/* -*- Mode: c; c-basic-offset: 2 -*-
 *
 * raptor_statement.c - Raptor statements
 *
 * Copyright (C) 2008, David Beckett http://www.dajobe.org/
 * 
 * This package is Free Software and part of Redland http://librdf.org/
 * 
 * It is licensed under the following three licenses as alternatives:
 *   1. GNU Lesser General Public License (LGPL) V2.1 or any newer version
 *   2. GNU General Public License (GPL) V2 or any newer version
 *   3. Apache License, V2.0 or any newer version
 * 
 * You may not use this file except in compliance with at least one of
 * the above three licenses.
 * 
 * See LICENSE.html or LICENSE.txt at the top of this package for the
 * complete terms and further detail along with the license texts for
 * the licenses in COPYING.LIB, COPYING and LICENSE-2.0.txt respectively.
 * 
 */

#ifdef HAVE_CONFIG_H
#include <raptor_config.h>
#endif

#ifdef WIN32
#include <win32_raptor_config.h>
#endif


#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <stdarg.h>
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif

/* Raptor includes */
#include "raptor.h"
#include "raptor_internal.h"


/* prototypes for helper functions */
static void raptor_print_statement_part_as_ntriples(raptor_world* world, FILE* stream, const void *term, raptor_identifier_type type, raptor_uri* literal_datatype, const unsigned char *literal_language);
static void raptor_print_statement_as_ntriples_common(raptor_world* world, const raptor_statement *statement, FILE *stream);
static int raptor_statement_compare_common(raptor_world* world, const raptor_statement *s1, const raptor_statement *s2);


/**
 * raptor_statement_copy_v2:
 * @statement: statement to copy
 *
 * Copy a #raptor_statement. 
 *
 * Return value: a new #raptor_statement_v2 or NULL on error
 */
raptor_statement_v2*
raptor_statement_copy_v2(const raptor_statement_v2 *statement)
{
  return raptor_statement_copy_v2_from_v1(statement->world, statement->s);
}


/**
 * raptor_statement_copy_v2_from_v1:
 * @world: raptor_world object
 * @statement: statement to copy
 *
 * Copy a #raptor_statement and wrap it in #raptor_statement_v2.
 *
 * Return value: a new #raptor_statement_v2 or NULL on error
 */
raptor_statement_v2*
raptor_statement_copy_v2_from_v1(raptor_world* world, const raptor_statement *statement)
{
  raptor_statement_v2 *s;

  s=(raptor_statement_v2*)RAPTOR_CALLOC(raptor_statement_v2, 1, sizeof(raptor_statement_v2));
  if(!s)
    return NULL;

  s->world=world;
  s->s=raptor_statement_copy(world, statement);
  if(!s->s) {
    raptor_free_statement_v2(s);
    s=NULL;
  }

  return s;
}


/**
 * raptor_statement_copy:
 * @world: raptor_world object
 * @statement: statement to copy
 *
 * Copy a #raptor_statement.
 *
 * Return value: a new #raptor_statement or NULL on error
 */
raptor_statement*
raptor_statement_copy(raptor_world* world, const raptor_statement *statement)
{
  raptor_statement *s;

  s=(raptor_statement*)RAPTOR_CALLOC(raptor_statement, 1, sizeof(raptor_statement));
  if(!s)
    return NULL;

  s->subject_type=statement->subject_type;
  if(statement->subject_type == RAPTOR_IDENTIFIER_TYPE_ANONYMOUS) {
    unsigned char *new_blank=(unsigned char*)RAPTOR_MALLOC(cstring, strlen((char*)statement->subject)+1);
    if(!new_blank)
      goto oom;
    strcpy((char*)new_blank, (const char*)statement->subject);
    s->subject=new_blank;
  } else if(statement->subject_type == RAPTOR_IDENTIFIER_TYPE_ORDINAL) {
    s->subject=raptor_new_uri_from_rdf_ordinal(world, *((int*)statement->subject));
    s->subject_type=RAPTOR_IDENTIFIER_TYPE_RESOURCE;
  } else
    s->subject=raptor_uri_copy_v2(world, (raptor_uri*)statement->subject);

