/* d4tag.c   (c)Copyright Sequiter Software Inc., 1990-1994.  All rights reserved. */

#include "d4all.h"
#ifndef S4UNIX
#ifdef __TURBOC__
#pragma hdrstop
#endif
#endif

TAG4 *S4FUNCTION d4tag( DATA4 *d4, char *tag_name )
{
#ifndef S4INDEX_OFF
  char tag_lookup[11] ;
  TAG4 *tag_on ;

#ifdef S4VBASIC
  if ( c4parm_check( d4, 2, E4_D4TAG ) )
    return 0 ;
#endif

  if ( d4 == 0 || tag_name == 0 )
#ifdef S4DEBUG
    e4severe( e4parm, E4_D4TAG ) ;
#else
  return 0 ;
#endif

  u4ncpy( tag_lookup, tag_name, sizeof( tag_lookup ) ) ;
  c4upper( tag_lookup ) ;

  for( tag_on = 0 ;; )
  {
    tag_on = d4tag_next( d4, tag_on ) ;
    if ( tag_on == 0 )
      break ;
    if ( strcmp( tag_on->alias, tag_lookup ) == 0 )
      return tag_on ;
  }

  if ( d4->code_base->tag_name_error )
    e4( d4->code_base, e4tag_name, tag_name ) ;
#endif
  return 0 ;
}

TAG4 *S4FUNCTION d4tag_default( DATA4 *d4 )
{
#ifndef S4INDEX_OFF
  TAG4 *tag ;
  INDEX4 *index ;

#ifdef S4VBASIC
  if ( c4parm_check( d4, 2, E4_D4TAG_DEF ) )
    return 0 ;
#endif

  if ( d4 == 0 )
#ifdef S4DEBUG
    e4severe( e4parm, E4_D4TAG_DEF ) ;
#else
  return 0 ;
#endif

  tag = d4tag_selected( d4 ) ;
  if ( tag )
    return tag ;

  index = (INDEX4 *) l4first( &d4->indexes ) ;
  if ( index )
  {
    tag = (TAG4 *) l4first( &index->tags ) ;
    if ( tag )
      return tag ;
  }
#endif
  return 0 ;
}

TAG4 *S4FUNCTION d4tag_next( DATA4 *d4, TAG4 *tag_on )
{
#ifdef S4INDEX_OFF
  return 0 ;
#else
  INDEX4 *i4 ;

#ifdef S4VBASIC
  if ( c4parm_check( d4, 2, E4_D4TAG_NEXT ) )
    return 0 ;
#endif

  if ( d4 == 0 )
#ifdef S4DEBUG
    e4severe( e4parm, E4_D4TAG_NEXT ) ;
#else
  return 0 ;
#endif

  if ( tag_on == 0 )
  {
    i4 = (INDEX4 *)l4first( &d4->indexes ) ;
    if ( i4 == 0 )
      return 0 ;
  }
  else
    i4 = tag_on->index ;

  tag_on = (TAG4 *)l4next( &i4->tags, tag_on ) ;
  if ( tag_on )
    return tag_on ;

  i4 = (INDEX4 *)l4next( &d4->indexes, i4 ) ;
  if ( i4 == 0 )
    return 0 ;

  return (TAG4 *)l4first( &i4->tags ) ;
#endif
}

TAG4 *S4FUNCTION d4tag_prev( DATA4 *d4, TAG4 *tag_on )
{
#ifdef S4INDEX_OFF
  return 0 ;
#else
  INDEX4 *i4 ;

#ifdef S4VBASIC
  if ( c4parm_check( d4, 2, E4_D4TAG_PREV ) )
    return 0 ;
#endif

  if ( d4 == 0 )
#ifdef S4DEBUG
    e4severe( e4parm, E4_D4TAG_PREV ) ;
#else
  return 0 ;
#endif

  if ( tag_on == 0 )
  {
    i4 = (INDEX4 *)l4last( &d4->indexes ) ;
    if ( i4 == 0 )
      return 0 ;
  }
  else
    i4 = tag_on->index ;

  tag_on = (TAG4 *)l4prev( &i4->tags, tag_on ) ;
  if ( tag_on )
    return tag_on ;

  i4 = (INDEX4 *)l4prev( &d4->indexes, i4 ) ;
  if ( i4 == 0 )
    return 0 ;

  return (TAG4 *)l4last( &i4->tags ) ;
#endif
}

void S4FUNCTION d4tag_select( DATA4 *d4, TAG4 *t4 )
{
#ifdef S4VBASIC
  if ( c4parm_check( d4, 2, E4_D4TAG_SELECT ) )
    return ;
#endif

  if ( d4 == 0 )
#ifdef S4DEBUG
    e4severe( e4parm, E4_D4TAG_SELECT ) ;
#else
  return ;
#endif

#ifdef S4INDEX_OFF
  if ( t4 != 0 )
    e4( d4->code_base, e4not_index, E4_D4TAG_SELECT ) ;
#else
#ifdef S4DEBUG
  if ( t4 )
    if ( t4->index->data != d4 )
      e4severe( e4parm, E4_D4TAG_SELECT ) ;
#endif

  if ( t4 == 0 )
    d4->indexes.selected = 0 ;
  else
  {
    d4->indexes.selected = (void *) t4->index ;
    t4->index->tags.selected = (void *)t4 ;
  }
#endif
}

TAG4 *S4FUNCTION d4tag_selected( DATA4 *d4 )
{
#ifndef S4INDEX_OFF
  INDEX4 *index ;
  TAG4 *tag ;

  if ( d4 == 0 )
#ifdef S4DEBUG
    e4severe( e4parm, E4_D4TAG_SELECTED ) ;
#else
  return 0 ;
#endif

  index = (INDEX4 *)d4->indexes.selected ;
  if ( index )
  {
    tag = (TAG4 *)index->tags.selected ;
    if ( tag )
      return tag ;
  }
#endif
  return 0 ;
}

#ifdef S4VB_DOS

TAG4 *d4tag_v( DATA4 *d4, char *name )
{
  return d4tag( d4, c4str(name) ) ;
}

#endif