/*
 * @project      The CERN Tape Archive (CTA)
 * @copyright    Copyright © 2021-2022 CERN
 * @license      This program is free software, distributed under the terms of the GNU General Public
 *               Licence version 3 (GPL Version 3), copied verbatim in the file "COPYING". You can
 *               redistribute it and/or modify it under the terms of the GPL Version 3, or (at your
 *               option) 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.
 *
 *               In applying this licence, CERN does not waive the privileges and immunities
 *               granted to it by virtue of its status as an Intergovernmental Organization or
 *               submit itself to any jurisdiction.
 */

#include "common/exception/Exception.hpp"
#include "rdbms/wrapper/ParamNameToIdx.hpp"

#include <sstream>

namespace cta::rdbms::wrapper {

//------------------------------------------------------------------------------
// constructor
//------------------------------------------------------------------------------
ParamNameToIdx::ParamNameToIdx(const std::string &sql) {
  bool waitingForAParam = true;
  std::ostringstream paramName;
  uint32_t paramIdx = 1;

  for(const char *ptr = sql.c_str(); ; ptr++) {
    if(waitingForAParam) {

      if('\0' == *ptr) {
        break;
      }

      if(':' == *ptr) {
        // We need to overlook ':=' in PL/SQL code (at least)
        if (isValidParamNameChar(*(ptr+1))) {
          waitingForAParam = false;
          paramName << ":";
        }
      }

    } else { // Currently processing a parameter name

      if(isValidParamNameChar(*ptr)) {
        paramName << *ptr;
      } else {
        if(paramName.str().empty()) {
          throw exception::Exception("Parse error: Empty SQL parameter name");
        }
        if(m_nameToIdx.find(paramName.str()) != m_nameToIdx.end()) {
          throw exception::Exception("Parse error: SQL parameter " + paramName.str() + " is a duplicate");
        }
        m_nameToIdx[paramName.str()] = paramIdx;
        paramName.str(std::string()); // Clear the stream
        paramIdx++;
        waitingForAParam = true;
      }

      if('\0' == *ptr) {
        break;
      }
    }
  }
}

//------------------------------------------------------------------------------
// isValidParamNameChar
//------------------------------------------------------------------------------
bool ParamNameToIdx::isValidParamNameChar(const char c) {
  return ('0' <= c && c <= '9') ||
         ('A' <= c && c <= 'Z') ||
         ('a' <= c && c <= 'z') ||
         c == '_';
}

//------------------------------------------------------------------------------
// getIdx
//------------------------------------------------------------------------------
uint32_t ParamNameToIdx::getIdx(const std::string &paramName) const {
  auto itor = m_nameToIdx.find(paramName);
  if(itor == m_nameToIdx.end()) {
    throw exception::Exception(std::string(__FUNCTION__) + " failed: The SQL parameter " + paramName +
      " does not exist");
  }
  return itor->second;
}

} // namespace cta::rdbms::wrapper