module Engine.Window.Scroll
  ( Callback
  , callback

  , mkCallback
  ) where

import RIO

import Graphics.UI.GLFW qualified as GLFW
import RIO.App (appEnv)
import UnliftIO.Resource (ReleaseKey)
import UnliftIO.Resource qualified as Resource

import Engine.Events.Sink (MonadSink)
import Engine.Types (GlobalHandles(..))

type Callback m = Double -> Double -> m ()

callback
  :: MonadSink rs m
  => Callback m
  -> m ReleaseKey
callback :: forall rs (m :: * -> *).
MonadSink rs m =>
Callback m -> m ReleaseKey
callback Callback m
handler = do
  Window
window <- forall r (m :: * -> *) a. MonadReader r m => (r -> a) -> m a
asks forall a b. (a -> b) -> a -> b
$ GlobalHandles -> Window
ghWindow forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall env st. App env st -> env
appEnv
  forall (m :: * -> *) a.
MonadUnliftIO m =>
(UnliftIO m -> IO a) -> m a
withUnliftIO \UnliftIO m
ul ->
    Window -> Maybe ScrollCallback -> IO ()
GLFW.setScrollCallback Window
window forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a. a -> Maybe a
Just forall a b. (a -> b) -> a -> b
$ forall (m :: * -> *). UnliftIO m -> Callback m -> ScrollCallback
mkCallback UnliftIO m
ul Callback m
handler
  forall (m :: * -> *). MonadResource m => IO () -> m ReleaseKey
Resource.register forall a b. (a -> b) -> a -> b
$
    Window -> Maybe ScrollCallback -> IO ()
GLFW.setScrollCallback Window
window forall a. Maybe a
Nothing

mkCallback :: UnliftIO m -> Callback m -> GLFW.ScrollCallback
mkCallback :: forall (m :: * -> *). UnliftIO m -> Callback m -> ScrollCallback
mkCallback (UnliftIO forall a. m a -> IO a
ul) Callback m
action =
  \Window
_window Double
dx Double
dy ->
    forall a. m a -> IO a
ul forall a b. (a -> b) -> a -> b
$ Callback m
action Double
dx Double
dy