  s->predicate_type=RAPTOR_IDENTIFIER_TYPE_RESOURCE;
  if(statement->predicate_type == RAPTOR_IDENTIFIER_TYPE_ORDINAL)
    s->predicate=raptor_new_uri_from_rdf_ordinal(world, *((int*)statement->predicate));
  else
    s->predicate=raptor_uri_copy_v2(world, (raptor_uri*)statement->predicate);


  s->object_type=statement->object_type;
  if(statement->object_type == RAPTOR_IDENTIFIER_TYPE_LITERAL || 
     statement->object_type == RAPTOR_IDENTIFIER_TYPE_XML_LITERAL) {
    unsigned char *string;
    char *language=NULL;
    raptor_uri *uri=NULL;
    
    string=(unsigned char*)RAPTOR_MALLOC(cstring, strlen((char*)statement->object)+1);
    if(!string)
      goto oom;
    strcpy((char*)string, (const char*)statement->object);
    s->object=string;

    if(statement->object_literal_language) {
      language=(char*)RAPTOR_MALLOC(cstring, strlen((const char*)statement->object_literal_language)+1);
      if(!language)
        goto oom;
      strcpy(language, (const char*)statement->object_literal_language);
      s->object_literal_language=(const unsigned char*)language;
    }

    if(statement->object_type == RAPTOR_IDENTIFIER_TYPE_XML_LITERAL) {
      /* nop */
    } else if(statement->object_literal_datatype) {
      uri=raptor_uri_copy_v2(world, (raptor_uri*)statement->object_literal_datatype);
      s->object_literal_datatype=uri;
    }
  } else if(statement->object_type == RAPTOR_IDENTIFIER_TYPE_ANONYMOUS) {
    char *blank=(char*)statement->object;
    unsigned char *new_blank=(unsigned char*)RAPTOR_MALLOC(cstring, strlen(blank)+1);
    if(!new_blank)
      goto oom;
    strcpy((char*)new_blank, (const char*)blank);
    s->object=new_blank;
  } else if(statement->object_type == RAPTOR_IDENTIFIER_TYPE_ORDINAL) {
    s->object=raptor_new_uri_from_rdf_ordinal(world, *((int*)statement->object));
    s->object_type=RAPTOR_IDENTIFIER_TYPE_RESOURCE;
  } else {
    raptor_uri *uri=raptor_uri_copy_v2(world, (raptor_uri*)statement->object);
    s->object=uri;
  }

  return s;

  oom:
  raptor_free_statement(world, s);
  return NULL;
}


/**
 * raptor_free_statement_v2:
 * @statement: statement
 *
 * Destructor
 *
 */
void
raptor_free_statement_v2(raptor_statement_v2 *statement)
{
  RAPTOR_ASSERT_OBJECT_POINTER_RETURN(statement, raptor_statement);
  raptor_free_statement(statement->world, statement->s);
  RAPTOR_FREE(raptor_statement_v2, statement);
}


/**
 * raptor_free_statement:
 * @statement: statement
 *
 * Destructor
 *
 */
void
raptor_free_statement(raptor_world *world, raptor_statement *statement)
{
  if(statement->subject) {
    if(statement->subject_type == RAPTOR_IDENTIFIER_TYPE_RESOURCE)
      raptor_free_uri_v2(world, (raptor_uri*)statement->subject);
    else
      RAPTOR_FREE(cstring, (void*)statement->subject);
  }

