#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <ctype.h>

/* The following include file must define a function 'isnan' */

/* This function, which returns '1' if the number is NaN and 0*/

/* otherwise, could be hand-written if not available. */

/* Comment out one of the two following lines, as applicable */

#include <math.h>               /* for gcc */

/* #include <mathimf.h>            /\* for Intel icc *\/ */

#define NaN log(-1.0)

#define IEXT 0

#define FALSE 0

#define TRUE 1                  /* constants */

#define RECL 81

#define MAXINBUFF RECL+14

/** Max size of in buffer **/

#define MAXREAD MAXINBUFF-2

/** Max to read 2 less than total size (just to be safe) **/

#define MAXMOD 30

/** Max number of models in a file **/

#define PATH MAXREAD

/** Max path and filename length **/

#define EXT_COEFF1 (double)0

#define EXT_COEFF2 (double)0

#define EXT_COEFF3 (double)0

#define MAXDEG 13

#define MAXCOEFF (MAXDEG*(MAXDEG+2)+1)

                /* index starts with 1!, (from old Fortran) */

#define RECLEN 80 /* characters excluding line ending(s) */

#define MAXMODNAMELENGTH 8

                /* e.g. IGRF2005 */

struct model_t{

    char name[MAXMODNAMELENGTH + 1];

    double epoch;

    int max1;

    int max2;

    int max3;

    double yrmin;

    double yrmax;

    double altmin;

    double altmax;

    double gh[MAXCOEFF];  /* first pair of coeffients */

    double ghr[MAXCOEFF]; /* second pair; usually 0; rates of change */

    struct model_t *next;

};

/*  Subroutines used  */

void print_dashed_line();

void print_long_dashed_line(void);

void print_header();

void print_result(double date, double d, double i, double h, double x, double y, double z, double f);

void print_header_sv();

void print_result_sv(double date, double ddot, double idot, double hdot, double xdot, double ydot, double zdot, double fdot);

void print_result_file(FILE *outf, double d, double i, double h, double x, double y, double z, double f,

                       double ddot, double idot, double hdot, double xdot, double ydot, double zdot, double fdot);

double degrees_to_decimal(int degrees,int minutes,int seconds);

double julday(int i_month, int i_day, int i_year);

int interpsh(double date, double dte1, int nmax1, double dte2, double nmax2,

                double *gh_Schmidt1, double *gh_Schmidt2, double *gh_model);

int extrapsh(double date, double dte1, int nmax1, int nmax2,

                double *gh_Schmidt1, double *gh_Schmidt2, double *gh_model);

void shval3(int igdgc, double flat, double flon, double elev,

                int nmax, double *gh, int iext,

                double ext1, double ext2, double ext3,

                double *x_ptr, double *y_ptr, double *z_ptr);

int   safegets(char *buffer,int n);

int getshc(char *file, int iflag, long strec, int nmax_of_gh,

                    double *gh_Schmidt);

void dihf(double x, double y, double z,

                 double *d_ptr, double *i_ptr, double *h_ptr, double *f_ptr);

int models_from_lines(struct model_t ***model_array);

int models_from_file(char *filename, struct model_t ***model_array);

void free_models(struct model_t **model_array, int nmodels);

int dihf_from_models(struct model_t **model_array, int nmodels,

                        double yr, double lon, double lat,

                        double *d_ptr, double *i_ptr, double *h_ptr,

                        double *f_ptr);