/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
 * Version: NPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Netscape Public License
 * Version 1.1 (the "License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License at
 * http://www.mozilla.org/NPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is mozilla.org code.
 *
 * The Initial Developer of the Original Code is 
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1998
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or 
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the NPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the NPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */



#include "rdf-int.h"

char* error_string = NULL;
int lineNumber = 0;
void
main (int argc, char* argv[]) {
  RDFFile rf = initFileStruct();
  int ok = 1;
  error_string = getMem(1000);
  if (argc == 2) {
    FILE* f = fopen(argv[1], "r");
    if (f != NULL) {
      char* buff = getMem(RDF_BUF_SIZE);
	  int len;
      while (ok && ((len = fread(buff, 1, RDF_BUF_SIZE-1, f)) > 0)) {
        buff[len] = '\0';
        ok = parseNextRDFXMLBlobInt(rf,  buff, strlen(buff));    
        memset(buff, '\0', RDF_BUF_SIZE);
      }
    }
    if (ok) {
      while (1) {
        char* nextQuery = getMem(200);
        int n;
        nextQuery = gets(nextQuery);
        if (nextQuery) {
          char** ans = processRDFQuery(nextQuery);
          if (ans) {
            for (n = 0; ans[n] != NULL; n++) {
              printf("%s\n", ans[n]);
            }
          }
        } else {
          break;
        }
      }
    }    
  }
}

void 
RDF_Init () {
  error_string = getMem(1000);
}

int
RDF_DigestNewStuff (char* fileName, char* data, int len) {
  RDFFile rf = initFileStruct();
  int ok = 1;
  ok = parseNextRDFXMLBlobInt(rf, data, len);    
  freeMem(rf->line);
  freeMem(rf->holdOver);
  return ok;
}
  

RDFFile
initFileStruct (void) {
  RDFFile ans = (RDFFile)getMem(sizeof(RDF_FileStruct));
  ans->line = (char*)getMem(RDF_BUF_SIZE);
  ans->holdOver = (char*)getMem(RDF_BUF_SIZE);
  ans->depth = 1;
  ans->lastItem = ans->stack[0] ;
  return ans;
}


PRBool
startsWith (const char* pattern, const char* uuid)
{
  int l1 = strlen(pattern);
  int l2 = strlen(uuid);
  int n;
  if (l2 < l1) return 0;
  for (n = 0; n < l1; n++) {
    if (pattern[n] != uuid[n]) return 0;
  } 
  return 1;
}

char* 
getMem (size_t n) {
  char* ans = (char*) malloc(n);
  if (ans) memset(ans, '\0', n);
  return ans;
}

void 
freeMem(void* item) {
  free(item);
}

char 
decodeEntityRef (char* string, int* stringIndexPtr, int len) {
  if (startsWith("lt;", string)) {
    *stringIndexPtr = *stringIndexPtr + 3;
    return '<';
  } else if (startsWith("gt;", string)) {
    *stringIndexPtr = *stringIndexPtr + 3;
    return '>';
  } else  if (startsWith("amp;", string)) {
    *stringIndexPtr = *stringIndexPtr + 4;
    return '&';
  } else return '&';
}

char *
copyStringIgnoreWhiteSpace(char* string)
{
   int len = strlen(string);
   char* buf = (char*)getMem(len + 1);
   PRBool inWhiteSpace = 1;
   int buffIndex = 0;
   int stringIndex = 0;

   while (stringIndex < len) {
     char nextChar = *(string + stringIndex);
     PRBool wsp = wsCharp(nextChar);
     if (!wsp) {
       if (nextChar == '&') {
         *(buf + buffIndex++) = decodeEntityRef(&string[stringIndex+1], 
                                                &stringIndex, len-stringIndex);
       } else {
         *(buf + buffIndex++) = nextChar;
       }
       inWhiteSpace = 0;
     } else if (!inWhiteSpace) {
       *(buf + buffIndex++) = ' ';
       inWhiteSpace = 1;
     } else {
       inWhiteSpace = 1;
     }
     stringIndex++;
   }

   return buf;
}

char *
getHref(char** attlist)
{
	char* ans = getAttributeValue(attlist, "resource");
	if (!ans) ans = getAttributeValue(attlist, "rdf:resource");
	return ans;
}


char *
getID(char** attlist)
{
	char* ans = getAttributeValue(attlist, "id");
	if (!ans) ans = getAttributeValue(attlist, "about"); 
	if (!ans) ans = getAttributeValue(attlist, "rdf:about");
	return ans;
}
 

