/* PSPP - computes sample statistics.
   Copyright (C) 1997-9, 2000, 2006 Free Software Foundation, Inc.
   Written by Ben Pfaff <blp@gnu.org>.

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License as
   published by the Free Software Foundation; either version 2 of the
   License, or (at your option) any later version.

   This program 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
   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., 51 Franklin Street, Fifth Floor, Boston, MA
   02110-1301, USA. */

#include <config.h>
#include <language/data-io/file-handle.h>
#include <libpspp/message.h>
#include <errno.h>
#include <stdlib.h>
#include <libpspp/alloc.h>
#include <data/file-name.h>
#include <language/command.h>
#include <language/lexer/lexer.h>
#include <language/line-buffer.h>
#include <libpspp/message.h>
#include <libpspp/magic.h>
#include <libpspp/str.h>
#include <data/variable.h>
#include <data/file-handle-def.h>

#include "gettext.h"
#define _(msgid) gettext (msgid)

/* (headers) */


/* (specification)
   "FILE HANDLE" (fh_):
     name=string;
     lrecl=integer;
     tabwidth=integer "x>=0" "%s must be nonnegative";
     mode=mode:!character/image/scratch.
*/
/* (declarations) */
/* (functions) */

int
cmd_file_handle (void)
{
  char handle_name[LONG_NAME_LEN + 1];
  struct fh_properties properties = *fh_default_properties ();

  struct cmd_file_handle cmd;
  struct file_handle *handle;

  if (!lex_force_id ())
    return CMD_CASCADING_FAILURE;
  str_copy_trunc (handle_name, sizeof handle_name, tokid);

  handle = fh_from_name (handle_name);
  if (handle != NULL)
    {
      msg (SE, _("File handle %s is already defined.  "
                 "Use CLOSE FILE HANDLE before redefining a file handle."),
	   handle_name);
      return CMD_CASCADING_FAILURE;
    }

  lex_get ();
  if (!lex_force_match ('/'))
    return CMD_CASCADING_FAILURE;

  if (!parse_file_handle (&cmd))
    return CMD_CASCADING_FAILURE;

  if (lex_end_of_command () != CMD_SUCCESS)
    goto lossage;

  if (cmd.s_name == NULL && cmd.mode != FH_SCRATCH)
    {
      lex_sbc_missing ("NAME");
      goto lossage;
    }

  switch (cmd.mode)
    {
    case FH_CHARACTER:
      properties.mode = FH_MODE_TEXT;
      if (cmd.sbc_tabwidth)
        properties.tab_width = cmd.n_tabwidth[0];
      break;
    case FH_IMAGE:
      properties.mode = FH_MODE_BINARY;
      if (cmd.n_lrecl[0] == NOT_LONG)
        msg (SE, _("Fixed-length records were specified on /RECFORM, but "
                   "record length was not specified on /LRECL.  "
                   "Assuming %d-character records."),
             properties.record_width);
      else if (cmd.n_lrecl[0] < 1)
        msg (SE, _("Record length (%ld) must be at least one byte.  "
                   "Assuming %d-character records."),
             cmd.n_lrecl[0], properties.record_width);
      else
        properties.record_width = cmd.n_lrecl[0];
      break;
    default:
      assert (0);
    }

  if (cmd.mode != FH_SCRATCH)
    fh_create_file (handle_name, cmd.s_name, &properties);
  else
    fh_create_scratch (handle_name);

  free_file_handle (&cmd);
  return CMD_SUCCESS;

 lossage:
  free_file_handle (&cmd);
  return CMD_CASCADING_FAILURE;
}

int
cmd_close_file_handle (void) 
{
  struct file_handle *handle;

  if (!lex_force_id ())
    return CMD_CASCADING_FAILURE;
  handle = fh_from_name (tokid);
  if (handle == NULL)
    return CMD_CASCADING_FAILURE;

  fh_free (handle);

  return CMD_SUCCESS;
}

/* Returns the name for REFERENT. */
static const char *
referent_name (enum fh_referent referent) 
{
  switch (referent) 
    {
    case FH_REF_FILE:
      return _("file");
    case FH_REF_INLINE:
      return _("inline file");
    case FH_REF_SCRATCH:
      return _("scratch file");
    default:
      abort ();
    }
}

/* Parses a file handle name, which may be a file name as a string
   or a file handle name as an identifier.  The allowed types of
   file handle are restricted to those in REFERENT_MASK.  Returns
   the file handle when successful, a null pointer on failure. */
struct file_handle *
fh_parse (enum fh_referent referent_mask)
{
  struct file_handle *handle;

  if (lex_match_id ("INLINE")) 
    handle = fh_inline_file ();
  else 
    {
      if (token != T_ID && token != T_STRING)
        {
          lex_error (_("expecting a file name or handle name"));
          return NULL;
        }

      handle = NULL;
      if (token == T_ID) 
        handle = fh_from_name (tokid);
      if (handle == NULL) 
        handle = fh_from_file_name (ds_c_str (&tokstr)); 
      if (handle == NULL)
        {
          if (token != T_ID || tokid[0] != '#' || get_syntax () != ENHANCED) 
            {
              char *file_name = ds_c_str (&tokstr);
              char *handle_name = xasprintf ("\"%s\"", file_name);
              handle = fh_create_file (handle_name, file_name,
                                       fh_default_properties ());
              free (handle_name);
            }
          else
            handle = fh_create_scratch (tokid);
        }
      lex_get ();
    }

  if (!(fh_get_referent (handle) & referent_mask)) 
    {
      msg (SE, _("Handle for %s not allowed here."),
           referent_name (fh_get_referent (handle)));
      return NULL;
    }

  return handle;
}

/*
   Local variables:
   mode: c
   End:
*/