module Text.XXD where

import qualified Data.ByteString.Base16 as Base16
import Data.ByteString (ByteString)
import qualified Data.ByteString as B
import Data.Word
import Data.Bits
import Data.Char
import Text.Printf

nibble :: Word8 -> Char
nibble b = intToDigit (fromIntegral (b .&. 0x0F))

xxd :: Int -> ByteString -> [String]
xxd offset bs | B.null bs = []
xxd offset bs             = printf "%03x: %s" offset ds : xxd (offset + B.length xs) bs'
 where
    ds = unwords $ map (\byte -> [nibble (byte `shiftR` 4), nibble byte])
                 $ B.unpack xs
    (xs,bs') = B.splitAt 16 bs

{-
main = do
    bs <- B.getContents
    mapM_ putStrLn $ xxd 0 bs
    -}