+ Add some utility functions.

1 files changed, 13 insertions, 0 deletions

diff --git a/src/Data/Torrent.hs b/src/Data/Torrent.hs
index 41b78922..e6ed8813 100644
--- a/src/Data/Torrent.hs
+++ b/src/Data/Torrent.hs
@@ -11,6 +11,7 @@
 module Data.Torrent
        ( module Data.Torrent.InfoHash
        , Torrent(..), ContentInfo(..), FileInfo(..)
+       , contenLength, pieceCount
        , fromFile
        ) where
 
@@ -216,6 +217,18 @@ instance BEncodable FileInfo where
 
   fromBEncode _ = decodingError "FileInfo"
 
+sizeInBase :: Integer -> Int -> Int
+sizeInBase n b = fromIntegral (n `div` fromIntegral b) + align
+  where
+    align = if n `mod` fromIntegral b == 0 then 0 else 1
+
+contentLength :: ContentInfo -> Integer
+contentLength SingleFile { ciLength = len } = len
+contentLength MultiFile  { ciFiles  = tfs } = sum (map fiLength tfs)
+
+pieceCount :: ContentInfo -> Int
+pieceCount ti = contentLength ti `sizeInBase` ciPieceLength ti
+
 
 -- | Read and decode a .torrent file.
 fromFile :: FilePath -> IO (Result Torrent)