{-# LANGUAGE CPP                   #-}
{-# LANGUAGE FlexibleInstances     #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE TypeFamilies          #-}

{-# OPTIONS_GHC -fno-warn-orphans #-}

-- |
-- Module    :  Lens.Micro.Aeson.Internal
-- Copyright :  (c) Colin Woodbury 2015-2021, (c) Edward Kmett 2013-2014, (c) Paul Wilson 2012
-- License   :  BSD3
-- Maintainer:  Colin Woodbury <colingw@gmail.com>
--
-- These are stolen from `Lens.Micro.Platform` to avoid its dependencies.
-- They're altered to be specific to the Aeson context.
-- Creating instances for `microlens` typeclasses is generally warned
-- against, hence these instances are hidden here.

module Lens.Micro.Aeson.Internal where

#if !MIN_VERSION_base(4,8,0)
import           Control.Applicative
#endif
import           Data.Aeson (Value(..))
import qualified Data.Aeson.Key as Key
import qualified Data.Aeson.KeyMap as KM
import           Data.HashMap.Lazy as HashMap
import           Data.Text (Text)
import           Data.Vector as V
import           Lens.Micro.Internal

---

type instance Index Value = Text

type instance IxValue Value = Value

-- | Can only index into the contents of an `Object`,
-- which is a `HashMap`.
instance Ixed Value where
  ix :: Index Value -> Traversal' Value (IxValue Value)
ix Index Value
i IxValue Value -> f (IxValue Value)
f (Object Object
o) = Object -> Value
Object (Object -> Value) -> f Object -> f Value
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> Index Object
-> (IxValue Object -> f (IxValue Object)) -> Object -> f Object
forall m. Ixed m => Index m -> Traversal' m (IxValue m)
ix (Text -> Key
Key.fromText Text
Index Value
i) IxValue Value -> f (IxValue Value)
IxValue Object -> f (IxValue Object)
f Object
o
  ix Index Value
_ IxValue Value -> f (IxValue Value)
_ Value
v          = Value -> f Value
forall (f :: * -> *) a. Applicative f => a -> f a
pure Value
v
  {-# INLINE ix #-}

type instance Index   (HashMap Text Value) = Text

type instance IxValue (HashMap Text Value) = Value

-- | Straight-forward implementation.
instance Ixed (HashMap Text Value) where
  ix :: Index (HashMap Text Value)
-> Traversal' (HashMap Text Value) (IxValue (HashMap Text Value))
ix Index (HashMap Text Value)
k IxValue (HashMap Text Value) -> f (IxValue (HashMap Text Value))
f HashMap Text Value
m = case Text -> HashMap Text Value -> Maybe Value
forall k v. (Eq k, Hashable k) => k -> HashMap k v -> Maybe v
HashMap.lookup Text
Index (HashMap Text Value)
k HashMap Text Value
m of
    Just Value
v  -> (\Value
v' -> Text -> Value -> HashMap Text Value -> HashMap Text Value
forall k v.
(Eq k, Hashable k) =>
k -> v -> HashMap k v -> HashMap k v
HashMap.insert Text
Index (HashMap Text Value)
k Value
v' HashMap Text Value
m) (Value -> HashMap Text Value) -> f Value -> f (HashMap Text Value)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> IxValue (HashMap Text Value) -> f (IxValue (HashMap Text Value))
f Value
IxValue (HashMap Text Value)
v
    Maybe Value
Nothing -> HashMap Text Value -> f (HashMap Text Value)
forall (f :: * -> *) a. Applicative f => a -> f a
pure HashMap Text Value
m
  {-# INLINE ix #-}

type instance Index   (V.Vector a) = Int

type instance IxValue (V.Vector a) = a

-- | Also straight-forward. Only applicable for non-zero length `Vector`s.
instance Ixed (V.Vector a) where
  ix :: Index (Vector a) -> Traversal' (Vector a) (IxValue (Vector a))
ix Index (Vector a)
i IxValue (Vector a) -> f (IxValue (Vector a))
f Vector a
v
    | Int
0 Int -> Int -> Bool
forall a. Ord a => a -> a -> Bool
<= Int
Index (Vector a)
i Bool -> Bool -> Bool
&& Int
Index (Vector a)
i Int -> Int -> Bool
forall a. Ord a => a -> a -> Bool
< Vector a -> Int
forall a. Vector a -> Int
V.length Vector a
v = (\a
a -> Vector a
v Vector a -> [(Int, a)] -> Vector a
forall a. Vector a -> [(Int, a)] -> Vector a
V.// [(Int
Index (Vector a)
i, a
a)]) (a -> Vector a) -> f a -> f (Vector a)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> IxValue (Vector a) -> f (IxValue (Vector a))
f (Vector a
v Vector a -> Int -> a
forall a. Vector a -> Int -> a
V.! Int
Index (Vector a)
i)
    | Bool
otherwise = Vector a -> f (Vector a)
forall (f :: * -> *) a. Applicative f => a -> f a
pure Vector a
v
  {-# INLINE ix #-}

-- Thu Oct 21 11:49:16 2021
-- Adapted from lens-aeson to account for the aeson-2 update.

type instance Index (KM.KeyMap v) = Key.Key

type instance IxValue (KM.KeyMap v) = v

instance Ixed (KM.KeyMap v) where
  ix :: Index (KeyMap v) -> Traversal' (KeyMap v) (IxValue (KeyMap v))
ix Index (KeyMap v)
i IxValue (KeyMap v) -> f (IxValue (KeyMap v))
f KeyMap v
m = case Key -> KeyMap v -> Maybe v
forall v. Key -> KeyMap v -> Maybe v
KM.lookup Key
Index (KeyMap v)
i KeyMap v
m of
    Maybe v
Nothing -> KeyMap v -> f (KeyMap v)
forall (f :: * -> *) a. Applicative f => a -> f a
pure KeyMap v
m
    Just v
v  -> (\v
v' -> Key -> v -> KeyMap v -> KeyMap v
forall v. Key -> v -> KeyMap v -> KeyMap v
KM.insert Key
Index (KeyMap v)
i v
v' KeyMap v
m) (v -> KeyMap v) -> f v -> f (KeyMap v)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> IxValue (KeyMap v) -> f (IxValue (KeyMap v))
f v
IxValue (KeyMap v)
v

instance At (KM.KeyMap v) where
  at :: Index (KeyMap v) -> Lens' (KeyMap v) (Maybe (IxValue (KeyMap v)))
at Index (KeyMap v)
k Maybe (IxValue (KeyMap v)) -> f (Maybe (IxValue (KeyMap v)))
f = (Maybe v -> f (Maybe v)) -> Key -> KeyMap v -> f (KeyMap v)
forall (f :: * -> *) v.
Functor f =>
(Maybe v -> f (Maybe v)) -> Key -> KeyMap v -> f (KeyMap v)
KM.alterF Maybe v -> f (Maybe v)
Maybe (IxValue (KeyMap v)) -> f (Maybe (IxValue (KeyMap v)))
f Key
Index (KeyMap v)
k

instance Each (KM.KeyMap a) (KM.KeyMap b) a b where
  each :: (a -> f b) -> KeyMap a -> f (KeyMap b)
each = (a -> f b) -> KeyMap a -> f (KeyMap b)
forall (f :: * -> *) a b.
Traversable f =>
Traversal (f a) (f b) a b
traversed
  {-# INLINE each #-}