@@ -2,41 +2,156 @@
22Module: Reflex.Vty.Widget
33Description: Basic set of widgets and building blocks for reflex-vty applications
44-}
5−{-# Language UndecidableInstances #-}
6−
7−module Reflex.Vty.Widget where
5+{-# LANGUAGE DefaultSignatures #-}
6+{-# LANGUAGE DeriveFunctor #-}
7+{-# LANGUAGE FlexibleContexts #-}
8+{-# LANGUAGE FlexibleInstances #-}
9+{-# LANGUAGE FunctionalDependencies #-}
10+{-# LANGUAGE GeneralizedNewtypeDeriving #-}
11+{-# LANGUAGE LambdaCase #-}
12+{-# LANGUAGE RankNTypes #-}
13+{-# LANGUAGE RecursiveDo #-}
14+{-# LANGUAGE ScopedTypeVariables #-}
15+{-# LANGUAGE StandaloneDeriving #-}
16+{-# LANGUAGE TupleSections #-}
17+{-# LANGUAGE TypeFamilies #-}
18+{-# LANGUAGE UndecidableInstances #-}
19+
20+module Reflex.Vty.Widget
21+ ( VtyWidgetCtx(..)
22+ , VtyWidget(..)
23+ , VtyWidgetOut(..)
24+ , ImageWriter(..)
25+ , runVtyWidget
26+ , mainWidget
27+ , mainWidgetWithHandle
28+ , HasDisplaySize(..)
29+ , HasFocus(..)
30+ , HasVtyInput(..)
31+ , DynRegion(..)
32+ , currentRegion
33+ , Region(..)
34+ , regionSize
35+ , regionBlankImage
36+ , Drag(..)
37+ , drag
38+ , MouseDown(..)
39+ , MouseUp(..)
40+ , mouseDown
41+ , mouseUp
42+ , pane
43+ , splitV
44+ , splitVDrag
45+ , box
46+ , boxStatic
47+ , RichTextConfig(..)
48+ , richText
49+ , text
50+ , display
51+ , BoxStyle(..)
52+ , hyphenBoxStyle
53+ , singleBoxStyle
54+ , roundedBoxStyle
55+ , thickBoxStyle
56+ , doubleBoxStyle
57+ , fill
58+ , hRule
59+ , KeyCombo
60+ , key
61+ , keys
62+ , keyCombo
63+ , keyCombos
64+ , blank
65+ ) where
866
967import Control.Applicative (liftA2)
1068import Control.Monad.Fix (MonadFix)
11−import Control.Monad.IO.Class (MonadIO)
12−import Control.Monad.Morph
13−import Control.Monad.NodeId
14−import Control.Monad.Reader (ReaderT, ask, local, runReaderT)
15−import Control.Monad.Ref
16−import Control.Monad.Trans (MonadTrans, lift)
69+import Control.Monad.Reader
70+import Control.Monad.Trans (lift)
71+import Data.Default (Default(..))
1772import Data.Set (Set)
1873import qualified Data.Set as Set
74+import Data.Text (Text)
75+import qualified Data.Text as T
76+import qualified Data.Text.Zipper as TZ
1977import Graphics.Vty (Image)
2078import qualified Graphics.Vty as V
2179import Reflex
2280import Reflex.Class ()
2381import Reflex.Host.Class (MonadReflexCreateTrigger)
82+
2483import Reflex.Vty.Host
2584
26−-- * Running a vty application
85+import Control.Monad.NodeId
86+
87+-- | The context within which a 'VtyWidget' runs
88+data VtyWidgetCtx t = VtyWidgetCtx
89+ { _vtyWidgetCtx_width :: Dynamic t Int
90+ -- ^ The width of the region allocated to the widget.
91+ , _vtyWidgetCtx_height :: Dynamic t Int
92+ -- ^ The height of the region allocated to the widget.
93+ , _vtyWidgetCtx_focus :: Dynamic t Bool
94+ -- ^ Whether the widget should behave as if it has focus for keyboard input.
95+ , _vtyWidgetCtx_input :: Event t VtyEvent
96+ -- ^ User input events that the widget's parent chooses to share. These will generally
97+ -- be filtered for relevance:
98+ -- * Keyboard inputs are restricted to focused widgets
99+ -- * Mouse inputs are restricted to the region in which the widget resides and are
100+ -- translated into its internal coordinates.