  if(statement->predicate) {
    if(statement->predicate_type == RAPTOR_IDENTIFIER_TYPE_PREDICATE ||
       statement->predicate_type == RAPTOR_IDENTIFIER_TYPE_RESOURCE)
      raptor_free_uri_v2(world, (raptor_uri*)statement->predicate);
    else
      RAPTOR_FREE(cstring, (void*)statement->predicate);
  }

  if(statement->object_type == RAPTOR_IDENTIFIER_TYPE_RESOURCE) {
    if(statement->object)
      raptor_free_uri_v2(world, (raptor_uri*)statement->object);
  } else {
    if(statement->object)
      RAPTOR_FREE(cstring, (void*)statement->object);

    if(statement->object_literal_language)
      RAPTOR_FREE(cstring, (void*)statement->object_literal_language);
    if(statement->object_literal_datatype)
      raptor_free_uri_v2(world, (raptor_uri*)statement->object_literal_datatype);
  }

  RAPTOR_FREE(raptor_statement, statement);
}


#ifndef RAPTOR_DISABLE_V1
/**
 * raptor_print_statement:
 * @statement: #raptor_statement object to print
 * @stream: #FILE* stream
 *
 * Print a raptor_statement to a stream.
 *
 * raptor_init() MUST have been called before calling this function.
 * Use raptor_print_statement_v2() if using raptor_world APIs.
 **/
void
raptor_print_statement(const raptor_statement * statement, FILE *stream) 
{
  raptor_print_statement_v1(raptor_world_instance(), statement, stream);
}
#endif


/**
 * raptor_print_statement_v2:
 * @statement: #raptor_statement_v2 object to print
 * @stream: #FILE* stream
 *
 * Print a raptor_statement to a stream.
 **/
void
raptor_print_statement_v2(const raptor_statement_v2 * statement, FILE *stream) 
{
  raptor_print_statement_v1(statement->world, statement->s, stream);
}


/**
 * raptor_print_statement_v1:
 * @world: raptor_world object
 * @statement: #raptor_statement object to print
 * @stream: #FILE* stream
 *
 * Print a raptor_statement to a stream.
 **/
void
raptor_print_statement_v1(raptor_world* world, const raptor_statement * statement, FILE *stream) 
{
  fputc('[', stream);

  if(statement->subject_type == RAPTOR_IDENTIFIER_TYPE_ANONYMOUS) {
    fputs((const char*)statement->subject, stream);
  } else {
#ifdef RAPTOR_DEBUG
    if(!statement->subject)
      RAPTOR_FATAL1("Statement has NULL subject URI\n");
#endif
    fputs((const char*)raptor_uri_as_string_v2(world, (raptor_uri*)statement->subject), stream);
  }

  fputs(", ", stream);

  if(statement->predicate_type == RAPTOR_IDENTIFIER_TYPE_ORDINAL)
    fprintf(stream, "[rdf:_%d]", *((int*)statement->predicate));
  else {
#ifdef RAPTOR_DEBUG
    if(!statement->predicate)
      RAPTOR_FATAL1("Statement has NULL predicate URI\n");
#endif
    fputs((const char*)raptor_uri_as_string_v2(world, (raptor_uri*)statement->predicate), stream);
  }

  fputs(", ", stream);

  if(statement->object_type == RAPTOR_IDENTIFIER_TYPE_LITERAL || 
     statement->object_type == RAPTOR_IDENTIFIER_TYPE_XML_LITERAL) {
    if(statement->object_type == RAPTOR_IDENTIFIER_TYPE_XML_LITERAL) {
      fputc('<', stream);
      fputs((const char*)raptor_xml_literal_datatype_uri_string, stream);
      fputc('>', stream);
    } else if(statement->object_literal_datatype) {
      fputc('<', stream);
      fputs((const char*)raptor_uri_as_string_v2(world, (raptor_uri*)statement->object_literal_datatype), stream);
      fputc('>', stream);
    }
    fputc('"', stream);
    fputs((const char*)statement->object, stream);
    fputc('"', stream);
  } else if(statement->object_type == RAPTOR_IDENTIFIER_TYPE_ANONYMOUS)
    fputs((const char*)statement->object, stream);
  else if(statement->object_type == RAPTOR_IDENTIFIER_TYPE_ORDINAL)
    fprintf(stream, "[rdf:_%d]", *((int*)statement->object));
  else {
#ifdef RAPTOR_DEBUG
    if(!statement->object)
      RAPTOR_FATAL1("Statement has NULL object URI\n");
#endif
    fputs((const char*)raptor_uri_as_string_v2(world, (raptor_uri*)statement->object), stream);
  }

