-- Copyright © 2011 National Institute of Aerospace / Galois, Inc.

-- | Example implementing an engine cooling control system.

{-# LANGUAGE RebindableSyntax #-}

module Main where

import Language.Copilot

import qualified Prelude as P

-- If the majority of the engine temperature probes exeeds 250 degrees, then

-- the cooler is engaged and remains engaged until the majority of the engine

-- temperature probes drop to 250 or below. Otherwise, trigger an immediate

-- shutdown of the engine.

engineMonitor :: Spec

engineMonitor = do

trigger "shutoff" (not ok) [arg maj]

where

vals = [ externW8 "tmp_probe_0" two51

, externW8 "tmp_probe_1" two51

, externW8 "tmp_probe_2" zero]

exceed = map (> 250) vals

maj = majority exceed

checkMaj = aMajority exceed maj

ok = alwaysBeen ((maj && checkMaj) ==> extern "cooler" cooler)

two51 = Just $ [251, 251] P.++ repeat (250 :: Word8)

zero = Just $ repeat (0 :: Word8)

cooler = Just $ [True, True] P.++ repeat False

main :: IO ()

main = interpret 10 engineMonitor