/* Copyright (C) 2001 Free Software Foundation, Inc.
 * 
 * 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
 */

#if HAVE_CONFIG_H
#  include <config.h>
#endif

#include <string.h>
#include "_scm.h"
#include "vm-bootstrap.h"
#include "instructions.h"
#include "modules.h"
#include "programs.h"
#include "procprop.h" // scm_sym_name
#include "srcprop.h" // scm_sym_filename
#include "vm.h"


scm_t_bits scm_tc16_program;

static SCM write_program = SCM_BOOL_F;

SCM_DEFINE (scm_make_program, "make-program", 1, 2, 0,
	    (SCM objcode, SCM objtable, SCM external),
	    "")
#define FUNC_NAME s_scm_make_program
{
  SCM_VALIDATE_OBJCODE (1, objcode);
  if (SCM_UNLIKELY (SCM_UNBNDP (objtable)))
    objtable = SCM_BOOL_F;
  else if (scm_is_true (objtable))
    SCM_VALIDATE_VECTOR (2, objtable);
  if (SCM_UNLIKELY (SCM_UNBNDP (external)))
    external = SCM_EOL;
  else
    /* FIXME: currently this test is quite expensive (can be 2-3% of total
       execution time in programs that make many closures). We could remove it,
       yes, but we'd get much better gains if we used some other method, like
       just capturing the variables that we need instead of all heap-allocated
       variables. Dunno. Keeping the check for now, as it's a user-callable
       function, and inlining the op in the vm's make-closure operation. */
    SCM_VALIDATE_LIST (3, external);

  SCM_RETURN_NEWSMOB3 (scm_tc16_program, objcode, objtable, external);
}
#undef FUNC_NAME

static SCM
program_mark (SCM obj)
{
  if (scm_is_true (SCM_PROGRAM_OBJTABLE (obj)))
    scm_gc_mark (SCM_PROGRAM_OBJTABLE (obj));
  if (!scm_is_null (SCM_PROGRAM_EXTERNALS (obj)))
    scm_gc_mark (SCM_PROGRAM_EXTERNALS (obj));
  return SCM_PROGRAM_OBJCODE (obj);
}

static SCM
program_apply (SCM program, SCM args)
{
  return scm_vm_apply (scm_the_vm (), program, args);
}

static SCM
program_apply_0 (SCM program)
{
  return scm_c_vm_run (scm_the_vm (), program, NULL, 0);
}

static SCM
program_apply_1 (SCM program, SCM a)
{
  return scm_c_vm_run (scm_the_vm (), program, &a, 1);
}

static SCM
program_apply_2 (SCM program, SCM a, SCM b)
{
  SCM args[2];
  args[0] = a;
  args[1] = b;
  return scm_c_vm_run (scm_the_vm (), program, args, 2);
}

static int
program_print (SCM program, SCM port, scm_print_state *pstate)
{
  static int print_error = 0;

  if (SCM_FALSEP (write_program) && scm_module_system_booted_p)
    write_program = scm_module_local_variable
      (scm_c_resolve_module ("system vm program"),
       scm_from_locale_symbol ("write-program"));
  
  if (SCM_FALSEP (write_program) || print_error)
    return scm_smob_print (program, port, pstate);

  print_error = 1;
  scm_call_2 (SCM_VARIABLE_REF (write_program), program, port);
  print_error = 0;
  return 1;
}


/*
 * Scheme interface
 */

SCM_DEFINE (scm_program_p, "program?", 1, 0, 0,
	    (SCM obj),
	    "")
#define FUNC_NAME s_scm_program_p
{
  return SCM_BOOL (SCM_PROGRAM_P (obj));
}
#undef FUNC_NAME

SCM_DEFINE (scm_program_base, "program-base", 1, 0, 0,
	    (SCM program),
	    "")
#define FUNC_NAME s_scm_program_base
{
  SCM_VALIDATE_PROGRAM (1, program);

  return scm_from_ulong ((unsigned long) SCM_PROGRAM_DATA (program)->base);
}
#undef FUNC_NAME

SCM_DEFINE (scm_program_arity, "program-arity", 1, 0, 0,
	    (SCM program),
	    "")
#define FUNC_NAME s_scm_program_arity
{
  struct scm_objcode *p;

  SCM_VALIDATE_PROGRAM (1, program);

  p = SCM_PROGRAM_DATA (program);
  return scm_list_4 (SCM_I_MAKINUM (p->nargs),
		     SCM_I_MAKINUM (p->nrest),
		     SCM_I_MAKINUM (p->nlocs),
		     SCM_I_MAKINUM (p->nexts));
}
#undef FUNC_NAME

SCM_DEFINE (scm_program_objects, "program-objects", 1, 0, 0,
	    (SCM program),
	    "")
#define FUNC_NAME s_scm_program_objects
{
  SCM_VALIDATE_PROGRAM (1, program);
  return SCM_PROGRAM_OBJTABLE (program);
}
#undef FUNC_NAME

SCM_DEFINE (scm_program_module, "program-module", 1, 0, 0,
	    (SCM program),
	    "")
#define FUNC_NAME s_scm_program_module
{
  SCM objs;
  SCM_VALIDATE_PROGRAM (1, program);
  objs = SCM_PROGRAM_OBJTABLE (program);
  return scm_is_true (objs) ? scm_c_vector_ref (objs, 0) : SCM_BOOL_F;
}
#undef FUNC_NAME

SCM_DEFINE (scm_program_meta, "program-meta", 1, 0, 0,
	    (SCM program),
	    "")
#define FUNC_NAME s_scm_program_meta
{
  SCM metaobj;
  