int 
parseNextRDFXMLBlobInt(RDFFile f, char* blob, int size) {
  int n, last, m;
  PRBool somethingseenp = 0;
  n = last = 0; 
  while (n < size) {
    char c = blob[n];
    if ((c == '\n') || (c == '\r')) lineNumber++;
    m = 0;
    somethingseenp = 0;
    memset(f->line, '\0', RDF_BUF_SIZE-1);
    if (f->holdOver[0] != '\0') {
      memcpy(f->line, f->holdOver, strlen(f->holdOver));
      m = strlen(f->holdOver);
      somethingseenp = 1;
      memset(f->holdOver, '\0', RDF_BUF_SIZE-1);
    }   
    while ((n < size) && (wsCharp(c))) {
      c = blob[++n]; 
      if ((c == '\n') || (c == '\r')) lineNumber++;
    }
    while ((m < RDF_BUF_SIZE) && (c != '<') && (c != '>')) {
      f->line[m] = c;
      m++;
      somethingseenp = (somethingseenp || (!(wsCharp(c))));
      n++;	
      if (n < size) c = blob[n]; 
      else break;
      if ((c == '\n') || (c == '\r')) lineNumber++;
    }
    if (c == '>') f->line[m] = c;
    n++;
    if (m > 0) {
      if ((c == '<') || (c == '>')) {
        last = n;
        if (c == '<') f->holdOver[0] = '<'; 
        if (somethingseenp == 1) {
          int ok = parseNextRDFToken(f, f->line);
          if (!ok) 
			  return 0;
        }
      } else if (size > last) {
        memcpy(f->holdOver, f->line, m);
      }
    } else if (c == '<') f->holdOver[0] = '<';
  }
  return(1);
}

char *
getAttributeValue (char** attlist, char* elName)
{
  size_t n = 0;
  if (!attlist) return NULL;
  while ((n < 2*MAX_ATTRIBUTES) && (*(attlist + n) != NULL)) {
    if (strcmp(*(attlist + n), elName) == 0) return *(attlist + n + 1);
    n = n + 2;
  }
  return NULL;
}

char* 
copyString (char* str) {
  char* ans = getMem(strlen(str)+1);
  if (ans) {
    memcpy(ans, str, strlen(str));
    return ans;
  } else return NULL;
}

void
addElementProps (char** attlist, char* elementName, RDFFile f, RDF_Resource obj)
{
  int count = 0;
  while (count < 2*MAX_ATTRIBUTES) {
    char* attName = attlist[count++];
    char* attValue = attlist[count++];
    if ((attName == NULL) || (attValue == NULL)) break;
    if (!stringEquals(attName, "resource") && 
        !stringEquals(attName, "rdf:resource")  && 
        !stringEquals(attName, "about") && 
        !stringEquals(attName, "rdf:about") && 
        !stringEquals(attName, "tv") &&
        !stringEquals(attName, "id")) {
      remoteStoreAdd(f, obj, getResource(f, attName), 
                   copyStringIgnoreWhiteSpace(attValue), 
                   RDF_STRING_TYPE, 1);
    }
  }
}
        
int
parseNextRDFToken (RDFFile f, char* token)
{
  char* attlist[2*MAX_ATTRIBUTES+1];
  char* elementName;
  if (token[0] == '<') {
    size_t len = strlen(token);
    if (token[len-2] != '/') {
      if (token[1] == '/') {
        char* tok = getMem(len);
        memcpy(tok, &token[2], len-3);
        if (!stringEquals(tok, f->tagStack[f->tagDepth-1])) {
          sprintf(error_string, "Unbalanced tags : Expecting </%s>, found %s", 
                  f->tagStack[f->tagDepth-1], token);
          return 0;
        } else {
          f->tagDepth--;
          freeMem(tok);
        }
      } 
    }
  }
        
