{-# OPTIONS_GHC -Wno-unrecognised-pragmas #-}
{-# HLINT ignore "Use tuple-section" #-}
module Commons where

import Data.List.Utils (split)
import GHC.IO.Handle (isEOF)
import Data.Map (Map, assocs, member, (!), fromList, empty, insert, toList, notMember)


data Module = Broadcaster { outputs :: [String] } |
              FlipFlop { state :: Bool, outputs :: [String] } |
              Conjonction { inputs :: Map String Bool, outputs :: [String] } deriving (Show)
type Modules = Map String Module


parseModule :: String -> [String] -> (String, Module)
parseModule "broadcaster" outputs = ("broadcaster", Broadcaster {outputs = outputs})
parseModule ('%': name) outputs = (name, FlipFlop {state = False, outputs = outputs})
parseModule ('&': name) outputs =
  (name, Conjonction {inputs = empty, outputs = outputs})

computeInputs'' :: String -> [String] -> Modules -> Modules
computeInputs'' _ [] modules = modules
computeInputs'' name (h: t) modules
  | notMember h modules = computeInputs'' name t modules
  | otherwise           =
      let output = modules ! h
      in case output of
         Conjonction i o -> computeInputs'' name t $ insert h Conjonction {inputs = insert name False i, outputs = o}
                                                            modules
         _               -> computeInputs'' name t modules

computeInputs' :: [(String, Module)] -> Modules -> Modules
computeInputs' [] modules = modules
computeInputs' ((name, m): t) modules = computeInputs' t $ computeInputs'' name (outputs m) modules

computeInputs :: Modules -> Modules
computeInputs modules = computeInputs' (toList modules) modules

parseModules :: [(String, Module)] -> IO Modules
parseModules otherModules = do done <- isEOF
                               if done then return $ computeInputs $ fromList otherModules
                               else do line <- getLine
                                       let (rawName: rawOutputs: _) = split " -> " line
                                       let cmodule = parseModule rawName $ split ", " rawOutputs
                                       parseModules $ otherModules ++ [cmodule]

parse :: IO Modules
parse = parseModules []