@@ -1,43 +1,113 @@
1−{-|
1+{-# LANGUAGE FlexibleContexts #-}
2−Module: Reflex.Vty.Widget
2+{-# LANGUAGE FlexibleInstances #-}
3−Description: Basic set of widgets and building blocks for reflex-vty applications
3+{-# LANGUAGE FunctionalDependencies #-}
4−-}
4+{-# LANGUAGE GeneralizedNewtypeDeriving #-}
5−{-# Language UndecidableInstances #-}
5+{-# LANGUAGE LambdaCase #-}
6−
6+{-# LANGUAGE MultiParamTypeClasses #-}
7+{-# LANGUAGE OverloadedStrings #-}
8+{-# LANGUAGE RankNTypes #-}
9+{-# LANGUAGE RecursiveDo #-}
10+{-# LANGUAGE TypeFamilies #-}
7−module Reflex.Vty.Widget where
11+module Reflex.Vty.Widget
17+ , mainWidgetWithHandle
9import Control.Applicative (liftA2)
52import Control.Applicative (liftA2)
10import Control.Monad.Fix (MonadFix)
53import Control.Monad.Fix (MonadFix)
11−import Control.Monad.IO.Class (MonadIO)
54+import Control.Monad.Trans (lift)
12−import Control.Monad.Morph
55+import Control.Monad.Trans.Reader (ReaderT, runReaderT, asks, ask)
13−import Control.Monad.NodeId
14−import Control.Monad.Reader (ReaderT, ask, local, runReaderT)
15−import Control.Monad.Ref
56+import Control.Monad.Trans.Writer (WriterT, runWriterT, censor, tell)
16−import Control.Monad.Trans (MonadTrans, lift)
57+import Data.Char
59+import Data.Maybe (fromMaybe)
17−import Data.Set (Set)
60+import Data.Text (Text)
18−import qualified Data.Set as Set
61+import qualified Data.Text as T
19−import Graphics.Vty (Image)
62+import Graphics.Vty (Image, Attr)
20import qualified Graphics.Vty as V
63import qualified Graphics.Vty as V
21import Reflex
64import Reflex
22−import Reflex.Class ()
65+
23−import Reflex.Host.Class (MonadReflexCreateTrigger)
24import Reflex.Vty.Host
66import Reflex.Vty.Host
26−-- * Running a vty application
68+-- | The context within which a 'VtyWidget' runs
27−
69+data VtyWidgetCtx t = VtyWidgetCtx
70+ { _vtyWidgetCtx_size :: Dynamic t (Int,Int)
71+ -- ^ The width and height of the region allocated to the widget.
72+ , _vtyWidgetCtx_focus :: Dynamic t Bool
73+ -- ^ Whether the widget should behave as if it has focus for keyboard input.
74+ , _vtyWidgetCtx_input :: Event t VtyEvent
75+ -- ^ User input events that the widget's parent chooses to share. These will generally
76+ -- be filtered for relevance:
77+ -- * Keyboard inputs are restricted to focused widgets
78+ -- * Mouse inputs are restricted to the region in which the widget resides and are
79+ -- translated into its internal coordinates.
82+-- | The output of a 'VtyWidget'
83+data VtyWidgetOut t = VtyWidgetOut
84+ { _vtyWidgetOut_images :: Behavior t [Image]
85+ -- ^ The visual output of the 'VtyWidget'
86+ , _vtyWidgetOut_shutdown :: Event t ()
89+instance Reflex t => Semigroup (VtyWidgetOut t) where
90+ wo <> wo' = VtyWidgetOut
91+ { _vtyWidgetOut_images = _vtyWidgetOut_images wo <> _vtyWidgetOut_images wo'
92+ , _vtyWidgetOut_shutdown = _vtyWidgetOut_shutdown wo <> _vtyWidgetOut_shutdown wo'
95+instance (Reflex t) => Monoid (VtyWidgetOut t) where
96+ mempty = VtyWidgetOut mempty mempty
97+ mappend wo wo' = wo <> wo'
99+newtype VtyWidget t m a = VtyWidget { unVtyWidget :: WriterT (VtyWidgetOut t) (ReaderT (VtyWidgetCtx t) m) a }
100+ deriving (Functor, Applicative, Monad, MonadSample t, MonadHold t, MonadFix)
102+-- | Runs a 'VtyWidget' with a given context
103+runVtyWidget :: (Reflex t)
106+ -> m (a, VtyWidgetOut t)
107+runVtyWidget ctx w = runReaderT (runWriterT (unVtyWidget w)) ctx
28−-- | Sets up the top-level context for a vty widget and runs it with that context
109+-- | Sets up the top-level context for a 'VtyWidget' and runs it with that context
29−mainWidgetWithHandle
110+mainWidgetWithHandle :: V.Vty -> (forall t m. MonadVtyApp t m => VtyWidget t m ()) -> IO ()
35− , HasDisplayRegion t m
41mainWidgetWithHandle vty child =
111mainWidgetWithHandle vty child =
42 runVtyAppWithHandle vty $ \dr0 inp -> do
112 runVtyAppWithHandle vty $ \dr0 inp -> do
43 size <- holdDyn dr0 $ fforMaybe inp $ \case
113 size <- holdDyn dr0 $ fforMaybe inp $ \case
@@ -46,180 +116,59 @@ mainWidgetWithHandle vty child =
46 let inp' = fforMaybe inp $ \case
116 let inp' = fforMaybe inp $ \case
47 V.EvResize {} -> Nothing
117 V.EvResize {} -> Nothing
48 x -> Just x
118 x -> Just x
49− (shutdown, images) <- runThemeReader (constant V.defAttr) $
119+ let ctx = VtyWidgetCtx
50− runFocusReader (pure True) $
120+ { _vtyWidgetCtx_size = size
51− runDisplayRegion (fmap (\(w, h) -> Region 0 0 w h) size) $
121+ , _vtyWidgetCtx_input = inp'
52− runImageWriter $
122+ , _vtyWidgetCtx_focus = constDyn True
54− runInput inp' $ do
124+ ((), wo) <- runVtyWidget ctx child
55− tellImages . ffor (current size) $ \(w, h) -> [V.charFill V.defAttr ' ' w h]
57 return $ VtyResult
125 return $ VtyResult
58− { _vtyResult_picture = fmap (V.picForLayers . reverse) images
126+ { _vtyResult_picture = fmap (V.picForLayers . reverse) (_vtyWidgetOut_images wo)
59− , _vtyResult_shutdown = shutdown
127+ , _vtyResult_shutdown = _vtyWidgetOut_shutdown wo
