Refactored piece manager.

src/BitTorrent/PieceManager.hs

@@ -14,14 +14,18 @@ import BitTorrent.Types
 runPieceMgr :: Metainfo -> Process ()
 runPieceMgr m = do
     let pieceCount = length $ mtPieces m
-        db = array (0, pieceCount - 1) [(x, []) | x <- [0..(pieceCount - 1)]]
-    mdb <- liftIO $ newMVar db
+    mdb <- liftIO $ newMVar $ initDb pieceCount
 
     dbUpdaterPid <- spawnLocal $ runDbUpdater mdb
     register "db_updater" dbUpdaterPid
 
+    -- Wait a bit for all Have messages to come in
     liftIO $ delaySeconds 3
 
+    fetchPieces pieceCount mdb
+
+fetchPieces :: Int -> MVar (Array Int [ProcessId]) -> Process ()
+fetchPieces pieceCount mdb = do
     -- Iterate linearly over all pieces
     forM_ [0..(pieceCount - 1)] $ \i -> do
         say $ "Downloading piece " ++ show i ++ "/" ++ show pieceCount
@@ -33,7 +37,7 @@ runPieceMgr m = do
 
         unless (null peers) $ do
           -- Tell the first peer in the list to download this piece
-          say $ "Sending to peer " ++ show (head peers)
+          say $ "Requesting peer " ++ show (head peers) ++ " download piece " ++ show i
           send (head peers) $ PeerFetch i
 
 runDbUpdater :: MVar (Array Int [ProcessId]) -> Process ()
@@ -42,6 +46,8 @@ runDbUpdater mdb = do
     liftIO $ modifyMVar_ mdb $ \v -> return $ updateDb v pid n
     runDbUpdater mdb
 
+initDb :: Int -> Array Int [ProcessId]
+initDb pc = array (0, pc - 1) [(x, []) | x <- [0..(pc - 1)]]
 
 updateDb :: Array Int [ProcessId] -> ProcessId -> Int -> Array Int [ProcessId]
 updateDb db pid n = db // [(n, pid : db ! n)]