now
} RADIOMETRIC_PROCCESSING_RECORD;

typedef struct {
    INTEGER     numberOfLines;
    INTEGER     numberOfColumns;
    REAL        lineDirGridStep;
    REAL        columnDirGridStep;
    EBYTE       gridOrigin;
} REFERENCEGRID_VISIR;

typedef struct {
    EBYTE       typeOfProjection;
    REAL        longitudeOfSSP;
    REFERENCEGRID_VISIR referencegrid_visir;
    // rest of record omitted, for now
} IMAGE_DESCRIPTION_RECORD;

// disable byte-packing 
#pragma pack()

// endian conversion routines
void to_native(GP_PK_HEADER& h);
void to_native(GP_PK_SH1& h);
void to_native(SUB_VISIRLINE& v);
void to_native(RADIOMETRIC_PROCCESSING_RECORD& r);
void to_native(IMAGE_DESCRIPTION_RECORD& r);

// utility function, alters string fields permanently
void to_string(PH_DATA& d);

// unit tests on structures, returns true on success
bool perform_type_size_check(void);

class Conversions {
public:
    static void convert_pixel_to_geo(double line, double column, double& longitude, double& latitude);
    static void convert_geo_to_pixel(double longitude, double latitude, unsigned int& line, unsigned int& column);
    
    static void compute_pixel_xyz(double line, double column, double& x, double& y, double& z);
    static double compute_pixel_area_sqkm(double line, double column);

    static const double altitude;   // from origin
    static const double req;        // earth equatorial radius
    static const double rpol;       // earth polar radius
    static const double oblate;     // oblateness of earth
    static const double deg_to_rad; 
    static const double rad_to_deg; 
    static const double step;       // pixel / line step in degrees
    static const double nlines;     // number of lines in an image
    
    static const int CFAC;     // Column scale factor
    static const int LFAC;     // Line scale factor
    static const int COFF;     // Column offset
    static const int LOFF;     // Line offset
    
};

} // msg_native_format

#endif