{-# LANGUAGE FunctionalDependencies #-}
{-# LANGUAGE PatternSynonyms #-}
{-# LANGUAGE Trustworthy #-}
{-# LANGUAGE ViewPatterns #-}

-- |
-- Module      :   Grisette.Core.Data.Class.Solvable
-- Copyright   :   (c) Sirui Lu 2021-2023
-- License     :   BSD-3-Clause (see the LICENSE file)
--
-- Maintainer  :   siruilu@cs.washington.edu
-- Stability   :   Experimental
-- Portability :   GHC only
module Grisette.Core.Data.Class.Solvable
  ( -- * Solvable type interface
    Solvable (..),
    pattern Con,
  )
where

import Control.DeepSeq
import Data.Hashable
import Data.String
import Data.Typeable
import Language.Haskell.TH.Syntax

-- $setup
-- >>> import Grisette.Core
-- >>> import Grisette.IR.SymPrim

-- | The class defines the creation and pattern matching of solvable type
-- values.
class IsString t => Solvable c t | t -> c where
  -- | Wrap a concrete value in a symbolic value.
  --
  -- >>> con True :: SymBool
  -- true
  con :: c -> t

  -- | Extract the concrete value from a symbolic value.
  --
  -- >>> conView (con True :: SymBool)
  -- Just True
  --
  -- >>> conView (ssym "a" :: SymBool)
  -- Nothing
  conView :: t -> Maybe c

  -- | Generate simply-named symbolic constants.
  --
  -- Two symbolic constants with the same name are the same symbolic constant,
  -- and will always be assigned with the same value by the solver.
  --
  -- >>> ssym "a" :: SymBool
  -- a
  -- >>> (ssym "a" :: SymBool) == ssym "a"
  -- True
  -- >>> (ssym "a" :: SymBool) == ssym "b"
  -- False
  -- >>> (ssym "a" :: SymBool) &&~ ssym "a"
  -- a
  ssym :: String -> t

  -- | Generate indexed symbolic constants.
  --
  -- Two symbolic constants with the same name but different indices are
  -- not the same symbolic constants.
  --
  -- >>> isym "a" 1 :: SymBool
  -- a@1
  isym :: String -> Int -> t

  -- | Generate simply-named symbolic constants with some extra information for
  -- disambiguation.
  --
  -- Two symbolic constants with the same name but different extra information
  -- (including info with different types) are considered to be different.
  --
  -- >>> sinfosym "a" "someInfo" :: SymInteger
  -- a:"someInfo"
  sinfosym :: (Typeable a, Ord a, Lift a, NFData a, Show a, Hashable a) => String -> a -> t

  -- | Generate indexed symbolic constants with some extra information for
  -- disambiguation.
  --
  -- Two symbolic constants with the same name and index but different extra
  -- information (including info with different types) are considered to be
  -- different.
  --
  -- >>> iinfosym "a" 1 "someInfo" :: SymInteger
  -- a@1:"someInfo"
  iinfosym :: (Typeable a, Ord a, Lift a, NFData a, Show a, Hashable a) => String -> Int -> a -> t

-- | Extract the concrete value from a solvable value with 'conView'.
--
-- >>> case con True :: SymBool of Con v -> v
-- True
pattern Con :: Solvable c t => c -> t
pattern Con c <-
  (conView -> Just c)
  where
    Con c = con c