{-# LANGUAGE DeriveFoldable     #-}
{-# LANGUAGE DeriveFunctor      #-}
{-# LANGUAGE DeriveGeneric      #-}
{-# LANGUAGE DeriveTraversable  #-}
{-# LANGUAGE DerivingStrategies #-}
{-# LANGUAGE DerivingVia        #-}
{-# LANGUAGE FlexibleInstances  #-}
module Data.Schema.Type
    ( SchemaF (..)
    , Schema
    , Type (..)
    , sumType
    , prodType
    ) where

import           Control.Applicative          ((<|>))
import           Data.Fix                     (Fix (..))
import           Data.Functor.Classes         (Eq1, Read1, Show1)
import           Data.Functor.Classes.Generic (FunctorClassesDefault (..))
import           GHC.Generics                 (Generic, Generic1)


data Type
    = TyBool
    | TyWord8
    | TyWord16
    | TyWord32
    | TyWord64
    | TyBin
    | TyFixedBin Int
    | TyName String
    deriving (Int -> Type -> ShowS
[Type] -> ShowS
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type DatatypeName = (String, String)

data SchemaF a
    = Empty
    | Atom Type
    | List a

    | Prod [a]
    | Field String a

    | Sum (Maybe DatatypeName) [a]
    | Con String a

    | Module String [a]
    | Schema [a]
    deriving (Int -> SchemaF a -> ShowS
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type Schema = Fix SchemaF

instance Semigroup Schema where
    <> :: Schema -> Schema -> Schema
(<>) = Schema -> Schema -> Schema
sumType

sumType :: Schema -> Schema -> Schema
sumType :: Schema -> Schema -> Schema
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da [Schema]
a)) (Fix (Sum Maybe DatatypeName
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a, Schema
b]

prodType :: Schema -> Schema -> Schema
prodType :: Schema -> Schema -> Schema
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a)) (Fix (Prod [Schema]
b)) = SchemaF Schema -> Schema
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b              = SchemaF Schema -> Schema
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prodType Schema
a (Fix (Prod [Schema]
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a Schema
b                           = SchemaF Schema -> Schema
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