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diff --git a/src/Propellor/Message.hs b/src/Propellor/Message.hs
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+{-# LANGUAGE PackageImports #-}
+
+module Propellor.Message where
+
+import System.Console.ANSI
+import System.IO
+import System.Log.Logger
+import "mtl" Control.Monad.Reader
+
+import Propellor.Types
+
+-- | Shows a message while performing an action, with a colored status
+-- display.
+actionMessage :: (MonadIO m, ActionResult r) => Desc -> m r -> m r
+actionMessage = actionMessage' Nothing
+
+-- | Shows a message while performing an action on a specified host,
+-- with a colored status display.
+actionMessageOn :: (MonadIO m, ActionResult r) => HostName -> Desc -> m r -> m r
+actionMessageOn = actionMessage' . Just
+
+actionMessage' :: (MonadIO m, ActionResult r) => Maybe HostName -> Desc -> m r -> m r
+actionMessage' mhn desc a = do
+	liftIO $ do
+		setTitle $ "propellor: " ++ desc
+		hFlush stdout
+
+	r <- a
+
+	liftIO $ do
+		setTitle "propellor: running"
+		showhn mhn
+		putStr $ desc ++ " ... "
+		let (msg, intensity, color) = getActionResult r
+		colorLine intensity color msg
+		hFlush stdout
+
+	return r
+  where
+	showhn Nothing = return ()
+	showhn (Just hn) = do
+		setSGR [SetColor Foreground Dull Cyan]
+		putStr (hn ++ " ")
+		setSGR []
+
+warningMessage :: MonadIO m => String -> m ()
+warningMessage s = liftIO $ colorLine Vivid Magenta $ "** warning: " ++ s
+
+colorLine :: ColorIntensity -> Color -> String -> IO ()
+colorLine intensity color msg = do
+	setSGR [SetColor Foreground intensity color]
+	putStr msg
+	setSGR []
+	-- Note this comes after the color is reset, so that
+	-- the color set and reset happen in the same line.
+	putStrLn ""
+	hFlush stdout
+
+errorMessage :: String -> IO a
+errorMessage s = do
+	liftIO $ colorLine Vivid Red $ "** error: " ++ s
+	error "Cannot continue!"
+
+-- | Causes a debug message to be displayed when PROPELLOR_DEBUG=1
+debug :: [String] -> IO ()
+debug = debugM "propellor" . unwords