Refactor G.Hooks.Loader - incl new useAff

src/Gargantext/Hooks/Loader.purs

 module Gargantext.Hooks.Loader where
 
-import Data.Maybe (Maybe(..), isNothing, maybe)
+import Data.Functor ((<$>))
+import Control.Monad ((=<<))
+import Data.Maybe (Maybe(..), isNothing, maybe, maybe')
 import Data.Tuple (fst)
 import Data.Tuple.Nested ((/\))
 import Gargantext.Prelude
@@ -10,36 +12,46 @@ import Reactix as R
 import Gargantext.Utils.Reactix as R2
 import Gargantext.Components.LoadingSpinner (loadingSpinner)
 
-useLoader :: forall path state. path -> (path -> Aff state) -> (state -> R.Element) -> R.Hooks R.Element
-useLoader path loader render = do
-  state <- R.useState' Nothing
-  loader' <- R.useMemo2 path loader (\_ -> loader path)
-  useLoaderEffect state loader'
-  pure $ maybe (loadingSpinner {}) render (fst state)
+useAff :: forall st. Aff st -> R.Hooks (Maybe st)
+useAff loader = do
+  (loaded /\ setLoaded) <- R.useState' Nothing
+  R.useEffect1 loader $ do
+    if isNothing loaded then
+      R2.affEffect "G.H.Loader.useAff" $
+        loader >>= (liftEffect <<< setLoaded <<< const <<< Just)
+    else pure R.nothing
+  pure loaded
+
+useLoader :: forall path st. path -> (path -> Aff st) -> (st -> R.Element) -> R.Hooks R.Element
+useLoader path loader render
+  =   maybe' (\_ -> loadingSpinner {}) render
+  <$> (useAff =<< R.useMemo2 path loader (\_ -> loader path))
 
-useLoader2 :: forall path state. R.State path -> (path -> Aff state) -> (state -> R.Element) -> R.Hooks R.Element
+useLoader2 :: forall path st. R.State path -> (path -> Aff st) -> (st -> R.Element) -> R.Hooks R.Element
 useLoader2 path loader render = do
   state <- R.useState' Nothing
   useLoaderEffect2 path state loader
   pure $ maybe (loadingSpinner {}) render (fst state)
   
-useLoaderEffect :: forall state. R.State (Maybe state) -> Aff state -> R.Hooks Unit
-useLoaderEffect (state /\ setState) loader = do
+useLoaderEffect :: forall state. Aff state -> R.State (Maybe state) -> R.Hooks Unit
+useLoaderEffect loader (state /\ setState) = do
   R.useEffect2 state loader $ do
     if isNothing state then
-      R2.affEffect "useLoader" $ loader >>= (liftEffect <<< setState <<< const <<< Just)
+      R2.affEffect "G.H.Loader.useLoader" $ loader >>= (liftEffect <<< setState <<< const <<< Just)
     else pure R.nothing
 
 useLoaderEffect' :: forall state. Aff state -> R.Hooks (R.State (Maybe state))
 useLoaderEffect' aff = do
   state <- R.useState' Nothing
-  useLoaderEffect state aff
+  useLoaderEffect aff state
   pure state
 
 useLoaderEffect2 :: forall st path. R.State path -> R.State (Maybe st) -> (path -> Aff st) -> R.Hooks Unit
-useLoaderEffect2 path state loader = useRepointer path loader >>= useLoaderEffect state
+useLoaderEffect2 path state loader = do
+  aff <- useRepointer path loader
+  useLoaderEffect aff state
 
 useRepointer :: forall path st. R.State path -> (path -> Aff st) -> R.Hooks (Aff st)
-useRepointer path@(path' /\ _) loader = R.useMemo1 path' (\_ -> loader path')
+useRepointer path@(path' /\ _) loader = R.useMemo2 loader path' (\_ -> loader path')