101+ }
102+
103+-- | The output of a 'VtyWidget'
104+data VtyWidgetOut t = VtyWidgetOut
105+ { _vtyWidgetOut_shutdown :: Event t ()
106+ }
27107
28−-- | Sets up the top-level context for a vty widget and runs it with that context
108+instance (Adjustable t m, MonadHold t m, Reflex t) => Adjustable t (VtyWidget t m) where
109+ runWithReplace a0 a' = VtyWidget $ runWithReplace (unVtyWidget a0) $ fmap unVtyWidget a'
110+ traverseIntMapWithKeyWithAdjust f dm0 dm' = VtyWidget $
111+ traverseIntMapWithKeyWithAdjust (\k v -> unVtyWidget (f k v)) dm0 dm'
112+ traverseDMapWithKeyWithAdjust f dm0 dm' = VtyWidget $ do
113+ traverseDMapWithKeyWithAdjust (\k v -> unVtyWidget (f k v)) dm0 dm'
114+ traverseDMapWithKeyWithAdjustWithMove f dm0 dm' = VtyWidget $ do
115+ traverseDMapWithKeyWithAdjustWithMove (\k v -> unVtyWidget (f k v)) dm0 dm'
116+
117+-- | A widget that can read its context and produce image output
118+newtype VtyWidget t m a = VtyWidget
119+ { unVtyWidget :: BehaviorWriterT t [Image] (ReaderT (VtyWidgetCtx t) m) a
120+ } deriving
121+ ( Functor
122+ , Applicative
123+ , Monad
124+ , MonadSample t
125+ , MonadHold t
126+ , MonadFix
127+ , NotReady t
128+ , ImageWriter t
129+ , PostBuild t
130+ , TriggerEvent t
131+ , MonadReflexCreateTrigger t
132+ , MonadIO
133+ )
134+
135+deriving instance PerformEvent t m => PerformEvent t (VtyWidget t m)
136+instance MonadTrans (VtyWidget t) where
137+ lift f = VtyWidget $ lift $ lift f
138+
139+instance MonadNodeId m => MonadNodeId (VtyWidget t m) where
140+ getNextNodeId = VtyWidget $ do
141+ lift $ lift $ getNextNodeId
142+
143+-- | Runs a 'VtyWidget' with a given context
144+runVtyWidget
145+ :: (Reflex t, MonadNodeId m)
146+ => VtyWidgetCtx t
147+ -> VtyWidget t m a
148+ -> m (a, Behavior t [Image])
149+runVtyWidget ctx w = runReaderT (runBehaviorWriterT (unVtyWidget w)) ctx
150+
151+-- | Sets up the top-level context for a 'VtyWidget' and runs it with that context
29152mainWidgetWithHandle
30153 :: V.Vty
31− -> (forall t m.
32− ( MonadVtyApp t m
33− , HasImageWriter t m
34− , MonadNodeId m
35− , HasDisplayRegion t m
36− , HasFocusReader t m
37− , HasInput t m
38− , HasTheme t m
39− ) => m (Event t ()))
154+ -> (forall t m. (MonadVtyApp t m, MonadNodeId m) => VtyWidget t m (Event t ()))
40155 -> IO ()
41156mainWidgetWithHandle vty child =
42157 runVtyAppWithHandle vty $ \dr0 inp -> do
@@ -46,178 +161,71 @@ mainWidgetWithHandle vty child =
46161 let inp' = fforMaybe inp $ \case
47162 V.EvResize {} -> Nothing
48163 x -> Just x
49− (shutdown, images) <- runThemeReader (constant V.defAttr) $
50− runFocusReader (pure True) $
51− runDisplayRegion (fmap (\(w, h) -> Region 0 0 w h) size) $
52− runImageWriter $
53− runNodeIdT $
54− runInput inp' $ do
55− tellImages . ffor (current size) $ \(w, h) -> [V.charFill V.defAttr ' ' w h]
56− child
164+ let ctx = VtyWidgetCtx
165+ { _vtyWidgetCtx_width = fmap fst size
166+ , _vtyWidgetCtx_height = fmap snd size
167+ , _vtyWidgetCtx_input = inp'
168+ , _vtyWidgetCtx_focus = constDyn True
169+ }
170+ (shutdown, images) <- runNodeIdT $ runVtyWidget ctx $ do
171+ tellImages . ffor (current size) $ \(w, h) -> [V.charFill V.defAttr ' ' w h]
172+ child
57173 return $ VtyResult
58174 { _vtyResult_picture = fmap (V.picForLayers . reverse) images
59175 , _vtyResult_shutdown = shutdown
60176 }
61177
62−-- | The output of a vty widget
63−data VtyWidgetOut t = VtyWidgetOut
64− { _vtyWidgetOut_shutdown :: Event t ()
65− }
66−
67178-- | Like 'mainWidgetWithHandle', but uses a default vty configuration
68179mainWidget
69− :: (forall t m.
70− ( MonadVtyApp t m
71− , HasImageWriter t m
72− , MonadNodeId m
73− , HasDisplayRegion t m
74− , HasFocusReader t m
75− , HasTheme t m
76− , HasInput t m
77− ) => m (Event t ()))
180+ :: (forall t m. (MonadVtyApp t m, MonadNodeId m) => VtyWidget t m (Event t ()))
78181 -> IO ()
79182mainWidget child = do
80183 vty <- getDefaultVty
81184 mainWidgetWithHandle vty child
82185
83−-- * Input Events
186+-- | A class for things that know their own display size dimensions
187+class (Reflex t, Monad m) => HasDisplaySize t m | m -> t where
188+ -- | Retrieve the display width (columns)
189+ displayWidth :: m (Dynamic t Int)
190+ default displayWidth :: (f m' ~ m, MonadTrans f, HasDisplaySize t m') => m (Dynamic t Int)
191+ displayWidth = lift displayWidth
192+ -- | Retrieve the display height (rows)
193+ displayHeight :: m (Dynamic t Int)
194+ default displayHeight :: (f m' ~ m, MonadTrans f, HasDisplaySize t m') => m (Dynamic t Int)
195+ displayHeight = lift displayHeight
196+
197+instance (Reflex t, Monad m) => HasDisplaySize t (VtyWidget t m) where
198+ displayWidth = VtyWidget . lift $ asks _vtyWidgetCtx_width