  fputc(']', stream);
}


#if !defined(RAPTOR_DISABLE_DEPRECATED) && !defined(RAPTOR_DISABLE_V1)
/**
 * raptor_print_statement_detailed:
 * @statement: #raptor_statement object to print
 * @detailed: unused
 * @stream: #FILE* stream
 *
 * Print a raptor_statement to a stream in a detailed fashion.
 *
 * raptor_init() MUST have been called before calling this function.
 *
 * @deprecated: an internal function, do not use.
 *
 * No current difference from calling raptor_print_statement().
 *
 **/
void
raptor_print_statement_detailed(const raptor_statement * statement, 
                                int detailed, FILE *stream) 
{
  raptor_print_statement(statement, stream);
}
#endif


#ifndef RAPTOR_DISABLE_V1
/**
 * raptor_statement_part_as_counted_string:
 * @term: #raptor_statement part (subject, predicate, object)
 * @type: #raptor_statement part type
 * @literal_datatype: #raptor_statement part datatype
 * @literal_language: #raptor_statement part language
 * @len_p: Pointer to location to store length of new string (if not NULL)
 *
 * Turns part of raptor statement into a N-Triples format counted string.
 * 
 * Turns the given @term into an N-Triples escaped string using all the
 * escapes as defined in http://www.w3.org/TR/rdf-testcases/#ntriples
 *
 * The part (subject, predicate, object) of the raptor_statement is
 * typically passed in as @term, the part type (subject_type,
 * predicate_type, object_type) is passed in as @type.  When the part
 * is a literal, the @literal_datatype and @literal_language fields
 * are set, otherwise NULL (usually object_datatype,
 * object_literal_language).
 *
 * raptor_init() MUST have been called before calling this function.
 * Use raptor_statement_part_as_counted_string_v2() if using raptor_world APIs.
 *
 * Return value: the new string or NULL on failure.  The length of
 * the new string is returned in *@len_p if len_p is not NULL.
 **/
unsigned char*
raptor_statement_part_as_counted_string(const void *term, 
                                        raptor_identifier_type type,
                                        raptor_uri* literal_datatype,
                                        const unsigned char *literal_language,
                                        size_t* len_p)
{
  return raptor_statement_part_as_counted_string_v2(raptor_world_instance(),
                                                    term,
                                                    type,
                                                    literal_datatype,
                                                    literal_language,
                                                    len_p);
}
#endif


/**
 * raptor_statement_part_as_counted_string_v2:
 * @world: raptor_world object
 * @term: #raptor_statement part (subject, predicate, object)
 * @type: #raptor_statement part type
 * @literal_datatype: #raptor_statement part datatype
 * @literal_language: #raptor_statement part language
 * @len_p: Pointer to location to store length of new string (if not NULL)
 *
 * Turns part of raptor statement into a N-Triples format counted string.
 * 
 * Turns the given @term into an N-Triples escaped string using all the
 * escapes as defined in http://www.w3.org/TR/rdf-testcases/#ntriples
 *
 * The part (subject, predicate, object) of the raptor_statement is
 * typically passed in as @term, the part type (subject_type,
 * predicate_type, object_type) is passed in as @type.  When the part
 * is a literal, the @literal_datatype and @literal_language fields
 * are set, otherwise NULL (usually object_datatype,
 * object_literal_language).
 *
 * Return value: the new string or NULL on failure.  The length of
 * the new string is returned in *@len_p if len_p is not NULL.
 **/
unsigned char*
raptor_statement_part_as_counted_string_v2(raptor_world* world,
                                           const void *term, 
                                           raptor_identifier_type type,
                                           raptor_uri* literal_datatype,
                                           const unsigned char *literal_language,
                                           size_t* len_p)
{
  size_t len=0, term_len, uri_len;
  size_t language_len=0;
  unsigned char *s, *buffer=NULL;
  unsigned char *uri_string=NULL;
  