62−-- | The output of a vty widget
63−data VtyWidgetOut t = VtyWidgetOut
64− { _vtyWidgetOut_shutdown :: Event t ()
67-- | Like 'mainWidgetWithHandle', but uses a default vty configuration
130-- | Like 'mainWidgetWithHandle', but uses a default vty configuration
70− ( MonadVtyApp t m
131+mainWidget :: (forall t m. MonadVtyApp t m => VtyWidget t m ()) -> IO ()
73− , HasDisplayRegion t m
79mainWidget child = do
132mainWidget child = do
80 vty <- getDefaultVty
133 vty <- getDefaultVty
81 mainWidgetWithHandle vty child
134 mainWidgetWithHandle vty child
83−-- * Input Events
136+class (Reflex t, Monad m) => HasDisplaySize t m | m -> t where
137+ displaySize :: m (Dynamic t (Int, Int))
139+instance (Reflex t, Monad m) => HasDisplaySize t (VtyWidget t m) where
140+ displaySize = VtyWidget . lift $ asks _vtyWidgetCtx_size
142+displayWidth :: HasDisplaySize t m => m (Dynamic t Int)
143+displayWidth = fmap fst <$> displaySize
85−-- | A class for things that can receive vty events as input
145+displayHeight :: HasDisplaySize t m => m (Dynamic t Int)
146+displayHeight = fmap snd <$> displaySize
86−class HasInput t m | m -> t where
148+class HasVtyInput t m | m -> t where
87 input :: m (Event t VtyEvent)
149 input :: m (Event t VtyEvent)
88− default input :: (f m' ~ m, Monad m', MonadTrans f, HasInput t m') => m (Event t VtyEvent)
90− -- | User input events that the widget's parent chooses to share. These will generally
91− -- be filtered for relevance.
92− localInput :: (Event t VtyEvent -> Event t VtyEvent) -> m a -> m a
93− default localInput :: (f m' ~ m, Monad m', MFunctor f, HasInput t m') => (Event t VtyEvent -> Event t VtyEvent) -> m a -> m a
94− localInput f = hoist (localInput f)
96−instance (Reflex t, Monad m) => HasInput t (Input t m) where
98− localInput f (Input m) = Input $ local f m
100−-- | A widget that can receive input events. See 'Graphics.Vty.Event'
101−newtype Input t m a = Input
102− { unInput :: ReaderT (Event t VtyEvent) m a
114−instance (Adjustable t m, MonadHold t m, Reflex t) => Adjustable t (Input t m) where
115− runWithReplace a0 a' = Input $ runWithReplace (unInput a0) $ fmap unInput a'
116− traverseIntMapWithKeyWithAdjust f dm0 dm' = Input $
117− traverseIntMapWithKeyWithAdjust (\k v -> unInput (f k v)) dm0 dm'
118− traverseDMapWithKeyWithAdjust f dm0 dm' = Input $ do
119− traverseDMapWithKeyWithAdjust (\k v -> unInput (f k v)) dm0 dm'
120− traverseDMapWithKeyWithAdjustWithMove f dm0 dm' = Input $ do
121− traverseDMapWithKeyWithAdjustWithMove (\k v -> unInput (f k v)) dm0 dm'
123−deriving instance MonadReflexCreateTrigger t m => MonadReflexCreateTrigger t (Input t m)
124−deriving instance NotReady t m => NotReady t (Input t m)
125−deriving instance PerformEvent t m => PerformEvent t (Input t m)
126−deriving instance PostBuild t m => PostBuild t (Input t m)
127−deriving instance TriggerEvent t m => TriggerEvent t (Input t m)
128−instance HasImageWriter t m => HasImageWriter t (Input t m)
129−instance HasDisplayRegion t m => HasDisplayRegion t (Input t m)
130−instance HasFocusReader t m => HasFocusReader t (Input t m)
132−instance MonadTrans (Input t) where
133− lift f = Input $ lift f
135−instance MFunctor (Input t) where
136− hoist f = Input . hoist f . unInput
138−instance MonadNodeId m => MonadNodeId (Input t m)
140−-- | Runs an 'Input' with a given context
146−runInput e w = runReaderT (unInput w) e
148−-- ** Filtering input
150−-- | Type synonym for a key and modifier combination
151−type KeyCombo = (V.Key, [V.Modifier])
153−-- | Emits an event that fires on a particular key press (without modifiers)
154−key :: (Monad m, Reflex t, HasInput t m) => V.Key -> m (Event t KeyCombo)
155−key = keyCombos . Set.singleton . (,[])
157−-- | Emits an event that fires on particular key presses (without modifiers)
158−keys :: (Monad m, Reflex t, HasInput t m) => [V.Key] -> m (Event t KeyCombo)
159−keys = keyCombos . Set.fromList . fmap (,[])
161−-- | Emit an event that fires whenever the provided key combination occurs
163− :: (Reflex t, Monad m, HasInput t m)
165− -> m (Event t KeyCombo)
166−keyCombo = keyCombos . Set.singleton
168−-- | Emit an event that fires whenever any of the provided key combinations occur
170− :: (Reflex t, Monad m, HasInput t m)
172− -> m (Event t KeyCombo)
175− return $ fforMaybe i $ \case
176− V.EvKey k m -> if Set.member (k, m) ks
181−-- | Filter the keyboard input that a child widget may receive
151+instance (Reflex t, Monad m) => HasVtyInput t (VtyWidget t m) where
182−filterKeys :: (Reflex t, HasInput t m) => (KeyCombo -> Bool) -> m a -> m a
152+ input = VtyWidget . lift $ asks _vtyWidgetCtx_input
183−filterKeys f x = localInput (ffilter (\case
153+
184− V.EvKey k mods -> f (k, mods)
154+class HasFocus t m | m -> t where
185− _ -> True)) x
155+ focus :: m (Dynamic t Bool)
187−-- | Filter mouse input events based on whether they target a particular region
188−-- and translate them to the internal coordinate system of that region.
