{-# LANGUAGE GeneralizedNewtypeDeriving #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE RecordWildCards #-}
module Patat.Main
( main
) where
import Control.Applicative ((<$>), (<*>))
import Control.Concurrent (forkIO, killThread, threadDelay)
import Control.Concurrent.Chan (Chan)
import qualified Control.Concurrent.Chan as Chan
import Control.Exception (bracket)
import Control.Monad (forever, unless, when)
import qualified Data.Aeson.Extended as A
import Data.Monoid (mempty, (<>))
import Data.Time (UTCTime)
import Data.Version (showVersion)
import qualified Options.Applicative as OA
import Patat.AutoAdvance
import qualified Patat.Images as Images
import Patat.Presentation
import qualified Paths_patat
import Prelude
import qualified System.Console.ANSI as Ansi
import System.Directory (doesFileExist,
getModificationTime)
import System.Exit (exitFailure, exitSuccess)
import qualified System.IO as IO
import qualified Text.Pandoc as Pandoc
import qualified Text.PrettyPrint.ANSI.Leijen as PP
data Options = Options
{ oFilePath :: !(Maybe FilePath)
, oForce :: !Bool
, oDump :: !Bool
, oWatch :: !Bool
, oVersion :: !Bool
} deriving (Show)
parseOptions :: OA.Parser Options
parseOptions = Options
<$> (OA.optional $ OA.strArgument $
OA.metavar "FILENAME" <>
OA.help "Input file")
<*> (OA.switch $
OA.long "force" <>
OA.short 'f' <>
OA.help "Force ANSI terminal" <>
OA.hidden)
<*> (OA.switch $
OA.long "dump" <>
OA.short 'd' <>
OA.help "Just dump all slides and exit" <>
OA.hidden)
<*> (OA.switch $
OA.long "watch" <>
OA.short 'w' <>
OA.help "Watch file for changes")
<*> (OA.switch $
OA.long "version" <>
OA.help "Display version info and exit" <>
OA.hidden)
parserInfo :: OA.ParserInfo Options
parserInfo = OA.info (OA.helper <*> parseOptions) $
OA.fullDesc <>
OA.header ("patat v" <> showVersion Paths_patat.version) <>
OA.progDescDoc (Just desc)
where
desc = PP.vcat
[ "Terminal-based presentations using Pandoc"
, ""
, "Controls:"
, "- Next slide: space, enter, l, right, pagedown"
, "- Previous slide: backspace, h, left, pageup"
, "- Go forward 10 slides: j, down"
, "- Go backward 10 slides: k, up"
, "- First slide: 0"
, "- Last slide: G"
, "- Jump to slide N: N followed by enter"
, "- Reload file: r"
, "- Quit: q"
]
parserPrefs :: OA.ParserPrefs
parserPrefs = OA.prefs OA.showHelpOnError
errorAndExit :: [String] -> IO a
errorAndExit msg = do
mapM_ (IO.hPutStrLn IO.stderr) msg
exitFailure
assertAnsiFeatures :: IO ()
assertAnsiFeatures = do
supports <- Ansi.hSupportsANSI IO.stdout
unless supports $ errorAndExit
[ "It looks like your terminal does not support ANSI codes."
, "If you still want to run the presentation, use `--force`."
]
main :: IO ()
main = do
options <- OA.customExecParser parserPrefs parserInfo
when (oVersion options) $ do
putStrLn (showVersion Paths_patat.version)
putStrLn $ "Using pandoc: " ++ Pandoc.pandocVersion
exitSuccess
filePath <- case oFilePath options of
Just fp -> return fp
Nothing -> OA.handleParseResult $ OA.Failure $
OA.parserFailure parserPrefs parserInfo OA.ShowHelpText mempty
errOrPres <- readPresentation filePath
pres <- either (errorAndExit . return) return errOrPres
unless (oForce options) assertAnsiFeatures
images <- traverse Images.new (psImages $ pSettings pres)
if oDump options
then dumpPresentation pres
else interactiveLoop options images pres
where
interactiveLoop :: Options -> Maybe Images.Handle -> Presentation -> IO ()
interactiveLoop options images pres0 =
interactively readPresentationCommand $ \commandChan0 -> do
commandChan <- case psAutoAdvanceDelay (pSettings pres0) of
Nothing -> return commandChan0
Just (A.FlexibleNum delay) -> autoAdvance delay commandChan0
mtime0 <- getModificationTime (pFilePath pres0)
when (oWatch options) $ do
_ <- forkIO $ watcher commandChan (pFilePath pres0) mtime0
return ()
let loop :: Presentation -> Maybe String -> IO ()
loop pres mbError = do
cleanup <- case mbError of
Nothing -> displayPresentation images pres
Just err -> displayPresentationError pres err
c <- Chan.readChan commandChan
update <- updatePresentation c pres
cleanup
case update of
ExitedPresentation -> return ()
UpdatedPresentation pres' -> loop pres' Nothing
ErroredPresentation err -> loop pres (Just err)
loop pres0 Nothing
interactively
:: (IO.Handle -> IO a)
-> (Chan a -> IO ())
-> IO ()
interactively reader app = bracket setup teardown $ \(_, _, _, chan) -> app chan
where
setup = do
chan <- Chan.newChan
echo <- IO.hGetEcho IO.stdin
buff <- IO.hGetBuffering IO.stdin
IO.hSetEcho IO.stdin False
IO.hSetBuffering IO.stdin IO.NoBuffering
Ansi.hideCursor
readerThreadId <- forkIO $ forever $
reader IO.stdin >>= Chan.writeChan chan
return (echo, buff, readerThreadId, chan)
teardown (echo, buff, readerThreadId, _chan) = do
Ansi.showCursor
Ansi.clearScreen
Ansi.setCursorPosition 0 0
killThread readerThreadId
IO.hSetEcho IO.stdin echo
IO.hSetBuffering IO.stdin buff
watcher :: Chan.Chan PresentationCommand -> FilePath -> UTCTime -> IO a
watcher chan filePath mtime0 = do
exists <- doesFileExist filePath
mtime1 <- if exists then getModificationTime filePath else return mtime0
when (mtime1 > mtime0) $ Chan.writeChan chan Reload
threadDelay (200 * 1000)
watcher chan filePath mtime1