199+ displayHeight = VtyWidget . lift $ asks _vtyWidgetCtx_height
200+
201+instance HasDisplaySize t m => HasDisplaySize t (ReaderT x m)
202+instance HasDisplaySize t m => HasDisplaySize t (BehaviorWriterT t x m)
203+instance HasDisplaySize t m => HasDisplaySize t (DynamicWriterT t x m)
204+instance HasDisplaySize t m => HasDisplaySize t (EventWriterT t x m)
205+
206+instance HasDisplaySize t m => HasDisplaySize t (NodeIdT m)
84207
85208-- | A class for things that can receive vty events as input
86−class HasInput t m | m -> t where
209+class HasVtyInput t m | m -> t where
87210 input :: m (Event t VtyEvent)
88− default input :: (f m' ~ m, Monad m', MonadTrans f, HasInput t m') => m (Event t VtyEvent)
89− input = lift input
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)
95−
96−instance (Reflex t, Monad m) => HasInput t (Input t m) where
97− input = Input ask
98− localInput f (Input m) = Input $ local f m
99−
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
103− } deriving
104− ( Functor
105− , Applicative
106− , Monad
107− , MonadSample t
108− , MonadHold t
109− , MonadFix
110− , MonadIO
111− , MonadRef
112− )
113211
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'
122−
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)
131−
132−instance MonadTrans (Input t) where
133− lift f = Input $ lift f
134−
135−instance MFunctor (Input t) where
136− hoist f = Input . hoist f . unInput
137−
138−instance MonadNodeId m => MonadNodeId (Input t m)
139−
140−-- | Runs an 'Input' with a given context
141−runInput
142− :: Reflex t
143− => Event t VtyEvent
144− -> Input t m a
145− -> m a
146−runInput e w = runReaderT (unInput w) e
147−
148−-- ** Filtering input
212+instance (Reflex t, Monad m) => HasVtyInput t (VtyWidget t m) where
213+ input = VtyWidget . lift $ asks _vtyWidgetCtx_input
149214
150−-- | Type synonym for a key and modifier combination
151−type KeyCombo = (V.Key, [V.Modifier])
152−
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 . (,[])
156−
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 (,[])
160−
161−-- | Emit an event that fires whenever the provided key combination occurs
162−keyCombo
163− :: (Reflex t, Monad m, HasInput t m)
164− => KeyCombo
165− -> m (Event t KeyCombo)
166−keyCombo = keyCombos . Set.singleton
215+-- | A class for things that can dynamically gain and lose focus
216+class HasFocus t m | m -> t where
217+ focus :: m (Dynamic t Bool)
167218
168−-- | Emit an event that fires whenever any of the provided key combinations occur
169−keyCombos
170− :: (Reflex t, Monad m, HasInput t m)
171− => Set KeyCombo
172− -> m (Event t KeyCombo)
173−keyCombos ks = do
174− i <- input
175− return $ fforMaybe i $ \case
176− V.EvKey k m -> if Set.member (k, m) ks
177− then Just (k, m)
178− else Nothing
179− _ -> Nothing
219+instance (Reflex t, Monad m) => HasFocus t (VtyWidget t m) where
220+ focus = VtyWidget . lift $ asks _vtyWidgetCtx_focus
180221
181−-- | Filter the keyboard input that a child widget may receive
182−filterKeys :: (Reflex t, HasInput t m) => (KeyCombo -> Bool) -> m a -> m a
183−filterKeys f x = localInput (ffilter (\case
184− V.EvKey k mods -> f (k, mods)
185− _ -> True)) x
186−
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.
189−--
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
195− _ -> Just e
196− where
197− mouse con x y
198− | or [ x < l
199− , y < t
200− , x >= l + w
201− , y >= t + h ] = Nothing
202− | otherwise =
203− Just (con (x - l) (y - t))
204−
205−-- | Filter mouse input outside the current display region and
206−-- all input if the region is not focused
207−inputInFocusedRegion
208− :: (HasDisplayRegion t m, HasFocusReader t m, HasInput t m)
209− => m (Event t VtyEvent)
210−inputInFocusedRegion = do
211− inp <- input
212− reg <- current <$> askRegion
213− foc <- current <$> focus
214− pure $ fmapMaybe id $ attachWith filterInput ((,) <$> reg <*> foc) inp
215− where
216− filterInput (r, f) = \case
217− V.EvKey {} | not f -> Nothing
218− x -> mouseInRegion r x
222+-- | A class for widgets that can produce images to draw to the display
223+class (Reflex t, Monad m) => ImageWriter t m | m -> t where
224+ -- | Send images upstream for rendering
225+ tellImages :: Behavior t [Image] -> m ()
219226
220−-- * Getting and setting the display region
227+instance (Monad m, Reflex t) => ImageWriter t (BehaviorWriterT t [Image] m) where
228+ tellImages = tellBehavior
221229
222230-- | A chunk of the display area
223231data Region = Region
@@ -228,293 +236,26 @@ data Region = Region
228236 }
229237 deriving (Show, Read, Eq, Ord)
230238
231−-- | A region that occupies no space.
