Actually properly implemented nick changing!

plugins/Nick.hs

@@ -15,15 +15,21 @@
 
 module Nick (plugin) where
 
+import qualified Data.Map as M
 import Control.Monad.State
 import IRCD.Types
+import IRCD.Env
+import IRCD.Clients
 
 plugin :: Plugin
 plugin = defaultPlugin {handlers=[CommandHandler "NICK" nickHandler]}
 
 nickHandler :: HandlerSpec
-nickHandler (ClientSrc client) (Message _ _ _ (nick:_)) = do
+nickHandler (ClientSrc client) (Message _ _ _ (nick':_)) = do
     nicks <- gets (byNick . envClients)
-    return [GenericAction (liftIO $ print nicks)]
-nickHandler (ClientSrc client) _ = return [GenericAction io]
-  where io = liftIO (putStrLn "No nickname given")
+    if nick' `M.member` nicks
+        then return [GenericAction $ liftIO (putStrLn "Nickname is already in use")]
+        else do
+            modify $ mapEnvClients (replaceClient client client {nick=Just nick'})
+            return [GenericAction $ liftIO (putStrLn ("NICK " ++ nick'))]
+nickHandler (ClientSrc client) _ = return [GenericAction $ liftIO (putStrLn "No nickname given")]

src/IRCD/Clients.hs

@@ -13,9 +13,7 @@
  - limitations under the License.
  -}
 
-module IRCD.Clients
-(firstAvailableID, insertClient, deleteClient, deleteClientByUid)
-where
+module IRCD.Clients where
 
 import Data.List (sort)
 import qualified Data.Map as M (insert, delete)
@@ -56,5 +54,8 @@ deleteClient client clients = clients
         Nothing    -> byNick clients
         Just nick' -> M.delete nick' (byNick clients)
 
+replaceClient :: Client -> Client -> Clients -> Clients
+replaceClient old new = insertClient new . deleteClient old
+
 deleteClientByUid :: Int -> Clients -> Clients
 deleteClientByUid uid' clients = clients {byUid = IM.delete uid' (byUid clients)}