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Version.hs

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+{- git-annex repository versioning
+ -
+ - Copyright 2010 Joey Hess <joey@kitenet.net>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Version where
+
+import Control.Monad.State (liftIO)
+import System.Directory
+
+import Types
+import qualified Annex
+import qualified GitRepo as Git
+import Locations
+
+currentVersion :: String
+currentVersion = "1"
+
+versionField :: String
+versionField = "annex.version"
+
+getVersion :: Annex (Maybe String)
+getVersion = do
+	g <- Annex.gitRepo
+	let v = Git.configGet g versionField ""
+	if (not $ null v)
+		then return $ Just v
+		else do
+			-- version 0 was not recorded in .git/config;
+			-- such a repo should have an annexDir
+			d <- liftIO $ doesDirectoryExist $ annexDir g
+			if (d)
+				then return $ Just "0"
+				else return Nothing -- no version yet
+
+setVersion :: Annex ()
+setVersion = Annex.setConfig versionField currentVersion