{-|
  Copyright   :  (C) 2013-2016, University of Twente,
                     2017-2019, Myrtle Software Ltd
                     2017     , Google Inc.
  License     :  BSD2 (see the file LICENSE)
  Maintainer  :  Christiaan Baaij <christiaan.baaij@gmail.com>

  __This is the <https://downloads.haskell.org/~ghc/latest/docs/html/users_guide/safe_haskell.html Safe> API only of "Clash.Prelude"__

  Clash is a functional hardware description language that borrows both its
  syntax and semantics from the functional programming language Haskell. The
  merits of using a functional language to describe hardware comes from the fact
  that combinational circuits can be directly modeled as mathematical functions
  and that functional languages lend themselves very well at describing and
  (de-)composing mathematical functions.

  This package provides:

  * Prelude library containing datatypes and functions for circuit design

  To use the library:

  * Import "Clash.Prelude"
  * Additionally import "Clash.Explicit.Prelude" if you want to design
    explicitly clocked circuits in a multi-clock setting

  For now, "Clash.Prelude" is also the best starting point for exploring the
  library. A preliminary version of a tutorial can be found in "Clash.Tutorial".
  Some circuit examples can be found in "Clash.Examples".
-}

{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE NoImplicitPrelude #-}

{-# LANGUAGE Safe #-}

{-# OPTIONS_HADDOCK show-extensions, not-home #-}

module Clash.Prelude.Safe
  ( -- * Creating synchronous sequential circuits
    mealy
  , mealyB
  , (<^>)
  , moore
  , mooreB
  , registerB
    -- * ROMs
  , asyncRom
  , asyncRomPow2
  , rom
  , romPow2
    -- * RAM primitives with a combinational read port
  , asyncRam
  , asyncRamPow2
    -- * BlockRAM primitives
  , blockRam
  , blockRamPow2
    -- ** BlockRAM read/write conflict resolution
  , readNew
    -- * Utility functions
  , isRising
  , isFalling
  , riseEvery
  , oscillate
    -- * Exported modules
    -- ** Synchronous signals
  , module Clash.Signal
  , module Clash.Signal.Delayed
    -- ** DataFlow interface
  , module Clash.Prelude.DataFlow
    -- ** Datatypes
    -- *** Bit vectors
  , module Clash.Sized.BitVector
  , module Clash.Prelude.BitIndex
  , module Clash.Prelude.BitReduction
    -- *** Arbitrary-width numbers
  , module Clash.Sized.Signed
  , module Clash.Sized.Unsigned
  , module Clash.Sized.Index
    -- *** Fixed point numbers
  , module Clash.Sized.Fixed
    -- *** Fixed size vectors
  , module Clash.Sized.Vector
    -- *** Perfect depth trees
  , module Clash.Sized.RTree
    -- ** Annotations
  , module Clash.Annotations.TopEntity
    -- ** Generics type-classes
  , Generic
  , Generic1
    -- ** Type-level natural numbers
  , module GHC.TypeLits
  , module GHC.TypeLits.Extra
  , module Clash.Promoted.Nat
  , module Clash.Promoted.Nat.Literals
  , module Clash.Promoted.Nat.TH
    -- ** Type-level strings
  , module Clash.Promoted.Symbol
    -- ** Type classes
    -- *** Clash
  , module Clash.Class.BitPack
  , module Clash.Class.Num
  , module Clash.Class.Resize
    -- *** Other
  , module Control.Applicative
  , module Data.Bits
      -- ** Exceptions
  , module Clash.XException
    -- ** Named types
  , module Clash.NamedTypes
    -- ** Hidden arguments
  , module Clash.Hidden
    -- ** Haskell Prelude
    -- $hiding
  , module Clash.HaskellPrelude
  )
where

import           Control.Applicative
import           Data.Bits
import           GHC.Generics (Generic, Generic1)

import           GHC.TypeLits
import           GHC.TypeLits.Extra
import           Clash.HaskellPrelude

