/*
 * Copyright 2011 Emmanuel Engelhart <kelson@kiwix.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU  General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 * MA 02110-1301, USA.
 */

#include <tools/regexTools.h>

std::map<std::string, icu::RegexMatcher*> regexCache;

icu::RegexMatcher* buildRegex(const std::string& regex)
{
  icu::RegexMatcher* matcher;
  auto itr = regexCache.find(regex);

  /* Regex is in cache */
  if (itr != regexCache.end()) {
    matcher = itr->second;
  }

  /* Regex needs to be parsed (and cached) */
  else {
    UErrorCode status = U_ZERO_ERROR;
    icu::UnicodeString uregex(regex.c_str());
    matcher = new icu::RegexMatcher(uregex, UREGEX_CASE_INSENSITIVE, status);
    regexCache[regex] = matcher;
  }

  return matcher;
}

/* todo */
void freeRegexCache()
{
}
bool matchRegex(const std::string& content, const std::string& regex)
{
  ucnv_setDefaultName("UTF-8");
  icu::UnicodeString ucontent(content.c_str());
  auto matcher = buildRegex(regex);
  matcher->reset(ucontent);
  return matcher->find();
}

std::string replaceRegex(const std::string& content,
                         const std::string& replacement,
                         const std::string& regex)
{
  ucnv_setDefaultName("UTF-8");
  icu::UnicodeString ucontent(content.c_str());
  icu::UnicodeString ureplacement(replacement.c_str());
  auto matcher = buildRegex(regex);
  matcher->reset(ucontent);
  UErrorCode status = U_ZERO_ERROR;
  auto uresult = matcher->replaceAll(ureplacement, status);
  std::string tmp;
  uresult.toUTF8String(tmp);
  return tmp;
}

std::string appendToFirstOccurence(const std::string& content,
                                   const std::string regex,
                                   const std::string& replacement)
{
  ucnv_setDefaultName("UTF-8");
  icu::UnicodeString ucontent(content.c_str());
  icu::UnicodeString ureplacement(replacement.c_str());
  auto matcher = buildRegex(regex);
  matcher->reset(ucontent);

  if (matcher->find()) {
    UErrorCode status = U_ZERO_ERROR;
    ucontent.insert(matcher->end(status), ureplacement);
    std::string tmp;
    ucontent.toUTF8String(tmp);
    return tmp;
  }

  return content;
}