190−-- NB: Non-mouse events are passed through unfiltered and unchanged
191−mouseInRegion :: Region -> VtyEvent -> Maybe VtyEvent
192−mouseInRegion (Region l t w h) e = case e of
193− V.EvMouseDown x y btn m -> mouse (\u v -> V.EvMouseDown u v btn m) x y
194− V.EvMouseUp x y btn -> mouse (\u v -> V.EvMouseUp u v btn) x y
201− , y >= t + h ] = Nothing
203− Just (con (x - l) (y - t))
205−-- | Filter mouse input outside the current display region and
206−-- all input if the region is not focused
208− :: (HasDisplayRegion t m, HasFocusReader t m, HasInput t m)
209− => m (Event t VtyEvent)
210−inputInFocusedRegion = do
212− reg <- current <$> askRegion
213− foc <- current <$> focus
214− pure $ fmapMaybe id $ attachWith filterInput ((,) <$> reg <*> foc) inp
216− filterInput (r, f) = \case
217− V.EvKey {} | not f -> Nothing
218− x -> mouseInRegion r x
220−-- * Getting and setting the display region
157+instance (Reflex t, Monad m) => HasFocus t (VtyWidget t m) where
158+ focus = VtyWidget . lift $ asks _vtyWidgetCtx_focus
160+class (Reflex t, Monad m) => ImageWriter t m | m -> t where
161+ tellImages :: Behavior t [Image] -> m ()
163+instance (Reflex t, Monad m) => ImageWriter t (VtyWidget t m) where
164+ tellImages imgs = VtyWidget $ tell (mempty { _vtyWidgetOut_images = imgs })
166+class (Reflex t, Monad m) => Shutdown t m where
167+ tellShutdown :: Event t () -> m ()
169+instance (Reflex t, Monad m) => Shutdown t (VtyWidget t m) where
170+ tellShutdown sd = VtyWidget $ tell (mempty { _vtyWidgetOut_shutdown = sd })
222−-- | A chunk of the display area
223data Region = Region
172data Region = Region
224 { _region_left :: Int
173 { _region_left :: Int
225 , _region_top :: Int
174 , _region_top :: Int
@@ -228,334 +177,393 @@ data Region = Region
229 deriving (Show, Read, Eq, Ord)
178 deriving (Show, Read, Eq, Ord)
231−-- | A region that occupies no space.
233−nilRegion = Region 0 0 0 0
235−-- | The width and height of a 'Region'
236regionSize :: Region -> (Int, Int)
180regionSize :: Region -> (Int, Int)
237regionSize (Region _ _ w h) = (w, h)
181regionSize (Region _ _ w h) = (w, h)
239−-- | Produces an 'Image' that fills a region with space characters
183+pane
240−regionBlankImage :: V.Attr -> Region -> Image
241−regionBlankImage attr r@(Region _ _ width height) =
242− withinImage r $ V.charFill attr ' ' width height
244−-- | A class for things that know their own display size dimensions
245−class (Reflex t, Monad m) => HasDisplayRegion t m | m -> t where
184+ :: (Reflex t, Monad m)
246− -- | Retrieve the display region
185+ => Dynamic t Region -- ^ Region into which we should draw the widget (in coordinates relative to our own)
247− askRegion :: m (Dynamic t Region)
186+ -> Dynamic t Bool -- ^ Whether the widget should be focused when the parent is.
248− default askRegion :: (f m' ~ m, MonadTrans f, HasDisplayRegion t m') => m (Dynamic t Region)
187+ -> VtyWidget t m a
249− askRegion = lift askRegion
188+ -> VtyWidget t m a
250− -- | Run an action in a local region, by applying a transformation to the region
189+pane reg foc child = VtyWidget $ do
251− localRegion :: (Dynamic t Region -> Dynamic t Region) -> m a -> m a
190+ ctx <- lift ask
252− default localRegion :: (f m' ~ m, Monad m', MFunctor f, HasDisplayRegion t m') => (Dynamic t Region -> Dynamic t Region) -> m a -> m a
191+ let ctx' = VtyWidgetCtx
253− localRegion f = hoist (localRegion f)
192+ { _vtyWidgetCtx_input = leftmost -- TODO: think about this leftmost more.
