{- git-annex command
 -
 - Copyright 2012 Joey Hess <id@joeyh.name>
 -
 - Licensed under the GNU GPL version 3 or higher.
 -}

module Command.Indirect where

import Common.Annex
import Command
import qualified Git
import qualified Git.Branch
import qualified Git.LsFiles
import Git.FileMode
import Config
import qualified Annex
import Annex.Direct
import Annex.Content
import Annex.Content.Direct
import Annex.CatFile
import Annex.Init
import qualified Command.Add

cmd :: Command
cmd = notBareRepo $ noDaemonRunning $
	command "indirect" paramNothing seek
		SectionSetup "switch repository to indirect mode"

seek :: CommandSeek
seek = withNothing start

start :: CommandStart
start = ifM isDirect
	( do
		unlessM (coreSymlinks <$> Annex.getGitConfig) $
			error "Git is configured to not use symlinks, so you must use direct mode."
		whenM probeCrippledFileSystem $
			error "This repository seems to be on a crippled filesystem, you must use direct mode."
		next perform
	, stop
	)

perform :: CommandPerform
perform = do
	showStart "commit" ""
	whenM stageDirect $ do
		showOutput
		void $ inRepo $ Git.Branch.commitCommand Git.Branch.ManualCommit
			[ Param "-m"
			, Param "commit before switching to indirect mode"
			]
	showEndOk

	-- Note that we set indirect mode early, so that we can use
	-- moveAnnex in indirect mode.
	setDirect False

	top <- fromRepo Git.repoPath
	(l, clean) <- inRepo $ Git.LsFiles.stagedOthersDetails [top]
	forM_ l go
	void $ liftIO clean
	next cleanup
  where
	{- Walk tree from top and move all present direct mode files into
	 - the annex, replacing with symlinks. Also delete direct mode
	 - caches and mappings. -}
	go (f, Just sha, Just mode) | isSymLink mode = do
		r <- liftIO $ catchMaybeIO $ getSymbolicLinkStatus f
		case r of
			Just s
				| isSymbolicLink s -> void $ flip whenAnnexed f $
					\_ k -> do
						removeInodeCache k
						removeAssociatedFiles k
						return Nothing
				| otherwise -> 
					maybe noop (fromdirect f)
						=<< catKey sha mode
			_ -> noop
	go _ = noop

	fromdirect f k = do
		showStart "indirect" f
		removeInodeCache k
		removeAssociatedFiles k
		whenM (liftIO $ not . isSymbolicLink <$> getSymbolicLinkStatus f) $ do
			v <- tryNonAsync (moveAnnex k f)
			case v of
				Right _ -> do 
					l <- calcRepo $ gitAnnexLink f k
					liftIO $ createSymbolicLink l f
				Left e -> catchNonAsync (Command.Add.undo f k e)
					warnlocked
		showEndOk

	warnlocked :: SomeException -> Annex ()
	warnlocked e = do
		warning $ show e
		warning "leaving this file as-is; correct this problem and run git annex add on it"
	
cleanup :: CommandCleanup
cleanup = do
	showStart "indirect" ""
	showEndOk
	return True