//
// HtRegexList.cc
//
// HtRegex: A list of HtRegex objects for handling large regex patterns
//
// Part of the ht://Dig package   <http://www.htdig.org/>
// Copyright (c) 1999-2004 The ht://Dig Group
// For copyright details, see the file COPYING in your distribution
// or the GNU Library General Public License (LGPL) version 2 or later 
// <http://www.gnu.org/copyleft/lgpl.html>
//
// $Id: HtRegexList.cc,v 1.5 2004/05/28 13:15:21 lha Exp $
//

#ifdef HAVE_CONFIG_H
#include "htconfig.h"
#endif /* HAVE_CONFIG_H */

#include "HtRegexList.h"
#include <locale.h>

class listnode
{
public:
  listnode		*next;
  Object		*object;
};

HtRegexList::HtRegexList()
{
	compiled = 0;
}

HtRegexList::~HtRegexList()
{
	compiled = 0;
}

const String &HtRegexList::lastError()
{
	return lastErrorMessage;
}

int
HtRegexList::setEscaped(StringList &list, int case_sensitive)
{
  if (list.Count() == 0)
    {
      compiled = false;
      return true;
    }

  String  *str;
  String  transformedLimits, currentPattern, prevPattern;
  HtRegex *limit = new HtRegex;

  list.Start_Get();
  while ((str = (String *) list.Get_Next()))
    {
      if (str->indexOf('[') == 0 && str->lastIndexOf(']') == str->length()-1)
	{
	  transformedLimits = str->sub(1,str->length()-2).get();
	}
      else 	// Backquote any regex special characters
	{
	  transformedLimits = 0;
	  for (int pos = 0; pos < str->length(); pos++)
	    { 
	      if (strchr("^.[$()|*+?{\\", str->Nth(pos)))
		transformedLimits << '\\';
	      transformedLimits << str->Nth(pos);
	    }
	}
      if (!currentPattern.empty())
	currentPattern << "|";
      currentPattern << transformedLimits;
      if (!limit->set(currentPattern.get(), case_sensitive))
	{
	  if (prevPattern.empty()) // we haven't set anything yet!
	    {
	      	lastErrorMessage = limit->lastError();
		compiled = 0;
		return false;
	    }
	  limit->set(prevPattern.get(), case_sensitive); // Go back a step
	  Add(limit);
	  limit = new HtRegex;
	  currentPattern = transformedLimits;
	  if (!limit->set(currentPattern.get(), case_sensitive))
	    {
	      	lastErrorMessage = limit->lastError();
		compiled = 0;
		return false;
	    }
	}
      prevPattern = currentPattern;
    }
  Add(limit); // OK, we're done so just add the last compiled pattern
  
  compiled = 1;
  return true;
}

int
HtRegexList::match(const char * str, int nullpattern, int nullstr)
{
  HtRegex *regx;
	
  if (compiled == 0) return(nullpattern);
  if (str == NULL) return(nullstr);
  if (strlen(str) <= 0) return(nullstr);

  if (number == 0) return(1);	// An empty pattern matches everything

  Start_Get();
  while ((regx = (HtRegex *) Get_Next()))
    {
      if (regx->match(str, nullpattern, nullstr))
	{
	  // Move this one to the front and update pointers
  	  if (cursor.current_index != -1)
  	    {
  	      if (cursor.prev)
  		cursor.prev->next = cursor.current->next;
  	      cursor.prev = 0;
  	      cursor.current->next = head;
  	      head = cursor.current;
  	      cursor.current = head;
  	      cursor.current_index = -1;
  	    }
	  return(1);
	}
    }

  return(0);
}