module Craft.File
( module Craft.File
, setGroupID
, setOwnerID
, getOwnerID
, getGroupID
, getMode
)
where

import           Control.Lens
import           Data.ByteString (ByteString)
import           Data.Maybe
import           Formatting

import qualified Craft.Group     as Group
import           Craft.Internal
import qualified Craft.User      as User


getOwner :: File -> Craft User
getOwner f =
  User.fromID (f ^. ownerID) >>= \case
    Nothing -> $craftError $ formatToString ("No such owner with `"%shown%"` for: "%shown)
                                            (f ^. ownerID) f
    Just g  -> return g


getGroup :: File -> Craft Group
getGroup f =
  Group.fromID (f ^. groupID) >>= \case
    Nothing -> $craftError $ formatToString ("No such group with `"%shown%"` for: "%shown)
                                            (f ^. groupID) f
    Just g -> return g


-- TODO: name :: Lens' File (Path Rel FileP)
name :: Getter File (Path Rel FileP)
name = filePath . to filename


multiple :: [Path Abs FileP] -> Mode -> User -> Group -> Maybe ByteString -> [File]
multiple paths mode' owner' group' content' = map go paths
 where
  go path' = File path' mode' (owner'^.uid) (group'^.gid) content'


setStats :: File -> Craft ()
setStats f = do
  let fp = f^.path
  setMode    (f^.mode)    fp
  setOwnerID (f^.ownerID) fp
  setGroupID (f^.groupID) fp


write :: Path Abs FileP -> ByteString -> Craft ()
write = fileWrite


exists :: Path Abs FileP -> Craft Bool
exists fp = isExecSucc <$> exec "test" ["-f", fromAbsFile fp]


get :: Path Abs FileP -> Craft (Maybe File)
get fp =
  getStats fp >>= \case
    Nothing -> return Nothing
    Just (m, o, g) -> do
      return . Just $ file fp & mode    .~ m
                              & ownerID .~ o
                              & groupID .~ g
                              & fileContent .~ Nothing


getWithContent :: Path Abs FileP -> Craft (Maybe File)
getWithContent fp =
  get fp >>= \case
    Nothing -> return Nothing
    Just f  -> do
      content' <- fileRead fp
      return . Just $ f & fileContent ?~ content'


md5sum :: Path Abs FileP -> Craft String
md5sum fp = head . words <$> ($stdoutOrError =<< exec "md5sum" [fromAbsFile fp])


-- | A thin wrapper over the Unix find program.
find :: Path Abs Dir -> Args -> Craft [File]
find dir args = do
  fs <- mapM parseAbsFile . lines =<< $stdoutOrError =<< exec "find" ([fromAbsDir dir, "-type", "f"] ++ args)
  catMaybes <$> (mapM get fs)