/*

 * Licensed to the Apache Software Foundation (ASF) under one or more

 * contributor license agreements.  See the NOTICE file distributed with

 * this work for additional information regarding copyright ownership.

 * The ASF licenses this file to You under the Apache License, Version 2.0

 * (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.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

#include <log4cxx/logstring.h>

#include <log4cxx/pattern/patternparser.h>

#include <log4cxx/pattern/literalpatternconverter.h>

#include <log4cxx/helpers/loglog.h>

using namespace LOG4CXX_NS;

using namespace LOG4CXX_NS::pattern;

using namespace LOG4CXX_NS::helpers;

const logchar PatternParser::ESCAPE_CHAR = 0x25; // '%'

/**

 * Private constructor.

 */

PatternParser::PatternParser()

{

}

bool PatternParser::isUnicodeIdentifierStart(logchar ch)

{

  //

  //   greatly simplified version checks if

  //     character is USACII alpha or number

  //

  return (ch >= 0x41 /* 'A' */ && ch <= 0x5A /* 'Z' */) ||

    (ch >= 0x61 /* 'a' */ && ch <= 0x7A /* 'z' */) ||

    (ch >= 0x30 /* '0' */ && ch <= 0x39 /* '9' */);

}

bool PatternParser::isUnicodeIdentifierPart(logchar ch)

{

  //

  //   greatly simplified version checks if

  //     character is USACII alpha or number

  //

  return isUnicodeIdentifierStart(ch)

    || (ch == 0x5F /* '_' */);

}

size_t PatternParser::extractConverter(

  logchar lastChar, const LogString& pattern,

  LogString::size_type i, LogString& convBuf,

  LogString& currentLiteral)

{

  if (!convBuf.empty())

  {

    convBuf.erase(convBuf.begin(), convBuf.end());

  }

  // When this method is called, lastChar points to the first character of the

  // conversion word. For example:

  // For "%hello"     lastChar = 'h'

  // For "%-5hello"   lastChar = 'h'

  //System.out.println("lastchar is "+lastChar);

  if (!isUnicodeIdentifierStart(lastChar))

  {

    return i;

  }

  convBuf.append(1, lastChar);

  while (

    (i < pattern.length())

    && isUnicodeIdentifierPart(pattern[i]))

  {

    convBuf.append(1, pattern[i]);

    currentLiteral.append(1, pattern[i]);

    //System.out.println("conv buffer is now ["+convBuf+"].");

    i++;

  }

  return i;

}

size_t PatternParser::extractOptions(const LogString& pattern, LogString::size_type i,

  std::vector<LogString>& options)

{

  while ((i < pattern.length()) && (pattern[i] == 0x7B /* '{' */))

  {

    size_t end = pattern.find(0x7D /* '}' */, i);

    if (end == pattern.npos)

    {

      break;

    }

    LogString r(pattern.substr(i + 1, end - i - 1));

    options.push_back(r);

    i = end + 1;

  }

  return i;

}

void PatternParser::parse(

  const LogString& pattern,

  std::vector<PatternConverterPtr>& patternConverters,

  std::vector<FormattingInfoPtr>& formattingInfos,

  const PatternMap& rules)

{

  LogString currentLiteral;

  size_t patternLength = pattern.length();

  int state = LITERAL_STATE;

  logchar c;

  size_t i = 0;

  int minDigitCount{ 0 }, maxDigitCount{ 0 };

  FormattingInfoPtr formattingInfo(FormattingInfo::getDefault());

  while (i < patternLength)

  {

    c = pattern[i++];

    switch (state)

    {

      case LITERAL_STATE:

        // In literal state, the last char is always a literal.

        if (i == patternLength)

        {

          currentLiteral.append(1, c);

          continue;

        }

        if (c == ESCAPE_CHAR)

        {

          // peek at the next char.

          if (pattern[i] == ESCAPE_CHAR)

          {

            currentLiteral.append(1, c);

            i++; // move pointer

          }

          else

          {

            if (!currentLiteral.empty())

            {

              patternConverters.push_back(

                LiteralPatternConverter::newInstance(currentLiteral));

              formattingInfos.push_back(FormattingInfo::getDefault());

              currentLiteral.erase(currentLiteral.begin(), currentLiteral.end());

            }

            currentLiteral.append(1, c); // append %

            state = CONVERTER_STATE;

            formattingInfo = FormattingInfo::getDefault();

          }

        }

        else

        {

          currentLiteral.append(1, c);

        }

        break;

      case CONVERTER_STATE:

        currentLiteral.append(1, c);

        switch (c)

        {

          case 0x2D: // '-'

            formattingInfo = std::make_shared<FormattingInfo>(

                  true, formattingInfo->getMinLength(),

                  formattingInfo->getMaxLength());

            break;

          case 0x2E: // '.'

            state = DOT_STATE;

            break;

          default:

            if ((c >= 0x30 /* '0' */) && (c <= 0x39 /* '9' */))

            {

              formattingInfo = std::make_shared<FormattingInfo>(

                    formattingInfo->isLeftAligned(), c - 0x30 /* '0' */,

                    formattingInfo->getMaxLength());

              state = MIN_STATE;

              minDigitCount = 1;

            }

            else

            {

              i = finalizeConverter(

                  c, pattern, i, currentLiteral, formattingInfo,

                  rules, patternConverters, formattingInfos);

              // Next pattern is assumed to be a literal.

