@@ -2,41 +2,161 @@
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+ , Region(..)
32+ , regionSize
33+ , regionBlankImage
34+ , Drag(..)
35+ , drag
36+ , MouseDown(..)
37+ , MouseUp(..)
38+ , mouseDown
39+ , mouseUp
40+ , ScrollDirection(..)
41+ , mouseScroll
42+ , pane
43+ , splitV
44+ , splitH
45+ , splitVDrag
46+ , boxTitle
47+ , box
48+ , boxStatic
49+ , RichTextConfig(..)
50+ , richText
51+ , text
52+ , scrollableText
53+ , display
54+ , BoxStyle(..)
55+ , hyphenBoxStyle
56+ , singleBoxStyle
57+ , roundedBoxStyle
58+ , thickBoxStyle
59+ , doubleBoxStyle
60+ , fill
61+ , hRule
62+ , KeyCombo
63+ , key
64+ , keys
65+ , keyCombo
66+ , keyCombos
67+ , blank
68+ ) where
869
970import Control.Applicative (liftA2)
71+import Control.Monad (join)
1072import Control.Monad.Fix (MonadFix)
1173import 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
74+import Control.Monad.Reader (ReaderT, ask, asks, runReaderT)
1675import Control.Monad.Trans (MonadTrans, lift)
76+import Data.Default (Default(..))
1777import Data.Set (Set)
1878import qualified Data.Set as Set
79+import Data.Text (Text)
80+import qualified Data.Text as T
81+import qualified Data.Text.Zipper as TZ
1982import Graphics.Vty (Image)
2083import qualified Graphics.Vty as V
2184import Reflex
2285import Reflex.Class ()
2386import Reflex.Host.Class (MonadReflexCreateTrigger)
87+
2488import Reflex.Vty.Host
2589
26−-- * Running a vty application
90+import Control.Monad.NodeId
91+
92+-- | The context within which a 'VtyWidget' runs
93+data VtyWidgetCtx t = VtyWidgetCtx
94+ { _vtyWidgetCtx_width :: Dynamic t Int
95+ -- ^ The width of the region allocated to the widget.
96+ , _vtyWidgetCtx_height :: Dynamic t Int
97+ -- ^ The height of the region allocated to the widget.
98+ , _vtyWidgetCtx_focus :: Dynamic t Bool
99+ -- ^ Whether the widget should behave as if it has focus for keyboard input.
100+ , _vtyWidgetCtx_input :: Event t VtyEvent
101+ -- ^ User input events that the widget's parent chooses to share. These will generally
102+ -- be filtered for relevance:
103+ -- * Keyboard inputs are restricted to focused widgets
104+ -- * Mouse inputs are restricted to the region in which the widget resides and are
105+ -- translated into its internal coordinates.
106+ }
107+
108+-- | The output of a 'VtyWidget'
109+data VtyWidgetOut t = VtyWidgetOut
110+ { _vtyWidgetOut_shutdown :: Event t ()
111+ }
112+
113+instance (Adjustable t m, MonadHold t m, Reflex t) => Adjustable t (VtyWidget t m) where
114+ runWithReplace a0 a' = VtyWidget $ runWithReplace (unVtyWidget a0) $ fmap unVtyWidget a'
115+ traverseIntMapWithKeyWithAdjust f dm0 dm' = VtyWidget $
116+ traverseIntMapWithKeyWithAdjust (\k v -> unVtyWidget (f k v)) dm0 dm'
117+ traverseDMapWithKeyWithAdjust f dm0 dm' = VtyWidget $ do
118+ traverseDMapWithKeyWithAdjust (\k v -> unVtyWidget (f k v)) dm0 dm'
119+ traverseDMapWithKeyWithAdjustWithMove f dm0 dm' = VtyWidget $ do
120+ traverseDMapWithKeyWithAdjustWithMove (\k v -> unVtyWidget (f k v)) dm0 dm'
121+
122+-- | A widget that can read its context and produce image output
123+newtype VtyWidget t m a = VtyWidget
124+ { unVtyWidget :: BehaviorWriterT t [Image] (ReaderT (VtyWidgetCtx t) m) a
125+ } deriving
126+ ( Functor
127+ , Applicative
128+ , Monad
129+ , MonadSample t
130+ , MonadHold t
131+ , MonadFix
132+ , NotReady t
133+ , ImageWriter t
134+ , PostBuild t
