-- -----------------------------------------------------------------------------

-- 

-- Info.hs, part of Alex

--

-- (c) Simon Marlow 2003

--

-- Generate a human-readable rendition of the state machine.

--

-- ----------------------------------------------------------------------------}

module Info (infoDFA) where

import AbsSyn

import qualified Map

import qualified Data.IntMap as IntMap

import Util

-- -----------------------------------------------------------------------------

-- Generate a human readable dump of the state machine

infoDFA :: Int -> String -> DFA SNum Code -> ShowS

infoDFA _ func_nm dfa

  = str "Scanner : " . str func_nm . nl

  . str "States  : " . shows (length dfa_list) . nl

  . nl . infoDFA'

  where    

    dfa_list = Map.toAscList (dfa_states dfa)

    infoDFA' = interleave_shows nl (map infoStateN dfa_list)

    infoStateN (i,s) = str "State " . shows i . nl . infoState s

    infoState :: State SNum Code -> ShowS

    infoState (State accs out)

        = foldr (.) id (map infoAccept accs)

        . infoArr out . nl

    infoArr out

        = char '\t' . interleave_shows (str "\n\t")

                        (map infoTransition (IntMap.toAscList out))

    infoAccept (Acc p act lctx rctx)

        = str "\tAccept" . paren (shows p) . space

        . outputLCtx lctx . space

        . showRCtx rctx

        . (case act of

            Nothing   -> id

            Just code -> str " { " . str code . str " }")

        . nl

    infoTransition (char',state)

        = str (ljustify 8 (show char'))

        . str " -> "

        . shows state

    outputLCtx Nothing

          = id

    outputLCtx (Just set)

          = paren (show set ++) . char '^'

    -- outputArr arr

          -- = str "Array.array " . shows (bounds arr) . space

          -- . shows (assocs arr)