full autostart support

git annex assistant --autostart will start separate daemons in each
listed autostart repo

running the webapp outside any git-annex repo will open it on the
first listed autostart repo

Command/Assistant.hs

@@ -7,12 +7,66 @@
 
 module Command.Assistant where
 
+import Common.Annex
 import Command
+import qualified Option
 import qualified Command.Watch
+import Init
+import Locations.UserConfig
+
+import System.Environment
+import System.Posix.Directory
 
 def :: [Command]
-def = [withOptions [Command.Watch.foregroundOption, Command.Watch.stopOption] $ 
+def = [noRepo checkAutoStart $ dontCheck repoExists $
+	withOptions [Command.Watch.foregroundOption, Command.Watch.stopOption, autoStartOption] $ 
 	command "assistant" paramNothing seek "automatically handle changes"]
 
+autoStartOption :: Option
+autoStartOption = Option.flag [] "autostart" "start in known repositories"
+
 seek :: [CommandSeek]
-seek = Command.Watch.mkSeek True
+seek = [withFlag Command.Watch.stopOption $ \stopdaemon ->
+	withFlag Command.Watch.foregroundOption $ \foreground ->
+	withFlag autoStartOption $ \autostart ->
+	withNothing $ start foreground stopdaemon autostart]
+
+start :: Bool -> Bool -> Bool -> CommandStart
+start foreground stopdaemon autostart
+	| autostart = do
+		liftIO $ autoStart
+		stop
+	| otherwise = do
+		ensureInitialized
+		Command.Watch.start True foreground stopdaemon
+
+{- Run outside a git repository. Check to see if any parameter is
+ - --autostart and enter autostart mode. -}
+checkAutoStart :: IO ()
+checkAutoStart = ifM (any (== "--autostart") <$> getArgs)
+	( autoStart
+	, error "Not in a git repository."
+	) 
+
+autoStart :: IO ()
+autoStart = do
+	autostartfile <- autoStartFile
+	let nothing = error $ "Nothing listed in " ++ autostartfile
+	ifM (doesFileExist autostartfile)
+		( do
+			dirs <- lines <$> readFile autostartfile
+			programfile <- programFile
+			program <- catchDefaultIO (readFile programfile) "git-annex"
+			when (null dirs) nothing
+			forM_ dirs $ \d -> do
+				putStrLn $ "git-annex autostart in " ++ d
+				ifM (catchBoolIO $ go program d)
+					( putStrLn "ok"
+					, putStrLn "failed"
+					)
+		, nothing
+		)
+	where
+		go program dir = do
+			changeWorkingDirectory dir
+			boolSystem program [Param "assistant"]