/*
 * UserCache.cpp
 *
 * Copyright (C) 2009 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 "UserCache.h"
#include "Application.h"

namespace Mad {
namespace Common {

boost::shared_ptr<const std::map<unsigned long, UserInfo> > UserCache::getUserList() throw(Core::Exception) {
  boost::lock_guard<boost::shared_mutex> lock(mutex);

  if(users) {
    application->log(Core::LoggerBase::USER, Core::LoggerBase::DEBUG, "Using cached user list");
    return users;
  }
  else if(userException) {
    application->log(Core::LoggerBase::USER, Core::LoggerBase::DEBUG, "Error cached");
    throw userException;
  }

  try {
    users = backend->getUserList();

    userNames.reset(new std::map<std::string, unsigned long>);
    for(std::map<unsigned long, UserInfo>::const_iterator user = users->begin(); user != users->end(); ++user)
      userNames->insert(std::make_pair(user->second.getUsername(), user->first));

    return users;
  }
  catch(Core::Exception e) {
    userException = e;
    throw userException;
  }
}

boost::shared_ptr<const UserInfo> UserCache::getUserInfo(unsigned long uid) throw(Core::Exception) {
  getUserList();

  boost::lock_guard<boost::shared_mutex> lock(mutex);

  if(!users)
    throw userException;

  std::map<unsigned long, UserInfo>::const_iterator user = users->find(uid);

  if(user == users->end())
    throw Core::Exception(Core::Exception::NOT_FOUND);

  return boost::shared_ptr<UserInfo>(new UserInfo(user->second));
}

boost::shared_ptr<const UserInfo> UserCache::getUserInfoByName(const std::string &name) throw(Core::Exception) {
  getUserList();

  boost::lock_guard<boost::shared_mutex> lock(mutex);

  if(!users)
    throw userException;

  std::map<std::string, unsigned long>::const_iterator uid = userNames->find(name);
  if(uid == userNames->end())
    throw Core::Exception(Core::Exception::NOT_FOUND);

  std::map<unsigned long, UserInfo>::const_iterator user = users->find(uid->second);

  return boost::shared_ptr<UserInfo>(new UserInfo(user->second));
}

boost::shared_ptr<const std::set<unsigned long> > UserCache::getUserGroupList(unsigned long uid) throw(Core::Exception) {
  getFullUserGroupList();

  boost::lock_guard<boost::shared_mutex> lock(mutex);

  if(!userGroups)
    throw userGroupException;

  std::pair<std::multimap<unsigned long, unsigned long>::const_iterator, std::multimap<unsigned long, unsigned long>::const_iterator> range = userGroups->equal_range(uid);

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

  for(std::multimap<unsigned long, unsigned long>::const_iterator group = range.first; group != range.second; ++group)
    groups->insert(group->second);

  return groups;
}


boost::shared_ptr<const std::map<unsigned long, GroupInfo> > UserCache::getGroupList() throw(Core::Exception) {
  boost::lock_guard<boost::shared_mutex> lock(mutex);

  if(groups) {
    application->log(Core::LoggerBase::USER, Core::LoggerBase::DEBUG, "Using cached group list");
    return groups;
  }
  else if(groupException) {
    application->log(Core::LoggerBase::USER, Core::LoggerBase::DEBUG, "Error cached");
    throw groupException;
  }

  try {
    groups = backend->getGroupList();

    groupNames.reset(new std::map<std::string, unsigned long>);
    for(std::map<unsigned long, GroupInfo>::const_iterator group = groups->begin(); group != groups->end(); ++group)
      groupNames->insert(std::make_pair(group->second.getName(), group->first));

    return groups;
  }
  catch(Core::Exception e) {
    groupException = e;
    throw groupException;
  }
}

boost::shared_ptr<const GroupInfo> UserCache::getGroupInfo(unsigned long gid) throw(Core::Exception) {
  getGroupList();

  boost::lock_guard<boost::shared_mutex> lock(mutex);

  if(!groups)
    throw groupException;

  std::map<unsigned long, GroupInfo>::const_iterator group = groups->find(gid);

  if(group == groups->end())
    throw Core::Exception(Core::Exception::NOT_FOUND);

  return boost::shared_ptr<GroupInfo>(new GroupInfo(group->second));
}

boost::shared_ptr<const GroupInfo> UserCache::getGroupInfoByName(const std::string &name) throw(Core::Exception) {
  getGroupList();

  boost::lock_guard<boost::shared_mutex> lock(mutex);

  if(!groups)
    throw groupException;

  std::map<std::string, unsigned long>::const_iterator gid = groupNames->find(name);
  if(gid == groupNames->end())
    throw Core::Exception(Core::Exception::NOT_FOUND);

  std::map<unsigned long, GroupInfo>::const_iterator group = groups->find(gid->second);

  return boost::shared_ptr<GroupInfo>(new GroupInfo(group->second));
}

boost::shared_ptr<const std::set<unsigned long> > UserCache::getGroupUserList(unsigned long gid) throw(Core::Exception) {
  getFullUserGroupList();

  boost::lock_guard<boost::shared_mutex> lock(mutex);

  if(!userGroups)
    throw userGroupException;

  std::pair<std::multimap<unsigned long, unsigned long>::iterator, std::multimap<unsigned long, unsigned long>::iterator> range = groupUsers->equal_range(gid);

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

  for(std::multimap<unsigned long, unsigned long>::iterator user = range.first; user != range.second; ++user)
    users->insert(user->second);

  return users;
}

boost::shared_ptr<const std::multimap<unsigned long, unsigned long> > UserCache::getFullUserGroupList() throw(Core::Exception) {
  boost::lock_guard<boost::shared_mutex> lock(mutex);

  if(userGroups) {
    application->log(Core::LoggerBase::USER, Core::LoggerBase::DEBUG, "Using cached user-group table");
    return userGroups;
  }
  else if(userGroupException) {
    application->log(Core::LoggerBase::USER, Core::LoggerBase::DEBUG, "Error cached");
    throw userGroupException;
  }
  try {
    userGroups = backend->getFullUserGroupList();

    groupUsers.reset(new std::multimap<unsigned long, unsigned long>);
    for(std::multimap<unsigned long, unsigned long>::const_iterator usergroup = userGroups->begin(); usergroup != userGroups->end(); ++usergroup)
      groupUsers->insert(std::make_pair(usergroup->second, usergroup->first));

    return userGroups;
  }
  catch(Core::Exception e) {
    userGroupException = e;
    throw userGroupException;
  }
}

}
}