232−nilRegion :: Region
233−nilRegion = Region 0 0 0 0
239+-- | A dynamic chunk of the display area
240+data DynRegion t = DynRegion
241+ { _dynRegion_left :: Dynamic t Int
242+ , _dynRegion_top :: Dynamic t Int
243+ , _dynRegion_width :: Dynamic t Int
244+ , _dynRegion_height :: Dynamic t Int
245+ }
234246
235247-- | The width and height of a 'Region'
236248regionSize :: Region -> (Int, Int)
237249regionSize (Region _ _ w h) = (w, h)
238250
239251-- | Produces an 'Image' that fills a region with space characters
240−regionBlankImage :: V.Attr -> Region -> Image
241−regionBlankImage attr r@(Region _ _ width height) =
242− withinImage r $ V.charFill attr ' ' width height
243−
244−-- | A class for things that know their own display size dimensions
245−class (Reflex t, Monad m) => HasDisplayRegion t m | m -> t where
246− -- | Retrieve the display region
247− askRegion :: m (Dynamic t Region)
248− default askRegion :: (f m' ~ m, MonadTrans f, HasDisplayRegion t m') => m (Dynamic t Region)
249− askRegion = lift askRegion
250− -- | Run an action in a local region, by applying a transformation to the region
251− localRegion :: (Dynamic t Region -> Dynamic t Region) -> m a -> m a
252− default localRegion :: (f m' ~ m, Monad m', MFunctor f, HasDisplayRegion t m') => (Dynamic t Region -> Dynamic t Region) -> m a -> m a
253− localRegion f = hoist (localRegion f)
254−
255−-- | Retrieve the display width
256−displayWidth :: HasDisplayRegion t m => m (Dynamic t Int)
257−displayWidth = fmap _region_width <$> askRegion
258−
259−-- | Retrieve the display height
260−displayHeight :: HasDisplayRegion t m => m (Dynamic t Int)
261−displayHeight = fmap _region_height <$> askRegion
262−
263−instance HasDisplayRegion t m => HasDisplayRegion t (ReaderT x m)
264−instance HasDisplayRegion t m => HasDisplayRegion t (BehaviorWriterT t x m)
265−instance HasDisplayRegion t m => HasDisplayRegion t (DynamicWriterT t x m)
266−instance HasDisplayRegion t m => HasDisplayRegion t (EventWriterT t x m)
267−instance HasDisplayRegion t m => HasDisplayRegion t (NodeIdT m)
268−
269−-- | A widget that has access to a particular region of the vty display
270−newtype DisplayRegion t m a = DisplayRegion
271− { unDisplayRegion :: ReaderT (Dynamic t Region) m a }
272− deriving
273− ( Functor
274− , Applicative
275− , Monad
276− , MonadFix
277− , MonadHold t
278− , MonadIO
279− , MonadRef
280− , MonadSample t
281− )
282−
283−instance (Monad m, Reflex t) => HasDisplayRegion t (DisplayRegion t m) where
284− askRegion = DisplayRegion ask
285− localRegion f = DisplayRegion . local f . unDisplayRegion
286−
287−deriving instance MonadReflexCreateTrigger t m => MonadReflexCreateTrigger t (DisplayRegion t m)
288−deriving instance NotReady t m => NotReady t (DisplayRegion t m)
289−deriving instance PerformEvent t m => PerformEvent t (DisplayRegion t m)
290−deriving instance PostBuild t m => PostBuild t (DisplayRegion t m)
291−deriving instance TriggerEvent t m => TriggerEvent t (DisplayRegion t m)
292−instance HasImageWriter t m => HasImageWriter t (DisplayRegion t m)
293−instance HasFocusReader t m => HasFocusReader t (DisplayRegion t m)
294−
295−instance (Adjustable t m, MonadFix m, MonadHold t m) => Adjustable t (DisplayRegion t m) where
296− runWithReplace (DisplayRegion a) e = DisplayRegion $ runWithReplace a $ fmap unDisplayRegion e
297− traverseIntMapWithKeyWithAdjust f m e = DisplayRegion $ traverseIntMapWithKeyWithAdjust (\k v -> unDisplayRegion $ f k v) m e
298− traverseDMapWithKeyWithAdjust f m e = DisplayRegion $ traverseDMapWithKeyWithAdjust (\k v -> unDisplayRegion $ f k v) m e
299− traverseDMapWithKeyWithAdjustWithMove f m e = DisplayRegion $ traverseDMapWithKeyWithAdjustWithMove (\k v -> unDisplayRegion $ f k v) m e
300−
301−instance MonadTrans (DisplayRegion t) where
302− lift = DisplayRegion . lift
303−
304−instance MFunctor (DisplayRegion t) where
305− hoist f = DisplayRegion . hoist f . unDisplayRegion
306−
307−instance MonadNodeId m => MonadNodeId (DisplayRegion t m)
308−
309−-- | Run a 'DisplayRegion' action with a given 'Region'
310−runDisplayRegion
311− :: (Reflex t, Monad m)
312− => Dynamic t Region
313− -> DisplayRegion t m a
314− -> m a
315−runDisplayRegion r = flip runReaderT r . unDisplayRegion
316−
317−-- * Getting focus state
318−
319−-- | A class for things that can dynamically gain and lose focus
320−class (Reflex t, Monad m) => HasFocusReader t m | m -> t where
321− focus :: m (Dynamic t Bool)
322− default focus :: (f m' ~ m, Monad m', MonadTrans f, HasFocusReader t m') => m (Dynamic t Bool)
323− focus = lift focus
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)
327−
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)
333−
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 }
337− deriving
338− ( Functor
339− , Applicative
340− , Monad
341− , MonadFix
342− , MonadHold t
343− , MonadIO
344− , MonadRef
345− , MonadSample t
346− )
347−
348−instance (Monad m, Reflex t) => HasFocusReader t (FocusReader t m) where
349− focus = FocusReader ask
350− localFocus f = FocusReader . local f . unFocusReader
351−
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)
252+regionBlankImage :: Region -> Image
253+regionBlankImage r@(Region _ _ width height) =
254+ withinImage r $ V.charFill V.defAttr ' ' width height