254−
193+ [ fmapMaybe id $
255−-- | Retrieve the display width
194+ attachWith (\(r,f) e -> filterInput r f e)
256−displayWidth :: HasDisplayRegion t m => m (Dynamic t Int)
195+ (liftA2 (,) (current reg) (current foc))
257−displayWidth = fmap _region_width <$> askRegion
196+ (_vtyWidgetCtx_input ctx)
259−-- | Retrieve the display height
198+ , _vtyWidgetCtx_focus = liftA2 (&&) (_vtyWidgetCtx_focus ctx) foc
260−displayHeight :: HasDisplayRegion t m => m (Dynamic t Int)
199+ , _vtyWidgetCtx_size = fmap regionSize reg }
261−displayHeight = fmap _region_height <$> askRegion
200+ (result, wo) <- lift . lift $ runVtyWidget ctx' child
262−
201+ let images = _vtyWidgetOut_images wo
263−instance HasDisplayRegion t m => HasDisplayRegion t (ReaderT x m)
202+ images' = liftA2 (\r is -> map (withinImage r) is) (current reg) images
264−instance HasDisplayRegion t m => HasDisplayRegion t (BehaviorWriterT t x m)
203+ wo' = wo { _vtyWidgetOut_images = images' }
265−instance HasDisplayRegion t m => HasDisplayRegion t (DynamicWriterT t x m)
204+ tell wo'
266−instance HasDisplayRegion t m => HasDisplayRegion t (EventWriterT t x m)
205+ return result
267−instance HasDisplayRegion t m => HasDisplayRegion t (NodeIdT m)
206+ where
268−
207+ -- Filters input such that:
269−-- | A widget that has access to a particular region of the vty display
208+ -- * unfocused widgets receive no key events
270−newtype DisplayRegion t m a = DisplayRegion
209+ -- * mouse inputs outside the region are ignored
271− { unDisplayRegion :: ReaderT (Dynamic t Region) m a }
210+ -- * mouse inputs inside the region have their coordinates translated
272− deriving
211+ -- such that (0,0) is the top-left corner of the region
273− ( Functor
212+ filterInput :: Region -> Bool -> VtyEvent -> Maybe VtyEvent
274− , Applicative
213+ filterInput (Region l t w h) focused e = case e of
275− , Monad
214+ V.EvKey _ _ | not focused -> Nothing
276− , MonadFix
215+ V.EvMouseDown x y btn m -> mouse (\u v -> V.EvMouseDown u v btn m) x y
277− , MonadHold t
216+ V.EvMouseUp x y btn -> mouse (\u v -> V.EvMouseUp u v btn) x y
278− , MonadIO
217+ _ -> Just e
279− , MonadRef
218+ where
280− , MonadSample t
219+ mouse con x y
283−instance (Monad m, Reflex t) => HasDisplayRegion t (DisplayRegion t m) where
222+ , x >= l + w
284− askRegion = DisplayRegion ask
223+ , y >= t + h ] = Nothing
285− localRegion f = DisplayRegion . local f . unDisplayRegion
224+ | otherwise =
286−
225+ Just (con (x - l) (y - t))
287−deriving instance MonadReflexCreateTrigger t m => MonadReflexCreateTrigger t (DisplayRegion t m)
226+
288−deriving instance NotReady t m => NotReady t (DisplayRegion t m)
227+data Drag = Drag
289−deriving instance PerformEvent t m => PerformEvent t (DisplayRegion t m)
228+ { _drag_from :: (Int, Int) -- ^ Where the drag began
290−deriving instance PostBuild t m => PostBuild t (DisplayRegion t m)
229+ , _drag_to :: (Int, Int) -- ^ Where the mouse currently is
291−deriving instance TriggerEvent t m => TriggerEvent t (DisplayRegion t m)
230+ , _drag_button :: V.Button -- ^ Which mouse button is dragging
292−instance HasImageWriter t m => HasImageWriter t (DisplayRegion t m)
231+ , _drag_modifiers :: [V.Modifier] -- ^ What modifiers are held
293−instance HasFocusReader t m => HasFocusReader t (DisplayRegion t m)
232+ , _drag_end :: Bool -- ^ Whether the drag ended (the mouse button was released)
295−instance (Adjustable t m, MonadFix m, MonadHold t m) => Adjustable t (DisplayRegion t m) where
234+ deriving (Eq, Ord, Show)
296− runWithReplace (DisplayRegion a) e = DisplayRegion $ runWithReplace a $ fmap unDisplayRegion e
235+
297− traverseIntMapWithKeyWithAdjust f m e = DisplayRegion $ traverseIntMapWithKeyWithAdjust (\k v -> unDisplayRegion $ f k v) m e
236+drag
298− traverseDMapWithKeyWithAdjust f m e = DisplayRegion $ traverseDMapWithKeyWithAdjust (\k v -> unDisplayRegion $ f k v) m e
237+ :: (Reflex t, MonadFix m, MonadHold t m)
299− traverseDMapWithKeyWithAdjustWithMove f m e = DisplayRegion $ traverseDMapWithKeyWithAdjustWithMove (\k v -> unDisplayRegion $ f k v) m e
238+ => V.Button
300−
239+ -> VtyWidget t m (Event t Drag)
301−instance MonadTrans (DisplayRegion t) where
240+drag btn = do
302− lift = DisplayRegion . lift
241+ inp <- input
303−
242+ let f :: Drag -> V.Event -> Maybe Drag
304−instance MFunctor (DisplayRegion t) where
243+ f (Drag from _ _ mods end) = \case
305− hoist f = DisplayRegion . hoist f . unDisplayRegion
244+ V.EvMouseDown x y btn' mods'
306−
245+ | end -> Just $ Drag (x,y) (x,y) btn' mods' False
307−instance MonadNodeId m => MonadNodeId (DisplayRegion t m)
246+ | btn == btn' -> Just $ Drag from (x,y) btn mods' False
308−
247+ | otherwise -> Nothing -- Ignore other buttons.
309−-- | Run a 'DisplayRegion' action with a given 'Region'
248+ V.EvMouseUp x y (Just btn')
310−runDisplayRegion
249+ | end -> Nothing
250+ | btn == btn' -> Just $ Drag from (x,y) btn mods True
251+ | otherwise -> Nothing
252+ V.EvMouseUp x y Nothing -- Terminal doesn't specify mouse up button,
253+ -- assume it's the right one.
255+ | otherwise -> Just $ Drag from (x,y) btn mods True
257+ rec let newDrag = attachWithMaybe f (current dragD) inp
258+ dragD <- holdDyn (Drag (0,0) (0,0) btn [] True) -- gross, but ok because it'll never be produced.
260+ return (updated dragD)
311 :: (Reflex t, Monad m)
263 :: (Reflex t, Monad m)
312− => Dynamic t Region
264+ => V.Button
313− -> DisplayRegion t m a
265+ -> VtyWidget t m (Event t VtyEvent)
314− -> m a
266+mouseDown btn = do
315−runDisplayRegion r = flip runReaderT r . unDisplayRegion
267+ i <- input
268+ return $ fforMaybe i $ \x -> case x of
269+ V.EvMouseDown _ _ btn' _ -> if btn == btn' then Just x else Nothing
317−-- * Getting focus state
272+-- | A plain split of the available space into vertically stacked panes.
273+-- No visual separator is built in here.
274+splitV :: (Reflex t, Monad m)
275+ => Dynamic t (Int -> Int)
276+ -- ^ Function used to determine size of first pane based on available size
277+ -> Dynamic t (Bool, Bool)
278+ -- ^ How to focus the two sub-panes, given that we are focused.
