// -*- c-basic-offset: 2 -*-
/*
 *  Copyright (C) 1999-2001, 2004 Harri Porten (porten@kde.org)
 *  Copyright (c) 2007, 2008 Apple Inc. All rights reserved.
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2 of the License, or (at your option) any later version.
 *
 *  This library 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
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

#include "config.h"
#include "regexp.h"

#include "lexer.h"
#include <pcre/pcre.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <wtf/Assertions.h>
#include <wtf/OwnArrayPtr.h>

namespace KJS {

inline RegExp::RegExp(const UString& pattern)
  : m_pattern(pattern)
  , m_flagBits(0)
  , m_constructionError(0)
  , m_numSubpatterns(0)
{
    m_regExp = jsRegExpCompile(reinterpret_cast<const ::UChar*>(pattern.data()), pattern.size(),
        JSRegExpDoNotIgnoreCase, JSRegExpSingleLine, &m_numSubpatterns, &m_constructionError);
}

PassRefPtr<RegExp> RegExp::create(const UString& pattern)
{
    return adoptRef(new RegExp(pattern));
}

inline RegExp::RegExp(const UString& pattern, const UString& flags)
  : m_pattern(pattern)
  , m_flags(flags)
  , m_flagBits(0)
  , m_constructionError(0)
  , m_numSubpatterns(0)
{
    // NOTE: The global flag is handled on a case-by-case basis by functions like
    // String::match and RegExpImp::match.
    if (flags.find('g') != -1)
        m_flagBits |= Global;

    // FIXME: Eliminate duplication by adding a way ask a JSRegExp what its flags are?
    JSRegExpIgnoreCaseOption ignoreCaseOption = JSRegExpDoNotIgnoreCase;
    if (flags.find('i') != -1) {
        m_flagBits |= IgnoreCase;
        ignoreCaseOption = JSRegExpIgnoreCase;
    }

    JSRegExpMultilineOption multilineOption = JSRegExpSingleLine;
    if (flags.find('m') != -1) {
        m_flagBits |= Multiline;
        multilineOption = JSRegExpMultiline;
    }
    
    m_regExp = jsRegExpCompile(reinterpret_cast<const ::UChar*>(pattern.data()), pattern.size(),
        ignoreCaseOption, multilineOption, &m_numSubpatterns, &m_constructionError);
}

PassRefPtr<RegExp> RegExp::create(const UString& pattern, const UString& flags)
{
    return adoptRef(new RegExp(pattern, flags));
}

RegExp::~RegExp()
{
    jsRegExpFree(m_regExp);
}

int RegExp::match(const UString& s, int i, OwnArrayPtr<int>* ovector)
{
  if (i < 0)
    i = 0;
  if (ovector)
    ovector->clear();

  if (i > s.size() || s.isNull())
    return -1;

  if (!m_regExp)
    return -1;

  // Set up the offset vector for the result.
  // First 2/3 used for result, the last third used by PCRE.
  int* offsetVector;
  int offsetVectorSize;
  int fixedSizeOffsetVector[3];
  if (!ovector) {
    offsetVectorSize = 3;
    offsetVector = fixedSizeOffsetVector;
  } else {
    offsetVectorSize = (m_numSubpatterns + 1) * 3;
    offsetVector = new int [offsetVectorSize];
    ovector->set(offsetVector);
  }

  int numMatches = jsRegExpExecute(m_regExp, reinterpret_cast<const ::UChar*>(s.data()), s.size(), i, offsetVector, offsetVectorSize);

  if (numMatches < 0) {
#ifndef NDEBUG
    if (numMatches != JSRegExpErrorNoMatch)
      fprintf(stderr, "jsRegExpExecute failed with result %d\n", numMatches);
#endif
    if (ovector)
      ovector->clear();
    return -1;
  }

  return offsetVector[0];
}

} // namespace KJS