358255
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
364−
365−instance MonadTrans (FocusReader t) where
366− lift = FocusReader . lift
367−
368−instance MFunctor (FocusReader t) where
369− hoist f = FocusReader . hoist f . unFocusReader
370−
371−instance MonadNodeId m => MonadNodeId (FocusReader t m)
372−
373−-- | Run a 'FocusReader' action with the given focus value
374−runFocusReader
375− :: (Reflex t, Monad m)
376− => Dynamic t Bool
377− -> FocusReader t m a
378− -> m a
379−runFocusReader b = flip runReaderT b . unFocusReader
380−
381−-- * "Image" output
382−
383−-- | A class for widgets that can produce images to draw to the display
384−class (Reflex t, Monad m) => HasImageWriter t m | m -> t where
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)
393−
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 }
397− deriving
398− ( Functor
399− , Applicative
400− , Monad
401− , MonadFix
402− , MonadHold t
403− , MonadIO
404− , MonadRef
405− , MonadReflexCreateTrigger t
406− , MonadSample t
407− , NotReady t
408− , PerformEvent t
409− , PostBuild t
410− , TriggerEvent t
411− )
412−
413−instance MonadTrans (ImageWriter t) where
414− lift = ImageWriter . lift
415−
416−instance MFunctor (ImageWriter t) where
417− hoist f = ImageWriter . (hoist f) . unImageWriter
418−
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
424−
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)
430−
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
436− pure a
437−
438−instance HasDisplayRegion t m => HasDisplayRegion t (ImageWriter t m)
439−instance HasFocusReader t m => HasFocusReader t (ImageWriter t m)
440−
441−-- | Run a widget that can produce images
442−runImageWriter
443− :: (Reflex t, Monad m)
444− => ImageWriter t m a
445− -> m (a, Behavior t [Image])
446−runImageWriter = runBehaviorWriterT . unImageWriter
447−
448−-- * Theming
449−
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)
454− theme = lift theme
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)
458−
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)
468−
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 }
472− deriving
473− ( Functor
474− , Applicative
475− , Monad
476− , MonadFix
477− , MonadHold t
478− , MonadIO
479− , MonadRef
480− , MonadSample t
481− )
482−
483−instance (Monad m, Reflex t) => HasTheme t (ThemeReader t m) where
484− theme = ThemeReader ask
485− localTheme f = ThemeReader . local f . unThemeReader
486−
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)
493−
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
499−
500−instance MonadTrans (ThemeReader t) where
501− lift = ThemeReader . lift
502−
503−instance MFunctor (ThemeReader t) where
504− hoist f = ThemeReader . hoist f . unThemeReader
505−
506−instance MonadNodeId m => MonadNodeId (ThemeReader t m)
507−
508−-- | Run a 'ThemeReader' action with the given focus value
509−runThemeReader
510− :: (Reflex t, Monad m)
511− => Behavior t V.Attr
512− -> ThemeReader t m a
513− -> m a
514−runThemeReader b = flip runReaderT b . unThemeReader
515−
516−
517−-- ** Manipulating images
256+-- | A behavior of the current display area represented by a 'DynRegion'
257+currentRegion :: Reflex t => DynRegion t -> Behavior t Region
258+currentRegion (DynRegion l t w h) = Region <$> current l <*> current t <*> current w <*> current h
518259
519260-- | Translates and crops an 'Image' so that it is contained by
520261-- the given 'Region'.
@@ -526,17 +267,7 @@ withinImage (Region left top width height)
526267 | width < 0 || height < 0 = withinImage (Region left top 0 0)
527268 | otherwise = V.translate left top . V.crop width height
528269
529−-- | Crop a behavior of images to a behavior of regions. See 'withinImage'.
530−imagesInRegion
531− :: Reflex t
532− => Behavior t Region
533− -> Behavior t [Image]
534− -> Behavior t [Image]
535−imagesInRegion reg = liftA2 (\r is -> map (withinImage r) is) reg
536−
537−-- * Running sub-widgets
538−
539−-- | Low-level widget combinator that runs a child widget within
270+-- | Low-level widget combinator that runs a child 'VtyWidget' within
540271-- a given region and context. This widget filters and modifies the input
541272-- that the child widget receives such that:
542273-- * unfocused widgets receive no key events
@@ -544,18 +275,364 @@ imagesInRegion reg = liftA2 (\r is -> map (withinImage r) is) reg
544275-- * mouse inputs inside the region have their coordinates translated such
545276-- that (0,0) is the top-left corner of the region
546277pane
547− :: (Reflex t, Monad m, HasInput t m, HasImageWriter t m, HasDisplayRegion t m, HasFocusReader t m)
548− => Dynamic t Region
278+ :: (Reflex t, Monad m, MonadNodeId m)
279+ => DynRegion t
549280 -> Dynamic t Bool -- ^ Whether the widget should be focused when the parent is.
550− -> m a
551− -> m a
552−pane dr foc child = localRegion (const dr) $
553− mapImages (imagesInRegion $ current dr) $
554− localFocus (const foc) $
555− inputInFocusedRegion >>= \e -> localInput (const e) child
281+ -> VtyWidget t m a
282+ -> VtyWidget t m a
283+pane dr foc child = VtyWidget $ do
284+ ctx <- lift ask
285+ let reg = currentRegion dr
286+ let ctx' = VtyWidgetCtx
287+ { _vtyWidgetCtx_input = leftmost -- TODO: think about this leftmost more.