280+ -- ^ Widget for first pane
282+ -- ^ Widget for second pane
283+ -> VtyWidget t m (a,b)
284+splitV sizeFunD focD wA wB = do
286+ let regA = (\f (w,h) -> Region 0 0 w (f h)) <$> sizeFunD <*> sz
287+ regB = (\(w,h) (Region _ _ _ hA) -> Region 0 hA w (h - hA)) <$> sz <*> regA
288+ ra <- pane regA (fst <$> focD) wA
289+ rb <- pane regB (snd <$> focD) wB
292+-- | A split of the available space into two parts with a draggable separator.
293+-- Starts with half the space allocated to each, and the first pane has focus.
294+-- Clicking in a pane switches focus.
295+splitVDrag :: (Reflex t, MonadFix m, MonadHold t m)
299+ -> VtyWidget t m (a,b)
300+splitVDrag wS wA wB = do
302+ (_, h0) <- sample $ current sz
303+ dragE <- drag V.BLeft
304+ let splitter0 = h0 `div` 2
305+ rec splitterCheckpoint <- holdDyn splitter0 $ leftmost [fst <$> ffilter snd dragSplitter, resizeSplitter]
306+ splitterPos <- holdDyn splitter0 $ leftmost [fst <$> dragSplitter, resizeSplitter]
307+ splitterFrac <- holdDyn ((1::Double) / 2) $ ffor (attach (current sz) (fst <$> dragSplitter)) $ \((_,h),x) ->
308+ fromIntegral x / fromIntegral h
309+ let dragSplitter = fforMaybe (attach (current splitterCheckpoint) dragE) $
310+ \(splitterY, Drag (_, fromY) (_, toY) _ _ end) ->
311+ if splitterY == fromY then Just (toY, end) else Nothing
312+ regA = (\(w,_) sp -> Region 0 0 w sp) <$> sz <*> splitterPos
313+ regS = (\(w,_) sp -> Region 0 sp w 1) <$> sz <*> splitterPos
314+ regB = (\(w,h) sp -> Region 0 (sp + 1) w (h - sp - 1)) <$> sz <*> splitterPos
315+ resizeSplitter = ffor (attach (current splitterFrac) (updated sz)) $
316+ \(frac, (_,h)) -> round (frac * fromIntegral h)
317+ focA <- holdDyn True $ leftmost
321+ (mA, rA) <- pane regA focA $ withMouseDown wA
322+ pane regS (pure False) wS
323+ (mB, rB) <- pane regB (not <$> focA) $ withMouseDown wB
326+ withMouseDown x = do
327+ m <- mouseDown V.BLeft
331+-- | Fill the background with a particular character.
332+fill :: (Reflex t, Monad m) => Char -> VtyWidget t m ()
335+ let fillImg = ffor (current sz) $ \(w,h) -> [V.charFill V.defAttr c w h]
338+-- | Fill the background with the bottom
339+hRule :: (Reflex t, Monad m) => BoxStyle -> VtyWidget t m ()
340+hRule boxStyle = fill (_boxStyle_s boxStyle)
342+fractionSz :: Double -> Int -> Int
343+fractionSz x h = round (fromIntegral h * x)
346+ :: (Reflex t, MonadHold t m, MonadFix m)
347+ => Behavior t ([Image] -> [Image])
350+modifyImages f (VtyWidget w) = VtyWidget $ flip censor w $ \wo ->
351+ wo { _vtyWidgetOut_images = f <*> (_vtyWidgetOut_images wo) }
353+data BoxStyle = BoxStyle
354+ { _boxStyle_nw :: Char
355+ , _boxStyle_n :: Char
356+ , _boxStyle_ne :: Char
357+ , _boxStyle_e :: Char
358+ , _boxStyle_se :: Char
359+ , _boxStyle_s :: Char
360+ , _boxStyle_sw :: Char
361+ , _boxStyle_w :: Char
319−-- | A class for things that can dynamically gain and lose focus
364+instance Default BoxStyle where
320−class (Reflex t, Monad m) => HasFocusReader t m | m -> t where
365+ def = singleBoxStyle
321− focus :: m (Dynamic t Bool)
322− default focus :: (f m' ~ m, Monad m', MonadTrans f, HasFocusReader t m') => m (Dynamic t Bool)
324− localFocus :: (Dynamic t Bool -> Dynamic t Bool) -> m a -> m a
325− default localFocus :: (f m' ~ m, Monad m', MFunctor f, HasFocusReader t m') => (Dynamic t Bool -> Dynamic t Bool) -> m a -> m a
326− localFocus f = hoist (localFocus f)
328−instance HasFocusReader t m => HasFocusReader t (ReaderT x m)
329−instance HasFocusReader t m => HasFocusReader t (BehaviorWriterT t x m)
330−instance HasFocusReader t m => HasFocusReader t (DynamicWriterT t x m)
331−instance HasFocusReader t m => HasFocusReader t (EventWriterT t x m)
332−instance HasFocusReader t m => HasFocusReader t (NodeIdT m)
334−-- | A widget that has access to information about whether it is focused
335−newtype FocusReader t m a = FocusReader
336− { unFocusReader :: ReaderT (Dynamic t Bool) m a }
348−instance (Monad m, Reflex t) => HasFocusReader t (FocusReader t m) where
349− focus = FocusReader ask
350− localFocus f = FocusReader . local f . unFocusReader
352−deriving instance MonadReflexCreateTrigger t m => MonadReflexCreateTrigger t (FocusReader t m)
353−deriving instance NotReady t m => NotReady t (FocusReader t m)
354−deriving instance PerformEvent t m => PerformEvent t (FocusReader t m)
355−deriving instance PostBuild t m => PostBuild t (FocusReader t m)
356−deriving instance TriggerEvent t m => TriggerEvent t (FocusReader t m)
357−instance HasImageWriter t m => HasImageWriter t (FocusReader t m)
