/*
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2 of the License, or (at your option) any later version.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *  
 *  Copyright (C) 2000 - 2005 Liam Girdwood  
 */

#ifndef _LN_SOLAR_H
#define _LN_SOLAR_H

#include <libnova/ln_types.h>

#define LN_SOLAR_STANDART_HORIZON              -0.8333
#define LN_SOLAR_CIVIL_HORIZON                 -6.0
#define LN_SOLAR_NAUTIC_HORIZON                -12.0 
#define LN_SOLAR_ASTRONOMICAL_HORIZON          -18.0

#ifdef __cplusplus
extern "C" {
#endif

/*! \defgroup solar Solar
*
* Calculate solar ecliptical/equatorial coordinates for a given julian date.  
* Accuracy 0.01 arc second error - uses VSOP87 solution. 
*
* All angles are expressed in degrees.
*/

/*! \fn int ln_get_solar_rst_horizon (double JD, struct ln_lnlat_posn * observer, double horizon, struct ln_rst_time *rst);
* \brief Return solar rise/set time over local horizon (specified in degrees).
*  \ingroup solar
*/
int LIBNOVA_EXPORT ln_get_solar_rst_horizon (double JD, struct ln_lnlat_posn * observer, double horizon, struct ln_rst_time * rst);

/*! \fn int ln_get_solar_rst (double JD, struct ln_lnlat_posn * observer, struct ln_rst_time * rst);
* \brief Calculate the time of rise, set and transit for the Sun.
* \ingroup solar
*/
int LIBNOVA_EXPORT ln_get_solar_rst (double JD, struct ln_lnlat_posn * observer, struct ln_rst_time * rst);
	
/*! \fn void ln_get_solar_geom_coords (double JD, struct ln_helio_posn * position);
* \brief Calculate solar geometric coordinates. 
* \ingroup solar 
*/
void LIBNOVA_EXPORT ln_get_solar_geom_coords (double JD, struct ln_helio_posn * position);

/*! \fn void ln_get_solar_equ_coords (double JD, struct ln_equ_posn * position);
* \brief Calculate apparent equatorial coordinates.
* \ingroup solar
*/ 
void LIBNOVA_EXPORT ln_get_solar_equ_coords (double JD, struct ln_equ_posn * position);

/*! \fn void ln_get_solar_ecl_coords (double JD, struct ln_lnlat_posn * position);
* \brief Calculate apparent ecliptical coordinates.
* \ingroup solar
*/ 
void LIBNOVA_EXPORT ln_get_solar_ecl_coords (double JD, struct ln_lnlat_posn * position);

/*! \fn void ln_get_solar_geo_coords (double JD, struct ln_rect_posn * position)
* \brief Calculate geocentric coordinates (rectangular)
* \ingroup solar
*/
void LIBNOVA_EXPORT ln_get_solar_geo_coords (double JD, struct ln_rect_posn * position);
	
/*! \fn double ln_get_solar_sdiam (double JD)
* \brief Calculate the semidiameter of the Sun in arc seconds.
* \ingroup solar
*/
double LIBNOVA_EXPORT ln_get_solar_sdiam (double JD);

#ifdef __cplusplus
};
#endif

#endif
