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

main :: IO ()
main = runNamed cnf (return . findZone)
    where
      cnf :: Config
      cnf = Config {
              cnfServerAddress = SockAddrInet 9090 iNADDR_ANY
            , cnfAllowTransfer = True
            }

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

      zone :: Zone
      zone = Zone {
               zoneName = mkDN "cielonegro.org."
             , zoneSOA  = Just SOAFields {
                            soaMasterNameServer   = mkDN "ns.cielonegro.org."
                          , soaResponsibleMailbox = mkDN "root.ns.cielonegro.org."
                          , soaSerialNumber       = 2008022148
                          , soaRefreshInterval    = 3600
                          , soaRetryInterval      = 900
                          , soaExpirationLimit    = 3600000
                          , soaMinimumTTL         = 3600
                          }
             , zoneRecordNames = return [ mkDN "ns.cielonegro.org."
                                        , mkDN "www.cielonegro.org."
                                        , mkDN "git.cielonegro.org."
                                        ]
             , zoneResponder   = return . responder
             }

      responder :: DomainName -> [SomeRR]
      responder name
          | name == mkDN "ns.cielonegro.org."
              = [ wrapRecord ResourceRecord {
                                   rrName  = name
                                 , rrType  = A
                                 , rrClass = IN
                                 , rrTTL   = 9600
                                 , rrData  = inetAddr "127.0.0.1"
                                 }
                ]
          | name == mkDN "www.cielonegro.org."
              = [ wrapRecord ResourceRecord {
                                   rrName  = name
                                 , rrType  = A
                                 , rrClass = IN
                                 , rrTTL   = 9600
                                 , rrData  = inetAddr "127.0.0.2"
                                 }
                ]
          | name == mkDN "git.cielonegro.org."
              = [ wrapRecord ResourceRecord {
                                   rrName  = name
                                 , rrType  = CNAME
                                 , rrClass = IN
                                 , rrTTL   = 9600
                                 , rrData  = mkDN "www.cielonegro.org."
                                 }
                ]
          | otherwise
              = [] -- This means NXDOMAIN.


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