/*
 * 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/ConfigEntry.h>
#include <Common/ConfigManager.h>
#include <Common/Logger.h>
#include <Net/ThreadManager.h>

#include <sstream>

#include <boost/bind.hpp>
#include <boost/regex.hpp>


namespace Mad {
namespace Modules {

boost::shared_ptr<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);
}


boost::shared_ptr<std::map<unsigned long, Common::UserInfo> > UserBackendMysql::getUserList() throw(Net::Exception) {
  Net::ThreadManager::get()->detach();

  if(mysql_ping(mysql))
    throw Net::Exception(Net::Exception::NOT_AVAILABLE);

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

  if(!result || mysql_num_fields(result) < 4)
    throw Net::Exception(Net::Exception::NOT_AVAILABLE);

  boost::shared_ptr<std::map<unsigned long, Common::UserInfo> > users(new std::map<unsigned long, Common::UserInfo>());

  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));
  }

  return users;
}

boost::shared_ptr<Common::UserInfo> UserBackendMysql::getUserInfo(unsigned long uid) throw(Net::Exception) {
  Net::ThreadManager::get()->detach();

  if(mysql_ping(mysql))
    throw Net::Exception(Net::Exception::NOT_AVAILABLE);

  std::string query = queryUserById;

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

  query = boost::regex_replace(query, boost::regex("\\{UID\\}"), tmp.str(), boost::match_default);

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

  if(!result || mysql_num_fields(result) < 4)
    throw Net::Exception(Net::Exception::NOT_AVAILABLE);

  MYSQL_ROW row = mysql_fetch_row(result);

  if(row) {
    boost::shared_ptr<Common::UserInfo> user(new Common::UserInfo(strtoul(row[0], 0, 10), row[2]));

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

    while((row = mysql_fetch_row(result)) != 0) {}

    return user;
  }

  throw Net::Exception(Net::Exception::NOT_AVAILABLE);
}

boost::shared_ptr<Common::UserInfo> UserBackendMysql::getUserInfoByName(const std::string &name) throw(Net::Exception) {
  Net::ThreadManager::get()->detach();

  if(mysql_ping(mysql))
    throw Net::Exception(Net::Exception::NOT_AVAILABLE);

  boost::scoped_array<char> escapedName(new char[name.length()*2+1]);

  mysql_real_escape_string(mysql, escapedName.get(), name.c_str(), name.length());

  std::string query = boost::regex_replace(queryUserByName, boost::regex("\\{USER\\}"), "\""+std::string(escapedName.get())+"\"", boost::match_default);

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

  if(!result || mysql_num_fields(result) < 4)
    throw Net::Exception(Net::Exception::NOT_AVAILABLE);

  MYSQL_ROW row = mysql_fetch_row(result);

  if(row) {
    boost::shared_ptr<Common::UserInfo> user(new Common::UserInfo(strtoul(row[0], 0, 10), row[2]));

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

    while((row = mysql_fetch_row(result)) != 0) {}

    return user;
  }

  throw Net::Exception(Net::Exception::NOT_AVAILABLE);
}

boost::shared_ptr<std::set<unsigned long> > UserBackendMysql::getUserGroups(unsigned long uid) throw(Net::Exception) {
  Net::ThreadManager::get()->detach();

  if(mysql_ping(mysql))
    throw Net::Exception(Net::Exception::NOT_AVAILABLE);

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

  std::string query = boost::regex_replace(queryListUserGroups, boost::regex("\\{UID\\}"), tmp.str(), boost::match_default);

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

  if(!result || mysql_num_fields(result) < 1)
    throw Net::Exception(Net::Exception::NOT_AVAILABLE);

  boost::shared_ptr<std::set<unsigned long> > groups(new std::set<unsigned long>);

  while(MYSQL_ROW row = mysql_fetch_row(result))
    groups->insert(strtoul(row[0], 0, 10));

  return groups;
}


boost::shared_ptr<std::map<unsigned long, Common::GroupInfo> > UserBackendMysql::getGroupList() throw(Net::Exception) {
  Net::ThreadManager::get()->detach();

  if(mysql_ping(mysql))
    throw Net::Exception(Net::Exception::NOT_AVAILABLE);

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

  if(!result || mysql_num_fields(result) < 2)
    throw Net::Exception(Net::Exception::NOT_AVAILABLE);

  boost::shared_ptr<std::map<unsigned long, Common::GroupInfo> > groups(new std::map<unsigned long, Common::GroupInfo>());

  while(MYSQL_ROW row = mysql_fetch_row(result)) {
    Common::GroupInfo group(strtoul(row[0], 0, 10), row[1]);

    groups->insert(std::make_pair(group.getGid(), group));
  }

  return groups;
}

std::string UserBackendMysql::getGroupName(unsigned long gid) throw(Net::Exception) {
  Net::ThreadManager::get()->detach();

  if(mysql_ping(mysql))
    throw Net::Exception(Net::Exception::NOT_AVAILABLE);

  std::string query = queryGroupById;

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

  query = boost::regex_replace(query, boost::regex("\\{GID\\}"), tmp.str(), boost::match_default);

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

  if(!result || mysql_num_fields(result) < 2)
    throw Net::Exception(Net::Exception::NOT_AVAILABLE);

  MYSQL_ROW row = mysql_fetch_row(result);

  if(row)
    return row[1];

  throw Net::Exception(Net::Exception::NOT_AVAILABLE);
}

unsigned long UserBackendMysql::getGroupId(const std::string &name) throw(Net::Exception) {
  Net::ThreadManager::get()->detach();

  if(mysql_ping(mysql))
    throw Net::Exception(Net::Exception::NOT_AVAILABLE);

  boost::scoped_array<char> escapedName(new char[name.length()*2+1]);

  mysql_real_escape_string(mysql, escapedName.get(), name.c_str(), name.length());

  std::string query = boost::regex_replace(queryGroupByName, boost::regex("\\{GROUP\\}"), "\""+std::string(escapedName.get())+"\"", boost::match_default);

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

  if(!result || mysql_num_fields(result) < 2)
    throw Net::Exception(Net::Exception::NOT_AVAILABLE);

  MYSQL_ROW row = mysql_fetch_row(result);

  if(row)
    return strtoul(row[0], 0, 10);

  throw Net::Exception(Net::Exception::NOT_AVAILABLE);
}

boost::shared_ptr<std::set<unsigned long> > UserBackendMysql::getGroupUsers(unsigned long gid) throw(Net::Exception) {
  Net::ThreadManager::get()->detach();

  if(mysql_ping(mysql))
    throw Net::Exception(Net::Exception::NOT_AVAILABLE);

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

  std::string query = boost::regex_replace(queryListGroupUsers, boost::regex("\\{GID\\}"), tmp.str(), boost::match_default);

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

  if(!result || mysql_num_fields(result) < 1)
    throw Net::Exception(Net::Exception::NOT_AVAILABLE);

  boost::shared_ptr<std::set<unsigned long> > users(new std::set<unsigned long>);

  while(MYSQL_ROW row = mysql_fetch_row(result))
    users->insert(strtoul(row[0], 0, 10));

  return users;
}


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

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

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

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

  backend.reset();
}

}
}

extern "C" {

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

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

}