map $host $host_dir {
  hostnames;
  ~(?:(?<sssssd>[a-z0-9-]+)\.)(?:(?<ssssd>[a-z0-9-]+)\.)(?:(?<sssd>[a-z0-9-]+)\.)(?:(?<ssd>[a-z0-9-]+)\.)(?:(?<sd>[a-z0-9-]+)\.)(?<dom>[a-z0-9-]+)\.(?<tld>[a-z0-9-]+)$ ${tld}/${dom}/${sd}/${ssd}/${sssd}/${ssssd}/${sssssd};
  ~(?:(?<ssssd>[a-z0-9-]+)\.)(?:(?<sssd>[a-z0-9-]+)\.)(?:(?<ssd>[a-z0-9-]+)\.)(?:(?<sd>[a-z0-9-]+)\.)(?<dom>[a-z0-9-]+)\.(?<tld>[a-z0-9-]+)$ ${tld}/${dom}/${sd}/${ssd}/${sssd}/${ssssd};
  ~(?:(?<sssd>[a-z0-9-]+)\.)(?:(?<ssd>[a-z0-9-]+)\.)(?:(?<sd>[a-z0-9-]+)\.)(?<dom>[a-z0-9-]+)\.(?<tld>[a-z0-9-]+)$ ${tld}/${dom}/${sd}/${ssd}/${sssd};
  ~(?:(?<ssd>[a-z0-9-]+)\.)(?:(?<sd>[a-z0-9-]+)\.)(?<dom>[a-z0-9-]+)\.(?<tld>[a-z0-9-]+)$ ${tld}/${dom}/${sd}/${ssd};
  ~(?:(?<sd>[a-z0-9-]+)\.)(?<dom>[a-z0-9-]+)\.(?<tld>[a-z0-9-]+)$ ${tld}/${dom}/${sd};
  ~(?<dom>[a-z0-9-]+)\.(?<tld>[a-z0-9-]+)$ ${tld}/${dom};
}