135+ , TriggerEvent t
136+ , MonadReflexCreateTrigger t
137+ , MonadIO
138+ )
139+
140+deriving instance PerformEvent t m => PerformEvent t (VtyWidget t m)
141+instance MonadTrans (VtyWidget t) where
142+ lift f = VtyWidget $ lift $ lift f
143+
144+instance MonadNodeId m => MonadNodeId (VtyWidget t m) where
145+ getNextNodeId = VtyWidget $ do
146+ lift $ lift getNextNodeId
147+
148+-- | Runs a 'VtyWidget' with a given context
149+runVtyWidget
150+ :: (Reflex t, MonadNodeId m)
151+ => VtyWidgetCtx t
152+ -> VtyWidget t m a
153+ -> m (a, Behavior t [Image])
154+runVtyWidget ctx w = runReaderT (runBehaviorWriterT (unVtyWidget w)) ctx
27155
28−-- | Sets up the top-level context for a vty widget and runs it with that context
156+-- | Sets up the top-level context for a 'VtyWidget' and runs it with that context
29157mainWidgetWithHandle
30158 :: 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 ()))
159+ -> (forall t m. (MonadVtyApp t m, MonadNodeId m) => VtyWidget t m (Event t ()))
40160 -> IO ()
41161mainWidgetWithHandle vty child =
42162 runVtyAppWithHandle vty $ \dr0 inp -> do
@@ -46,178 +166,71 @@ mainWidgetWithHandle vty child =
46166 let inp' = fforMaybe inp $ \case
47167 V.EvResize {} -> Nothing
48168 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
169+ let ctx = VtyWidgetCtx
170+ { _vtyWidgetCtx_width = fmap fst size
171+ , _vtyWidgetCtx_height = fmap snd size
172+ , _vtyWidgetCtx_input = inp'
173+ , _vtyWidgetCtx_focus = constDyn True
174+ }
175+ (shutdown, images) <- runNodeIdT $ runVtyWidget ctx $ do
176+ tellImages . ffor (current size) $ \(w, h) -> [V.charFill V.defAttr ' ' w h]
177+ child
57178 return $ VtyResult
58179 { _vtyResult_picture = fmap (V.picForLayers . reverse) images
59180 , _vtyResult_shutdown = shutdown
60181 }
61182
62−-- | The output of a vty widget
63−data VtyWidgetOut t = VtyWidgetOut
64− { _vtyWidgetOut_shutdown :: Event t ()
65− }
66−
67183-- | Like 'mainWidgetWithHandle', but uses a default vty configuration
68184mainWidget
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 ()))
185+ :: (forall t m. (MonadVtyApp t m, MonadNodeId m) => VtyWidget t m (Event t ()))
78186 -> IO ()
79187mainWidget child = do
80188 vty <- getDefaultVty
81189 mainWidgetWithHandle vty child
82190
83−-- * Input Events
191+-- | A class for things that know their own display size dimensions
192+class (Reflex t, Monad m) => HasDisplaySize t m | m -> t where
193+ -- | Retrieve the display width (columns)
194+ displayWidth :: m (Dynamic t Int)
195+ default displayWidth :: (f m' ~ m, MonadTrans f, HasDisplaySize t m') => m (Dynamic t Int)
196+ displayWidth = lift displayWidth
197+ -- | Retrieve the display height (rows)
198+ displayHeight :: m (Dynamic t Int)
199+ default displayHeight :: (f m' ~ m, MonadTrans f, HasDisplaySize t m') => m (Dynamic t Int)
200+ displayHeight = lift displayHeight
201+
202+instance (Reflex t, Monad m) => HasDisplaySize t (VtyWidget t m) where
203+ displayWidth = VtyWidget . lift $ asks _vtyWidgetCtx_width
204+ displayHeight = VtyWidget . lift $ asks _vtyWidgetCtx_height
205+
206+instance HasDisplaySize t m => HasDisplaySize t (ReaderT x m)
207+instance HasDisplaySize t m => HasDisplaySize t (BehaviorWriterT t x m)
208+instance HasDisplaySize t m => HasDisplaySize t (DynamicWriterT t x m)
209+instance HasDisplaySize t m => HasDisplaySize t (EventWriterT t x m)
210+
