{-
# Main for beautifHOL, a HOL prettyprinter
# Based on the paper found at http://www.cs.indiana.edu/~lepike/pub_pages/pphol.html
# Lee Pike <lee-pike-@-gma-il-.com> (remove dashes)
# Jan 5, 2009
# Copyright 2008

#  This file is part of beautifHOL.
# BSD3.
-}

module Main where

import IO ( stdin, hGetContents )
import System ( getArgs )

import LexHOL
import ParHOL
--import SkelHOL
import PrintHOL
--import AbsHOL
import ErrM
import Data.List 

type ParseFun a = [Token] -> Err a

myLLexer = myLexer

runFile :: (Print a, Show a) => Flags -> ParseFun a -> FilePath -> IO ()
runFile flags p f = putStrLn f >> readFile f >>= run flags p

run :: (Print a, Show a) => Flags -> ParseFun a -> String -> IO ()
run flags p s = if s == ":q" then putStrLn "Bye."
                else let ts = myLLexer s 
                     in case p ts of
                          Bad s    -> do putStrLn "\nParse              Failed...\n"
                                         putStrLn "Tokens:"
                                         putStrLn $ show ts
                                         putStrLn s
                          Ok tree -> do putStrLn "\nParse Successful!"
                                        (if elem silentArg flags
                                         then return ()
                                         else showTree flags tree s)
                                        putStrLn ""
                                        putStrLn ""
                                        (if elem fileArg flags
                                         then return ()
                                         else do interactMsg
                                                 getLine >>= run flags pPROGRAM)

showTree :: (Show a, Print a) => Flags -> a -> String -> IO ()
showTree flags tree s = 
    do putStrFlg notree ast
       putStrFlg notree formulas 
       putStrLn $ printTree tree flags
       where ast = "\n[Abstract Syntax]\n" ++ show tree
             formulas = if elem showinputArg flags 
                        then "\n[Input formulas]\n" ++ s
                        else ""
             notree = not $ elem notreeArg flags
             putStrFlg b s = if b then putStrLn s else return ()


interactMsg :: IO ()
interactMsg = putStrLn "Reading from standard in.  Enter a formula or :q to quit."

main :: IO ()
main = do args <- getArgs
          case args of
            _ | "-help" `elem` args -> printHelp
              | "--help" `elem` args -> printHelp
              -- all args (except a possible file handle) recognizable?
              | not $ null $ (args \\ (getFile args)) \\ arglst -> printHelp
              -- no file given
              | (null $ getFile args) && (not $ fileArg `elem` args)
                  -> do interactMsg 
                        getLine >>= run flags pPROGRAM
              -- -f given but no file or non-file
              | null (getFile args) && fileArg `elem` args -> printHelp
              -- file given
              | otherwise -> runFile flags pPROGRAM $ head (getFile args)
                    where flags = intersect args arglst
                          getFile a = case (elemIndex fileArg a) of
                                        Nothing -> [] 
                                                  -- argsLst too short to have file?
                                        Just k -> if length a < k+2 
                                                  then []
                                                  -- get file
                                                  else [a !! (k+1)]


printHelp :: IO ()
printHelp = 
  mapM_ 
  putStrLn  
  [ "Usage: TestHOL [--silent] [--notree] [--showinput] " ++ 
    "[--nolabels] [--help] [--f filename]"
  , "where"
  , "--silent : Output nothing but whether parsing was successful." 
  , "--notree : Do not output the parse tree."
  , "--showinput : Ouput the input formula(s)."
  , "--nolabels : Do not label formulas."
  , "--help : Ouput this usage guide."
  , "--f filename : the optional text file containing the formulas to be pretty-printed.  Otherwise, start the program, and then enter formlas from standard-in."
  , ""
  , "All options not recognized are ignored."
  ]