# include <stdio.h>
# include <hstio.h>
# include "../stiserr.h"

/* This routine gets the exposure time and the time of the middle of
   the exposure from an extension header.

   Phil Hodge, 1998 Oct 5:
	Change status value 1001 to GENERIC_ERROR_CODE.
*/

int GetTimes11 (Hdr *hdr, double *exptime, double *midpt) {

/* arguments:
Hdr *hdr         i: header of current imset
double *exptime  o: the exposure time (sec)
double *midpt    o: the time (MJD) of the middle of the exposure
*/

	int status;

	double expstart, expend;
	int use_def = 0;		/* missing keyword is fatal error */

	int Get_KeyD (Hdr *, char *, int, double, double *);

	if (status = Get_KeyD (hdr, "EXPTIME", use_def, 0., exptime))
	    return (status);
	if (*exptime < 0.) {
	    printf ("ERROR    Exposure time = %.6g is invalid.\n",
		*exptime);
	    return (GENERIC_ERROR_CODE);
	}

	if (status = Get_KeyD (hdr, "EXPSTART", use_def, 0., &expstart))
	    return (status);
	if (status = Get_KeyD (hdr, "EXPEND", use_def, 0., &expend))
	    return (status);

	*midpt = (expstart + expend) / 2.;

	return (0);
}