import Data.ByteString (ByteString, unpack, concat, hGet, hPut, singleton)
import Data.ByteString.Char8 (replicate, pack)
import Network (connectTo, PortID(..))
+import Data.Binary (Binary(..))
+import Data.Binary.Put (putWord32be, putWord8)
type ID = String
type IP = String
type Port = Integer
-data PeerState = PeerState { am_choking :: Bool
+data PeerState = PeerState { handle :: Handle
+ , am_choking :: Bool
, am_interested :: Bool
, peer_choking :: Bool
, peer_interested :: Bool }
+-- Maintain info on every piece and the current state of it.
+-- should probably be a TVar.
+type Pieces = [PieceData]
+
+data PieceState = Pending
+ | InProgress
+ | Have
+ deriving (Show)
+
+data PieceData = PieceData { index :: Int -- ^ Piece number
+ , peers :: [Peer] -- ^ list of peers who have this piece
+ , state :: PieceState } -- ^ state of the piece from download perspective.
+
-- | Peer is a PeerID, IP address, port tuple
data Peer = Peer ID IP Port
deriving (Show, Eq)
-data Msg = HandShakeMsg ByteString ID
- | KeepAliveMsg
- | ChokeMsg
- | UnChokeMsg
- | InterestedMsg
- | NotInterestedMsg
- | HaveMsg Integer
- | BitFieldMsg Integer
- | RequestMsg Integer Integer Integer
- | PieceMsg Integer Integer Integer
- | CancelMsg Integer Integer Integer
- | PortMsg Port
- deriving (Show)
+data PeerMsg = KeepAliveMsg
+ | ChokeMsg
+ | UnChokeMsg
+ | InterestedMsg
+ | NotInterestedMsg
+ | HaveMsg Integer
+ | BitFieldMsg ByteString
+ | RequestMsg Integer Integer Integer
+ | PieceMsg Integer Integer ByteString
+ | CancelMsg Integer Integer Integer
+ | PortMsg Port
+ deriving (Show)
genHandShakeMsg :: ByteString -> String -> ByteString
genHandShakeMsg infoHash peer_id = concat [pstrlen, pstr, reserved, infoHash, peerID]
reserved = replicate 8 '\0'
peerID = pack peer_id
-handShake :: Peer -> ByteString -> String -> IO ByteString
+handShake :: Peer -> ByteString -> String -> IO Handle
handShake (Peer _ ip port) infoHash peerid = do
let hs = genHandShakeMsg infoHash peerid
handle <- connectTo ip (PortNumber (fromIntegral port))
rlenBS <- hGet handle 1
let rlen = fromIntegral $ (unpack rlenBS) !! 0
hGet handle rlen
+ return handle
+
+instance Binary PeerMsg where
+ put msg = case msg of
+ KeepAliveMsg -> putWord32be 0
+ ChokeMsg -> do putWord32be 1
+ putWord8 0
+ UnChokeMsg -> do putWord32be 1
+ putWord8 1
+ InterestedMsg -> do putWord32be 1
+ putWord8 2
+ NotInterestedMsg -> do putWord32be 1
+ putWord8 3
+ HaveMsg index -> do putWord32be 5
+ putWord8 4
+ putWord32be (fromIntegral index)
+ BitFieldMsg bf -> do putWord32be $ fromIntegral (1 + bfListLen)
+ putWord8 5
+ mapM_ putWord8 bfList
+ where bfList = unpack bf
+ bfListLen = length bfList
+ RequestMsg i o l -> do putWord32be 13
+ putWord8 6
+ putWord32be (fromIntegral i)
+ putWord32be (fromIntegral o)
+ putWord32be (fromIntegral l)
+ PieceMsg i o b -> do putWord32be $ fromIntegral (9 + blocklen)
+ putWord8 7
+ putWord32be (fromIntegral i)
+ putWord32be (fromIntegral o)
+ mapM_ putWord8 blockList
+ where blockList = unpack b
+ blocklen = length blockList
+ CancelMsg i o l -> undefined
+ PortMsg p -> undefined
+ get = undefined
--- sendMsg :: Peer -> Handle -> PeerMsg -> IO ()
+-- loop1 :: shake hands with all peers, find out the pieces they have, form PieceData.
-- recvMsg :: Peer -> Handle -> Msg