211+instance HasDisplaySize t m => HasDisplaySize t (NodeIdT m)
84212
85213-- | A class for things that can receive vty events as input
86−class HasInput t m | m -> t where
214+class HasVtyInput t m | m -> t where
87215 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− )
113216
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
217+instance (Reflex t, Monad m) => HasVtyInput t (VtyWidget t m) where
218+ input = VtyWidget . lift $ asks _vtyWidgetCtx_input
149219
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
220+-- | A class for things that can dynamically gain and lose focus
221+class HasFocus t m | m -> t where
222+ focus :: m (Dynamic t Bool)
167223
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
224+instance (Reflex t, Monad m) => HasFocus t (VtyWidget t m) where
225+ focus = VtyWidget . lift $ asks _vtyWidgetCtx_focus
180226
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
227+-- | A class for widgets that can produce images to draw to the display
228+class (Reflex t, Monad m) => ImageWriter t m | m -> t where
229+ -- | Send images upstream for rendering
230+ tellImages :: Behavior t [Image] -> m ()
219231
220−-- * Getting and setting the display region
232+instance (Monad m, Reflex t) => ImageWriter t (BehaviorWriterT t [Image] m) where
233+ tellImages = tellBehavior
221234
222235-- | A chunk of the display area
223236data Region = Region
@@ -228,334 +241,467 @@ data Region = Region
228241 }
229242 deriving (Show, Read, Eq, Ord)
230243
231−-- | A region that occupies no space.
232−nilRegion :: Region
233−nilRegion = Region 0 0 0 0
234−
235244-- | The width and height of a 'Region'
236245regionSize :: Region -> (Int, Int)
237246regionSize (Region _ _ w h) = (w, h)
238247
239248-- | 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
249+regionBlankImage :: Region -> Image
250+regionBlankImage r@(Region _ _ width height) =
251+ withinImage r $ V.charFill V.defAttr ' ' width height
306252
307−instance MonadNodeId m => MonadNodeId (DisplayRegion t m)
253+-- | Translates and crops an 'Image' so that it is contained by
254+-- the given 'Region'.
255+withinImage
256+ :: Region
257+ -> Image
258+ -> Image
259+withinImage (Region left top width height)
260+ | width < 0 || height < 0 = withinImage (Region left top 0 0)
261+ | otherwise = V.translate left top . V.crop width height
308262
309−-- | Run a 'DisplayRegion' action with a given 'Region'
310−runDisplayRegion
311− :: (Reflex t, Monad m)
263+-- | Low-level widget combinator that runs a child 'VtyWidget' within
264+-- a given region and context. This widget filters and modifies the input
265+-- that the child widget receives such that:
266+-- * unfocused widgets receive no key events
267+-- * mouse inputs outside the region are ignored
268+-- * mouse inputs inside the region have their coordinates translated such
269+-- that (0,0) is the top-left corner of the region
270+pane
271+ :: (Reflex t, Monad m, MonadNodeId m)
312272 => 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)
358−
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
273+ -> Dynamic t Bool -- ^ Whether the widget should be focused when the parent is.
274+ -> VtyWidget t m a
275+ -> VtyWidget t m a
276+pane dr foc child = VtyWidget $ do
277+ ctx <- lift ask
278+ let reg = current dr
279+ let ctx' = VtyWidgetCtx
280+ { _vtyWidgetCtx_input = leftmost -- TODO: think about this leftmost more.
