{- git-annex command
 -
 - Copyright 2012-2013 Joey Hess <id@joeyh.name>
 -
 - Licensed under the GNU GPL version 3 or higher.
 -}

module Command.Import where

import Common.Annex
import Command
import qualified Annex
import qualified Command.Add
import Utility.CopyFile
import Backend
import Remote
import Types.KeySource

cmd :: [Command]
cmd = [withOptions opts $ notBareRepo $ command "import" paramPaths seek
	SectionCommon "move and add files from outside git working copy"]

opts :: [Option]
opts = duplicateModeOptions ++ fileMatchingOptions

data DuplicateMode = Default | Duplicate | DeDuplicate | CleanDuplicates | SkipDuplicates
	deriving (Eq, Enum, Bounded)

associatedOption :: DuplicateMode -> Maybe Option
associatedOption Default = Nothing
associatedOption Duplicate = Just $
	flagOption [] "duplicate" "do not delete source files"
associatedOption DeDuplicate = Just $
	flagOption [] "deduplicate" "delete source files whose content was imported before"
associatedOption CleanDuplicates = Just $
	flagOption [] "clean-duplicates" "delete duplicate source files (import nothing)"
associatedOption SkipDuplicates = Just $
	flagOption [] "skip-duplicates" "import only new files"

duplicateModeOptions :: [Option]
duplicateModeOptions = mapMaybe associatedOption [minBound..maxBound]

getDuplicateMode :: Annex DuplicateMode
getDuplicateMode = go . catMaybes <$> mapM getflag [minBound..maxBound]
  where
	getflag m = case associatedOption m of
		Nothing -> return Nothing
		Just o -> ifM (Annex.getFlag (optionName o))
			( return (Just m)
			, return Nothing
			)
	go [] = Default
	go [m] = m
	go ms = error $ "cannot combine " ++
		unwords (map (optionParam . fromJust . associatedOption) ms)

seek :: CommandSeek
seek ps = do
	mode <- getDuplicateMode
	withPathContents (start mode) ps

start :: DuplicateMode -> (FilePath, FilePath) -> CommandStart
start mode (srcfile, destfile) =
	ifM (liftIO $ isRegularFile <$> getSymbolicLinkStatus srcfile)
		( do
			ma <- pickaction
			case ma of
				Nothing -> stop
				Just a -> do
					showStart "import" destfile
					next a
		, stop
		)
  where
	deletedup = do
		showNote "duplicate"
		liftIO $ removeFile srcfile
		next $ return True
	importfile = do
		handleexisting =<< liftIO (catchMaybeIO $ getSymbolicLinkStatus destfile)
		liftIO $ createDirectoryIfMissing True (parentDir destfile)
		liftIO $ if mode == Duplicate || mode == SkipDuplicates
			then void $ copyFileExternal CopyAllMetaData srcfile destfile
			else moveFile srcfile destfile
		Command.Add.perform destfile
	handleexisting Nothing = noop
	handleexisting (Just s)
		| isDirectory s = notoverwriting "(is a directory)"
		| otherwise = ifM (Annex.getState Annex.force)
			( liftIO $ nukeFile destfile
			, notoverwriting "(use --force to override)"
			)
	notoverwriting why = error $ "not overwriting existing " ++ destfile ++ " " ++ why
	checkdup dupa notdupa = do
		backend <- chooseBackend destfile
		let ks = KeySource srcfile srcfile Nothing
		v <- genKey ks backend
		isdup <- case v of
			Just (k, _) -> not . null <$> keyLocations k
			_ -> return False
		return $ if isdup then dupa else notdupa
	pickaction = case mode of
		DeDuplicate -> checkdup (Just deletedup) (Just importfile)
		CleanDuplicates -> checkdup (Just deletedup) Nothing
		SkipDuplicates -> checkdup Nothing (Just importfile)
		_ -> return (Just importfile)