implemented editStateL

src/Hamming/App/Types.hs

@@ -24,7 +24,7 @@ License along with this program.  If not, see
 
 |-}
 
-{-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE LambdaCase, TemplateHaskell #-}
 
 module Hamming.App.Types (
   -- * Application state data
@@ -35,6 +35,8 @@ module Hamming.App.Types (
   hammingCode,
   -- ** AppMode
   AppMode (..),
+  -- *** Lenses
+  editStateL,
   -- ** EditState,
   EditState (..),
   -- *** Lenses
@@ -52,18 +54,20 @@ module Hamming.App.Types (
 
 import Brick.Types (BrickEvent, EventM)
 import Data.Word (Word16)
+import Lens.Micro (Lens', lens)
 import Lens.Micro.TH (makeLenses)
 
 -- | The main state of the application
 data AppState = AppState
   { _appMode :: AppMode
   , _hammingCode :: Word16
-  }
+  } deriving (Eq, Show)
 
 -- | The application's main mode
 data AppMode
   = DisplayMode
   | EditMode EditState
+  deriving (Eq, Show)
 
 -- | The state of the editor
 data EditState = EditState
@@ -71,7 +75,7 @@ data EditState = EditState
   -- ^ The selected row number
   , _colNum :: Int
   -- ^ The selected column
-  }
+  } deriving (Eq, Show)
 
 -- | Identifies a resource
 type ResName = ()
@@ -90,6 +94,17 @@ concat <$> mapM makeLenses
   , ''EditState
   ]
 
+editStateL :: Lens' AppMode (Maybe EditState)
+editStateL = lens
+  ( \case
+    DisplayMode -> Nothing
+    EditMode s  -> Just s
+  )
+  ( const $ \case
+    Just s  -> EditMode s
+    Nothing -> DisplayMode
+  )
+
 -- | Initial application state
 initialState :: AppState
 initialState = AppState DisplayMode 0