\begin{code}
 
module Main (main) where  

import Distributed
import System.IO
 
data Msg = Alloc String Pid | Value String Pid | Lookup String Pid | Down Pid |
 	   Allocated | Free | IsValue (Maybe String) | Connect Pid | Shutdown
  deriving (Show, Read)

instance Serialize Msg

destNode = "DB-Server"
main = start (do 
  me <- self
  destHost <- proc $ myGetVarDefault "DBSERVER" "localhost"
  remoteSend (Hostname destHost) (Nodename destNode) "dataBase" (Connect me)
  -- (PidName (Hostname destHost, Nodename destNode,"dataBase")) <!> (Connect me)
  receive (\v -> case v of
    Connect db -> do
      nolink <- proc $ myGetVar "DBNOLINK"
      case nolink of
        Just _ -> return ()
        Nothing -> linkMeWith db
      client db)
 ) ""

client :: Pid -> DIO Msg ()
client pid = do
  str <- proc $ do
    putStr "(i)nsert / (l)ookup > "
    hFlush stdout
    getLine
  me <- self
  case str of
    "i" -> do 
      proc $ putStr "Key > "
      proc $ hFlush stdout
      key <- proc(getLine)
      pid <!> (Alloc key me)
      receive (\v -> case v of
        Free -> do
          proc $ putStr "Value > "
          proc $ hFlush stdout
	  v <- proc$ getLine
	  pid <!> (Value v me)
	  client pid
        Allocated -> do
          proc $ putStrLn "Key is allocated > "
	  client pid
        Down _ -> do
          proc $ putStrLn "Server went down"
	  halt) 
    "l" -> do 
      proc $ putStr "Key > "
      proc $ hFlush stdout
      key <- proc $ getLine
      pid <!> (Lookup key me)
      receive (\v -> case v of
        IsValue mStr -> do
	  proc $ putStr "Value > " 
	  proc $ putStrLn (show mStr)
	  client pid
	Down _ -> do
	  proc $ putStrLn "Server went down"
	  halt)
    "q" -> halt
    "Q" -> do
      pid <!> Shutdown
      halt
    _   -> client pid
\end{code}