import System.Exit

import Hm.Layout ( resolveLayout )
import Hm.Lex    ( Token, mkPosToken )
import Hm.Par    ( pExp, myLexer )
import Hm.Print  ( Print, printTree )

import Data.Text (Text)
import qualified Data.Text.IO as T

import qualified Data.Set as S

import TC (initialState, runCheck, infer, generalize)
import PostProcess (expToExp, runProcess)
import Pretty

inferType :: Text -> IO ()
inferType s = case pExp ts of
    Left err -> do
      putStrLn "\nParse              Failed...\n"
      putStrLn  "Tokens:"
      mapM_ (putStrLn . showPosToken . mkPosToken) ts
      putStrLn err
      exitFailure
    Right tree -> do
      putStrLn "\nParse Successful!"
      putStrLn (printTree tree)

      let action = runProcess (expToExp tree) S.empty >>= infer >>= generalize . snd
      let result = fst (runCheck initialState action)

      case result of
        Left  err -> print err
        Right res -> T.putStrLn (pretty res)
  where
    ts = init (resolveLayout True (myLexer s))
    showPosToken ((l,c),t) = concat [ show l, ":", show c, "\t", show t ]

main :: IO ()
main = T.getContents >>= inferType