add alerts to DaemonStatus

Assistant/Alert.hs

@@ -0,0 +1,25 @@
+{- git-annex assistant alerts
+ -
+ - Copyright 2012 Joey Hess <joey@kitenet.net>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE RankNTypes #-}
+
+module Assistant.Alert where
+
+import Yesod
+
+type Widget = forall sub master. GWidget sub master ()
+
+{- Different classes of alerts are displayed differently. -}
+data AlertClass = Activity | Warning | Error | Message
+
+{- An alert can be a simple message, or a Yesod Widget -}
+data AlertMessage = StringAlert String | WidgetAlert Widget
+
+data Alert = Alert
+	{ alertClass :: AlertClass
+	, alertMessage :: AlertMessage
+	}