module Data.Torrent.Tree
(
DirTree (..)
, build
, Data.Torrent.Tree.lookup
, lookupDir
, fileNumber
, dirNumber
) where
import Data.ByteString as BS
import Data.ByteString.Char8 as BC
import Data.Foldable
import Data.List as L
import Data.Map as M
import Data.Monoid
import Data.Torrent.Layout
data DirTree a = Dir { children :: Map ByteString (DirTree a) }
| File { node :: FileInfo a }
deriving Show
build :: LayoutInfo -> DirTree ()
build SingleFile {liFile = FileInfo {..}} = Dir
{ children = M.singleton fiName (File fi) }
where
fi = FileInfo fiLength fiMD5Sum ()
build MultiFile {..} = Dir $ M.singleton liDirName files
where
files = Dir $ M.fromList $ L.map mkFileEntry liFiles
mkFileEntry FileInfo {..} = (L.head fiName, ent)
where
ent = File $ FileInfo fiLength fiMD5Sum ()
lookup :: [FilePath] -> DirTree a -> Maybe (DirTree a)
lookup [] t = Just t
lookup (p : ps) (Dir m) | Just subTree <- M.lookup (BC.pack p) m
= Data.Torrent.Tree.lookup ps subTree
lookup _ _ = Nothing
lookupDir :: [FilePath] -> DirTree a -> Maybe [(ByteString, DirTree a)]
lookupDir ps d = do
subTree <- Data.Torrent.Tree.lookup ps d
case subTree of
File _ -> Nothing
Dir es -> Just $ M.toList es
fileNumber :: DirTree a -> Sum Int
fileNumber File {..} = Sum 1
fileNumber Dir {..} = foldMap fileNumber children
dirNumber :: DirTree a -> Sum Int
dirNumber File {..} = Sum 0
dirNumber Dir {..} = Sum 1 <> foldMap dirNumber children