/*  $Id$

    Part of SWI-Prolog

    Author:        Jan Wielemaker
    E-mail:        jan@swi.psy.uva.nl
    WWW:           http://www.swi-prolog.org
    Copyright (C): 1985-2002, University of Amsterdam

    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 2.1 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 Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
*/

#include <SWI-Prolog.h>
#include <stdio.h>
#include <string.h>

#define MAXLINE 10240

static int
substr(const char *in, const char *sub)
{ int ls = strlen(sub);
  int l = strlen(in) - ls;

  for( ; l >= 0; in++, l-- )
  { if ( strncmp(in, sub, ls) == 0 )
      return 1;
  }

  return 0;
}


static foreign_t
pl_get_ps_parameters(term_t file, term_t iseps, term_t bb)
{ char *fname;
  FILE *fd;

  if ( !PL_get_chars(file, &fname, CVT_ALL) )
    return PL_warning("get_ps_parameters/3: invalid filename");

  if ( (fd = fopen(fname, "r")) )
  { char buf[MAXLINE];
    char *s;

    if ( (s=fgets(buf, sizeof(buf), fd)) )
    { int rc;

      if ( substr(s, "EPSF") )
	rc = PL_unify_atom_chars(iseps, "eps");
      else
	rc = PL_unify_atom_chars(iseps, "ps");

      if ( !rc )
	return rc;
    }

    do
    { double a1, a2, a3, a4;

      if ( sscanf(buf, "%%%%BoundingBox: %lf %lf %lf %lf", &a1, &a2, &a3, &a4) == 4 )
      { fclose(fd);
	return PL_unify_term(bb,
			     PL_FUNCTOR, PL_new_functor(PL_new_atom("bb"), 4),
			     PL_FLOAT, a1,
			     PL_FLOAT, a2,
			     PL_FLOAT, a3,
			     PL_FLOAT, a4);
      }
    } while( (s=fgets(buf, sizeof(buf), fd)) );

    fclose(fd);
    PL_warning("get_ps_parameters/3: could not find %%%%BoundingBox in %s",
	       fname);

    PL_fail;
  }

  PL_warning("get_ps_parameters/3: could not open %s", fname);
  PL_fail;
}


void
install_ps()
{ PL_register_foreign("get_ps_parameters", 3, pl_get_ps_parameters, 0);
}