              state = LITERAL_STATE;

              formattingInfo = FormattingInfo::getDefault();

              if (!currentLiteral.empty())

              {

                currentLiteral.erase(currentLiteral.begin(), currentLiteral.end());

              }

            }

        } // switch

        break;

      case MIN_STATE:

        currentLiteral.append(1, c);

        if ((c >= 0x30 /* '0' */) && (c <= 0x39 /* '9' */) && minDigitCount < 3)

        {

          formattingInfo = std::make_shared<FormattingInfo>(

                formattingInfo->isLeftAligned(),

                (formattingInfo->getMinLength() * 10) + (c - 0x30 /* '0' */),

                formattingInfo->getMaxLength());

          ++minDigitCount;

        }

        else if (c == 0x2E /* '.' */)

        {

          state = DOT_STATE;

        }

        else

        {

          i = finalizeConverter(

              c, pattern, i, currentLiteral, formattingInfo,

              rules, patternConverters, formattingInfos);

          state = LITERAL_STATE;

          formattingInfo = FormattingInfo::getDefault();

          if (!currentLiteral.empty())

          {

            currentLiteral.erase(currentLiteral.begin(), currentLiteral.end());

          }

        }

        break;

      case DOT_STATE:

        currentLiteral.append(1, c);

        if ((c >= 0x30 /* '0' */) && (c <= 0x39 /* '9' */))

        {

          formattingInfo = std::make_shared<FormattingInfo>(

                formattingInfo->isLeftAligned(), formattingInfo->getMinLength(),

                c - 0x30 /* '0' */);

          state = MAX_STATE;

          maxDigitCount = 1;

        }

        else

        {

          LogLog::error(LOG4CXX_STR("Error in pattern, was expecting digit."));

          state = LITERAL_STATE;

        }

        break;

      case MAX_STATE:

        currentLiteral.append(1, c);

        if ((c >= 0x30 /* '0' */) && (c <= 0x39 /* '9' */) && maxDigitCount < 3)

        {

          formattingInfo = std::make_shared<FormattingInfo>(

                formattingInfo->isLeftAligned(), formattingInfo->getMinLength(),

                (formattingInfo->getMaxLength() * 10) + (c - 0x30 /* '0' */));

          ++maxDigitCount;

        }

        else

        {

          i = finalizeConverter(

              c, pattern, i, currentLiteral, formattingInfo,

              rules, patternConverters, formattingInfos);

          state = LITERAL_STATE;

          formattingInfo = FormattingInfo::getDefault();

          if (!currentLiteral.empty())

          {

            currentLiteral.erase(currentLiteral.begin(), currentLiteral.end());

          }

        }

        break;

    } // switch

  }

  // while

  if (currentLiteral.length() != 0)

  {

    patternConverters.push_back(

      LiteralPatternConverter::newInstance(currentLiteral));

    formattingInfos.push_back(FormattingInfo::getDefault());

  }

}

PatternConverterPtr PatternParser::createConverter(

  const LogString& converterId,

  LogString& currentLiteral,

  const PatternMap& rules,

  std::vector<LogString>& options)

{

  LogString converterName(converterId);

  for (size_t i = converterId.length(); i > 0; i--)

  {

    converterName = converterName.substr(0, i);

    PatternMap::const_iterator iter = rules.find(converterName);

    if (iter != rules.end())

    {

      currentLiteral.erase(currentLiteral.begin(),

        currentLiteral.end() - (converterId.length() - i));

      return (iter->second)(options);

    }

  }

  LogLog::error(LogString(LOG4CXX_STR("Unrecognized format specifier ")) + converterId);

  return PatternConverterPtr();

}

size_t PatternParser::finalizeConverter(

  logchar c, const LogString& pattern, size_t i,

  LogString& currentLiteral, const FormattingInfoPtr& formattingInfo,

  const PatternMap&  rules,

  std::vector<PatternConverterPtr>& patternConverters,

  std::vector<FormattingInfoPtr>&  formattingInfos)

{

  LogString convBuf;

  i = extractConverter(c, pattern, i, convBuf, currentLiteral);

  if (convBuf.empty())

  {

    LogLog::error(LOG4CXX_STR("Empty conversion specifier"));

    patternConverters.push_back(

      LiteralPatternConverter::newInstance(currentLiteral));

    formattingInfos.push_back(FormattingInfo::getDefault());

  }

  else

  {

    LogString converterId(convBuf);

    std::vector<LogString> options;

    i = extractOptions(pattern, i, options);

    PatternConverterPtr pc(

      createConverter(

        converterId, currentLiteral, rules, options));

    if (pc == NULL)

    {

      LogString msg(LOG4CXX_STR("Unrecognized conversion specifier ["));

      msg.append(converterId);

      msg.append(LOG4CXX_STR("] in conversion pattern."));

      LogLog::error(msg);

      patternConverters.push_back(

        LiteralPatternConverter::newInstance(currentLiteral));

      formattingInfos.push_back(FormattingInfo::getDefault());

    }

    else

    {

      patternConverters.push_back(pc);

      formattingInfos.push_back(formattingInfo);

      if (currentLiteral.length() > 0)

      {

        patternConverters.push_back(

          LiteralPatternConverter::newInstance(currentLiteral));

        formattingInfos.push_back(FormattingInfo::getDefault());

      }

    }

  }

  if (!currentLiteral.empty())

  {

    currentLiteral.erase(currentLiteral.begin(), currentLiteral.end());

  }

  return i;

}