  if (token[0] != '<')   {
    if ((f->status == EXPECTING_OBJECT) && (f->depth > 1)) {
      RDF_Resource u = f->stack[f->depth-2];
      RDF_Resource s = f->stack[f->depth-1];
      char* val      = copyStringIgnoreWhiteSpace(token);
      remoteStoreAdd(f, u, s, val , RDF_STRING_TYPE, 1);
    } else  {
      sprintf(error_string, "Did not expect \n\"%s\".\n Was expecting a tag.", token);
      return 0;
    } 
  } else if  (startsWith("<!--", token)) {
    return 1;
  } else if (token[1] == '?')  {
    return 1;
  } else if (token[1] == '/') {
    if ((f->status != EXPECTING_OBJECT) && (f->status != EXPECTING_PROPERTY)) {
      sprintf(error_string, "Did not expect %s. Something pretty screwed up", token);
      return 0;
    }
    if (f->depth > 0) f->depth--;
    f->status = (f->status == EXPECTING_OBJECT ? EXPECTING_PROPERTY : EXPECTING_OBJECT);
    return 1;
  } else if ((f->status == 0) && (startsWith("<RDF:RDF", token) || 
                                  startsWith("<RDF>", token))) {
    f->tagStack[f->tagDepth++] = copyString("RDF"); 
    f->status = EXPECTING_OBJECT;
    return 1;
  } else {
    PRBool emptyElementp = (token[strlen(token)-2] == '/');  
    if ((f->status != EXPECTING_OBJECT) && (f->status != EXPECTING_PROPERTY)) return 1;
    if (!tokenizeElement(token, attlist, &elementName)) return 0;
    if (!emptyElementp) 
		f->tagStack[f->tagDepth++] = copyString(elementName);
    if (f->status == EXPECTING_OBJECT) {
      char* url = NULL;
      RDF_Resource obj;
      int count = 0;    
      url = getID(attlist);
      if (!url) {
        if (f->tagDepth > 2) {
          sprintf(error_string, "Unbalanced tags : Expecting </%s>, found %s", 
                  f->tagStack[f->tagDepth-2], token);
        } else {
          sprintf(error_string, "Require a \"about\" attribute on %s", token);
        }
        return 0;
      }
      obj =  getResource(f, url);
      addElementProps (attlist, elementName, f, obj) ;
      if (!stringEquals(elementName, "RDF:Description")) {
          RDF_Resource eln = getResource(f, elementName);
          remoteStoreAdd(f, obj, getResource(NULL, "instanceOf"), 
                       eln, RDF_RESOURCE_TYPE, 
                       1);        
      }
      if (f->depth > 1) {
        remoteStoreAdd(f, f->stack[f->depth-2], f->stack[f->depth-1], obj, 
                     RDF_RESOURCE_TYPE, 1);
      }
      if (!emptyElementp) {
        f->stack[f->depth++] = obj;
        f->status = EXPECTING_PROPERTY;
      }
    } else if (f->status == EXPECTING_PROPERTY) {
      char* url;
      RDF_Resource obj;
      int count = 0;
      url = getHref(attlist) ;      
      if (url) {
        RDF_Resource eln = getResource(f, elementName);
        char* tvAtt = getAttributeValue(attlist, "tv");
        obj =  getResource(f, url);        
        freeMem(url);
        addElementProps (attlist, elementName, f, obj) ;     
        remoteStoreAdd(f, f->stack[f->depth-1], eln, obj, RDF_RESOURCE_TYPE,  1);
                     
      } 
      if (!emptyElementp) {
        f->stack[f->depth++] = getResource(f, elementName);
        f->status = EXPECTING_OBJECT;
      }
    }
  }
}	



int
tokenizeElement (char* attr, char** attlist, char** elementName)
{
  size_t n = 1;
  size_t s = strlen(attr); 
  char c ;
  size_t m = 0;
  size_t atc = 0;
  PRBool emptyTagp =  (attr[s-2] == '/');
  PRBool inAttrNamep = 1;
  c = attr[n++]; 
  while (wsCharp(c)) {
    c = attr[n++];
  }
  *elementName = &attr[n-1];
  while (n < s) {
    if (wsCharp(c)) break;
    c = attr[n++];
  }
  attr[n-1] = '\0';
  while (atc < 2*MAX_ATTRIBUTES+1) {*(attlist + atc++) = NULL;}
  atc = 0;
  s = (emptyTagp ? s-2 : s-1);
  while (n < s) {
    PRBool attributeOpenStringSeenp = 0;
    m = 0;
    c = attr[n++];
    while ((n <= s) && (atc < 2*MAX_ATTRIBUTES)) {
      if (inAttrNamep && (m > 0) && (wsCharp(c) || (c == '='))) {
	attr[n-1] = '\0';
	*(attlist + atc++) = &attr[n-m-1];
	break;
      }
      if  (!inAttrNamep && attributeOpenStringSeenp && (c == '"')) {
	attr[n-1] = '\0';
	*(attlist + atc++) = &attr[n-m-1];
	break;
      }
      if (inAttrNamep) {
	if ((m > 0) || (!wsCharp(c))) m++;
      } else {
	if (c == '"') {
	  attributeOpenStringSeenp = 1;
	} else {
	  if ((m > 0) || (!(wsCharp(c)))) m++;
	}
      }
      c = attr[n++];
    }
    inAttrNamep = (inAttrNamep ? 0 : 1);
  }
  return 1;
}