359−instance (Adjustable t m, MonadFix m, MonadHold t m) => Adjustable t (FocusReader t m) where
360− runWithReplace (FocusReader a) e = FocusReader $ runWithReplace a $ fmap unFocusReader e
361− traverseIntMapWithKeyWithAdjust f m e = FocusReader $ traverseIntMapWithKeyWithAdjust (\k v -> unFocusReader $ f k v) m e
362− traverseDMapWithKeyWithAdjust f m e = FocusReader $ traverseDMapWithKeyWithAdjust (\k v -> unFocusReader $ f k v) m e
363− traverseDMapWithKeyWithAdjustWithMove f m e = FocusReader $ traverseDMapWithKeyWithAdjustWithMove (\k v -> unFocusReader $ f k v) m e
365−instance MonadTrans (FocusReader t) where
366− lift = FocusReader . lift
368−instance MFunctor (FocusReader t) where
369− hoist f = FocusReader . hoist f . unFocusReader
371−instance MonadNodeId m => MonadNodeId (FocusReader t m)
373−-- | Run a 'FocusReader' action with the given focus value
375− :: (Reflex t, Monad m)
377− -> FocusReader t m a
379−runFocusReader b = flip runReaderT b . unFocusReader
381−-- * "Image" output
367+hyphenBoxStyle :: BoxStyle
368+hyphenBoxStyle = BoxStyle '-' '-' '-' '|' '-' '-' '-' '|'
383−-- | A class for widgets that can produce images to draw to the display
370+singleBoxStyle :: BoxStyle
384−class (Reflex t, Monad m) => HasImageWriter t m | m -> t where
371+singleBoxStyle = BoxStyle '┌' '─' '┐' '│' '┘' '─' '└' '│'
385− -- | Send images upstream for rendering
386− tellImages :: Behavior t [Image] -> m ()
387− default tellImages :: (f m' ~ m, Monad m', MonadTrans f, HasImageWriter t m') => Behavior t [Image] -> m ()
388− tellImages = lift . tellImages
389− -- | Apply a transformation to the images produced by the child actions
390− mapImages :: (Behavior t [Image] -> Behavior t [Image]) -> m a -> m a
391− default mapImages :: (f m' ~ m, Monad m', MFunctor f, HasImageWriter t m') => (Behavior t [Image] -> Behavior t [Image]) -> m a -> m a
392− mapImages f = hoist (mapImages f)
394−-- | A widget that can produce images to draw onto the display
395−newtype ImageWriter t m a = ImageWriter
396− { unImageWriter :: BehaviorWriterT t [Image] m a }
405− , MonadReflexCreateTrigger t
413−instance MonadTrans (ImageWriter t) where
414− lift = ImageWriter . lift
416−instance MFunctor (ImageWriter t) where
417− hoist f = ImageWriter . (hoist f) . unImageWriter
419−instance (Adjustable t m, MonadFix m, MonadHold t m) => Adjustable t (ImageWriter t m) where
420− runWithReplace (ImageWriter a) e = ImageWriter $ runWithReplace a $ fmap unImageWriter e
421− traverseIntMapWithKeyWithAdjust f m e = ImageWriter $ traverseIntMapWithKeyWithAdjust (\k v -> unImageWriter $ f k v) m e
422− traverseDMapWithKeyWithAdjust f m e = ImageWriter $ traverseDMapWithKeyWithAdjust (\k v -> unImageWriter $ f k v) m e
423− traverseDMapWithKeyWithAdjustWithMove f m e = ImageWriter $ traverseDMapWithKeyWithAdjustWithMove (\k v -> unImageWriter $ f k v) m e
425−instance HasImageWriter t m => HasImageWriter t (ReaderT x m)
426−instance HasImageWriter t m => HasImageWriter t (BehaviorWriterT t x m)
427−instance HasImageWriter t m => HasImageWriter t (DynamicWriterT t x m)
428−instance HasImageWriter t m => HasImageWriter t (EventWriterT t x m)
429−instance HasImageWriter t m => HasImageWriter t (NodeIdT m)
431−instance (Monad m, Reflex t) => HasImageWriter t (ImageWriter t m) where
432− tellImages = ImageWriter . tellBehavior
433− mapImages f (ImageWriter x) = ImageWriter $ do
434− (a, images) <- lift $ runBehaviorWriterT x
435− tellBehavior $ f images
438−instance HasDisplayRegion t m => HasDisplayRegion t (ImageWriter t m)
439−instance HasFocusReader t m => HasFocusReader t (ImageWriter t m)
441−-- | Run a widget that can produce images
443− :: (Reflex t, Monad m)
444− => ImageWriter t m a
445− -> m (a, Behavior t [Image])
446−runImageWriter = runBehaviorWriterT . unImageWriter
450−-- | A class for things that can be visually styled
451−class (Reflex t, Monad m) => HasTheme t m | m -> t where
452− theme :: m (Behavior t V.Attr)
453− default theme :: (f m' ~ m, Monad m', MonadTrans f, HasTheme t m') => m (Behavior t V.Attr)
455− localTheme :: (Behavior t V.Attr -> Behavior t V.Attr) -> m a -> m a
456− default localTheme :: (f m' ~ m, Monad m', MFunctor f, HasTheme t m') => (Behavior t V.Attr -> Behavior t V.Attr) -> m a -> m a
457− localTheme f = hoist (localTheme f)
459−instance HasTheme t m => HasTheme t (ReaderT x m)
460−instance HasTheme t m => HasTheme t (BehaviorWriterT t x m)
461−instance HasTheme t m => HasTheme t (DynamicWriterT t x m)
462−instance HasTheme t m => HasTheme t (EventWriterT t x m)
463−instance HasTheme t m => HasTheme t (NodeIdT m)
464−instance HasTheme t m => HasTheme t (Input t m)
