/*
 * Copyright (c) 1995, 1996 Gunther Schadow.  All rights reserved.
 *
 * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#ifndef PG_XIOS_H_
#define PG_XIOS_H_

#include <pg_config.h>

#pragma interface

#include "Delimiters.h"

#ifdef WITH_XDR
# include "Xdr.h"
#endif

/*
 * The encoding of the `null value'. Note the distinction between
 * a null value and a value which is not present. 
 */
#define NULLVAL "\"\""

/*
 * How to print special symbols to the debug stream 
 */
#ifndef DS_STYLE
#define DS_STYLE 1
#endif

#if DS_STYLE == 1
#  define DSNULL   "nil"
#  define DSNOPS   ""
#  define DSVOID   "void"
#  define DSBGR0   "("
#  define DSBGR1   ""
#  define DSFRST   " "
#  define DSSEPR   " "
#  define DSEGRP   ")\n"
#  define DSBQUO   "\""
#  define DSEQUO   "\""
#elif DS_STYLE == 2
#  define DSNULL   "<null>"
#  define DSNOPS   "<nil>"
#  define DSVOID   "<void>"
#  define DSBGR0   "["      
#  define DSBGR1   "] {"
#  define DSFRST   "<1st>"
#  define DSSEPR   ", "
#  define DSEGRP   "}"
#  define DSBQUO   "`"
#  define DSEQUO   "\'"
#elif DS_STYLE 3
#  define DSNULL   "null;"
#  define DSNOPS   "nil;"
#  define DSVOID   "void;"
#  define DSBGR0   "*"      
#  define DSBGR1   "() {"
#  define DSFRST   "first;"
#  define DSSEPR   "; "
#  define DSEGRP   "; }"
#  define DSBQUO   "\""
#  define DSEQUO   "\""
#else
#  error illegal DS_STYLE
#endif

/* 
 * We extend the fstream class by a set of flags which tell the
 * I/O mode in use. Currently we have the following coding modes:  
 *
 *   1.) HL7 Encoding Rules as described in the HL7 standard
 *   2.) ASTM Encoding Rules
 *   3.) debug mode used to generate human readable output
 *   4.) XDR (RFC 1014)
 *
 * Even though these flags are mutually exclusive, we define
 * them as seperate flags just in case we once want to add other
 * encoding rules. 
 * 
 * Normally, toplevel is used. but we have to increase the level, if
 * we use a type as a part of a composite type (see below).
 */

class xios
{
  enum __flags
    { 
      __touched = 1,
      __debug   = 1<<1,
      __hl7er   = 1<<2,
      __astmer  = 1<<3,
#if WITH_XDR
      __xdr     = 1<<4,
#endif
      ERMASK    = ( __debug | __hl7er | __astmer 
#if WITH_XDR
		    | __xdr 
#endif
		    ),
    };
  
 private:
  int  _flags;
  ios* _ios;
  Delimiters::level_t _level;
  Delimiters          _delimiters;
#if WITH_XDR
  Xdr  _xdr;
#endif

  static int _index;

 public:
  xios(ios& s);

  void debug();
  void hl7er();
  void astmer();
  void touch();
  void untouch();
  
  bool isdebug() const;
  bool ishl7er() const;
  bool isastmer() const;
  bool istouched() const;

  Delimiters::level_t getlevel() const;
  void setlevel(Delimiters::level_t l);

  inline friend xios *__xios(const ios& s);

  inline friend ios& debug(ios& s);
  inline friend ios& hl7er(ios& s);
  inline friend ios& astmer(ios& s);
  inline friend ios& touch(ios& s);
  inline friend ios& untouch(ios& s);
  
  inline friend bool ishl7er(const ios& io);
  inline friend bool isastmer(const ios& io);
  inline friend bool isdebug(const ios& io);
  inline friend bool istouched(const ios& io);
  
  inline friend Delimiters::level_t level(const ios& io);
  inline friend void setlevel(ios&, Delimiters::level_t l);  
  
  inline friend Delimiters& delims(ios& io);
  inline friend const char *getdel(const ios& io, Delimiters::level_t offset);

#if WITH_XDR
  void xdr();
  bool isxdr() const;
  inline friend ios& xdr(ios& s);
  inline friend bool isxdr(const ios& io);
  inline friend Xdr& getxdr(ios& io);
#endif
};

#ifndef OUTLINE
# include "xios.icc"
#endif

#endif /* !PG_XIOS_ */