{- git-annex
 -}

module Annex where

import Backend
import System.Posix.Files
import System.Directory
import GitRepo
import Utility

{- An annexed file's content is stored somewhere under .git/annex/ -}
annexLoc repo key = do
	dir <- gitDir repo
	return $ dir ++ "/annex/" ++ key

{- Annexes a file, storing it in a backend, and then moving it into
 - the annex directory and setting up the symlink pointing to its content. -}
annexFile :: [Backend] -> GitRepo -> FilePath -> IO ()
annexFile backends repo file = do
	alreadyannexed <- lookupBackend backends repo file
	case (alreadyannexed) of
		Just _ -> error $ "already annexed " ++ file
		Nothing -> do
			stored <- storeFile backends repo file
			case (stored) of
				Nothing -> error $ "no backend could store " ++ file
				Just key -> symlink key
	where
		symlink key = do
			dest <- annexLoc repo key
			createDirectoryIfMissing True (parentDir dest)
			renameFile file dest
			createSymbolicLink dest file
			gitAdd repo file