import           Clash.Annotations.TopEntity
import           Clash.Class.BitPack
import           Clash.Class.Num
import           Clash.Class.Resize
import           Clash.Hidden
import           Clash.NamedTypes
import           Clash.Prelude.BitIndex
import           Clash.Prelude.BitReduction
import           Clash.Prelude.BlockRam
import qualified Clash.Explicit.Prelude.Safe as E
import           Clash.Prelude.Mealy         (mealy, mealyB, (<^>))
import           Clash.Prelude.Moore         (moore, mooreB)
import           Clash.Prelude.RAM           (asyncRam,asyncRamPow2)
import           Clash.Prelude.ROM           (asyncRom,asyncRomPow2,rom,romPow2)
import           Clash.Prelude.DataFlow
import           Clash.Promoted.Nat
import           Clash.Promoted.Nat.TH
import           Clash.Promoted.Nat.Literals
import           Clash.Promoted.Symbol
import           Clash.Sized.BitVector
import           Clash.Sized.Fixed
import           Clash.Sized.Index
import           Clash.Sized.RTree
import           Clash.Sized.Signed
import           Clash.Sized.Unsigned
import           Clash.Sized.Vector
import           Clash.Signal
import           Clash.Signal.Delayed
import           Clash.XException

{- $setup
>>> :set -XFlexibleContexts -XTypeApplications
>>> :m -Clash.Explicit.Prelude
>>> import Clash.Prelude.Safe
>>> let rP = registerB (8,8)
-}

{- $hiding
"Clash.Prelude" re-exports most of the Haskell "Prelude" with the exception of
the following: (++), (!!), concat, drop, foldl, foldl1, foldr, foldr1, head,
init, iterate, last, length, map, repeat, replicate, reverse, scanl, scanr,
splitAt, tail, take, unzip, unzip3, zip, zip3, zipWith, zipWith3.

It instead exports the identically named functions defined in terms of
'Clash.Sized.Vector.Vec' at "Clash.Sized.Vector".
-}

-- | Create a 'register' function for product-type like signals (e.g. '(Signal a, Signal b)')
--
-- > rP :: HiddenClockResetEnable dom
-- >    => (Signal dom Int, Signal dom Int)
-- >    -> (Signal dom Int, Signal dom Int)
-- > rP = registerB (8,8)
--
-- >>> simulateB @System rP [(1,1),(2,2),(3,3)] :: [(Int,Int)]
-- [(8,8),(1,1),(2,2),(3,3)...
-- ...
registerB
  :: ( HiddenClockResetEnable dom
     , NFDataX a
     , Bundle a )
  => a
  -> Unbundled dom a
  -> Unbundled dom a
registerB :: a -> Unbundled dom a -> Unbundled dom a
registerB = (KnownDomain dom =>
 Clock dom
 -> Reset dom
 -> Enable dom
 -> a
 -> Unbundled dom a
 -> Unbundled dom a)
-> a -> Unbundled dom a -> Unbundled dom a
forall (dom :: Domain) r.
HiddenClockResetEnable dom =>
(KnownDomain dom => Clock dom -> Reset dom -> Enable dom -> r) -> r
hideClockResetEnable KnownDomain dom =>
Clock dom
-> Reset dom
-> Enable dom
-> a
-> Unbundled dom a
-> Unbundled dom a
forall (dom :: Domain) a.
(KnownDomain dom, NFDataX a, Bundle a) =>
Clock dom
-> Reset dom
-> Enable dom
-> a
-> Unbundled dom a
-> Unbundled dom a
E.registerB
infixr 3 `registerB`
{-# INLINE registerB #-}

-- | Give a pulse when the 'Signal' goes from 'minBound' to 'maxBound'
isRising
  :: ( HiddenClockResetEnable dom
     , NFDataX a
     , Bounded a
     , Eq a )
  => a
  -- ^ Starting value
  -> Signal dom a
  -> Signal dom Bool
isRising :: a -> Signal dom a -> Signal dom Bool
isRising = (KnownDomain dom =>
 Clock dom
 -> Reset dom -> Enable dom -> a -> Signal dom a -> Signal dom Bool)
-> a -> Signal dom a -> Signal dom Bool
forall (dom :: Domain) r.
HiddenClockResetEnable dom =>
(KnownDomain dom => Clock dom -> Reset dom -> Enable dom -> r) -> r
hideClockResetEnable KnownDomain dom =>
Clock dom
-> Reset dom -> Enable dom -> a -> Signal dom a -> Signal dom Bool
forall (dom :: Domain) a.
(KnownDomain dom, NFDataX a, Bounded a, Eq a) =>
Clock dom
-> Reset dom -> Enable dom -> a -> Signal dom a -> Signal dom Bool
E.isRising
{-# INLINE isRising #-}

