Types.hs

module Conjure.Protocol.PWP.Types where

import qualified Data.ByteString as BS
import Data.ByteString (ByteString)

import Data.Word

newtype PeerId = PeerId {unPeerId :: ByteString} deriving (Eq,Ord)

instance Show PeerId where
    showsPrec n (PeerId peerId) = showsPrec n peerId

data Handshake
    = Handshake
    { hsInfoHash :: ByteString
    , hsPeerId   :: PeerId
    }

-- | Message datatype. Should be revamped to use packed strings.
data Message 
    = KeepAlive
    | Choke     
    | Unchoke    
    | Interested 
    | NotInterested
    | Have !Int     -- ^ Note: this is not trustworthy (could claim pieces
                    -- it doesn't have that we will never want, could leave
                    -- out pieces we don't want that it has)
    | BitField ByteString -- ^ which Pieces this peer boasts to have

      -- | Request for a block of data. A bit complicated. See spec for detals.
    | Request { msgIndex    :: !Int, -- ^ Piece index
                msgBegin    :: !Int,      -- ^ Byte offset within piece
                msgLength   :: !Int       -- ^ Length in bytes, normally 2^14
              }
      
      -- | Such a block of data.
    | RequestedPiece
      { msgIndex    :: !Int        -- ^ Piece index
      , msgBegin    :: !Int        -- ^ Byte offset within piece
      , msgBlock    :: ByteString
      }
 
      -- | Cancel a request.
    | Cancel { msgIndex    :: !Int, -- ^ Piece index
               msgBegin    :: !Int,      -- ^ Byte offset within piece
               msgLength   :: !Int       -- ^ Length in bytes, normally 2^14
             }

      -- | Not a real message type, holds the id of an
      -- unknown message type
    | Unknown !Word8
      deriving (Eq,Show)