{- git-annex output messages
 -
 - Copyright 2010-2011 Joey Hess <joey@kitenet.net>
 -
 - Licensed under the GNU GPL version 3 or higher.
 -}

module Messages (
	showStart,
	showNote,
	showAction,
	showProgress,
	metered,
	meteredBytes,
	showSideAction,
	doSideAction,
	doQuietSideAction,
	showStoringStateAction,
	showOutput,
	showLongNote,
	showEndOk,
	showEndFail,
	showEndResult,
	showErr,
	warning,
	fileNotFound,
	indent,
	maybeShowJSON,
	showFullJSON,
	showCustom,
	showHeader,
	showRaw,
	
	setupConsole
) where

import Text.JSON
import Data.Progress.Meter
import Data.Progress.Tracker
import Data.Quantity
import System.Log.Logger
import System.Log.Formatter
import System.Log.Handler (setFormatter, LogHandler)
import System.Log.Handler.Simple

import Common
import Types
import Types.Messages
import Types.Key
import qualified Annex
import qualified Messages.JSON as JSON
import qualified Data.Set as S

showStart :: String -> String -> Annex ()
showStart command file = handle (JSON.start command $ Just file) $
	flushed $ putStr $ command ++ " " ++ file ++ " "

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

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

{- Progress dots. -}
showProgress :: Annex ()
showProgress = handle q $
	flushed $ putStr "."

{- Shows a progress meter while performing a transfer of a key.
 - The action is passed a callback to use to update the meter. -}
metered :: (Maybe MeterUpdate) -> Key -> (MeterUpdate -> Annex a) -> Annex a
metered combinemeterupdate key a = go (keySize key)
  where
	go (Just size) = meteredBytes combinemeterupdate size a
	go _ = a (const noop)

{- Shows a progress meter while performing an action on a given number
 - of bytes. -}
meteredBytes :: (Maybe MeterUpdate) -> Integer -> (MeterUpdate -> Annex a) -> Annex a
meteredBytes combinemeterupdate size a = withOutputType go
  where
	go NormalOutput = do
		progress <- liftIO $ newProgress "" size
		meter <- liftIO $ newMeter progress "B" 25 (renderNums binaryOpts 1)
		showOutput
		r <- a $ \n -> liftIO $ do
			incrP progress n
			displayMeter stdout meter
			maybe noop (\m -> m n) combinemeterupdate
		liftIO $ clearMeter stdout meter
		return r
	go _ = a (const noop)

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 = handle q $ putStrLn $ "(" ++ m ++ "...)"
			
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 }

showOutput :: Annex ()
showOutput = handle q $
	putStr "\n"

showLongNote :: String -> Annex ()
showLongNote s = handle (JSON.note s) $
	putStrLn $ '\n' : indent s

showEndOk :: Annex ()
showEndOk = showEndResult True

showEndFail :: Annex ()
showEndFail = showEndResult False

showEndResult :: Bool -> Annex ()
showEndResult ok = handle (JSON.end ok) $ putStrLn msg
  where
	msg
		| ok = "ok"
		| otherwise = "failed"

showErr :: (Show a) => a -> Annex ()
showErr e = warning' $ "git-annex: " ++ show e

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

warning' :: String -> Annex ()
warning' w = do
	handle q $ putStr "\n"
	liftIO $ do
		hFlush stdout
		hPutStrLn stderr w

{- Displays a warning one time about a file the user specified not existing. -}
fileNotFound :: FilePath -> Annex ()
fileNotFound file = do
	st <- Annex.getState Annex.output
	let shown = fileNotFoundShown st
	when (S.notMember file shown) $ do
		let shown' = S.insert file shown
		let st' = st { fileNotFoundShown = shown' }
		Annex.changeState $ \s -> s { Annex.output = st' }
		liftIO $ hPutStrLn stderr $ unwords
			[ "git-annex:", file, "not found" ]

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

{- Shows a JSON fragment only when in json mode. -}
maybeShowJSON :: JSON a => [(String, a)] -> Annex ()
maybeShowJSON v = handle (JSON.add v) q

{- Shows a complete JSON value, only when in json mode. -}
showFullJSON :: JSON a => [(String, a)] -> Annex Bool
showFullJSON v = withOutputType $ liftIO . go
  where
	go JSONOutput = JSON.complete v >> return True
	go _ = return False

{- 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
	handle (JSON.start command Nothing) q
	r <- a
	handle (JSON.end r) q

showHeader :: String -> Annex ()
showHeader h = handle q $
	flushed $ putStr $ h ++ ": "

showRaw :: String -> Annex ()
showRaw s = handle q $ putStrLn s

setupConsole :: IO ()
setupConsole = do
	s <- setFormatter
		<$> streamHandler stderr DEBUG
		<*> pure (simpleLogFormatter "[$time] $msg")
	updateGlobalLogger rootLoggerName (setLevel NOTICE . setHandlers [s])
	{- This avoids ghc's output layer crashing on
	 - invalid encoded characters in
	 - filenames when printing them out. -}
	fileEncoding stdout
	fileEncoding stderr

handle :: IO () -> IO () -> Annex ()
handle json normal = withOutputType go
  where
	go NormalOutput = liftIO normal
	go QuietOutput = q
	go JSONOutput = liftIO $ flushed json

q :: Monad m => m ()
q = noop

flushed :: IO () -> IO ()
flushed a = a >> hFlush stdout

withOutputType :: (OutputType -> Annex a) -> Annex a
withOutputType a = outputType <$> Annex.getState Annex.output >>= a