/*
 * UserBackendMysql.cpp
 *
 * Copyright (C) 2008 Matthias Schiffer <matthias@gamezock.de>
 *
 * 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
 * (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.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program. If not, see <http://www.gnu.org/licenses/>.
 */

#include <config.h>

#include "UserBackendMysql.h"
#include <Common/ActionManager.h>
#include <Common/ConfigEntry.h>
#include <Common/ConfigManager.h>
#include <Common/Logger.h>

#include <sstream>

#include <boost/bind.hpp>
#include <pcrecpp.h>

#define init UserBackendMysql_LTX_init
#define deinit UserBackendMysql_LTX_deinit


namespace Mad {
namespace Modules {

UserBackendMysql *UserBackendMysql::backend;

bool UserBackendMysql::handleConfigEntry(const Common::ConfigEntry &entry, bool handled) {
  if(handled)
    return false;

  if(entry[0].getKey().matches("UserBackendMysql")) {
    if(entry[1].getKey().matches("Host")) {
      if(entry[2].empty())
        host = entry[1][0];
    }
    else if(entry[1].getKey().matches("Username")) {
      if(entry[2].empty())
        username = entry[1][0];
    }
    else if(entry[1].getKey().matches("Password")) {
      if(entry[2].empty())
        passwd = entry[1][0];
    }
    else if(entry[1].getKey().matches("Database")) {
      if(entry[2].empty())
        db = entry[1][0];
    }
    else if(entry[1].getKey().matches("Port")) {
      if(entry[2].empty()) {
        char *endptr;
        long val;

        val = strtol(entry[1][0].c_str(), &endptr, 10);

        if(endptr != 0 || val < 0 || val > 65535)
          Common::Logger::log(Common::Logger::WARNING, "UserBackendMysql: Invalid port");
        else
          port = val;
      }
    }
    else if(entry[1].getKey().matches("UnixSocket")) {
      if(entry[2].empty())
        unixSocket = entry[1][0];
    }
    else if(entry[1].getKey().matches("Queries")) {
      if(entry[2].getKey().matches("ListUsers")) {
        if(entry[3].empty())
          queryListUsers = entry[2][0];
      }
      else if(entry[2].getKey().matches("ListGroups")) {
        if(entry[3].empty())
          queryListGroups = entry[2][0];
      }
      else if(entry[2].getKey().matches("ListUserGroups")) {
        if(entry[3].empty())
          queryListUserGroups = entry[2][0];
      }
      else if(entry[2].getKey().matches("ListGroupUsers")) {
        if(entry[3].empty())
          queryListGroupUsers = entry[2][0];
      }
      else if(entry[2].getKey().matches("UserById")) {
        if(entry[3].empty())
          queryUserById = entry[2][0];
      }
      else if(entry[2].getKey().matches("UserByName")) {
        if(entry[3].empty())
          queryUserByName = entry[2][0];
      }
      else if(entry[2].getKey().matches("GroupById")) {
        if(entry[3].empty())
          queryGroupById = entry[2][0];
      }
      else if(entry[2].getKey().matches("GroupByName")) {
        if(entry[3].empty())
          queryGroupByName = entry[2][0];
      }
      else if(!entry[2].empty())
        return false;
    }
    else if(!entry[1].empty())
      return false;

    return true;
  }

  return false;
}

void UserBackendMysql::configFinished() {
  if(db.empty()) {
    Common::Logger::log(Common::Logger::ERROR, "UserBackendMysql: No database name given");
    return;
  }

  mysql = mysql_init(0);
  mysql_real_connect(mysql, host.c_str(), username.c_str(), passwd.c_str(), db.c_str(), port, unixSocket.empty() ? 0 : unixSocket.c_str(), 0);

  Server::UserManager::get()->registerBackend(backend);
}


bool UserBackendMysql::getUserList(const boost::function1<void, const std::map<unsigned long, Common::UserInfo>& > &callback) {
  mysql_ping(mysql);

  mysql_real_query(mysql, queryListUsers.c_str(), queryListUsers.length());
  MYSQL_RES *result = mysql_use_result(mysql);

  if(mysql_num_fields(result) < 4)
    return true; // TODO Error

  std::map<unsigned long, Common::UserInfo> users;

  while(MYSQL_ROW row = mysql_fetch_row(result)) {
    Common::UserInfo user(strtoul(row[0], 0, 10), row[2]);

    user.setGid(strtoul(row[1], 0, 10));
    user.setFullName(row[3]);

    users.insert(std::make_pair(user.getUid(), user));
  }

  Common::ActionManager::get()->add(boost::bind(callback, users));

  return true;
}

bool UserBackendMysql::getUserInfo(unsigned long uid, const boost::function1<void, const Common::UserInfo&> &callback) {
  mysql_ping(mysql);

  std::string query = queryUserById;

  std::ostringstream tmp;
  tmp << '"';
  tmp << uid;
  tmp << '"';

  pcrecpp::RE("\\{ID\\}").GlobalReplace(tmp.str(), &query);

  mysql_real_query(mysql, query.c_str(), query.length());
  MYSQL_RES *result = mysql_use_result(mysql);

  if(mysql_num_fields(result) < 4)
    return true; // TODO Error

  MYSQL_ROW row = mysql_fetch_row(result);

  if(row) {
    Common::UserInfo user(strtoul(row[0], 0, 10), row[2]);

    user.setGid(strtoul(row[1], 0, 10));
    user.setFullName(row[3]);

    Common::ActionManager::get()->add(boost::bind(callback, user));

    while((row = mysql_fetch_row(result)) != 0) {}
  }
  else {
    Common::ActionManager::get()->add(boost::bind(callback, Common::UserInfo()));
  }

  return true;
}


void UserBackendMysql::registerBackend() {
  if(backend)
    return;

  backend = new UserBackendMysql();
  Common::ConfigManager::get()->registerConfigurable(backend);
}

void UserBackendMysql::unregisterBackend() {
  if(!backend)
    return;

  Common::ConfigManager::get()->unregisterConfigurable(backend);
  Server::UserManager::get()->unregisterBackend(backend);

  delete backend;
  backend = 0;
}

}
}

extern "C" {

void init() {
  Mad::Modules::UserBackendMysql::registerBackend();
}

void deinit() {
  Mad::Modules::UserBackendMysql::unregisterBackend();
}

}