465−instance HasTheme t m => HasTheme t (ImageWriter t m)
466−instance HasTheme t m => HasTheme t (DisplayRegion t m)
467−instance HasTheme t m => HasTheme t (FocusReader t m)
469−-- | A widget that has access to theme information
470−newtype ThemeReader t m a = ThemeReader
471− { unThemeReader :: ReaderT (Behavior t V.Attr) m a }
483−instance (Monad m, Reflex t) => HasTheme t (ThemeReader t m) where
484− theme = ThemeReader ask
485− localTheme f = ThemeReader . local f . unThemeReader
487−deriving instance MonadReflexCreateTrigger t m => MonadReflexCreateTrigger t (ThemeReader t m)
488−deriving instance NotReady t m => NotReady t (ThemeReader t m)
489−deriving instance PerformEvent t m => PerformEvent t (ThemeReader t m)
490−deriving instance PostBuild t m => PostBuild t (ThemeReader t m)
491−deriving instance TriggerEvent t m => TriggerEvent t (ThemeReader t m)
492−instance HasImageWriter t m => HasImageWriter t (ThemeReader t m)
494−instance (Adjustable t m, MonadFix m, MonadHold t m) => Adjustable t (ThemeReader t m) where
495− runWithReplace (ThemeReader a) e = ThemeReader $ runWithReplace a $ fmap unThemeReader e
496− traverseIntMapWithKeyWithAdjust f m e = ThemeReader $ traverseIntMapWithKeyWithAdjust (\k v -> unThemeReader $ f k v) m e
497− traverseDMapWithKeyWithAdjust f m e = ThemeReader $ traverseDMapWithKeyWithAdjust (\k v -> unThemeReader $ f k v) m e
498− traverseDMapWithKeyWithAdjustWithMove f m e = ThemeReader $ traverseDMapWithKeyWithAdjustWithMove (\k v -> unThemeReader $ f k v) m e
500−instance MonadTrans (ThemeReader t) where
501− lift = ThemeReader . lift
503−instance MFunctor (ThemeReader t) where
504− hoist f = ThemeReader . hoist f . unThemeReader
506−instance MonadNodeId m => MonadNodeId (ThemeReader t m)
508−-- | Run a 'ThemeReader' action with the given focus value
510− :: (Reflex t, Monad m)
511− => Behavior t V.Attr
512− -> ThemeReader t m a
514−runThemeReader b = flip runReaderT b . unThemeReader
373+thickBoxStyle :: BoxStyle
374+thickBoxStyle = BoxStyle '┏' '━' '┓' '┃' '┛' '━' '┗' '┃'
517−-- ** Manipulating images
376+doubleBoxStyle :: BoxStyle
377+doubleBoxStyle = BoxStyle '╔' '═' '╗' '║' '╝' '═' '╚' '║'
519−-- | Translates and crops an 'Image' so that it is contained by
379+roundedBoxStyle :: BoxStyle
520−-- the given 'Region'.
380+roundedBoxStyle = BoxStyle '╭' '─' '╮' '│' '╯' '─' '╰' '│'
382+box :: (Monad m, Reflex t)
388+ let boxReg = ffor (current sz) $ \(w,h) -> Region 0 0 w h
389+ innerReg = ffor sz $ \(w,h) -> Region 1 1 (w - 2) (h - 2)
390+ tellImages (fmap boxImages boxReg)
391+ tellImages (fmap (\r -> [regionBlankImage r]) (current innerReg))
392+ pane innerReg (pure True) child
522− :: Region
394+ boxImages :: Region -> [Image]
523− -> Image
395+ boxImages (Region left top width height) =
524− -> Image
396+ let right = left + width - 1
397+ bottom = top + height - 1
399+ [ withinImage (Region (left + 1) top (width - 2) 1) $
400+ V.charFill V.defAttr (_boxStyle_n style) (width - 2) 1
401+ , withinImage (Region right (top + 1) 1 (height - 2)) $
402+ V.charFill V.defAttr (_boxStyle_e style) 1 (height - 2)
403+ , withinImage (Region (left + 1) bottom (width - 2) 1) $
404+ V.charFill V.defAttr (_boxStyle_s style) (width - 2) 1
405+ , withinImage (Region left (top + 1) 1 (height - 2)) $
406+ V.charFill V.defAttr (_boxStyle_w style) 1 (height - 2)
409+ [ withinImage (Region left top 1 1) $
410+ V.char V.defAttr (_boxStyle_nw style)
411+ , withinImage (Region right top 1 1) $
412+ V.char V.defAttr (_boxStyle_ne style)
413+ , withinImage (Region right bottom 1 1) $
414+ V.char V.defAttr (_boxStyle_se style)
415+ , withinImage (Region left bottom 1 1) $
416+ V.char V.defAttr (_boxStyle_sw style)
418+ in sides ++ if width > 1 && height > 1 then corners else []
420+string :: (Reflex t, Monad m) => Behavior t String -> VtyWidget t m ()
423+ let img = (\w s -> [wrapString w V.defAttr s]) <$> current dw <*> msg
426+regionBlankImage :: Region -> Image
427+regionBlankImage r@(Region _ _ width height) =
428+ withinImage r $ wrapString width V.defAttr $ replicate (width * height) ' '
430+withinImage :: Region -> Image -> Image
525withinImage (Region left top width height)
431withinImage (Region left top width height)
526 | width < 0 || height < 0 = withinImage (Region left top 0 0)
432 | width < 0 || height < 0 = withinImage (Region left top 0 0)
527 | otherwise = V.translate left top . V.crop width height
433 | otherwise = V.translate left top . V.crop width height
529−-- | Crop a behavior of images to a behavior of regions. See 'withinImage'.
