{- git-annex v0 -> v1 upgrade support
 -
 - Copyright 2010 Joey Hess <joey@kitenet.net>
 -
 - Licensed under the GNU GPL version 3 or higher.
 -}

module Upgrade.V0 where

import System.IO.Error (try)

import Common.Annex
import Annex.Content
import qualified Upgrade.V1

upgrade :: Annex Bool
upgrade = do
	showAction "v0 to v1"

	-- do the reorganisation of the key files
	olddir <- fromRepo gitAnnexDir
	keys <- getKeysPresent0 olddir
	forM_ keys $ \k -> moveAnnex k $ olddir </> keyFile0 k

	-- update the symlinks to the key files
	-- No longer needed here; V1.upgrade does the same thing

	-- Few people had v0 repos, so go the long way around from 0 -> 1 -> 2
	Upgrade.V1.upgrade

-- these stayed unchanged between v0 and v1
keyFile0 :: Key -> FilePath
keyFile0 = Upgrade.V1.keyFile1
fileKey0 :: FilePath -> Key
fileKey0 = Upgrade.V1.fileKey1
lookupFile0 :: FilePath -> Annex (Maybe (Key, Backend Annex))
lookupFile0 = Upgrade.V1.lookupFile1

getKeysPresent0 :: FilePath -> Annex [Key]
getKeysPresent0 dir = do
	exists <- liftIO $ doesDirectoryExist dir
	if not exists
		then return []
		else do
			contents <- liftIO $ getDirectoryContents dir
			files <- liftIO $ filterM present contents
			return $ map fileKey0 files
	where
		present d = do
			result <- try $
				getFileStatus $ dir ++ "/" ++ takeFileName d
			case result of
				Right s -> return $ isRegularFile s
				Left _ -> return False