{-# LANGUAGE Arrows #-}
{-# LANGUAGE RecordWildCards #-}

module Feedback where

-- essence-of-live-coding
import Util

-- test-framework
import Test.Framework

-- test-framework-quickcheck2
import Test.Framework.Providers.QuickCheck2

-- QuickCheck
import Test.QuickCheck

-- essence-of-live-coding
import LiveCoding

constCell :: Monad m => Int -> Cell m () Int
constCell cellState =
  Cell
    { cellStep = \state _ -> return (state, state)
    , ..
    }

test =
  testGroup
    "Feedback"
    [ testProperty
        "Migrates into feedback"
        CellMigrationSimulation
          { cell1 = constCell 23
          , cell2 = feedback [] $ proc ((), ns) -> do
              n <- constCell 42 -< ()
              returnA -< (sum ns, n : ns)
          , input1 = replicate 3 ()
          , input2 = replicate 3 ()
          , output1 = [23, 23, 23]
          , output2 = [0, 23, 46]
          }
    , testProperty
        "Migrates out of feedback"
        CellMigrationSimulation
          { cell1 = feedback [] $ proc ((), ns) -> do
              n <- constCell 23 -< ()
              returnA -< (sum ns, n : ns)
          , cell2 = constCell 42
          , input1 = replicate 3 ()
          , input2 = replicate 3 ()
          , output1 = [0, 23, 46]
          , output2 = [23, 23, 23]
          }
    ]