435+wrapString :: Int -> Attr -> String -> Image
530−imagesInRegion
436+wrapString maxWidth attrs = V.vertCat
531− :: Reflex t
437+ . concatMap (fmap (V.string attrs) . fmap (take maxWidth) . takeWhile (not . null) . iterate (drop maxWidth))
532− => Behavior t Region
438+ . lines
533− -> Behavior t [Image]
439+
534− -> Behavior t [Image]
440+wrapInputState
535−imagesInRegion reg = liftA2 (\r is -> map (withinImage r) is) reg
441+ :: Int -- ^ Maximum line length
536−
442+ -> Attr -- ^ Normal string attributes
537−-- * Running sub-widgets
443+ -> Attr -- ^ Cursor character attributes
538−
444+ -> InputState -- ^ The input to render
539−-- | Low-level widget combinator that runs a child widget within
445+ -> Image
540−-- a given region and context. This widget filters and modifies the input
446+wrapInputState maxWidth attrs cursorAttrs (InputState before after) =
541−-- that the child widget receives such that:
447+ let -- Break up the InputState into:
542−-- * unfocused widgets receive no key events
448+ -- * A top section of lines before the line containing the cursor
543−-- * mouse inputs outside the region are ignored
449+ -- * A part of the line containing the cursor that comes immediately before the cursor
544−-- * mouse inputs inside the region have their coordinates translated such
450+ -- * The cursor character (i.e., the character the cursor is on top of)
545−-- that (0,0) is the top-left corner of the region
451+ -- * The remainder of the line containing the cursor
546−pane
452+ -- * The bottom section of lines after the line containing the cursor
547− :: (Reflex t, Monad m, HasInput t m, HasImageWriter t m, HasDisplayRegion t m, HasFocusReader t m)
453+ (top, midBefore, cursorChar, midAfter, bottom) = case (initLast before', headTail after') of
548− => Dynamic t Region
454+ (Nothing, Nothing) -> ([], "", ' ', "", [])
549− -> Dynamic t Bool -- ^ Whether the widget should be focused when the parent is.
455+ (Just (top', mid), Nothing) -> (top', mid, ' ', "", [])
550− -> m a
456+ (Nothing, Just (mid, bottom')) -> case T.uncons mid of
551− -> m a
457+ Nothing -> ([], "", ' ', "", bottom')
552−pane dr foc child = localRegion (const dr) $
458+ Just (c, rest) -> ([], "", c, rest, bottom')
553− mapImages (imagesInRegion $ current dr) $
459+ (Just (top', midB), Just (midA, bottom')) -> case T.uncons midA of
554− localFocus (const foc) $
460+ Nothing -> (top', midB, ' ', "", bottom')
555− inputInFocusedRegion >>= \e -> localInput (const e) child
461+ Just (c, rest) -> (top', midB, c, rest, bottom')
556−
462+ (midBeforeTop, midBefore') = fromMaybe ([], "") $ initLast $ wrap [midBefore]
557−-- * Misc
463+ (midAfter', midAfterBottom) =
558−
464+ let offset = if T.length midBefore' == maxWidth then 1 else T.length midBefore' + 1
559−-- | A widget that draws nothing
465+ in case wrapWithOffset offset midAfter of
560−blank :: Monad m => m ()
466+ [] -> ("", [])
468+ cursor = V.char cursorAttrs cursorChar
469+ in V.vertCat $ mconcat
470+ [ vstring <$> wrap top
471+ , vstring <$> midBeforeTop
472+ , if T.length midBefore' == maxWidth
474+ [ vstring midBefore'
482+ [ vstring midBefore'
487+ , vstring <$> midAfterBottom
488+ , vstring <$> bottom
491+ before' = T.split (=='\n') before
492+ after' = T.split (=='\n') after
493+ vstring = V.string attrs . T.unpack
494+ wrapWithOffset :: Int -> Text -> [Text]
495+ wrapWithOffset n xs =
496+ let (firstLine, rest) = T.splitAt (maxWidth - n) xs
497+ in firstLine : (fmap (T.take maxWidth) . takeWhile (not . T.null) . iterate (T.drop maxWidth) $ rest)
498+ wrap :: [Text] -> [Text]
499+ wrap = concatMap (wrapWithOffset 0)
500+ headTail :: [a] -> Maybe (a, [a])
503+ x:xs -> Just (x, xs)
504+ initLast :: [a] -> Maybe ([a], a)
507+ (x:xs) -> case initLast xs of
508+ Nothing -> Just ([], x)
509+ Just (ys, y) -> Just (x:ys, y)
511+data InputState = InputState
512+ { _inputState_beforeCursor :: Text
513+ , _inputState_afterCursor :: Text
516+inputValue :: InputState -> Text
517+inputValue (InputState a b) = a <> b
519+updateInputState :: V.Event -> InputState -> InputState
520+updateInputState k i@(InputState before after) = case k of
521+ -- Regular characters
522+ V.EvKey (V.KChar k) [] -> InputState (T.snoc before k) after
524+ V.EvKey V.KBS [] -> InputState (if T.null before then T.empty else T.init before) after
525+ V.EvKey V.KDel [] -> case T.uncons after of
527+ Just (_, a) -> InputState before a
529+ V.EvKey (V.KChar 'u') [V.MCtrl] -> InputState mempty mempty
530+ V.EvKey (V.KChar 'w') [V.MCtrl] -> InputState (T.dropWhileEnd (not . isSpace) $ T.dropWhileEnd isSpace $ before) after
532+ V.EvKey V.KRight [] -> case T.uncons after of
534+ Just (a, as) -> InputState (T.snoc before a) as
535+ V.EvKey V.KLeft [] -> case T.unsnoc before of
537+ Just (bs, b) -> InputState bs (T.cons b after)
540+data TextInputConfig t = TextInputConfig
541+ { _textInputConfig_modifyInputState :: Event t (InputState -> InputState)
544+instance Reflex t => Default (TextInputConfig t) where
545+ def = TextInputConfig never
547+textInput :: (Reflex t, MonadHold t m, MonadFix m) => TextInputConfig t -> VtyWidget t m (Dynamic t Text)
550+ v <- foldDyn ($) (InputState mempty mempty) $ mergeWith (.)
551+ [ updateInputState <$> i
552+ , _textInputConfig_modifyInputState cfg
555+ let img = (\w s -> [wrapInputState w V.defAttr (V.withStyle V.defAttr V.reverseVideo) s]) -- TODO cursor ought to blink
561−blank = return ()
559+ return $ inputValue <$> v
561+multilineTextInput :: (Reflex t, MonadHold t m, MonadFix m) => TextInputConfig t -> VtyWidget t m (Dynamic t Text)
562+multilineTextInput cfg = do
564+ textInput $ TextInputConfig $ mergeWith (.)
565+ [ fforMaybe i $ \case
566+ V.EvKey V.KEnter [] -> Just $ \(InputState before after) -> InputState (T.snoc before '\n') after
568+ , _textInputConfig_modifyInputState cfg