1 files changed, 24 insertions, 0 deletions
diff --git a/src/Erebos/UUID.hs b/src/Erebos/UUID.hs
new file mode 100644
index 0000000..128d450
--- /dev/null
+++ b/src/Erebos/UUID.hs
@@ -0,0 +1,24 @@
+module Erebos.UUID (
+    UUID,
+    toString, fromString,
+    toText, fromText,
+    toASCIIBytes, fromASCIIBytes,
+    nextRandom,
+) where
+
+import Crypto.Random.Entropy
+
+import Data.Bits
+import Data.ByteString qualified as BS
+import Data.ByteString.Lazy qualified as BSL
+import Data.Maybe
+import Data.UUID.Types
+
+nextRandom :: IO UUID
+nextRandom = do
+    [ b0, b1, b2, b3, b4, b5, b6, b7, b8, b9, ba, bb, bc, bd, be, bf ]
+        <- BS.unpack <$> getEntropy 16
+    let version = 4
+        b6' = b6 .&. 0x0f .|. (version `shiftL` 4)
+        b8' = b8 .&. 0x3f .|. 0x80
+    return $ fromJust $ fromByteString $ BSL.pack [ b0, b1, b2, b3, b4, b5, b6', b7, b8', b9, ba, bb, bc, bd, be, bf ]