add JSON serialization

Fairly straightforward, but did have to decide how to encode all the
ByteStrings, since they are not necessarily utf-8. Used base64.

This commit was sponsored by Henrik Riomar on Patreon.

1 files changed, 10 insertions, 7 deletions

diff --git a/Hash.hs b/Hash.hs
index eca00e4..4174d5f 100644
--- a/Hash.hs
+++ b/Hash.hs
@@ -8,19 +8,22 @@ import qualified Data.ByteString as B
 import qualified Data.ByteString.Char8 as C8
 import qualified Crypto.Hash as H
 
--- | Encode a hash pointer using base16 format.
-encodeHashPointer :: HashPointer -> B.ByteString
-encodeHashPointer (HashPointer d) = C8.pack (show d)
-
 class Hashable a where
 	hash :: a -> HashPointer
 
 instance Hashable B.ByteString where
-	hash = HashPointer . H.hash
+	-- Encodes the SHA256 using base16 format
+	hash = HashPointer SHA256 . Val . C8.pack . show . sha256
+
+instance Hashable Val where
+	hash (Val v) = hash v
+
+sha256 :: B.ByteString -> H.Digest H.SHA256
+sha256 = H.hash
 
--- | Hash the concacenation of the hashes, encoding them in base16 format.
+-- | Hash the concacenation of the hashes.
 instance Hashable [HashPointer] where
-	hash = hash . B.concat . map encodeHashPointer
+	hash = hash . B.concat . map (val . hashValue)
 
 instance Hashable a => Hashable (Activity a) where
 	hash (Activity a p s) = hash [hash a, p, hash s]