Fully functional (pun not intended) open questions

cards/example.txt

@@ -10,6 +10,6 @@ intrinsically photosensitive Retinal Ganglion Cell
 
 ---
 # Retina
-Part of the eye that turns light into _electrical neural impulses_.
+Part of the eye that turns _light_ into _electrical neural impulses_.
 
 ---

src/CardUI.hs

@@ -26,6 +26,7 @@ data CardState =
   | OpenQuestionState
   { _gapInput       :: Map Int String
   , _selectedGap    :: Int
+  , _nGaps          :: Int
   }
   deriving Show
 
@@ -43,13 +44,13 @@ makeLenses ''State
 defaultCardState :: Card -> CardState
 defaultCardState Definition{} = DefinitionState { _flipped = False }
 defaultCardState (MultipleChoice _ _ ics) = MultipleChoiceState { _selected = 0, _nChoices = length ics + 1, _tried = M.fromList [(i, False) | i <- [0..length ics]]}
-defaultCardState (OpenQuestion _ perforated) = OpenQuestionState { _gapInput = M.empty, _selectedGap = 0 }
+defaultCardState (OpenQuestion _ perforated) = OpenQuestionState { _gapInput = M.empty, _selectedGap = 0, _nGaps = nGapsInPerforated perforated }
 
 
 app :: App State Event Name
 app = App 
   { appDraw = drawUI
-  , appChooseCursor = neverShowCursor
+  , appChooseCursor = showFirstCursor
   , appHandleEvent = handleEvent
   , appStartEvent = return
   , appAttrMap = const theMap
@@ -120,15 +121,14 @@ drawOptions s options = case s ^. cardState of
 drawPerforated :: State -> Perforated -> Widget Name
 drawPerforated s p = drawSentence s $ perforatedToSentence p
 
-perforatedToSentence :: Perforated -> Sentence
-perforatedToSentence (P pre gap sentence) = Perforated pre gap sentence
-
 drawSentence :: State -> Sentence -> Widget Name
 drawSentence = drawSentence' 0
 drawSentence' i s (Normal text)             = str text
 drawSentence' i s (Perforated pre gap post) = case s ^. cardState of
-  OpenQuestionState {_gapInput = kvs } -> str pre <+> str gap <+> drawSentence' (i+1) s post
-    where gap = M.findWithDefault "default" i kvs
+  OpenQuestionState {_gapInput = kvs, _selectedGap=j } -> str pre <+> cursor (str gap) <+> drawSentence' (i+1) s post
+    where gap = M.findWithDefault "" i kvs
+          cursor :: Widget Name -> Widget Name
+          cursor = if i == j then showCursor () (Location (length gap, 0)) else id
   _ -> error "impossible"
 
 drawCardBox :: Widget Name -> Widget Name
@@ -169,11 +169,23 @@ handleEvent s (VtyEvent ev) = case ev of
             else continue $ s & cardState.flipped %~ not
         _ -> continue s
     
-    OpenQuestionState {_selectedGap = i} ->
+    OpenQuestionState {_selectedGap = i, _nGaps = n, _gapInput = kvs} ->
       case ev of
+        V.EvKey (V.KChar '\t') [] -> continue $ 
+          if i < n - 1
+            then s & (cardState.selectedGap) +~ 1
+            else s & (cardState.selectedGap) .~ 0
         V.EvKey (V.KChar c) [] -> continue $
           s & cardState.gapInput.at i.non "" %~ (++[c])    -- should prob. use snoc list for better efficiency
-        V.EvKey V.KEnter [] -> error (show (s^.cardState))
+        V.EvKey V.KEnter [] -> case s ^. currentCard of
+          OpenQuestion _ perforated -> if correct then next s else continue s
+            where correct :: Bool
+                  correct = foldSentenceIndex sent perf sentence
+                  sentence = perforatedToSentence perforated
+                  sent _ _ = True
+                  perf _ gap acc i = acc && gap == M.findWithDefault "" i kvs
+                  
+          _ -> error "impossible"
         V.EvKey V.KBS [] -> continue $ s & cardState.gapInput.ix i %~ backspace
           where backspace "" = ""
                 backspace xs = init xs
@@ -217,7 +229,7 @@ runCardUI input = do
 next :: State -> EventM Name (Next State)
 next s
   | s ^. index + 1 < length (s ^. cards) = continue . updateState $ s & index +~ 1
-  | otherwise                            = continue s
+  | otherwise                            = halt s
 
 previous :: State -> EventM Name (Next State)
 previous s | s ^. index > 0 = continue . updateState $ s & index -~ 1

src/MainMenuUI.hs

@@ -53,15 +53,22 @@ drawList s = hLimit 11 $
              L.renderList drawListElement True s
 
 drawListElement :: Bool -> String -> Widget Name
-drawListElement selected text = str text
+drawListElement selected text = 
+  hCenter $
+  attr $
+  str text
+  where attr = if selected then withAttr selectedAttr else id
 
 titleAttr :: AttrName
 titleAttr = attrName "title"
 
+selectedAttr :: AttrName
+selectedAttr = attrName "selected"
+
 theMap :: AttrMap
 theMap = attrMap V.defAttr
     [ (L.listAttr,            V.defAttr)
-    , (L.listSelectedAttr,    fg V.white `V.withStyle` V.underline)
+    , (selectedAttr,    fg V.white `V.withStyle` V.underline)
     , (titleAttr, fg V.yellow) ]
 
 handleEvent :: State -> BrickEvent Name Event -> EventM Name (Next State)

src/Parser.hs

@@ -16,9 +16,31 @@ data Answer = Answer Type String
 data Sentence = Perforated String String Sentence
               | Normal String
   deriving Show
+
+nGapsInSentence :: Sentence -> Int
+nGapsInSentence = nGapsInSentence' 0
+nGapsInSentence' acc (Normal s) = acc
+nGapsInSentence' acc (Perforated pre gap post) = nGapsInSentence' (1+acc) post
+
+foldSentence :: (String -> a) -> (String -> String -> a -> a) -> Sentence -> a
+foldSentence norm perf = f where
+  f (Normal text) = norm text
+  f (Perforated pre post sent) = perf pre post (f sent)
+
+foldSentenceIndex :: (String -> Int -> a) -> (String -> String -> a -> Int -> a) -> Sentence -> a
+foldSentenceIndex norm perf = f 0 where
+  f i (Normal text) = norm text i
+  f i (Perforated pre post sent) = perf pre post (f (i+1) sent) i
+
 data Perforated = P String String Sentence
   deriving Show
 
+perforatedToSentence :: Perforated -> Sentence
+perforatedToSentence (P pre gap sentence) = Perforated pre gap sentence
+
+nGapsInPerforated :: Perforated -> Int
+nGapsInPerforated = nGapsInSentence . perforatedToSentence
+
 --                     Word   Description
 data Card = Definition String String
           | OpenQuestion String Perforated