#include "fget_coord.h"


/***************************************************************************\
*                                                                           *
*   Module Name:        fget_coord                                          *
*                                                                           *
*   Programmer:         Jan C. Depner                                       *
*                                                                           *
*   Date Written:       July 2000                                           *
*                                                                           *
*   Module Security                                                         *
*   Classification:     Unclassified                                        *
*                                                                           *
*   Data Security                                                           *
*   Classification:     Unknown                                             *
*                                                                           *
*   Purpose:            Gets a pair of geographic coordinates from a file.  *
*                                                                           *
*   Inputs:             lat_hemi            -   latitude hemisphere         *
*                                               indicator (S or N)          *
*                       lat_deg             -   latitude degrees            *
*                       lat_min             -   latitude minutes            *
*                       lat_sec             -   latitude seconds            *
*                       lon_hemi            -   longitude hemisphere        *
*                                               indicator (S or N)          *
*                       lon_deg             -   longitude degrees           *
*                       lon_min             -   longitude minutes           *
*                       lon_sec             -   longitude seconds           *
*                                                                           *
*   Outputs:            NV_BOOL             -   False if end of file        *
*                                                                           *
*   Restrictions:       Geographic positions are entered as a lat, lon pair *
*                       separated by a comma.  A lat or lon may be in any   *
*                       of the following formats (degrees, minutes, and     *
*                       seconds must be separated by a space or tab) :      *
*                                                                           *
*                           Degrees decimal                 : S 28.4532     *
*                           Degrees minutes decimal         : S 28 27.192   *
*                           Degrees minutes seconds decimal : S 28 27 11.52 *
*                                                                           *
*                       Hemisphere may be indicated by letter or by sign.   *
*                       West longitude and south latitude are negative :    *
*                                                                           *
*                           Ex. : -28 27 11.52 = S28 27 11.52 = s 28 27.192 *
*                                                                           *
\***************************************************************************/

NV_BOOL fget_coord (FILE *fp, NV_CHAR *lat_hemi, NV_INT32 *lat_deg, NV_INT32 *lat_min,
                    NV_FLOAT32 *lat_sec, NV_CHAR *lon_hemi, NV_INT32 *lon_deg, NV_INT32 *lon_min,
                    NV_FLOAT32 *lon_sec)
{
  NV_INT32    i, j, sign;
  NV_CHAR     string[60], lat[30], lon[30];
  NV_FLOAT64  f1, f2, f3, fdeg, fmin, fsec;


  /*  Get the coordinates and make sure there is a comma between the  */
  /*  lat and lon.                                                    */

  do
    {
      if (fgets (string, sizeof (string), fp) == NULL) return (NVFalse);
    } while (strstr (string, ",") == NULL);


  /*  Break the input into a lat and lon string.                      */
    
  j = strcspn (string, ",");

  strncpy (lat, string, j);
  lat[j] = 0;

  strcpy (lon, (strstr (string, ",") + 1 ));


  /*  Handle the latitude (j = 0) and longitude (j = 1) portions of   */
  /*  the input string.                                               */
    
  for (j = 0 ; j < 2 ; j++)
    {
      if (j)
        {
          strcpy (string, lon);
        }
      else
        {
          strcpy (string, lat);
        }

      sign = 0;

      /*  Check for and clear sign or hemisphere indicators.          */
        
      for (i = 0 ; i < (NV_INT32) strlen (string) ; i++)
        {
          if (j)
            {
              if (string[i] == 'W' || string[i] == 'w' || string[i] == '-')
                {
                  string[i] = ' ';
                  sign = 1;
                }
            }
          else
            {
              if (string[i] == 'S' || string[i] == 's' || string[i] == '-')
                {
                  string[i] = ' ';
                  sign = 1;
                }
            }

          if (string[i] == 'n' || string[i] == 'N' || string[i] == 'e' ||
              string[i] == 'E' || string[i] == '+') string[i] = ' ';
        }
    
      fdeg = 0.0;
      fmin = 0.0;
      fsec = 0.0;
      f1 = 0.0;
      f2 = 0.0;
      f3 = 0.0;


      /*  Convert the string to degrees, minutes, and seconds.        */
        
      i = sscanf (string, "%lf %lf %lf", &f1, &f2, &f3);


      /*  Based on the number of values scanned, compute the total    */
      /*  degrees.                                                    */
        
      switch (i)
        {
        case 3:
          fsec = f3 / 3600.0;
    
        case 2:
          fmin = f2 / 60.0;
    
        case 1:
          fdeg = f1;
        }

      fdeg += fmin + fsec;


      /*  Get the sign and load the lat or lon values.                */
        
      if (j)
        {
          if (sign)
            {
              *lon_hemi = 'W';
            }
          else
            {
              *lon_hemi = 'E';
            }

          *lon_deg = (NV_INT32) fdeg;
          fmin = (fdeg - *lon_deg) * 60.0;
          *lon_min = (NV_INT32) (fmin + 0.00001);
          *lon_sec = (fmin - *lon_min) * 60.0 + 0.00001;
        }
      else
        {
          if (sign)
            {
              *lat_hemi = 'S';
            }
          else
            {
              *lat_hemi = 'N';
            }
            
          *lat_deg = (NV_INT32) fdeg;
          fmin = (fdeg - *lat_deg) * 60.0;
          *lat_min = (NV_INT32) (fmin + 0.00001);
          *lat_sec = (fmin - *lat_min) * 60.0 + 0.00001;
        }
    }

  return (NVTrue);
}