Add editor syntax highlighting

src/TaskMachine/UI/TaskEdit.hs

@@ -8,13 +8,14 @@ module TaskMachine.UI.TaskEdit
   , updateTaskEdit
   ) where
 
-import qualified Brick              as B
-import qualified Brick.Widgets.Edit as B
-import qualified Data.Text.Zipper   as T
-import qualified Graphics.Vty       as VTY
+import qualified Brick               as B
+import qualified Brick.Widgets.Edit  as B
+import qualified Data.Text.Zipper    as T
+import qualified Graphics.Vty        as VTY
 import           Text.Megaparsec
 
 import           TaskMachine.Task
+import           TaskMachine.UI.Task
 
 data TaskEdit n = TaskEdit EditState (B.Editor String n)
   deriving (Show)
@@ -47,8 +48,14 @@ editedTask te = do
     Left parseError -> Left $ parseErrorPretty parseError
     Right task      -> Right task
 
+renderRow :: String -> B.Widget n
+renderRow s =
+  case parse pTask "" s of
+    Left _     -> B.str s
+    Right task -> renderTask task
+
 renderRows :: [String] -> B.Widget n
-renderRows = B.vBox . map B.str
+renderRows = B.vBox . map renderRow
 
 renderTaskEdit :: (Ord n, Show n) => Bool -> TaskEdit n -> B.Widget n
 renderTaskEdit focus (TaskEdit _ edit) = B.renderEditor renderRows focus edit

todo.txt

@@ -1,7 +1,7 @@
 x2018-10-23 c2018-09-18 Clean up file (adding creation/completion dates)
 - c2018-09-18 Purge - move completed tasks to a separate file
 x2018-10-23 c2018-09-28 Move cursor to beginning of task description when editing tasks
-- c2018-09-28 Syntax highlighting while editing tasks
+x2018-10-24 c2018-09-28 Syntax highlighting while editing tasks
 x2018-10-23 c2018-09-30 Display "-empty-" when TaskList is empty
 x2018-09-27 c2018-09-18 Quit using Esc or q
 x2018-09-29 c2018-09-28 Use B.EventM's MonadIO instance instead of B.suspendAndResume (facepalm)
@@ -11,5 +11,5 @@ x2018-09-30 c2018-09-18 Offer "retry" or "quit" +dialogue - syntax error in todo
 x2018-09-30 c2018-09-30 Custom exception messages
 x2018-10-24 c2018-10-23 Don't crash on parse errors etc.
 - c2018-10-24 Add "u" - undo and "z" - redo buttons
-- c2018-10-24 Redo coloring - maybe black-on-white color scheme in-editor?
+- c2018-10-24 Fix date coloring in editor
 x2018-10-24 c2018-10-24 Reverse ordering of completed tasks - most recent at the top