{-# LANGUAGE ConstrainedClassMethods #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE NamedFieldPuns #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE QuasiQuotes #-}
{-# LANGUAGE TemplateHaskellQuotes #-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE NoImplicitPrelude #-}

module Data.Morpheus.Client.Declare.Fetch
  ( declareFetch,
  )
where

import Data.Morpheus.Client.Fetch (Fetch (..))
import Data.Morpheus.Client.Internal.Types
  ( FetchDefinition (..),
    TypeNameTH (..),
  )
import Data.Morpheus.CodeGen.Internal.TH
  ( applyCons,
    toCon,
    typeInstanceDec,
  )
import qualified Data.Text as T
import Language.Haskell.TH
  ( Dec,
    Q,
    Type,
    clause,
    cxt,
    funD,
    instanceD,
    normalB,
  )
import Relude hiding (ByteString, Type)

declareFetch :: Text -> FetchDefinition -> Q [Dec]
declareFetch :: Text -> FetchDefinition -> Q [Dec]
declareFetch Text
query FetchDefinition {Maybe TypeNameTH
clientArgumentsTypeName :: FetchDefinition -> Maybe TypeNameTH
clientArgumentsTypeName :: Maybe TypeNameTH
clientArgumentsTypeName, TypeNameTH
rootTypeName :: FetchDefinition -> TypeNameTH
rootTypeName :: TypeNameTH
rootTypeName} =
  Dec -> [Dec]
forall (f :: * -> *) a. Applicative f => a -> f a
pure (Dec -> [Dec]) -> Q Dec -> Q [Dec]
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> CxtQ -> TypeQ -> [Q Dec] -> Q Dec
instanceD ([TypeQ] -> CxtQ
cxt []) TypeQ
iHead [Q Dec]
methods
  where
    queryString :: String
queryString = Text -> String
T.unpack Text
query
    typeName :: TypeName
typeName = TypeNameTH -> TypeName
typename TypeNameTH
rootTypeName
    iHead :: TypeQ
iHead = Name -> [TypeName] -> TypeQ
forall con cons.
(ToName con, ToName cons) =>
con -> [cons] -> TypeQ
applyCons ''Fetch [TypeName
typeName]
    methods :: [Q Dec]
methods =
      [ Name -> [ClauseQ] -> Q Dec
funD 'fetch [[PatQ] -> BodyQ -> [Q Dec] -> ClauseQ
clause [] (ExpQ -> BodyQ
normalB [|__fetch queryString typeName|]) []],
        Dec -> Q Dec
forall (f :: * -> *) a. Applicative f => a -> f a
pure (Dec -> Q Dec) -> Dec -> Q Dec
forall a b. (a -> b) -> a -> b
$ Name -> Type -> Type -> Dec
typeInstanceDec ''Args (TypeName -> Type
forall a b. ToCon a b => a -> b
toCon TypeName
typeName) (Maybe TypeNameTH -> Type
argumentType Maybe TypeNameTH
clientArgumentsTypeName)
      ]

argumentType :: Maybe TypeNameTH -> Type
argumentType :: Maybe TypeNameTH -> Type
argumentType Maybe TypeNameTH
Nothing = String -> Type
forall a b. ToCon a b => a -> b
toCon (String
"()" :: String)
argumentType (Just TypeNameTH
clientTypeName) = TypeName -> Type
forall a b. ToCon a b => a -> b
toCon (TypeNameTH -> TypeName
typename TypeNameTH
clientTypeName)