module Env where

import qualified Code
import Control.Monad.IO.Class
import Control.Monad.Trans.State.Lazy
import qualified IR
import qualified Operators
import System.Console.Haskeline

data PrlgState =
  PrlgState
    { defs :: Code.Defs
    , ops :: Operators.Ops
    , strtable :: IR.StrTable
    }
  deriving (Show)

type PrlgEnv a = StateT PrlgState (InputT IO) a

withStrTable :: (IR.StrTable -> (IR.StrTable, a)) -> PrlgEnv a
withStrTable f = do
  st <- gets strtable
  let (st', x) = f st
  modify (\s -> s {strtable = st'})
  return x

findStruct :: String -> Int -> PrlgEnv IR.Id
findStruct str arity = do
  stri <- findAtom str
  return IR.Id {IR.str = stri, IR.arity = arity}

findAtom :: String -> PrlgEnv Int
findAtom = withStrTable . flip IR.strtablize