Peer: function to calculate the total bytes downloaded so far

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

diff --git a/src/FuncTorrent/Peer.hs b/src/FuncTorrent/Peer.hs
index 5e23fa112574c0ca07f6ddfbde0f36212a932720..9ca40f41efb7d4f774b0b53dc24caa6bd1bb7b79 100644 (file)
--- a/src/FuncTorrent/Peer.hs
+++ b/src/FuncTorrent/Peer.hs
@@ -4,7 +4,7 @@ module FuncTorrent.Peer
      handlePeerMsgs
     ) where
 
-import Prelude hiding (lookup, concat, replicate, splitAt, take)
+import Prelude hiding (lookup, concat, replicate, splitAt, take, filter)
 
 import System.IO (Handle, BufferMode(..), hSetBuffering)
 import Data.ByteString (ByteString, unpack, concat, hGet, hPut, take, empty)
@@ -13,8 +13,9 @@ import Network (connectTo, PortID(..))
 import Control.Monad.State
 import Data.Bits
 import Data.Word (Word8)
-import Data.Map (Map, fromList, toList, (!), mapWithKey, adjust)
+import Data.Map (Map, fromList, toList, (!), mapWithKey, adjust, filter)
 import qualified Crypto.Hash.SHA1 as SHA1 (hash)
+import Safe (headMay)
 
 import FuncTorrent.Metainfo (Info(..), Metainfo(..))
 import FuncTorrent.Utils (splitN, splitNum)
@@ -35,7 +36,7 @@ data PieceDlState = Pending
                   | Have
                   deriving (Show, Eq)
 
--- todo - map with index to a new data structure (peers who have that piece amd state)
+-- todo - map with index to a new data structure (peers who have that piece and state)
 data PieceData = PieceData { peers :: [Peer]        -- ^ list of peers who have this piece
                            , dlstate :: PieceDlState  -- ^ state of the piece from download perspective.
                            , hash  :: ByteString    -- ^ piece hash
@@ -102,13 +103,12 @@ toPeerState h p meCh meIn heCh heIn =
 -- simple algorithm to pick piece.
 -- pick the first piece from 0 that is not downloaded yet.
 pickPiece :: PieceMap -> Maybe Integer
-pickPiece m =
-  let pieceList = toList m
-      allPending = filter (\(_, v) -> dlstate v == Pending) pieceList
-  in
-   case allPending of
-    [] -> Nothing
-    ((i, _):_) -> Just i
+pickPiece =
+  (fst `liftM`) . headMay . toList . filter (\v -> dlstate v == Pending)
+
+bytesDownloaded :: PieceMap -> Integer
+bytesDownloaded =
+  sum . (map (len . snd)) . toList . filter (\v -> dlstate v == Have)
 
 updatePieceAvailability :: PieceMap -> Peer -> [Integer] -> PieceMap
 updatePieceAvailability pieceStatus p pieceList =