288+ [ fmapMaybe id $
289+ attachWith (\(r,f) e -> filterInput r f e)
290+ (liftA2 (,) reg (current foc))
291+ (_vtyWidgetCtx_input ctx)
292+ ]
293+ , _vtyWidgetCtx_focus = liftA2 (&&) (_vtyWidgetCtx_focus ctx) foc
294+ , _vtyWidgetCtx_width = _dynRegion_width dr
295+ , _vtyWidgetCtx_height = _dynRegion_height dr
296+ }
297+ (result, images) <- lift . lift $ runVtyWidget ctx' child
298+ let images' = liftA2 (\r is -> map (withinImage r) is) reg images
299+ tellImages images'
300+ return result
301+ where
302+ filterInput :: Region -> Bool -> VtyEvent -> Maybe VtyEvent
303+ filterInput (Region l t w h) focused e = case e of
304+ V.EvKey _ _ | not focused -> Nothing
305+ V.EvMouseDown x y btn m -> mouse (\u v -> V.EvMouseDown u v btn m) x y
306+ V.EvMouseUp x y btn -> mouse (\u v -> V.EvMouseUp u v btn) x y
307+ _ -> Just e
308+ where
309+ mouse con x y
310+ | or [ x < l
311+ , y < t
312+ , x >= l + w
313+ , y >= t + h ] = Nothing
314+ | otherwise =
315+ Just (con (x - l) (y - t))
316+
317+-- | Information about a drag operation
318+data Drag = Drag
319+ { _drag_from :: (Int, Int) -- ^ Where the drag began
320+ , _drag_to :: (Int, Int) -- ^ Where the mouse currently is
321+ , _drag_button :: V.Button -- ^ Which mouse button is dragging
322+ , _drag_modifiers :: [V.Modifier] -- ^ What modifiers are held
323+ , _drag_end :: Bool -- ^ Whether the drag ended (the mouse button was released)
324+ }
325+ deriving (Eq, Ord, Show)
326+
327+-- | Converts raw vty mouse drag events into an event stream of 'Drag's
328+drag
329+ :: (Reflex t, MonadFix m, MonadHold t m)
330+ => V.Button
331+ -> VtyWidget t m (Event t Drag)
332+drag btn = do
333+ inp <- input
334+ let f :: Maybe Drag -> V.Event -> Maybe Drag
335+ f Nothing = \case
336+ V.EvMouseDown x y btn' mods
337+ | btn == btn' -> Just $ Drag (x,y) (x,y) btn' mods False
338+ | otherwise -> Nothing
339+ _ -> Nothing
340+ f (Just (Drag from _ _ mods end)) = \case
341+ V.EvMouseDown x y btn' mods'
342+ | end -> Just $ Drag (x,y) (x,y) btn' mods' False
343+ | btn == btn' -> Just $ Drag from (x,y) btn mods' False
344+ | otherwise -> Nothing -- Ignore other buttons.
345+ V.EvMouseUp x y (Just btn')
346+ | end -> Nothing
347+ | btn == btn' -> Just $ Drag from (x,y) btn mods True
348+ | otherwise -> Nothing
349+ V.EvMouseUp x y Nothing -- Terminal doesn't specify mouse up button,
350+ -- assume it's the right one.
351+ | end -> Nothing
352+ | otherwise -> Just $ Drag from (x,y) btn mods True
353+ _ -> Nothing
354+ rec let newDrag = attachWithMaybe f (current dragD) inp
355+ dragD <- holdDyn Nothing $ Just <$> newDrag
356+ return (fmapMaybe id $ updated dragD)
357+
358+-- | Mouse down events for a particular mouse button
359+mouseDown
360+ :: (Reflex t, Monad m)
361+ => V.Button
362+ -> VtyWidget t m (Event t MouseDown)
363+mouseDown btn = do
364+ i <- input
365+ return $ fforMaybe i $ \case
366+ V.EvMouseDown x y btn' mods -> if btn == btn'
367+ then Just $ MouseDown btn' (x, y) mods
368+ else Nothing
369+ _ -> Nothing
370+
371+-- | Mouse up events for a particular mouse button
372+mouseUp
373+ :: (Reflex t, Monad m)
374+ => VtyWidget t m (Event t MouseUp)
375+mouseUp = do
376+ i <- input
377+ return $ fforMaybe i $ \case
378+ V.EvMouseUp x y btn' -> Just $ MouseUp btn' (x, y)
379+ _ -> Nothing
556380
557−-- * Misc
381+-- | Information about a mouse down event
382+data MouseDown = MouseDown
383+ { _mouseDown_button :: V.Button
384+ , _mouseDown_coordinates :: (Int, Int)
385+ , _mouseDown_modifiers :: [V.Modifier]
386+ }
387+ deriving (Eq, Ord, Show)
388+
389+-- | Information about a mouse up event
390+data MouseUp = MouseUp
391+ { _mouseUp_button :: Maybe V.Button
392+ , _mouseUp_coordinates :: (Int, Int)
393+ }
394+ deriving (Eq, Ord, Show)
395+
396+-- | Type synonym for a key and modifier combination
397+type KeyCombo = (V.Key, [V.Modifier])
398+
399+-- | Emits an event that fires on a particular key press (without modifiers)
400+key :: (Monad m, Reflex t) => V.Key -> VtyWidget t m (Event t KeyCombo)
401+key = keyCombos . Set.singleton . (,[])
402+
403+-- | Emits an event that fires on particular key presses (without modifiers)
404+keys :: (Monad m, Reflex t) => [V.Key] -> VtyWidget t m (Event t KeyCombo)
405+keys = keyCombos . Set.fromList . fmap (,[])
406+
407+-- | Emit an event that fires whenever the provided key combination occurs
408+keyCombo
409+ :: (Reflex t, Monad m)
410+ => KeyCombo
411+ -> VtyWidget t m (Event t KeyCombo)
412+keyCombo = keyCombos . Set.singleton
413+
414+-- | Emit an event that fires whenever any of the provided key combinations occur
415+keyCombos
416+ :: (Reflex t, Monad m)
417+ => Set KeyCombo
418+ -> VtyWidget t m (Event t KeyCombo)
419+keyCombos ks = do
420+ i <- input
421+ return $ fforMaybe i $ \case
422+ V.EvKey k m -> if Set.member (k, m) ks
423+ then Just (k, m)
424+ else Nothing
425+ _ -> Nothing
426+
427+-- | A plain split of the available space into vertically stacked panes.