  SCM_VALIDATE_PROGRAM (1, program);

  metaobj = scm_objcode_meta (SCM_PROGRAM_OBJCODE (program));
  if (scm_is_true (metaobj))
    return scm_make_program (metaobj, SCM_BOOL_F, SCM_EOL);
  else
    return SCM_BOOL_F;
}
#undef FUNC_NAME

SCM_DEFINE (scm_program_bindings, "program-bindings", 1, 0, 0,
	    (SCM program),
	    "")
#define FUNC_NAME s_scm_program_bindings
{
  SCM meta;
  
  SCM_VALIDATE_PROGRAM (1, program);

  meta = scm_program_meta (program);
  if (scm_is_false (meta))
    return SCM_BOOL_F;
  
  return scm_car (scm_call_0 (meta));
}
#undef FUNC_NAME

SCM_DEFINE (scm_program_sources, "program-sources", 1, 0, 0,
	    (SCM program),
	    "")
#define FUNC_NAME s_scm_program_sources
{
  SCM meta, sources, ret, filename;
  
  SCM_VALIDATE_PROGRAM (1, program);

  meta = scm_program_meta (program);
  if (scm_is_false (meta))
    return SCM_EOL;
  
  filename = SCM_BOOL_F;
  ret = SCM_EOL;
  for (sources = scm_cadr (scm_call_0 (meta)); !scm_is_null (sources);
       sources = scm_cdr (sources))
    {
      SCM x = scm_car (sources);
      if (scm_is_pair (x))
        {
          if (scm_is_number (scm_car (x)))
            {
              SCM addr = scm_car (x);
              ret = scm_acons (addr, scm_cons (filename, scm_cdr (x)),
                               ret);
            }
          else if (scm_is_eq (scm_car (x), scm_sym_filename))
            filename = scm_cdr (x);
        }
    }
  return scm_reverse_x (ret, SCM_UNDEFINED);
}
#undef FUNC_NAME

SCM_DEFINE (scm_program_properties, "program-properties", 1, 0, 0,
	    (SCM program),
	    "")
#define FUNC_NAME s_scm_program_properties
{
  SCM meta;
  
  SCM_VALIDATE_PROGRAM (1, program);

  meta = scm_program_meta (program);
  if (scm_is_false (meta))
    return SCM_EOL;
  
  return scm_cddr (scm_call_0 (meta));
}
#undef FUNC_NAME

SCM_DEFINE (scm_program_name, "program-name", 1, 0, 0,
	    (SCM program),
	    "")
#define FUNC_NAME s_scm_program_name
{
  SCM_VALIDATE_PROGRAM (1, program);
  return scm_assq_ref (scm_program_properties (program), scm_sym_name);
}
#undef FUNC_NAME

SCM_DEFINE (scm_program_source, "program-source", 2, 0, 0,
	    (SCM program, SCM ip),
	    "")
#define FUNC_NAME s_scm_program_source
{
  SCM_VALIDATE_PROGRAM (1, program);
  return scm_c_program_source (program, scm_to_size_t (ip));
}
#undef FUNC_NAME
    
extern SCM
scm_c_program_source (SCM program, size_t ip)
{
  SCM sources, source = SCM_BOOL_F;

  for (sources = scm_program_sources (program);
       !scm_is_null (sources)
         && scm_to_size_t (scm_caar (sources)) <= ip;
       sources = scm_cdr (sources))
    source = scm_car (sources);
  
  return source; /* (addr . (filename . (line . column))) */
}

SCM_DEFINE (scm_program_external, "program-external", 1, 0, 0,
	    (SCM program),
	    "")
#define FUNC_NAME s_scm_program_external
{
  SCM_VALIDATE_PROGRAM (1, program);
  return SCM_PROGRAM_EXTERNALS (program);
}
#undef FUNC_NAME

SCM_DEFINE (scm_program_external_set_x, "program-external-set!", 2, 0, 0,
	    (SCM program, SCM external),
	    "Modify the list of closure variables of @var{program} (for "
	    "debugging purposes).")
#define FUNC_NAME s_scm_program_external_set_x
{
  SCM_VALIDATE_PROGRAM (1, program);
  SCM_VALIDATE_LIST (2, external);
  SCM_PROGRAM_EXTERNALS (program) = external;
  return SCM_UNSPECIFIED;
}
#undef FUNC_NAME

SCM_DEFINE (scm_program_objcode, "program-objcode", 1, 0, 0,
	    (SCM program),
	    "Return a @var{program}'s object code.")
#define FUNC_NAME s_scm_program_objcode
{
  SCM_VALIDATE_PROGRAM (1, program);

  return SCM_PROGRAM_OBJCODE (program);
}
#undef FUNC_NAME



void
scm_bootstrap_programs (void)
{
  scm_tc16_program = scm_make_smob_type ("program", 0);
  scm_set_smob_mark (scm_tc16_program, program_mark);
  scm_set_smob_apply (scm_tc16_program, program_apply, 0, 0, 1);
  scm_smobs[SCM_TC2SMOBNUM (scm_tc16_program)].apply_0 = program_apply_0;
  scm_smobs[SCM_TC2SMOBNUM (scm_tc16_program)].apply_1 = program_apply_1;
  scm_smobs[SCM_TC2SMOBNUM (scm_tc16_program)].apply_2 = program_apply_2;
  scm_set_smob_print (scm_tc16_program, program_print);
  scm_c_register_extension ("libguile", "scm_init_programs",
                            (scm_t_extension_init_func)scm_init_programs, NULL);
}

void
scm_init_programs (void)
{
  scm_bootstrap_vm ();
  
#ifndef SCM_MAGIC_SNARFER
#include "libguile/programs.x"
#endif
}

/*
  Local Variables:
  c-file-style: "gnu"
  End:
*/