add post-repair actions

Assistant/Types/RepoProblem.hs

@@ -1,4 +1,4 @@
-{- git-annex assistant remote problem detection
+{- git-annex assistant repository problem tracking
  -
  - Copyright 2013 Joey Hess <joey@kitenet.net>
  -
@@ -11,8 +11,18 @@ import Types
 import Utility.TList
 
 import Control.Concurrent.STM
+import Data.Function
 
-type RepoProblemChan = TList UUID
+data RepoProblem = RepoProblem
+	{ problemUUID :: UUID
+	, afterFix :: IO ()
+	}
+
+{- The afterFix actions are assumed to all be equivilant. -}
+sameRepoProblem :: RepoProblem -> RepoProblem -> Bool
+sameRepoProblem = (==) `on` problemUUID
+
+type RepoProblemChan = TList RepoProblem
 
 newRepoProblemChan :: IO RepoProblemChan
 newRepoProblemChan = atomically newTList