428+-- No visual separator is built in here.
429+splitV :: (Reflex t, Monad m, MonadNodeId m)
430+ => Dynamic t (Int -> Int)
431+ -- ^ Function used to determine size of first pane based on available size
432+ -> Dynamic t (Bool, Bool)
433+ -- ^ How to focus the two sub-panes, given that we are focused.
434+ -> VtyWidget t m a
435+ -- ^ Widget for first pane
436+ -> VtyWidget t m b
437+ -- ^ Widget for second pane
438+ -> VtyWidget t m (a,b)
439+splitV sizeFunD focD wA wB = do
440+ dw <- displayWidth
441+ dh <- displayHeight
442+ let regA = DynRegion
443+ { _dynRegion_left = pure 0
444+ , _dynRegion_top = pure 0
445+ , _dynRegion_width = dw
446+ , _dynRegion_height = sizeFunD <*> dh
447+ }
448+ regB = DynRegion
449+ { _dynRegion_left = pure 0
450+ , _dynRegion_top = _dynRegion_height regA
451+ , _dynRegion_width = dw
452+ , _dynRegion_height = liftA2 (-) dh (_dynRegion_height regA)
453+ }
454+ ra <- pane regA (fst <$> focD) wA
455+ rb <- pane regB (snd <$> focD) wB
456+ return (ra,rb)
457+
458+-- | A split of the available space into two parts with a draggable separator.
459+-- Starts with half the space allocated to each, and the first pane has focus.
460+-- Clicking in a pane switches focus.
461+splitVDrag :: (Reflex t, MonadFix m, MonadHold t m, MonadNodeId m)
462+ => VtyWidget t m ()
463+ -> VtyWidget t m a
464+ -> VtyWidget t m b
465+ -> VtyWidget t m (a,b)
466+splitVDrag wS wA wB = do
467+ dh <- displayHeight
468+ dw <- displayWidth
469+ h0 <- sample $ current dh -- TODO
470+ dragE <- drag V.BLeft
471+ let splitter0 = h0 `div` 2
472+ rec splitterCheckpoint <- holdDyn splitter0 $ leftmost [fst <$> ffilter snd dragSplitter, resizeSplitter]
473+ splitterPos <- holdDyn splitter0 $ leftmost [fst <$> dragSplitter, resizeSplitter]
474+ splitterFrac <- holdDyn ((1::Double) / 2) $ ffor (attach (current dh) (fst <$> dragSplitter)) $ \(h, x) ->
475+ fromIntegral x / (max 1 (fromIntegral h))
476+ let dragSplitter = fforMaybe (attach (current splitterCheckpoint) dragE) $
477+ \(splitterY, Drag (_, fromY) (_, toY) _ _ end) ->
478+ if splitterY == fromY then Just (toY, end) else Nothing
479+ regA = DynRegion 0 0 dw splitterPos
480+ regS = DynRegion 0 splitterPos dw 1
481+ regB = DynRegion 0 (splitterPos + 1) dw (dh - splitterPos - 1)
482+ resizeSplitter = ffor (attach (current splitterFrac) (updated dh)) $
483+ \(frac, h) -> round (frac * fromIntegral h)
484+ focA <- holdDyn True $ leftmost
485+ [ True <$ mA
486+ , False <$ mB
487+ ]
488+ (mA, rA) <- pane regA focA $ withMouseDown wA
489+ pane regS (pure False) wS
490+ (mB, rB) <- pane regB (not <$> focA) $ withMouseDown wB
491+ return (rA, rB)
492+ where
493+ withMouseDown x = do
494+ m <- mouseDown V.BLeft
495+ x' <- x
496+ return (m, x')
497+
498+-- | Fill the background with a particular character.
499+fill :: (Reflex t, Monad m) => Char -> VtyWidget t m ()
500+fill c = do
501+ dw <- displayWidth
502+ dh <- displayHeight
503+ let fillImg = current $ liftA2 (\w h -> [V.charFill V.defAttr c w h]) dw dh
504+ tellImages fillImg
505+
506+-- | Fill the background with the bottom
507+hRule :: (Reflex t, Monad m) => BoxStyle -> VtyWidget t m ()
508+hRule boxStyle = fill (_boxStyle_s boxStyle)
509+
510+-- | Defines a set of symbols to use to draw the outlines of boxes
511+-- C.f. https://en.wikipedia.org/wiki/Box-drawing_character
512+data BoxStyle = BoxStyle
513+ { _boxStyle_nw :: Char
514+ , _boxStyle_n :: Char
515+ , _boxStyle_ne :: Char
516+ , _boxStyle_e :: Char
517+ , _boxStyle_se :: Char
518+ , _boxStyle_s :: Char
519+ , _boxStyle_sw :: Char
520+ , _boxStyle_w :: Char
521+ }
522+
523+instance Default BoxStyle where
524+ def = singleBoxStyle
525+
526+-- | A box style that uses hyphens and pipe characters. Doesn't handle
527+-- corners very well.
