refactoring to make Main simpler

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

diff --git a/src/FuncTorrent/Metainfo.hs b/src/FuncTorrent/Metainfo.hs
index a3313d18cbb5c6338de4a38466719af25ad47258..4eece7d5248a0ff257c1f9e02dd9d2e31b924a9e 100644 (file)
--- a/src/FuncTorrent/Metainfo.hs
+++ b/src/FuncTorrent/Metainfo.hs
@@ -46,7 +46,7 @@ mkInfo (Bdict m) = let (Bint pieceLength') = m ! "piece length"
                                 , md5sum = md5sum'}
 mkInfo _ = Nothing
 
-mkMetaInfo :: BVal   -> Maybe Metainfo
+mkMetaInfo :: BVal   -> Either String Metainfo
 mkMetaInfo (Bdict m)  =
     let (Just info')  = mkInfo $ m ! "info"
         announce'     = lookup "announce" m
@@ -55,18 +55,18 @@ mkMetaInfo (Bdict 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'
-           , infoHash     = hash . encode $ (m ! "info")
-        }
+    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 _ = Nothing
+mkMetaInfo _ = Left "mkMetaInfo: expect an input dict"
 
 getAnnounceList :: Maybe BVal -> [String]
 getAnnounceList Nothing = []