import           Network.DNS.Message
import           Network.DNS.Named
import           Network.DNS.Named.Config
import           Network.DNS.Named.Responder
import           Network.DNS.Named.Zone
import           Network.Socket
import           System.IO.Unsafe

main :: IO ()
main = runNamed cnf zoneFor
    where
      cnf :: Config
      cnf = Config {
              cnfServerAddress = SockAddrInet 9090 iNADDR_ANY
            }

      zoneFor :: DomainName -> Maybe Zone
      zoneFor name
          | name `isInZone` zone = Just zone
          | otherwise            = Nothing

      zone :: Zone
      zone = Zone {
               zoneName            = mkDN "cielonegro.org."
             , zoneResponders      = [ wrapResponder responderA
                                     ]
             , zoneIsAuthoritative = True
             }

      responderA :: Responder A IN ()
      responderA = do name <- getQueryName
                      if name == mkDN "ns.cielonegro.org." then
                          respond ResourceRecord {
                                        rrName  = name
                                      , rrType  = A
                                      , rrClass = IN
                                      , rrTTL   = 9600
                                      , rrData  = inetAddr "127.0.0.1"
                                      }
                        else
                          fail "FIXME: we want to throw NameError but we can't for now"


inetAddr :: String -> HostAddress
inetAddr = unsafePerformIO . inet_addr