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

module Command.Init where

import Control.Monad.State (liftIO)
import Control.Monad (when)
import System.Directory

import Command
import qualified Annex
import qualified GitRepo as Git
import UUID
import Version
import Messages
import Locations

seek :: [SubCmdSeek]
seek = [withString start]

{- Stores description for the repository etc. -}
start :: SubCmdStartString
start description = do
	when (null description) $
		error "please specify a description of this repository\n"
	showStart "init" description
	return $ Just $ perform description

perform :: String -> SubCmdPerform
perform description = do
	g <- Annex.gitRepo
	u <- getUUID g
	describeUUID u description
	setVersion
	liftIO $ gitAttributes g
	liftIO $ gitPreCommitHook g
	return $ Just cleanup

cleanup :: SubCmdCleanup
cleanup = do
	g <- Annex.gitRepo
	logfile <- uuidLog
	liftIO $ Git.run g ["add", logfile]
	liftIO $ Git.run g ["commit", "-m", "git annex init", logfile]
	return True

{- 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
			when (all (/= attrLine) (lines content)) $ do
				appendFile attributes $ attrLine ++ "\n"
				commit
	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]

{- set up a git pre-commit hook, if one is not already present -}
gitPreCommitHook :: Git.Repo -> IO ()
gitPreCommitHook repo = do
	let hook = Git.workTree repo ++ "/" ++ Git.gitDir repo ++
		"/hooks/pre-commit"
	exists <- doesFileExist hook
	if exists
		then putStrLn $ "pre-commit hook (" ++ hook ++ ") already exists, not configuring"
		else do
			writeFile hook $ "#!/bin/sh\n" ++
				"# automatically configured by git-annex\n" ++ 
				"git annex pre-commit .\n"
			p <- getPermissions hook
			setPermissions hook $ p {executable = True}