/*
 * UserBackendHome.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 Lesser 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License along
 * with this program. If not, see <http://www.gnu.org/licenses/>.
 */

#include "UserBackendHome.h"
#include <Core/ConfigEntry.h>
#include <Core/ConfigManager.h>

#include <boost/filesystem.hpp>

#include <unistd.h>
#include <sys/stat.h>
#include <sys/types.h>

namespace Mad {
namespace Modules {
namespace UserBackendHome {

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

  if(entry[0].getKey().matches("UserBackendHome")) {
    if(entry[1].getKey().matches("Skeleton")) {
      if(entry[2].empty())
        skeleton = entry[1][0];
    }
    else if(entry[1].getKey().matches("HomeDir")) {
      if(entry[2].empty())
        homeDir = entry[1][0];
    }
    else if(entry[1].getKey().matches("DirMode")) {
      if(entry[2].empty()) {
        if(entry[1][0].empty()) {
          dirMode = 0755;
        }
        else {
          char *endptr;
          unsigned long val = std::strtoul(entry[1][0].c_str(), &endptr, 8);
          if(*endptr || val > 07777) {
            application->logf(Core::LoggerBase::WARNING, "UserBackendHome: Invalid configuration: DirMode '%s'", entry[1][0].c_str());
          }
          else {
            dirMode = val;
          }
        }
      }
    }
    else if(!entry[1].empty())
      return false;

    return true;
  }

  return false;
}

void UserBackendHome::setOwnerAndCopyMode(const std::string &source, const std::string &dest, const Common::UserInfo &userInfo, bool isSymlink) {
  if((isSymlink ? lchown : chown)(dest.c_str(), (uid_t)userInfo.getUid(), (gid_t)userInfo.getGid()) != 0) {
    // TODO Error
  }

  struct stat st;
  if((isSymlink ? lstat : stat)(source.c_str(), &st) == 0) {
    if((isSymlink ? lchmod : chmod)(dest.c_str(), st.st_mode & (S_IRWXU|S_IRWXG|S_IRWXO)) != 0) {
      // TODO Error
    }
  }
}

void UserBackendHome::migrateOwner(const std::string &path, const Common::UserInfo &oldUserInfo, const Common::UserInfo &userInfo, bool isSymlink) {
  struct stat st;
  if((isSymlink ? lstat : stat)(path.c_str(), &st) != 0) {
    // TODO Error
    return;
  }

  uid_t uid = -1;
  gid_t gid = -1;

  if(st.st_uid == oldUserInfo.getUid())
    uid = (uid_t)userInfo.getUid();

  if(st.st_gid == oldUserInfo.getGid())
    gid = (gid_t)userInfo.getGid();

  if(uid != (uid_t)-1 || gid != (gid_t)-1) {
    if((isSymlink ? lchown : chown)(path.c_str(), uid, gid) != 0) {
      // TODO Error
    }
  }
}

void UserBackendHome::addUser(const Common::UserInfo &userInfo) throw(Core::Exception) {
  boost::filesystem::path path(homeDir);
  path /= userInfo.getUsername();

  boost::filesystem::create_directories(path);

  std::string nativePath = path.directory_string();
  if(chown(nativePath.c_str(), (uid_t)userInfo.getUid(), (gid_t)userInfo.getGid()) != 0) {
    // TODO Error
  }

  if(chmod(nativePath.c_str(), (mode_t)dirMode)) {
    // TODO Error
  }

  boost::filesystem::path skeletonPath(skeleton);
  if(!boost::filesystem::is_directory(skeletonPath))
    return;

  boost::filesystem::path oldPath = boost::filesystem::current_path();
  boost::filesystem::current_path(skeletonPath);

  boost::filesystem::recursive_directory_iterator end;

  for(boost::filesystem::recursive_directory_iterator it("."); it != end; ++it) {
    boost::filesystem::path source = it->path();
    boost::filesystem::path dest = path / source;

    try {
      if(boost::filesystem::is_symlink(it->symlink_status())) {
        it.no_push();

        std::string sourceStr = source.file_string();

        char link[PATH_MAX];
        int ret = ::readlink(sourceStr.c_str(), link, PATH_MAX);
        if(ret <= 0)
          continue;

        boost::filesystem::create_symlink(boost::filesystem::path(std::string(link, ret)), dest);
        setOwnerAndCopyMode(sourceStr, dest.file_string(), userInfo, true);
      }
      else if(boost::filesystem::is_directory(it->status())) {
        boost::filesystem::create_directory(dest);
        setOwnerAndCopyMode(source.directory_string(), dest.directory_string(), userInfo, false);
      }
      else {
        boost::filesystem::copy_file(source, dest);
        setOwnerAndCopyMode(source.file_string(), dest.file_string(), userInfo, false);
      }
    }
    catch(...) {}
  }

  boost::filesystem::current_path(oldPath);
}

void UserBackendHome::updateUser(const Common::UserInfo &oldUserInfo, const Common::UserInfo &userInfo) throw(Core::Exception) {
  boost::filesystem::path oldPath(homeDir);
  oldPath /= oldUserInfo.getUsername();

  boost::filesystem::path path(homeDir);
  path /= userInfo.getUsername();

  if(oldPath != path) {
    try {
      boost::filesystem::rename(oldPath, path);
    }
    catch(...) {
      return;
    }
  }

  if(oldUserInfo.getUid() == userInfo.getUid() && oldUserInfo.getGid() == userInfo.getGid())
    return;

  std::string nativePath = path.directory_string();
  if(chown(nativePath.c_str(), (uid_t)userInfo.getUid(), (gid_t)userInfo.getGid()) != 0) {
    // TODO Error
  }

  boost::filesystem::recursive_directory_iterator end;

  for(boost::filesystem::recursive_directory_iterator it(path); it != end; ++it) {
    if(boost::filesystem::is_symlink(it->symlink_status())) {
      it.no_push();

      migrateOwner(it->path().file_string(), oldUserInfo, userInfo, true);
    }
    else if(boost::filesystem::is_directory(it->status())) {
      migrateOwner(it->path().directory_string(), oldUserInfo, userInfo, false);
    }
    else {
      migrateOwner(it->path().file_string(), oldUserInfo, userInfo, false);
    }
  }
}

void UserBackendHome::deleteUser(const Common::UserInfo &userInfo) throw(Core::Exception) {
  boost::filesystem::path path(homeDir);
  path /= userInfo.getUsername();

  boost::filesystem::remove_all(path);
}

}
}
}