module Rattletrap.Utility where

import qualified Data.Bits as Bits
import qualified Data.ByteString.Lazy as ByteString
import qualified Data.ByteString.Lazy.Char8 as ByteString8
import qualified Data.Text as Text
import qualified Data.Word as Word

encodeLatin1 :: Text.Text -> ByteString.ByteString
encodeLatin1 text = ByteString8.pack (Text.unpack text)

padBytes :: Integral a => a -> ByteString.ByteString -> ByteString.ByteString
padBytes size bytes =
  ByteString.concat
    [ bytes
    , ByteString.replicate (fromIntegral size - ByteString.length bytes) 0x00
    ]

reverseByte :: Word.Word8 -> Word.Word8
reverseByte byte =
  Bits.shiftR (byte Bits..&. Bits.bit 7) 7 +
  Bits.shiftR (byte Bits..&. Bits.bit 6) 5 +
  Bits.shiftR (byte Bits..&. Bits.bit 5) 3 +
  Bits.shiftR (byte Bits..&. Bits.bit 4) 1 +
  Bits.shiftL (byte Bits..&. Bits.bit 3) 1 +
  Bits.shiftL (byte Bits..&. Bits.bit 2) 3 +
  Bits.shiftL (byte Bits..&. Bits.bit 1) 5 +
  Bits.shiftL (byte Bits..&. Bits.bit 0) 7

reverseBytes :: ByteString.ByteString -> ByteString.ByteString
reverseBytes = ByteString.map reverseByte