528+hyphenBoxStyle :: BoxStyle
529+hyphenBoxStyle = BoxStyle '-' '-' '-' '|' '-' '-' '-' '|'
530+
531+-- | A single line box style
532+singleBoxStyle :: BoxStyle
533+singleBoxStyle = BoxStyle '┌' '─' '┐' '│' '┘' '─' '└' '│'
534+
535+-- | A thick single line box style
536+thickBoxStyle :: BoxStyle
537+thickBoxStyle = BoxStyle '┏' '━' '┓' '┃' '┛' '━' '┗' '┃'
538+
539+-- | A double line box style
540+doubleBoxStyle :: BoxStyle
541+doubleBoxStyle = BoxStyle '╔' '═' '╗' '║' '╝' '═' '╚' '║'
542+
543+-- | A single line box style with rounded corners
544+roundedBoxStyle :: BoxStyle
545+roundedBoxStyle = BoxStyle '╭' '─' '╮' '│' '╯' '─' '╰' '│'
546+
547+-- | Draws a box in the provided style and a child widget inside of that box
548+box :: (Monad m, Reflex t, MonadNodeId m)
549+ => Behavior t BoxStyle
550+ -> VtyWidget t m a
551+ -> VtyWidget t m a
552+box boxStyle child = do
553+ dh <- displayHeight
554+ dw <- displayWidth
555+ let boxReg = DynRegion (pure 0) (pure 0) dw dh
556+ innerReg = DynRegion (pure 1) (pure 1) (subtract 2 <$> dw) (subtract 2 <$> dh)
557+ tellImages (boxImages <$> boxStyle <*> currentRegion boxReg)
558+ tellImages (fmap (\r -> [regionBlankImage r]) (currentRegion innerReg))
559+ pane innerReg (pure True) child
560+ where
561+ boxImages :: BoxStyle -> Region -> [Image]
562+ boxImages style (Region left top width height) =
563+ let right = left + width - 1
564+ bottom = top + height - 1
565+ sides =
566+ [ withinImage (Region (left + 1) top (width - 2) 1) $
567+ V.charFill V.defAttr (_boxStyle_n style) (width - 2) 1
568+ , withinImage (Region right (top + 1) 1 (height - 2)) $
569+ V.charFill V.defAttr (_boxStyle_e style) 1 (height - 2)
570+ , withinImage (Region (left + 1) bottom (width - 2) 1) $
571+ V.charFill V.defAttr (_boxStyle_s style) (width - 2) 1
572+ , withinImage (Region left (top + 1) 1 (height - 2)) $
573+ V.charFill V.defAttr (_boxStyle_w style) 1 (height - 2)
574+ ]
575+ corners =
576+ [ withinImage (Region left top 1 1) $
577+ V.char V.defAttr (_boxStyle_nw style)
578+ , withinImage (Region right top 1 1) $
579+ V.char V.defAttr (_boxStyle_ne style)
580+ , withinImage (Region right bottom 1 1) $
581+ V.char V.defAttr (_boxStyle_se style)
582+ , withinImage (Region left bottom 1 1) $
583+ V.char V.defAttr (_boxStyle_sw style)
584+ ]
585+ in sides ++ if width > 1 && height > 1 then corners else []
586+
587+-- | A box whose style is static
588+boxStatic
589+ :: (Reflex t, Monad m, MonadNodeId m)
590+ => BoxStyle
591+ -> VtyWidget t m a
592+ -> VtyWidget t m a
593+boxStatic = box . pure
594+
595+-- | Configuration options for displaying "rich" text
596+data RichTextConfig t = RichTextConfig
597+ { _richTextConfig_attributes :: Behavior t V.Attr
598+ }
599+
600+instance Reflex t => Default (RichTextConfig t) where
601+ def = RichTextConfig $ pure V.defAttr
602+
603+-- | A widget that displays text with custom time-varying attributes
604+richText
605+ :: (Reflex t, Monad m)
606+ => RichTextConfig t
607+ -> Behavior t Text
608+ -> VtyWidget t m ()
609+richText cfg t = do
610+ dw <- displayWidth
611+ let img = (\w a s -> [wrapText w a s])
612+ <$> current dw
613+ <*> _richTextConfig_attributes cfg
614+ <*> t
615+ tellImages img
616+ where
617+ wrapText maxWidth attrs = V.vertCat
618+ . concatMap (fmap (V.string attrs . T.unpack) . TZ.wrapWithOffset maxWidth 0)
619+ . T.split (=='\n')
620+
621+-- | Renders text, wrapped to the container width
622+text
623+ :: (Reflex t, Monad m)
624+ => Behavior t Text
625+ -> VtyWidget t m ()
626+text = richText def
627+
628+-- | Renders any behavior whose value can be converted to
629+-- 'String' as text
630+display
631+ :: (Reflex t, Monad m, Show a)
632+ => Behavior t a
633+ -> VtyWidget t m ()
634+display a = text $ T.pack . show <$> a
558635
559636-- | A widget that draws nothing
560−blank :: Monad m => m ()
637+blank :: Monad m => VtyWidget t m ()
561638blank = return ()