-- | Give a pulse when the 'Signal' goes from 'maxBound' to 'minBound'
isFalling
  :: ( HiddenClockResetEnable dom
     , NFDataX a
     , Bounded a
     , Eq a )
  => a
  -- ^ Starting value
  -> Signal dom a
  -> Signal dom Bool
isFalling :: a -> Signal dom a -> Signal dom Bool
isFalling = (KnownDomain dom =>
 Clock dom
 -> Reset dom -> Enable dom -> a -> Signal dom a -> Signal dom Bool)
-> a -> Signal dom a -> Signal dom Bool
forall (dom :: Domain) r.
HiddenClockResetEnable dom =>
(KnownDomain dom => Clock dom -> Reset dom -> Enable dom -> r) -> r
hideClockResetEnable KnownDomain dom =>
Clock dom
-> Reset dom -> Enable dom -> a -> Signal dom a -> Signal dom Bool
forall (dom :: Domain) a.
(KnownDomain dom, NFDataX a, Bounded a, Eq a) =>
Clock dom
-> Reset dom -> Enable dom -> a -> Signal dom a -> Signal dom Bool
E.isFalling
{-# INLINE isFalling #-}

-- | Give a pulse every @n@ clock cycles. This is a useful helper function when
-- combined with functions like @'Clash.Signal.regEn'@ or @'Clash.Signal.mux'@,
-- in order to delay a register by a known amount.
--
-- To be precise: the given signal will be @'False'@ for the next @n-1@ cycles,
-- followed by a single @'True'@ value:
--
-- >>> Prelude.last (sampleN @System 1025 (riseEvery d1024)) == True
-- True
-- >>> Prelude.or (sampleN @System 1024 (riseEvery d1024)) == False
-- True
--
-- For example, to update a counter once every 10 million cycles:
--
-- @
-- counter = 'Clash.Signal.regEn' 0 ('riseEvery' ('SNat' :: 'SNat' 10000000)) (counter + 1)
-- @
riseEvery
  :: HiddenClockResetEnable dom
  => SNat n
  -> Signal dom Bool
riseEvery :: SNat n -> Signal dom Bool
riseEvery = (KnownDomain dom =>
 Clock dom -> Reset dom -> Enable dom -> SNat n -> Signal dom Bool)
-> SNat n -> Signal dom Bool
forall (dom :: Domain) r.
HiddenClockResetEnable dom =>
(KnownDomain dom => Clock dom -> Reset dom -> Enable dom -> r) -> r
hideClockResetEnable KnownDomain dom =>
Clock dom -> Reset dom -> Enable dom -> SNat n -> Signal dom Bool
forall (dom :: Domain) (n :: Nat).
KnownDomain dom =>
Clock dom -> Reset dom -> Enable dom -> SNat n -> Signal dom Bool
E.riseEvery
{-# INLINE riseEvery #-}

-- | Oscillate a @'Bool'@ for a given number of cycles. This is a convenient
-- function when combined with something like @'regEn'@, as it allows you to
-- easily hold a register value for a given number of cycles. The input @'Bool'@
-- determines what the initial value is.
--
-- To oscillate on an interval of 5 cycles:
--
-- >>> sampleN @System 11 (oscillate False d5)
-- [False,False,False,False,False,False,True,True,True,True,True]
--
-- To oscillate between @'True'@ and @'False'@:
--
-- >>> sampleN @System 11 (oscillate False d1)
-- [False,False,True,False,True,False,True,False,True,False,True]
--
-- An alternative definition for the above could be:
--
-- >>> let osc' = register False (not <$> osc')
-- >>> sampleN @System 200 (oscillate False d1) == sampleN @System 200 osc'
-- True
oscillate
  :: HiddenClockResetEnable dom
  => Bool
  -> SNat n
  -> Signal dom Bool
oscillate :: Bool -> SNat n -> Signal dom Bool
oscillate = (KnownDomain dom =>
 Clock dom
 -> Reset dom -> Enable dom -> Bool -> SNat n -> Signal dom Bool)
-> Bool -> SNat n -> Signal dom Bool
forall (dom :: Domain) r.
HiddenClockResetEnable dom =>
(KnownDomain dom => Clock dom -> Reset dom -> Enable dom -> r) -> r
hideClockResetEnable KnownDomain dom =>
Clock dom
-> Reset dom -> Enable dom -> Bool -> SNat n -> Signal dom Bool
forall (dom :: Domain) (n :: Nat).
KnownDomain dom =>
Clock dom
-> Reset dom -> Enable dom -> Bool -> SNat n -> Signal dom Bool
E.oscillate
{-# INLINE oscillate #-}