module FIR where

import Clash.Prelude


-- Dot product?
dotp :: SaturatingNum a
     => Vec (n + 1) a
     -> Vec (n + 1) a
     -> a
dotp as bs =
  fold boundedAdd              -- Sum up the resultant list
    (zipWith boundedMul as bs) -- Multiply corresponding values

fir
    :: (HiddenClockResetEnable dom
      , Default a
      , KnownNat n
      , SaturatingNum a
      , NFDataX a)
    => Vec (n+1) a -> Signal dom a -> Signal dom a
fir coeffs x_t = y_t
 where
  y_t = dotp coeffs <$> bundle xs
  xs  = window x_t

topEntity ::
     Clock System
  -> Reset System
  -> Enable System
  -> Signal System (Signed 16)
  -> Signal System (Signed 16)
topEntity = exposeClockResetEnable (fir (2:>3:>(-2):>8:>Nil))

testBench :: Signal System Bool
testBench = done
 where
  done = 
  rst  = tbsystemClockGen