{-# LANGUAGE DeriveFunctor #-}
{-# LANGUAGE DeriveDataTypeable #-}
-- | Module with newtypes suitable to usage with @DerivingVia@ or standalone.
--
-- The newtypes are named after packages they wrap.
module Database.PostgreSQL.Simple.Newtypes (
    Aeson (..), getAeson,
) where

import Data.Typeable (Typeable)
import Database.PostgreSQL.Simple.ToField (ToField (..))
import Database.PostgreSQL.Simple.FromField (FromField (..), fromJSONField)

import qualified Data.Aeson as Aeson

-------------------------------------------------------------------------------
-- aeson
-------------------------------------------------------------------------------

-- | A newtype wrapper with 'ToField' and 'FromField' instances
-- based on 'Aeson.ToJSON' and 'Aeson.FromJSON' type classes from @aeson@.
--
-- Example using @DerivingVia@:
--
-- @
-- data Foo = Foo Int String
--   deriving stock (Eq, Show, Generic)            -- GHC built int
--   deriving anyclass ('Aeson.FromJSON', 'Aeson.ToJSON')          -- Derived using GHC Generics
--   deriving ('ToField', 'FromField') via 'Aeson' Foo   -- DerivingVia
-- @
--
-- Example using 'Aeson' newtype directly, for more ad-hoc queries
--
-- @
-- execute conn "INSERT INTO tbl (fld) VALUES (?)" (Only ('Aeson' x))
-- @
--  
--  @since 0.6.3
newtype Aeson a = Aeson a
  deriving (Aeson a -> Aeson a -> Bool
(Aeson a -> Aeson a -> Bool)
-> (Aeson a -> Aeson a -> Bool) -> Eq (Aeson a)
forall a. Eq a => Aeson a -> Aeson a -> Bool
forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a
$c== :: forall a. Eq a => Aeson a -> Aeson a -> Bool
== :: Aeson a -> Aeson a -> Bool
$c/= :: forall a. Eq a => Aeson a -> Aeson a -> Bool
/= :: Aeson a -> Aeson a -> Bool
Eq, Int -> Aeson a -> ShowS
[Aeson a] -> ShowS
Aeson a -> String
(Int -> Aeson a -> ShowS)
-> (Aeson a -> String) -> ([Aeson a] -> ShowS) -> Show (Aeson a)
forall a. Show a => Int -> Aeson a -> ShowS
forall a. Show a => [Aeson a] -> ShowS
forall a. Show a => Aeson a -> String
forall a.
(Int -> a -> ShowS) -> (a -> String) -> ([a] -> ShowS) -> Show a
$cshowsPrec :: forall a. Show a => Int -> Aeson a -> ShowS
showsPrec :: Int -> Aeson a -> ShowS
$cshow :: forall a. Show a => Aeson a -> String
show :: Aeson a -> String
$cshowList :: forall a. Show a => [Aeson a] -> ShowS
showList :: [Aeson a] -> ShowS
Show, ReadPrec [Aeson a]
ReadPrec (Aeson a)
Int -> ReadS (Aeson a)
ReadS [Aeson a]
(Int -> ReadS (Aeson a))
-> ReadS [Aeson a]
-> ReadPrec (Aeson a)
-> ReadPrec [Aeson a]
-> Read (Aeson a)
forall a. Read a => ReadPrec [Aeson a]
forall a. Read a => ReadPrec (Aeson a)
forall a. Read a => Int -> ReadS (Aeson a)
forall a. Read a => ReadS [Aeson a]
forall a.
(Int -> ReadS a)
-> ReadS [a] -> ReadPrec a -> ReadPrec [a] -> Read a
$creadsPrec :: forall a. Read a => Int -> ReadS (Aeson a)
readsPrec :: Int -> ReadS (Aeson a)
$creadList :: forall a. Read a => ReadS [Aeson a]
readList :: ReadS [Aeson a]
$creadPrec :: forall a. Read a => ReadPrec (Aeson a)
readPrec :: ReadPrec (Aeson a)
$creadListPrec :: forall a. Read a => ReadPrec [Aeson a]
readListPrec :: ReadPrec [Aeson a]
Read, Typeable, (forall a b. (a -> b) -> Aeson a -> Aeson b)
-> (forall a b. a -> Aeson b -> Aeson a) -> Functor Aeson
forall a b. a -> Aeson b -> Aeson a
forall a b. (a -> b) -> Aeson a -> Aeson b
forall (f :: * -> *).
(forall a b. (a -> b) -> f a -> f b)
-> (forall a b. a -> f b -> f a) -> Functor f
$cfmap :: forall a b. (a -> b) -> Aeson a -> Aeson b
fmap :: forall a b. (a -> b) -> Aeson a -> Aeson b
$c<$ :: forall a b. a -> Aeson b -> Aeson a
<$ :: forall a b. a -> Aeson b -> Aeson a
Functor)

getAeson :: Aeson a -> a
getAeson :: forall a. Aeson a -> a
getAeson (Aeson a
a) = a
a

instance Aeson.ToJSON a => ToField (Aeson a) where
    toField :: Aeson a -> Action
toField = ByteString -> Action
forall a. ToField a => a -> Action
toField (ByteString -> Action)
-> (Aeson a -> ByteString) -> Aeson a -> Action
forall b c a. (b -> c) -> (a -> b) -> a -> c
. a -> ByteString
forall a. ToJSON a => a -> ByteString
Aeson.encode (a -> ByteString) -> (Aeson a -> a) -> Aeson a -> ByteString
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Aeson a -> a
forall a. Aeson a -> a
getAeson

instance (Aeson.FromJSON a, Typeable a) => FromField (Aeson a) where
    fromField :: FieldParser (Aeson a)
fromField Field
f Maybe ByteString
bs = (a -> Aeson a) -> Conversion a -> Conversion (Aeson a)
forall a b. (a -> b) -> Conversion a -> Conversion b
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap a -> Aeson a
forall a. a -> Aeson a
Aeson (FieldParser a
forall a. (FromJSON a, Typeable a) => FieldParser a
fromJSONField Field
f Maybe ByteString
bs)