toggle between display/edit modes

src/Hamming/App/Events.hs

@@ -24,15 +24,18 @@ License along with this program.  If not, see
 
 |-}
 
+{-# LANGUAGE LambdaCase #-}
+
 module Hamming.App.Events (eventHandler) where
 
 import Brick.Main (halt)
-import Brick.Types (BrickEvent (VtyEvent))
+import Brick.Types (BrickEvent (VtyEvent), gets, modify)
 import Graphics.Vty.Input.Events
   ( Event (EvKey)
-  , Key (KChar)
+  , Key (KChar, KEsc)
   , Modifier (MCtrl)
   )
+import Lens.Micro ((^.), (.~))
 
 import Hamming.App.Types
 
@@ -40,6 +43,18 @@ import Hamming.App.Types
 eventHandler :: Handler
 eventHandler (VtyEvent (EvKey (KChar 'c') [MCtrl])) = halt
 eventHandler (VtyEvent (EvKey (KChar 'q') [])) = halt
-eventHandler _ = return ()
+eventHandler e = gets (^.appMode) >>= \case
+  DisplayMode -> displayHandler e
+  EditMode _  -> editHandler e
+
+displayHandler :: Handler
+displayHandler (VtyEvent (EvKey (KChar 'e') [])) =
+  modify $ appMode .~ EditMode initialEditor
+displayHandler _ = return ()
+
+editHandler :: Handler
+editHandler (VtyEvent (EvKey KEsc [])) =
+  modify $ appMode .~ DisplayMode
+editHandler _ = return ()
 
 --jl