  switch(type) {
    case RAPTOR_IDENTIFIER_TYPE_LITERAL:
    case RAPTOR_IDENTIFIER_TYPE_XML_LITERAL:
      term_len=strlen((const char*)term);
      len=2+term_len;
      if(literal_language && type == RAPTOR_IDENTIFIER_TYPE_LITERAL) {
        language_len=strlen((const char*)literal_language);
        len+= language_len+1;
      }
      if(type == RAPTOR_IDENTIFIER_TYPE_XML_LITERAL)
        len += 4+raptor_xml_literal_datatype_uri_string_len;
      else if(literal_datatype) {
        uri_string=raptor_uri_as_counted_string_v2(world, (raptor_uri*)literal_datatype, &uri_len);
        len += 4+uri_len;
      }
  
      buffer=(unsigned char*)RAPTOR_MALLOC(cstring, len+1);
      if(!buffer)
        return NULL;

      s=buffer;
      *s++ ='"';
      /* raptor_print_ntriples_string(stream, (const char*)term, '"'); */
      strcpy((char*)s, (const char*)term);
      s+= term_len;
      *s++ ='"';
      if(literal_language && type == RAPTOR_IDENTIFIER_TYPE_LITERAL) {
        *s++ ='@';
        strcpy((char*)s, (const char*)literal_language);
        s+= language_len;
      }

      if(type == RAPTOR_IDENTIFIER_TYPE_XML_LITERAL) {
        *s++ ='^';
        *s++ ='^';
        *s++ ='<';
        strcpy((char*)s, (const char*)raptor_xml_literal_datatype_uri_string);
        s+= raptor_xml_literal_datatype_uri_string_len;
        *s++ ='>';
      } else if(literal_datatype) {
        *s++ ='^';
        *s++ ='^';
        *s++ ='<';
        strcpy((char*)s, (const char*)uri_string);
        s+= uri_len;
        *s++ ='>';
      }
      *s++ ='\0';
      
      break;
      
    case RAPTOR_IDENTIFIER_TYPE_ANONYMOUS:
      len=2+strlen((const char*)term);
      buffer=(unsigned char*)RAPTOR_MALLOC(cstring, len+1);
      if(!buffer)
        return NULL;
      s=buffer;
      *s++ ='_';
      *s++ =':';
      strcpy((char*)s, (const char*)term);
      break;
      
    case RAPTOR_IDENTIFIER_TYPE_ORDINAL:
      len=raptor_rdf_namespace_uri_len + 13; 
      buffer=(unsigned char*)RAPTOR_MALLOC(cstring, len+1);
      if(!buffer)
        return NULL;

      sprintf((char*)buffer, "<%s_%d>",
              raptor_rdf_namespace_uri, *((int*)term));
      break;
  
    case RAPTOR_IDENTIFIER_TYPE_RESOURCE:
    case RAPTOR_IDENTIFIER_TYPE_PREDICATE:
      uri_string=raptor_uri_as_counted_string_v2(world, (raptor_uri*)term, &uri_len);
      len=2+uri_len;
      buffer=(unsigned char*)RAPTOR_MALLOC(cstring, len+1);
      if(!buffer)
        return NULL;

