module Main(main) where
  
import Control.Exception
import Data.Enumerator (Enumerator, Iteratee, run, ($$))
import Data.Enumerator.Binary (enumHandle)
import Data.ByteString (ByteString)
import Data.Attoparsec.Enumerator (iterParser, ParseError, errorContexts)
import System.Exit
import System.IO (hSetBinaryMode,stdin)

import Network.EBus.Layer2

main :: IO ()
main = do
  -- * Select binary mode (True) or text mode (False) on a open handle. (See also openBinaryFile.) 
  hSetBinaryMode stdin True  
  loop 900

loop :: Int -> IO()
loop 0 = do
  print "finished"
loop n = do
  readAndDumpPacket
  loop (n - 1)


readAndDumpPacket :: IO()
readAndDumpPacket = do
  -- * run
  -- Run an iteratee until it finishes, and return either the final value (if it succeeded) or the error (if it failed).
  -- * run_
  -- Like run, except errors are converted to exceptions and thrown. Primarily useful for small scripts or other simple cases. 
  maybePacket <- run( enumSource $$ runParser )
  case maybePacket of  
    Right result -> do { print "Result"; print  result}
    Left  exc  -> case fromException (exc::SomeException) of
      Just e 
        | any (\ctx -> ctx == "demandInput") (errorContexts (e::ParseError)) -> do
          putStrLn "EOF reached"
          exitWith $ ExitFailure 1
        | otherwise -> do putStr "Other Error: "; print e
      _ -> putStr ""

enumSource :: Enumerator ByteString IO a
enumSource = enumHandle 1 stdin

runParser :: Iteratee ByteString IO EbusPacket
runParser = do
  p <- iterParser ebusParserLayer2
  return p