/*
 * 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.
 */
#include "pg_config.h"

IDENT("@(#) Composite.cc (Gunther Schadow) 12/19/96");

#pragma implementation

#include "Composite.h"
#include "DataTypeCode.h"
#include "xios.h"
#include "Delimiters.h"
#include "misc.h"
#include "exception.h"
#include "logfile.h"
#include "ParseTrace.h"

#define ITEM(i) ( & ( this ->* itemtab[i].memberp ) )

void Composite::unset()
{
  LOGDEBUG("unset %styp",
	   (const char *)DataTypeCode((DataTypeCode::Value)type()));

  int i;

  for(i=0; i<noitems; i++)
    ITEM(i)->unset();
 
  Type::unset();
}

void Composite::nullify()
{
  LOGDEBUG("nullify %styp",
	   (const char *)DataTypeCode((DataTypeCode::Value)type()));

  int i;

  for(i=0; i<noitems; i++)
    ITEM(i)->unset();

  Type::nullify();
}

bool Composite::OK() const
{
  LOGDEBUG("check %styp",
	   (const char *)DataTypeCode((DataTypeCode::Value)type()));

  int i;

  for(i=0; i<noitems; i++)
    if(!ITEM(i)->OK())
      return FALSE;

  return Type::OK();
}

bool Composite::commit()
{
  LOGDEBUG("commit %styp",
	   (const char *)DataTypeCode((DataTypeCode::Value)type()));

  int i;
  bool isset = FALSE;

  for(i=0; i<noitems; i++)
    isset = ITEM(i)->commit() || isset;

  if(isset)
    set();
  else if(ispresent())
    unset(); // enforce a valid state

  return isset;
}

result Composite::input(istream& is)
{
  CompositeTracer tracer((DataTypeCode::Value)type());

  LOGDEBUG("input %styp",
	   (const char *)DataTypeCode((DataTypeCode::Value)type()));

  if(isdebug(is))
    FATAL("can't read from debug stream");

  const char *dset = getdel(is, Delimiters::cmplevel);

  // any composite member must use a subcomponent delimiter 
  Delimiters::level_t currlevel = level(is);
  setlevel(is, (Delimiters::level_t)(currlevel - 1));

  bool eoc_seen = FALSE;
  int i;

  for(i=0; i<noitems; i++)
    {
      Type *item = ITEM(i);
      tracer.next((DataTypeCode::Value)item->type());

      if(eoc_seen)
	item->unset();
      else
	{
	  item->input(is);
	  eoc_seen = !match(is, dset);
	}

      if(i==0 && eoc_seen)        // if there is nothing but the first item
	{
	  if(!item->ispresent()) // and it is not present `||'
	    {
	      unset();           // the whole composite object is absent
	      goto finish;
	    }
	  if(item->isnull())     // or it is null `|""|'
	    {
	      nullify();         // the whole composite object is null
	      goto finish;
	    }
	}
    }

  set();

 finish:
  // reset the level to normal
  setlevel(is, currlevel);
  return SUCCESS;
}

void Composite::output(ostream& os) const
{
  LOGDEBUG("output %styp",
	   (const char *)DataTypeCode((DataTypeCode::Value)type()));

  if(ishl7er(os) || isastmer(os))
    {
      if(ispresent())
	{
	  char eoc = *getdel(os, Delimiters::cmplevel);
      
	  // any composite member must use a subcomponent delimiter 
	  Delimiters::level_t currlevel = level(os);
	  setlevel(os, (Delimiters::level_t)(currlevel - 1));

	  int i = 0;
	  while(i<noitems)
	    {
	      ITEM(i++)->output(os);
	      if(i==noitems) break;
	      os << eoc;
	    }

	  // reset the level to normal
	  setlevel(os, currlevel);
	}
    }
  else /* debug output */
    {
      if(ispresent())
	{
	  int i=0;
	  while(i<noitems)
	    {
	      ITEM(i++)->output(os);
	      if(i==noitems) break;
	      os << DSSEPR;
	    }
	}
      else
	os << DSNOPS;

      os << DSEGRP;
    }
}