+ Add very basic storage operations.

Now we can download and make some progress, but very unstable.

2 files changed, 24 insertions, 14 deletions

diff --git a/src/Data/Bitfield.hs b/src/Data/Bitfield.hs
index 46e0a71f..89461fd2 100644
--- a/src/Data/Bitfield.hs
+++ b/src/Data/Bitfield.hs
@@ -32,6 +32,7 @@ module Data.Bitfield
 
          -- * Construction
        , haveAll, haveNone, have, singleton
+       , interval
        , adjustSize
 
          -- * Query
@@ -137,6 +138,10 @@ singleton ix pc = have ix (haveNone pc)
 adjustSize :: PieceCount -> Bitfield -> Bitfield
 adjustSize s Bitfield {..} = Bitfield s bfSet
 
+-- | NOTE: for internal use only
+interval :: PieceCount -> PieceIx -> PieceIx -> Bitfield
+interval pc a b = Bitfield pc (S.interval a b)
+
 {-----------------------------------------------------------------------
     Query
 -----------------------------------------------------------------------}
@@ -174,16 +179,14 @@ notMember ix bf @ Bitfield {..}
   |     otherwise   = True
 
 -- | Find first available piece index.
-findMin :: Bitfield -> Maybe PieceIx
-findMin Bitfield {..}
-  | S.null bfSet = Nothing
-  |   otherwise  = Just (S.findMin bfSet)
+findMin :: Bitfield -> PieceIx
+findMin = S.findMin . bfSet
+{-# INLINE findMin #-}
 
 -- | Find last available piece index.
-findMax :: Bitfield -> Maybe PieceIx
-findMax Bitfield {..}
-  | S.null bfSet = Nothing
-  |   otherwise  = Just (S.findMax bfSet)
+findMax :: Bitfield -> PieceIx
+findMax = S.findMax . bfSet
+{-# INLINE findMax #-}
 
 isSubsetOf :: Bitfield -> Bitfield -> Bool
 isSubsetOf a b = bfSet a `S.isSubsetOf` bfSet b
@@ -333,11 +336,11 @@ strategyClass threshold = classify . completeness
 
 -- | Select the first available piece.
 strictFirst :: Selector
-strictFirst h a _ = findMin (difference a h)
+strictFirst h a _ = Just $ findMin (difference a h)
 
 -- | Select the last available piece.
 strictLast :: Selector
-strictLast h a _ = findMax (difference a h)
+strictLast h a _ = Just $ findMax (difference a h)
 
 -- |
 rarestFirst :: Selector
diff --git a/src/Data/Torrent.hs b/src/Data/Torrent.hs
index 551a260c..bdd38630 100644
--- a/src/Data/Torrent.hs
+++ b/src/Data/Torrent.hs
@@ -34,6 +34,8 @@ module Data.Torrent
        , contentLength, pieceCount, blockCount
        , isSingleFile, isMultiFile
 
+       , checkPiece
+
          -- * Info hash
 #if defined (TESTING)
        , InfoHash(..)
@@ -77,6 +79,9 @@ import Network.URI
 import System.FilePath
 import Numeric
 
+import Data.ByteString.Internal
+import Debug.Trace
+
 
 type Time = Text
 
@@ -141,6 +146,8 @@ simpleTorrent announce info = torrent announce info
                               Nothing Nothing Nothing
                               Nothing Nothing
 
+-- TODO check if pieceLength is power of 2
+
 -- | Info part of the .torrent file contain info about each content file.
 data ContentInfo =
     SingleFile {
@@ -361,14 +368,14 @@ slice from to = B.take to . B.drop from
 
 -- | Extract validation hash by specified piece index.
 pieceHash :: ContentInfo -> Int -> ByteString
-pieceHash ci ix = slice offset size (ciPieces ci)
+pieceHash ci ix = slice (hashsize * ix) hashsize (ciPieces ci)
   where
-    offset = ciPieceLength ci * ix
-    size   = ciPieceLength ci
+    hashsize   = 20
 
 -- | Validate piece with metainfo hash.
 checkPiece :: ContentInfo -> Int -> ByteString -> Bool
-checkPiece ci ix piece
+checkPiece ci ix piece @ (PS _ off si)
+  | traceShow (ix, off, si) True
   =  B.length piece == ciPieceLength ci
   && hash piece     == InfoHash (pieceHash ci ix)