refactor PeerState: Add connection handle to be part of peerstate

[functorrent.git] / src / FuncTorrent / Peer.hs

diff --git a/src/FuncTorrent/Peer.hs b/src/FuncTorrent/Peer.hs
index e0a27c9f6a7a500efd2b2fb0a49fff84b15fdc50..0d70f9f391b385e241ddc88f1dde16902b4dec34 100644 (file)
--- a/src/FuncTorrent/Peer.hs
+++ b/src/FuncTorrent/Peer.hs
@@ -8,17 +8,17 @@ import Prelude hiding (lookup, concat, replicate, splitAt, empty, writeFile)
 
 import System.IO (Handle, BufferMode(..), hSetBuffering)
 import Data.ByteString (ByteString, pack, unpack, concat, hGet, hPut, singleton, writeFile)
-import Data.ByteString.Lazy (fromStrict, fromChunks)
+import Data.ByteString.Lazy (fromStrict, fromChunks, toStrict)
 import qualified Data.ByteString.Char8 as BC (replicate, pack, length)
 import Network (connectTo, PortID(..))
-import Data.Binary (Binary(..), decode)
+import Data.Binary (Binary(..), decode, encode)
 import Data.Binary.Put (putWord32be, putWord16be, putWord8)
 import Data.Binary.Get (getWord32be, getWord16be, getWord8, runGet)
 import Control.Monad (replicateM, liftM, forever)
 import Control.Applicative ((<$>), liftA3)
 import Data.Bits
 import Data.Word (Word8)
-import Data.Map (Map(..), fromList)
+import Data.Map (Map(..), fromList, (!))
 
 import FuncTorrent.Metainfo (Info(..), Metainfo(..))
 import FuncTorrent.Utils (splitN)
@@ -27,11 +27,13 @@ type ID = String
 type IP = String
 type Port = Integer
 
+-- PeerState is a misnomer
 data PeerState = PeerState { handle :: Handle
-                           , am_choking :: Bool
-                           , am_interested :: Bool
-                           , peer_choking :: Bool
-                           , peer_interested :: Bool}
+                           , peer :: Peer
+                           , meChoking :: Bool
+                           , meInterested :: Bool
+                           , heChoking :: Bool
+                           , heInterested :: Bool}
 
 -- Maintain info on every piece and the current state of it.
 -- should probably be a TVar.
@@ -40,7 +42,7 @@ type Pieces = [PieceData]
 data PieceDlState = Pending
                   | InProgress
                   | Have
-                  deriving (Show)
+                  deriving (Show, Eq)
 
 -- todo - map with index to a new data structure (peers who have that piece amd state)
 data PieceData = PieceData { peers :: [Peer]        -- ^ list of peers who have this piece
@@ -69,13 +71,17 @@ data PeerMsg = KeepAliveMsg
 
 -- Make the initial Piece map, with the assumption that no peer has the
 -- piece and that every piece is pending download.
-mkPieceMap :: Integer -> ByteString -> Map Integer PieceData
+mkPieceMap :: Integer -> ByteString -> PieceMap
 mkPieceMap numPieces pieceHash = fromList kvs
   where kvs = [(i, PieceData { peers = []
                              , state = Pending
                              , hash = h }) | (i, h) <- zip [0..numPieces] hashes]
         hashes = splitN (fromIntegral numPieces) pieceHash
 
+havePiece :: PieceMap -> Integer -> Bool
+havePiece pm index =
+  state (pm ! index) == Have
+
 genHandShakeMsg :: ByteString -> String -> ByteString
 genHandShakeMsg infoHash peer_id = concat [pstrlen, pstr, reserved, infoHash, peerID]
   where pstrlen = singleton 19
@@ -161,6 +167,11 @@ getMsg h = do
     msg <- hGet h l
     return $ decode $ fromStrict $ concat [lBS, msg]
 
+sendMsg :: Handle -> PeerMsg -> IO ()
+sendMsg h msg =
+  let bsMsg = toStrict $ encode msg
+  in
+   hPut h bsMsg
 
 bsToInt :: ByteString -> Int
 bsToInt x = fromIntegral (runGet getWord32be (fromChunks (return x)))
@@ -169,36 +180,50 @@ bitfieldToList :: [Word8] -> [Integer]
 bitfieldToList bs = go bs 0
   where go [] _ = []
         go (b:bs') pos =
-          let setBits = [pos*8 + (toInteger i) | i <- [0..8], testBit b i]
+          let setBits = [pos*8 + toInteger i | i <- [0..8], testBit b i]
           in
-           setBits ++ (go bs' (pos + 1))
+           setBits ++ go bs' (pos + 1)
 
 -- downloadPiece :: Integer -> Handle -> IO ()
 
 createDummyFile :: FilePath -> Int -> IO ()
-createDummyFile path size = do
+createDummyFile path size =
   writeFile path (BC.replicate size '\0')
 
 -- loop1 :: shake hands with all peers, find out the pieces they have, form PieceData.
 -- recvMsg :: Peer -> Handle -> Msg
-msgLoop :: Handle -> ByteString -> IO ()
-msgLoop h pieceHash =
+msgLoop :: PeerState -> ByteString -> IO ()
+msgLoop state pieceHash =
   let numPieces = (toInteger . (`quot` 20) . BC.length) pieceHash
       pieceStatus = mkPieceMap numPieces pieceHash
   in
    forever $ do
-     msg <- getMsg h
+     -- if meInterested and he NOT Choking, pick a piece to download
+     -- and send a requestmsg.
+     msg <- getMsg (handle state)
      putStrLn $ "got a " ++ show msg
      case msg of
       BitFieldMsg bss -> do
         let pieceList = bitfieldToList (unpack bss)
-        putStrLn (show pieceList)
+        print pieceList
+        -- for each pieceIndex in pieceList, make an entry in the pieceStatus
+        -- map with pieceIndex as the key and modify the value to add the peer.
+
         -- download each of the piece in order
-      _ -> putStrLn (show msg)
+      UnChokeMsg -> do
+        print msg
+        msgLoop (state {heChoking = False}) pieceHash
+      _ -> print msg
 
 handlePeerMsgs :: Peer -> Metainfo -> String -> (String -> IO ()) -> IO ()
 handlePeerMsgs p m peerId logFn = do
   h <- handShake p (infoHash m) peerId
-  logFn $ "handShake"
-  msgLoop h (pieces (info m))
+  logFn "handShake"
+  let state = PeerState { handle = h
+                        , peer = p
+                        , heInterested = False
+                        , heChoking = True
+                        , meInterested = True
+                        , meChoking = False }
+  msgLoop state (pieces (info m))