{- git-annex core functions -}

module Core where

import Maybe
import System.IO
import System.Directory
import Control.Monad.State (liftIO)
import System.Path
import Data.String.Utils

import Types
import Locations
import LocationLog
import UUID
import qualified GitRepo as Git
import qualified Annex
import Utility
			
{- Sets up a git repo for git-annex. -}
startup :: [Flag] -> Annex ()
startup flags = do
	mapM (\f -> Annex.flagChange f True) flags
	g <- Annex.gitRepo
	liftIO $ gitAttributes g
	prepUUID

{- When git-annex is done, it runs this. -}
shutdown :: Annex ()
shutdown = do
	g <- Annex.gitRepo

	liftIO $ Git.run g ["add", gitStateDir g]

	-- clean up any files left in the temp directory
	let tmp = annexTmpLocation g
	exists <- liftIO $ doesDirectoryExist tmp
	if (exists)
		then liftIO $ removeDirectoryRecursive $ tmp
		else return ()

{- configure git to use union merge driver on state files, if it is not
 - already -}
gitAttributes :: Git.Repo -> IO ()
gitAttributes repo = do
	exists <- doesFileExist attributes
	if (not exists)
		then do
			writeFile attributes $ attrLine ++ "\n"
			commit
		else do
			content <- readFile attributes
			if (all (/= attrLine) (lines content))
				then do
					appendFile attributes $ attrLine ++ "\n"
					commit
				else return ()
	where
		attrLine = stateLoc ++ "*.log merge=union"
		attributes = Git.attributes repo
		commit = do
			Git.run repo ["add", attributes]
			Git.run repo ["commit", "-m", "git-annex setup", 
					attributes]

{- Checks if a given key is currently present in the annexLocation -}
inAnnex :: Key -> Annex Bool
inAnnex key = do
	g <- Annex.gitRepo
	liftIO $ doesFileExist $ annexLocation g key

{- Calculates the relative path to use to link a file to a key. -}
calcGitLink :: FilePath -> Key -> Annex FilePath
calcGitLink file key = do
	g <- Annex.gitRepo
	cwd <- liftIO $ getCurrentDirectory
	let absfile = case (absNormPath cwd file) of
		Just f -> f
		Nothing -> error $ "unable to normalize " ++ file
	return $ (relPathDirToDir (parentDir absfile) (Git.workTree g)) ++
		annexLocationRelative g key

{- Updates the LocationLog when a key's presence changes. -}
logStatus :: Key -> LogStatus -> Annex ()
logStatus key status = do
	g <- Annex.gitRepo
	u <- getUUID g
	liftIO $ logChange g key u status

{- Output logging -}
showStart :: String -> String -> Annex ()
showStart command file = do
	liftIO $ putStr $ command ++ " " ++ file
	liftIO $ hFlush stdout
showNote :: String -> Annex ()
showNote s = do
	liftIO $ putStr $ " (" ++ s ++ ")"
	liftIO $ hFlush stdout
showLongNote :: String -> Annex ()
showLongNote s = do
	liftIO $ putStr $ "\n" ++ (indent s)
	where
		indent s = join "\n" $ map (\l -> "  " ++ l) $ lines s 
showEndOk :: Annex ()
showEndOk = do
	liftIO $ putStrLn " ok"
showEndFail :: String -> String -> Annex ()
showEndFail command file = do
	liftIO $ putStrLn ""
	liftIO $ hPutStrLn stderr $ command ++ " " ++ file ++ " failed"