almost able to get files from remotes now!

UUID.hs

@@ -9,12 +9,16 @@ module UUID (
 	UUID,
 	getUUID,
 	prepUUID,
-	genUUID
+	genUUID,
+	reposByUUID
 ) where
 
+import Maybe
+import List
 import System.Cmd.Utils
 import System.IO
 import GitRepo
+import Types
 
 type UUID = String
 
@@ -26,17 +30,34 @@ genUUID :: IO UUID
 genUUID = do
 	pOpen ReadFromPipe "uuid" ["-m"] $ \h -> hGetLine h
 
-{- Looks up a repo's UUID -}
-getUUID :: GitRepo -> UUID
-getUUID repo = gitConfig repo "annex.uuid" ""
+{- Looks up a repo's UUID. May return "" if none is known.
+ -
+ - UUIDs of remotes are cached in git config, using keys named
+ - remote.<name>.annex-uuid
+ -
+ - -}
+getUUID :: State -> GitRepo -> UUID
+getUUID s r = 
+	if ("" /= getUUID' r)
+		then getUUID' r
+		else cached s r
+	where
+		cached s r = gitConfig (repo s) (configkey r) ""
+		configkey r = "remote." ++ (gitRepoRemoteName r) ++ ".annex-uuid"
+getUUID' r = gitConfig r "annex.uuid" ""
 
 {- Make sure that the repo has an annex.uuid setting. -}
 prepUUID :: GitRepo -> IO GitRepo
 prepUUID repo =
-	if ("" == getUUID repo)
+	if ("" == getUUID' repo)
 		then do
 			uuid <- genUUID
 			gitRun repo ["config", configkey, uuid]
 			-- return new repo with updated config
 			gitConfigRead repo
 		else return repo
+
+{- Filters a list of repos to ones that have listed UUIDs. -}
+reposByUUID :: State -> [GitRepo] -> [UUID] -> [GitRepo]
+reposByUUID state repos uuids =
+	filter (\r -> isJust $ elemIndex (getUUID state r) uuids) repos