rename modules for data types into Types/ directory

1 files changed, 76 insertions, 0 deletions

diff --git a/Types/Key.hs b/Types/Key.hs
new file mode 100644
index 000000000..1d9bf8e11
--- /dev/null
+++ b/Types/Key.hs
@@ -0,0 +1,76 @@
+{- git-annex Key data type
+ - 
+ - Most things should not need this, using Types instead
+ -
+ - Copyright 2011 Joey Hess <joey@kitenet.net>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Types.Key (
+	Key(..),
+	stubKey,
+	readKey,
+
+	prop_idempotent_key_read_show
+) where
+
+import Utility
+import System.Posix.Types
+
+{- A Key has a unique name, is associated with a key/value backend,
+ - and may contain other optional metadata. -}
+data Key = Key {
+	keyName :: String,
+	keyBackendName :: String,
+	keySize :: Maybe Integer,
+	keyMtime :: Maybe EpochTime
+} deriving (Eq, Ord)
+
+stubKey :: Key
+stubKey = Key {
+	keyName = "",
+	keyBackendName = "",
+	keySize = Nothing,
+	keyMtime = Nothing
+}
+
+fieldSep :: Char
+fieldSep = '-'
+
+{- Keys show as strings that are suitable for use as filenames.
+ - The name field is always shown last, separated by doubled fieldSeps,
+ - and is the only field allowed to contain the fieldSep. -}
+instance Show Key where
+	show Key { keyBackendName = b, keySize = s, keyMtime = m, keyName = n } =
+		b +++ ('s' ?: s) +++ ('m' ?: m) +++ (fieldSep : n)
+		where
+			"" +++ y = y
+			x +++ "" = x
+			x +++ y = x ++ fieldSep:y
+			c ?: (Just v) = c:(show v)
+			_ ?: _ = ""
+
+readKey :: String -> Maybe Key
+readKey s = if key == Just stubKey then Nothing else key
+	where
+		key = startbackend stubKey s
+
+		startbackend k v = sepfield k v addbackend
+		
+		sepfield k v a = case span (/= fieldSep) v of
+			(v', _:r) -> findfields r $ a k v'
+			_ -> Nothing
+
+		findfields (c:v) (Just k)
+			| c == fieldSep = Just $ k { keyName = v }
+			| otherwise = sepfield k v $ addfield c
+		findfields _ v = v
+
+		addbackend k v = Just k { keyBackendName = v }
+		addfield 's' k v = Just k { keySize = readMaybe v }
+		addfield 'm' k v = Just k { keyMtime = readMaybe v }
+		addfield _ _ _ = Nothing
+
+prop_idempotent_key_read_show :: Key -> Bool
+prop_idempotent_key_read_show k = Just k == (readKey $ show k)