      s=buffer;
      *s++ ='<';
      /* raptor_print_ntriples_string(stream, raptor_uri_as_string((raptor_uri*)term), '\0'); */
      strcpy((char*)s, (const char*)uri_string);
      s+= uri_len;
      *s++ ='>';
      *s++ ='\0';
      break;
      
    case RAPTOR_IDENTIFIER_TYPE_UNKNOWN:
    default:
      RAPTOR_FATAL2("Unknown type %d", type);
  }

  if(len_p)
    *len_p=len;
  
 return buffer;
}


#ifndef RAPTOR_DISABLE_V1
/**
 * raptor_statement_part_as_string:
 * @term: #raptor_statement part (subject, predicate, object)
 * @type: #raptor_statement part type
 * @literal_datatype: #raptor_statement part datatype
 * @literal_language: #raptor_statement part language
 *
 * Turns part of raptor statement into a N-Triples format string.
 * 
 * Turns the given @term into an N-Triples escaped string using all the
 * escapes as defined in http://www.w3.org/TR/rdf-testcases/#ntriples
 *
 * The part (subject, predicate, object) of the raptor_statement is
 * typically passed in as @term, the part type (subject_type,
 * predicate_type, object_type) is passed in as @type.  When the part
 * is a literal, the @literal_datatype and @literal_language fields
 * are set, otherwise NULL (usually object_datatype,
 * object_literal_language).
 *
 * raptor_init() MUST have been called before calling this function.
 * Use raptor_statement_part_as_string_v2() if using raptor_world APIs.
 *
 * Return value: the new string or NULL on failure.
 **/
unsigned char*
raptor_statement_part_as_string(const void *term, 
                                raptor_identifier_type type,
                                raptor_uri* literal_datatype,
                                const unsigned char *literal_language)
{
  return raptor_statement_part_as_string_v2(raptor_world_instance(),
                                            term,
                                            type,
                                            literal_datatype,
                                            literal_language);
}
#endif


/**
 * raptor_statement_part_as_string_v2:
 * @world: raptor_world object
 * @term: #raptor_statement part (subject, predicate, object)
 * @type: #raptor_statement part type
 * @literal_datatype: #raptor_statement part datatype
 * @literal_language: #raptor_statement part language
 *
 * Turns part of raptor statement into a N-Triples format string.
 * 
 * Turns the given @term into an N-Triples escaped string using all the
 * escapes as defined in http://www.w3.org/TR/rdf-testcases/#ntriples
 *
 * The part (subject, predicate, object) of the raptor_statement is
 * typically passed in as @term, the part type (subject_type,
 * predicate_type, object_type) is passed in as @type.  When the part
 * is a literal, the @literal_datatype and @literal_language fields
 * are set, otherwise NULL (usually object_datatype,
 * object_literal_language).
 *
 * Return value: the new string or NULL on failure.
 **/
unsigned char*
raptor_statement_part_as_string_v2(raptor_world* world,
                                   const void *term, 
                                   raptor_identifier_type type,
                                   raptor_uri* literal_datatype,
                                   const unsigned char *literal_language)
{
  return raptor_statement_part_as_counted_string_v2(world, term, type,
                                                    literal_datatype,
                                                    literal_language,
                                                    NULL);
}


static void
raptor_print_statement_part_as_ntriples(raptor_world* world,
                                        FILE* stream,
                                        const void *term, 
                                        raptor_identifier_type type,
                                        raptor_uri* literal_datatype,
                                        const unsigned char *literal_language) 
{
  switch(type) {
    case RAPTOR_IDENTIFIER_TYPE_LITERAL:
    case RAPTOR_IDENTIFIER_TYPE_XML_LITERAL:
      fputc('"', stream);
      raptor_print_ntriples_string(stream, (const unsigned char*)term, '"');
      fputc('"', stream);
      if(literal_language && type == RAPTOR_IDENTIFIER_TYPE_LITERAL) {
        fputc('@', stream);
        fputs((const char*)literal_language, stream);
      }
      if(type == RAPTOR_IDENTIFIER_TYPE_XML_LITERAL) {
        fputs("^^<", stream);
        fputs((const char*)raptor_xml_literal_datatype_uri_string, stream);
        fputc('>', stream);
      } else if(literal_datatype) {
        fputs("^^<", stream);
        fputs((const char*)raptor_uri_as_string_v2(world, (raptor_uri*)literal_datatype), stream);
        fputc('>', stream);
      }

