{-# OPTIONS_GHC -fno-warn-orphans #-}
{-# LANGUAGE OverloadedStrings #-}

module Serialization where

import Types
import Raaz.Core.Encode
import qualified Data.ByteString as B
import qualified Data.ByteString.Char8 as B8
import Data.Monoid
import Data.Word
import Text.Read

-- TODO
-- | An EncryptedSecretKey is serialized as first a md5sum of the rest
-- of the content, and then a SelfDescription EncryptedSecretKey,
-- and finally the 
--instance Encodable EncryptedSecretKey where
--	toByteString (EncryptedSecretKey b _) = b
--	fromByteString b = 

-- | A KeyIdent is serialized in the form "keytype name".
-- For example "gpg Joey Hess"
instance Encodable KeyIdent where
	toByteString (KeyIdent (KeyType t) (Name n)) =
		t <> B.singleton sepChar <> n
	fromByteString b = case B.break (== sepChar) b of
		(t, n)
			| B.null n -> Nothing
			| otherwise -> Just $
				KeyIdent (KeyType t) (Name (B.drop 1 n))

-- | An ObjectIdent is serialied in the form "shardnum keytype name"
-- For example "1 gpg Joey Hess"
instance Encodable ObjectIdent where
	toByteString (ObjectIdent (ShardNum n) keyident) =
		B8.pack (show n) <> B.singleton sepChar <> toByteString keyident
	fromByteString b = case B.break (== sepChar) b of
		(ns, rest)
			| B.null ns -> Nothing
			| otherwise -> do
				keyident <- fromByteString (B.drop 1 rest)
				n <- readMaybe (B8.unpack ns)
				return $ ObjectIdent (ShardNum n) keyident

sepChar :: Word8
sepChar = 32