+{-
+ - Copyright (C) 2015-2016 Ramakrishnan Muthukrishnan <ram@rkrishnan.org>
+ -
+ - This file is part of FuncTorrent.
+ -
+ - FuncTorrent is free software; you can redistribute it and/or modify
+ - it under the terms of the GNU General Public License as published by
+ - the Free Software Foundation; either version 3 of the License, or
+ - (at your option) any later version.
+ -
+ - FuncTorrent is distributed in the hope that it will be useful,
+ - but WITHOUT ANY WARRANTY; without even the implied warranty of
+ - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ - GNU General Public License for more details.
+ -
+ - You should have received a copy of the GNU General Public License
+ - along with FuncTorrent; if not, see <http://www.gnu.org/licenses/>
+ -}
+
+{-# LANGUAGE OverloadedStrings #-}
module FuncTorrent.Metainfo
(Info(..),
Metainfo(..),
- infoHash,
- mkInfo,
- mkMetaInfo
+ torrentToMetainfo
) where
import Prelude hiding (lookup)
import Crypto.Hash.SHA1 (hash)
import Data.Maybe (maybeToList)
-import FuncTorrent.Bencode (BVal(..), InfoDict, encode, bstrToString, bValToInteger)
+import FuncTorrent.Bencode (BVal(..), encode, decode, bstrToString, bValToInteger)
-- only single file mode supported for the time being.
data Info = Info { pieceLength :: !Integer
, md5sum :: !(Maybe String)
} deriving (Eq, Show)
-data Metainfo = Metainfo { info :: !Info
+data Metainfo = Metainfo { info :: !(Maybe Info)
, announceList :: ![String]
, creationDate :: !(Maybe Integer)
, comment :: !(Maybe String)
, createdBy :: !(Maybe String)
, encoding :: !(Maybe String)
+ , infoHash :: !ByteString
} deriving (Eq, Show)
-mkInfo :: BVal -> Maybe Info
-mkInfo (Bdict m) = let (Bint pieceLength') = m ! "piece length"
- (Bstr pieces') = m ! "pieces"
- private' = Nothing
- (Bstr name') = m ! "name"
- (Bint length') = m ! "length"
- md5sum' = Nothing
- in Just Info { pieceLength = pieceLength'
- , pieces = pieces'
- , private = private'
- , name = unpack name'
- , lengthInBytes = length'
- , md5sum = md5sum'}
-mkInfo _ = Nothing
+bvalToInfo :: BVal -> Maybe Info
+bvalToInfo (Bdict m) = let (Bint pieceLength') = m ! "piece length"
+ (Bstr pieces') = m ! "pieces"
+ private' = Nothing
+ (Bstr name') = m ! "name"
+ (Bint length') = m ! "length"
+ md5sum' = Nothing
+ in Just Info { pieceLength = pieceLength'
+ , pieces = pieces'
+ , private = private'
+ , name = unpack name'
+ , lengthInBytes = length'
+ , md5sum = md5sum'}
+bvalToInfo _ = Nothing
-mkMetaInfo :: BVal -> Maybe Metainfo
+mkMetaInfo :: BVal -> Either String Metainfo
mkMetaInfo (Bdict m) =
- let (Just info') = mkInfo $ m ! "info"
+ let info' = bvalToInfo $ m ! "info"
announce' = lookup "announce" m
announceList' = lookup "announce-list" m
creationDate' = lookup "creation date" m
comment' = lookup "comment" m
createdBy' = lookup "created by" m
encoding' = lookup "encoding" m
- in Just Metainfo {
- info = info'
- , announceList = maybeToList (announce' >>= bstrToString)
- ++ getAnnounceList announceList'
- , creationDate = bValToInteger =<< creationDate'
- , comment = bstrToString =<< comment'
- , createdBy = bstrToString =<< createdBy'
- , encoding = bstrToString =<< encoding'
- }
-mkMetaInfo _ = Nothing
+ in Right Metainfo {
+ info = info'
+ , announceList = maybeToList (announce' >>= bstrToString)
+ ++ getAnnounceList announceList'
+ , creationDate = bValToInteger =<< creationDate'
+ , comment = bstrToString =<< comment'
+ , createdBy = bstrToString =<< createdBy'
+ , encoding = bstrToString =<< encoding'
+ , infoHash = hash . encode $ (m ! "info")
+ }
+mkMetaInfo _ = Left "mkMetaInfo: expect an input dict"
getAnnounceList :: Maybe BVal -> [String]
getAnnounceList Nothing = []
[Bstr s''] -> unpack s''
_ -> ""
_ -> "") l
-
getAnnounceList (Just (Bdict _)) = []
--- | Info hash is urlencoded 20 byte SHA1 hash of the value of the info key from
--- the Metainfo file. Note that the value will be a bencoded dictionary, given
--- the definition of the info key above. TODO: `Metainfo -> ByteString`
-infoHash :: InfoDict -> ByteString
-infoHash m = hash . encode $ (m ! "info")
+torrentToMetainfo :: ByteString -> Either String Metainfo
+torrentToMetainfo s =
+ case decode s of
+ Right d -> mkMetaInfo d
+ Left e -> Left $ show e