      break;
      
    case RAPTOR_IDENTIFIER_TYPE_ANONYMOUS:
      fputs("_:", stream);
      fputs((const char*)term, stream);
      break;
      
    case RAPTOR_IDENTIFIER_TYPE_ORDINAL:
      fprintf(stream, "<%s_%d>",
              raptor_rdf_namespace_uri, *((int*)term));
      break;
  
    case RAPTOR_IDENTIFIER_TYPE_RESOURCE:
    case RAPTOR_IDENTIFIER_TYPE_PREDICATE:
      fputc('<', stream);
      raptor_print_ntriples_string(stream, raptor_uri_as_string_v2(world, (raptor_uri*)term), '\0');
      fputc('>', stream);
      break;
      
    case RAPTOR_IDENTIFIER_TYPE_UNKNOWN:
    default:
      RAPTOR_FATAL2("Unknown type %d", type);
  }
}


#ifndef RAPTOR_DISABLE_V1
/**
 * raptor_print_statement_as_ntriples:
 * @statement: #raptor_statement to print
 * @stream: #FILE* stream
 *
 * Print a raptor_statement in N-Triples form.
 *
 * raptor_init() MUST have been called before calling this function.
 * Use raptor_print_statement_as_ntriples_v2() if using raptor_world APIs.
 * 
 **/
void
raptor_print_statement_as_ntriples(const raptor_statement * statement,
                                   FILE *stream) 
{
  raptor_print_statement_as_ntriples_common(raptor_world_instance(),
                                            statement,
                                            stream);
}
#endif


/**
 * raptor_print_statement_as_ntriples_v2:
 * @statement: #raptor_statement_v2 to print
 * @stream: #FILE* stream
 *
 * Print a raptor_statement in N-Triples form.
 * 
 **/
void
raptor_print_statement_as_ntriples_v2(const raptor_statement_v2 * statement,
                                      FILE *stream) 
{
  raptor_print_statement_as_ntriples_common(statement->world,
                                            statement->s,
                                            stream);
}


static void
raptor_print_statement_as_ntriples_common(raptor_world* world,
                                          const raptor_statement *statement,
                                          FILE *stream)
{
  raptor_print_statement_part_as_ntriples(world,
                                          stream,
                                          statement->subject,
                                          statement->subject_type,
                                          NULL, NULL);
  fputc(' ', stream);
  raptor_print_statement_part_as_ntriples(world,
                                          stream,
                                          statement->predicate,
                                          statement->predicate_type,
                                          NULL, NULL);
  fputc(' ', stream);
  raptor_print_statement_part_as_ntriples(world,
                                          stream,
                                          statement->object,
                                          statement->object_type,
                                          statement->object_literal_datatype,
                                          statement->object_literal_language);
  fputs(" .", stream);
}

 
#ifndef RAPTOR_DISABLE_V1
/**
 * raptor_statement_compare:
 * @s1: first statement
 * @s2: second statement
 *
 * Compare a pair of #raptor_statement
 *
 * If types are different, the #raptor_identifier_type order is used.
 * Resource and datatype URIs are compared with raptor_uri_compare(),
 * blank nodes and literals with strcmp().  If one literal has no
 * language, it is earlier than one with a language.  If one literal
 * has no datatype, it is earlier than one with a datatype.
 *
 * raptor_init() MUST have been called before calling this function.
 * Use raptor_statement_compare_v2() if using raptor_world APIs.
 * 
 * Return value: <0 if s1 is before s2, 0 if equal, >0 if s1 is after s2
 */
int
raptor_statement_compare(const raptor_statement *s1,
                         const raptor_statement *s2)
{
  return raptor_statement_compare_common(raptor_world_instance(), s1, s2);
}
#endif


