{- git-annex output messages
 -
 - Copyright 2010-2016 Joey Hess <id@joeyh.name>
 -
 - Licensed under the GNU GPL version 3 or higher.
 -}

module Messages (
	showStart,
	ActionItem,
	mkActionItem,
	showStart',
	showNote,
	showAction,
	showSideAction,
	doSideAction,
	doQuietSideAction,
	showStoringStateAction,
	showOutput,
	showLongNote,
	showEndOk,
	showEndFail,
	showEndResult,
	endResult,
	toplevelWarning,
	warning,
	earlyWarning,
	warningIO,
	indent,
	JSON.JSONChunk(..),
	maybeShowJSON,
	showFullJSON,
	showCustom,
	showHeader,
	showRaw,
	setupConsole,
	enableDebugOutput,
	disableDebugOutput,
	debugEnabled,
	commandProgressDisabled,
	outputMessage,
	implicitMessage,
	withMessageState,
) where

import System.Log.Logger
import System.Log.Formatter
import System.Log.Handler (setFormatter)
import System.Log.Handler.Simple

import Common
import Types
import Types.Messages
import Types.ActionItem
import Messages.Internal
import qualified Messages.JSON as JSON
import qualified Annex

showStart :: String -> FilePath -> Annex ()
showStart command file = outputMessage json $
	command ++ " " ++ file ++ " "
  where
	json = JSON.start command (Just file) Nothing

showStart' :: String -> Key -> ActionItem -> Annex ()
showStart' command key i = outputMessage json $
	command ++ " " ++ actionItemDesc i key ++ " "
  where
	json = JSON.start command (actionItemWorkTreeFile i) (Just key)

showNote :: String -> Annex ()
showNote s = outputMessage (JSON.note s) $ "(" ++ s ++ ") "

showAction :: String -> Annex ()
showAction s = showNote $ s ++ "..."

showSideAction :: String -> Annex ()
showSideAction m = Annex.getState Annex.output >>= go
  where
	go st
		| sideActionBlock st == StartBlock = do
			p
			let st' = st { sideActionBlock = InBlock }
			Annex.changeState $ \s -> s { Annex.output = st' }
		| sideActionBlock st == InBlock = return ()
		| otherwise = p
	p = outputMessage JSON.none $ "(" ++ m ++ "...)\n"
			
showStoringStateAction :: Annex ()
showStoringStateAction = showSideAction "recording state in git"

{- Performs an action, supressing showSideAction messages. -}
doQuietSideAction :: Annex a -> Annex a
doQuietSideAction = doSideAction' InBlock

{- Performs an action, that may call showSideAction multiple times.
 - Only the first will be displayed. -}
doSideAction :: Annex a -> Annex a
doSideAction = doSideAction' StartBlock

doSideAction' :: SideActionBlock -> Annex a -> Annex a
doSideAction' b a = do
	o <- Annex.getState Annex.output
	set $ o { sideActionBlock = b }
	set o `after` a
  where
	set o = Annex.changeState $ \s -> s {  Annex.output = o }

{- Make way for subsequent output of a command. -}
showOutput :: Annex ()
showOutput = unlessM commandProgressDisabled $
	outputMessage JSON.none "\n"

showLongNote :: String -> Annex ()
showLongNote s = outputMessage (JSON.note s) ('\n' : indent s ++ "\n")

showEndOk :: Annex ()
showEndOk = showEndResult True

showEndFail :: Annex ()
showEndFail = showEndResult False

showEndResult :: Bool -> Annex ()
showEndResult ok = outputMessage (JSON.end ok) $ endResult ok ++ "\n"

endResult :: Bool -> String
endResult True = "ok"
endResult False = "failed"

toplevelWarning :: Bool -> String -> Annex ()
toplevelWarning makeway s = warning' makeway ("git-annex: " ++ s)

warning :: String -> Annex ()
warning = warning' True . indent

earlyWarning :: String -> Annex ()
earlyWarning = warning' False

warning' :: Bool -> String -> Annex ()
warning' makeway w = do
	when makeway $
		outputMessage JSON.none "\n"
	outputError (w ++ "\n")

{- Not concurrent output safe. -}
warningIO :: String -> IO ()
warningIO w = do
	putStr "\n"
	hFlush stdout
	hPutStrLn stderr w

indent :: String -> String
indent = intercalate "\n" . map (\l -> "  " ++ l) . lines

{- Shows a JSON chunk only when in json mode. -}
maybeShowJSON :: JSON.JSONChunk v -> Annex ()
maybeShowJSON v = void $ withMessageState $ outputJSON (JSON.add v)

{- Shows a complete JSON value, only when in json mode. -}
showFullJSON :: JSON.JSONChunk v -> Annex Bool
showFullJSON v = withMessageState $ outputJSON (JSON.complete v)

{- Performs an action that outputs nonstandard/customized output, and
 - in JSON mode wraps its output in JSON.start and JSON.end, so it's
 - a complete JSON document.
 - This is only needed when showStart and showEndOk is not used.
 -}
showCustom :: String -> Annex Bool -> Annex ()
showCustom command a = do
	outputMessage (JSON.start command Nothing Nothing) ""
	r <- a
	outputMessage (JSON.end r) ""

showHeader :: String -> Annex ()
showHeader h = outputMessage JSON.none $ (h ++ ": ")

showRaw :: String -> Annex ()
showRaw s = outputMessage JSON.none (s ++ "\n")

setupConsole :: IO ()
setupConsole = do
	s <- setFormatter
		<$> streamHandler stderr DEBUG
		<*> pure preciseLogFormatter
	updateGlobalLogger rootLoggerName (setLevel NOTICE . setHandlers [s])
	setConsoleEncoding
	{- Force output to be line buffered. This is normally the case when
	 - it's connected to a terminal, but may not be when redirected to
	 - a file or a pipe. -}
	hSetBuffering stdout LineBuffering
	hSetBuffering stderr LineBuffering

{- Log formatter with precision into fractions of a second. -}
preciseLogFormatter :: LogFormatter a
preciseLogFormatter = tfLogFormatter "%F %X%Q" "[$time] $msg"

enableDebugOutput :: IO ()
enableDebugOutput = updateGlobalLogger rootLoggerName $ setLevel DEBUG

disableDebugOutput :: IO ()
disableDebugOutput = updateGlobalLogger rootLoggerName $ setLevel NOTICE

{- Checks if debugging is enabled. -}
debugEnabled :: IO Bool
debugEnabled = do
	l <- getRootLogger
	return $ getLevel l <= Just DEBUG

{- Should commands that normally output progress messages have that
 - output disabled? -}
commandProgressDisabled :: Annex Bool
commandProgressDisabled = withMessageState $ \s -> return $
	case outputType s of
		QuietOutput -> True
		JSONOutput _ -> True
		NormalOutput -> concurrentOutputEnabled s

{- Use to show a message that is displayed implicitly, and so might be
 - disabled when running a certian command that needs more control over its
 - output. -}
implicitMessage :: Annex () -> Annex ()
implicitMessage = whenM (implicitMessages <$> Annex.getState Annex.output)