[Haskell-cafe] My piece of an IRC bot

[ihope]

Today I started on a simple IRC bot framework thingy. I decided to
post the source code here so people can look at it and tell me what
the heck I did wrong :-P

> module IRC where
>
> import Control.Monad.State
> import System.IO
> import Network
>
> {----------------------}{------------------------------------------------------}
>
> data IRCMessage         = IRCMessage (Maybe String) String [String]
>
> type IRCBot a           = IRCMessage -> State a [IRCMessage]
> type IRCConnection a    = IRCBot a -> IO ()
>
> ircConnect              :: String -> Integer -> a -> IRCConnection a
>
> ircConnect server port
>               state bot = withSocketsDo (do
>   connection <- connectTo server (PortNumber (fromInteger port))
>  ircLoop connection state bot)
>
> ircLoop connection state
>                     bot = do
>   eof <- hIsEOF connection
>   if eof then hWaitForInput connection 500 >> return () else do
>     message <- hGetLine connection
>     hPutStr connection (fst (runState (bot (ircParseMessage message)) state) >>=
>                                                                   decodeMessage)
>     ircLoop connection (snd (runState (bot (ircParseMessage message)) state))
>                                                                              bot
>
> -- Oh noes. Let's hope we'll never, ever have to read that ;-)
>
> {-End I/O capable code-}{------------------------------------------------------}
>
> ircParseMessage x       = let rx       = filter (/='\r') x
>                               (p:u:us) = words rx in
>                           if (head p) == ':' then IRCMessage (Just p) u
>                                                              (ircParseParams us)
>                           else IRCMessage Nothing p (ircParseParams (u:us))
>
> ircParseParams (x:xs)   = if head x == ':' then [unwords (x:xs)]
>                           else x : ircParseParams xs
>
> decodeMessage (IRCMessage
>  Nothing command params)= (command ++ ' ' : unwords (init params) ++ ' ' :
>                                                             (':' : last params))
>
> decodeMessage
>  (IRCMessage (Just
>  prefix) command params)= ((':' : prefix) ++ ' ' : command ++ ' ' : unwords
>                                            (init params) ++ (':' : last params))
>
> {-Thus ends the IRCbot-}{------------------------------------------------------}

The very simple bot I've been trying to run with it:

> module Main where
>
> import IRC
> import Control.Monad.State
>
> {----------------------}{------------------------------------------------------}
>
> main                    = ircConnect "brown.freenode.net" 6667 False bot
>
> bot _                   = State (\x -> if x then ([],True) else (
>                           [IRCMessage Nothing "NICK" ["EagleBot"],
>                            IRCMessage Nothing "USER" ["EagleBot", "Null",
>                                                             "Null", "EagleBot"],
>                            IRCMessage Nothing "PRIVMSG" ["NickServ",
>                                                         "IDENTIFY censored"],
>                            IRCMessage Nothing "JOIN" ["#esoteric"]],True))