/**
 * raptor_statement_compare_v2:
 * @s1: first statement
 * @s2: second statement
 *
 * Compare a pair of #raptor_statement_v2
 *
 * If types are different, the #raptor_identifier_type order is used.
 * Resource and datatype URIs are compared with raptor_uri_compare(),
 * blank nodes and literals with strcmp().  If one literal has no
 * language, it is earlier than one with a language.  If one literal
 * has no datatype, it is earlier than one with a datatype.
 * 
 * Return value: <0 if s1 is before s2, 0 if equal, >0 if s1 is after s2
 */
int
raptor_statement_compare_v2(const raptor_statement_v2 *s1,
                            const raptor_statement_v2 *s2)
{
  return raptor_statement_compare_common(s1->world, s1->s, s2->s);
}


static int
raptor_statement_compare_common(raptor_world* world,
                                const raptor_statement *s1,
                                const raptor_statement *s2)
{
  int d=0;

  if(s1->subject && s2->subject) {
    d=s1->subject_type != s2->subject_type;
    if(d)
      return d;

    /* subjects are URIs or blank nodes */
    if(s1->subject_type == RAPTOR_IDENTIFIER_TYPE_ANONYMOUS)
      d=strcmp((char*)s1->subject, (char*)s2->subject);
    else
      d=raptor_uri_compare_v2(world,
                              (raptor_uri*)s1->subject,
                              (raptor_uri*)s2->subject);
  } else if(s1->subject || s2->subject)
    d=(!s1->subject ? -1 : 1);
  if(d)
    return d;
  

  /* predicates are URIs */
  if(s1->predicate && s2->predicate) {
    d=raptor_uri_compare_v2(world,
                            (raptor_uri*)s1->predicate,
                            (raptor_uri*)s2->predicate);
  } else if(s1->predicate || s2->predicate)
    d=(!s1->predicate ? -1 : 1);
  if(d)
    return d;


  /* objects are URIs or blank nodes or literals */
  if(s1->object && s2->object) {
    if(s1->object_type == RAPTOR_IDENTIFIER_TYPE_LITERAL || 
       s1->object_type == RAPTOR_IDENTIFIER_TYPE_XML_LITERAL) {
      d=strcmp((char*)s1->object, (char*)s2->object);
      if(d)
        return d;

      if(s1->object_literal_language && s2->object_literal_language) {
        /* both have a language */
        d=strcmp((char*)s1->object_literal_language,
                 (char*)s2->object_literal_language);
      } else if(s1->object_literal_language || s2->object_literal_language)
        /* only one has a language; the language-less one is earlier */
        d=(!s1->object_literal_language ? -1 : 1);
      if(d)
        return d;

      if(s1->object_literal_datatype && s2->object_literal_datatype) {
        /* both have a datatype */
        d=raptor_uri_compare_v2(world,
                                (raptor_uri*)s1->object_literal_datatype,
                                (raptor_uri*)s2->object_literal_datatype);
      } else if(s1->object_literal_datatype || s2->object_literal_datatype)
        /* only one has a datatype; the datatype-less one is earlier */
        d=(!s1->object_literal_datatype ? -1 : 1);
      if(d)
        return d;

    } else if(s1->object_type == RAPTOR_IDENTIFIER_TYPE_ANONYMOUS)
      d=strcmp((char*)s1->object, (char*)s2->object);
    else
      d=raptor_uri_compare_v2(world, (raptor_uri*)s1->object, (raptor_uri*)s2->object);
  } else if(s1->object || s2->object)
    d=(!s1->object ? -1 : 1);

  return d;
}