{- git-annex output messages
 -
 - Copyright 2010-2019 Joey Hess <id@joeyh.name>
 -
 - Licensed under the GNU AGPL version 3 or higher.
 -}

{-# LANGUAGE OverloadedStrings #-}

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

import System.Log.Logger
import System.Log.Formatter
import System.Log.Handler (setFormatter)
import System.Log.Handler.Simple
import Control.Concurrent
import qualified Data.ByteString as S

import Common
import Types
import Types.Messages
import Types.ActionItem
import Types.Concurrency
import Types.Command (StartMessage(..))
import Types.Transfer (transferKey)
import Messages.Internal
import Messages.Concurrent
import qualified Messages.JSON as JSON
import qualified Annex

showStart :: String -> RawFilePath -> Annex ()
showStart command file = outputMessage json $
	encodeBS' command <> " " <> file <> " "
  where
	json = JSON.start command (Just file) Nothing

showStart' :: String -> Maybe String -> Annex ()
showStart' command mdesc = outputMessage json $ encodeBS' $
	command ++ (maybe "" (" " ++) mdesc) ++ " "
  where
	json = JSON.start command Nothing Nothing

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

showStartMessage :: StartMessage -> Annex ()
showStartMessage (StartMessage command ai) = case ai of
	ActionItemAssociatedFile _ k -> showStartKey command k ai
	ActionItemKey k -> showStartKey command k ai
	ActionItemBranchFilePath _ k -> showStartKey command k ai
	ActionItemFailedTransfer t _ -> showStartKey command (transferKey t) ai
	ActionItemWorkTreeFile file -> showStart command file
	ActionItemOther msg -> showStart' command msg
	OnlyActionOn _ ai' -> showStartMessage (StartMessage command ai')
showStartMessage (StartUsualMessages command ai) = do
	outputType <$> Annex.getState Annex.output >>= \case
		QuietOutput -> Annex.setOutput NormalOutput
		_ -> noop
	showStartMessage (StartMessage command ai)
showStartMessage (StartNoMessage _) = noop
showStartMessage (CustomOutput _) =
	outputType <$> Annex.getState Annex.output >>= \case
		NormalOutput -> Annex.setOutput QuietOutput
		_ -> noop

-- Only show end result if the StartMessage is one that gets displayed.
showEndMessage :: StartMessage -> Bool -> Annex ()
showEndMessage (StartMessage _ _) = showEndResult
showEndMessage (StartUsualMessages _ _) = showEndResult
showEndMessage (StartNoMessage _) = const noop
showEndMessage (CustomOutput _) = const noop

showNote :: String -> Annex ()
showNote s = outputMessage (JSON.note s) $ encodeBS' $ "(" ++ 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 $ encodeBS' $ "(" ++ 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 = bracket setup cleanup . const
  where
	setup = do
		o <- Annex.getState Annex.output
		set $ o { sideActionBlock = b }
		return o
	cleanup = set
	set o = Annex.changeState $ \s -> s { Annex.output = o }

{- Performs an action, suppressing all normal standard output,
 - but not json output. -}
doQuietAction :: Annex a -> Annex a
doQuietAction = bracket setup cleanup . const
  where
	setup = do
		o <- Annex.getState Annex.output
		case outputType o of
			NormalOutput -> set $ o { outputType = QuietOutput }
			_ -> noop
		return o
	cleanup = set
	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) (encodeBS' (formatLongNote s))

formatLongNote :: String -> String
formatLongNote s = '\n' : indent s ++ "\n"

-- Used by external special remote, displayed same as showLongNote
-- to console, but json object containing the info is emitted immediately.
showInfo :: String -> Annex ()
showInfo s = outputMessage' outputJSON (JSON.info s) $
	encodeBS' (formatLongNote s)

showEndOk :: Annex ()
showEndOk = showEndResult True

showEndFail :: Annex ()
showEndFail = showEndResult False

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

endResult :: Bool -> S.ByteString
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 $ bufferJSON (JSON.add v)

{- Shows a complete JSON value, only when in json mode. -}
showFullJSON :: JSON.JSONChunk v -> Annex Bool
showFullJSON v = withMessageState $ bufferJSON (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 :: S.ByteString -> Annex ()
showHeader h = outputMessage JSON.none (h <> ": ")

showRaw :: S.ByteString -> 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])
	{- 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

{- Prevents any concurrent console access while running an action, so
 - that the action is the only thing using the console, and can eg prompt
 - the user.
 -}
prompt :: Annex a -> Annex a
prompt a = debugLocks $ Annex.getState Annex.concurrency >>= \case
	NonConcurrent -> a
	(Concurrent _) -> goconcurrent
	ConcurrentPerCpu -> goconcurrent
  where
	goconcurrent = withMessageState $ \s -> do
		let l = promptLock s
		bracketIO
			(takeMVar l)
			(putMVar l)
			(const $ hideRegionsWhile s a)