module IPS.Types
  (Patch, Chunk (..), ChunkBody (..),
   Word8, Word16, Word24,
   Bytes, makeBytes)
where

import Data.ByteString (ByteString)
import qualified Data.ByteString as ByteString
import Data.Vector (Vector)
import qualified Data.Vector.Storable as S
import Data.Word
import IPS.Word24


type Patch = Vector Chunk

data Chunk =
  Chunk {
    offset :: {-# UNPACK #-} !Word24,
    body   :: !ChunkBody
  }
  deriving (Show, Eq)

data ChunkBody =
    Normal {-# UNPACK #-} !Bytes
  | RLE {
      size   :: {-# UNPACK #-} !Word16,
      value  :: {-# UNPACK #-} !Word8
    }
  deriving (Show, Eq)

type Bytes = S.Vector Word8

makeBytes :: ByteString -> Bytes
makeBytes bs = S.generate (ByteString.length bs) (ByteString.index bs)