281+ [ fmapMaybe id $
282+ attachWith (\(r,f) e -> filterInput r f e)
283+ (liftA2 (,) reg (current foc))
284+ (_vtyWidgetCtx_input ctx)
285+ ]
286+ , _vtyWidgetCtx_focus = liftA2 (&&) (_vtyWidgetCtx_focus ctx) foc
287+ , _vtyWidgetCtx_width = _region_width <$> dr
288+ , _vtyWidgetCtx_height = _region_height <$> dr
289+ }
290+ (result, images) <- lift . lift $ runVtyWidget ctx' child
291+ let images' = liftA2 (\r is -> map (withinImage r) is) reg images
292+ tellImages images'
293+ return result
294+ where
295+ filterInput :: Region -> Bool -> VtyEvent -> Maybe VtyEvent
296+ filterInput (Region l t w h) focused e = case e of
297+ V.EvKey _ _ | not focused -> Nothing
298+ V.EvMouseDown x y btn m -> mouse (\u v -> V.EvMouseDown u v btn m) x y
299+ V.EvMouseUp x y btn -> mouse (\u v -> V.EvMouseUp u v btn) x y
300+ _ -> Just e
301+ where
302+ mouse con x y
303+ | or [ x < l
304+ , y < t
305+ , x >= l + w
306+ , y >= t + h ] = Nothing
307+ | otherwise =
308+ Just (con (x - l) (y - t))
309+
310+-- | Information about a drag operation
311+data Drag = Drag
312+ { _drag_from :: (Int, Int) -- ^ Where the drag began
313+ , _drag_to :: (Int, Int) -- ^ Where the mouse currently is
314+ , _drag_button :: V.Button -- ^ Which mouse button is dragging
315+ , _drag_modifiers :: [V.Modifier] -- ^ What modifiers are held
316+ , _drag_end :: Bool -- ^ Whether the drag ended (the mouse button was released)
317+ }
318+ deriving (Eq, Ord, Show)
319+
320+-- | Converts raw vty mouse drag events into an event stream of 'Drag's
321+drag
322+ :: (Reflex t, MonadFix m, MonadHold t m)
323+ => V.Button
324+ -> VtyWidget t m (Event t Drag)
325+drag btn = do
326+ inp <- input
327+ let f :: Maybe Drag -> V.Event -> Maybe Drag
328+ f Nothing = \case
329+ V.EvMouseDown x y btn' mods
330+ | btn == btn' -> Just $ Drag (x,y) (x,y) btn' mods False
331+ | otherwise -> Nothing
332+ _ -> Nothing
333+ f (Just (Drag from _ _ mods end)) = \case
334+ V.EvMouseDown x y btn' mods'
335+ | end && btn == btn' -> Just $ Drag (x,y) (x,y) btn' mods' False
336+ | btn == btn' -> Just $ Drag from (x,y) btn mods' False
337+ | otherwise -> Nothing -- Ignore other buttons.
338+ V.EvMouseUp x y (Just btn')
339+ | end -> Nothing
340+ | btn == btn' -> Just $ Drag from (x,y) btn mods True
341+ | otherwise -> Nothing
342+ V.EvMouseUp x y Nothing -- Terminal doesn't specify mouse up button,
343+ -- assume it's the right one.
344+ | end -> Nothing
345+ | otherwise -> Just $ Drag from (x,y) btn mods True
346+ _ -> Nothing
347+ rec let newDrag = attachWithMaybe f (current dragD) inp
348+ dragD <- holdDyn Nothing $ Just <$> newDrag
349+ return (fmapMaybe id $ updated dragD)
350+
351+-- | Mouse down events for a particular mouse button
352+mouseDown
375353 :: (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
354+ => V.Button
355+ -> VtyWidget t m (Event t MouseDown)
356+mouseDown btn = do
357+ i <- input
358+ return $ fforMaybe i $ \case
359+ V.EvMouseDown x y btn' mods -> if btn == btn'
360+ then Just $ MouseDown btn' (x, y) mods
361+ else Nothing
362+ _ -> Nothing
418363
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
364+-- | Mouse up events for a particular mouse button
365+mouseUp
366+ :: (Reflex t, Monad m)
367+ => VtyWidget t m (Event t MouseUp)
368+mouseUp = do
369+ i <- input
370+ return $ fforMaybe i $ \case
371+ V.EvMouseUp x y btn' -> Just $ MouseUp btn' (x, y)
372+ _ -> Nothing
424373
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)
374+-- | Information about a mouse down event
375+data MouseDown = MouseDown
376+ { _mouseDown_button :: V.Button
377+ , _mouseDown_coordinates :: (Int, Int)
378+ , _mouseDown_modifiers :: [V.Modifier]
379+ }
380+ deriving (Eq, Ord, Show)
430381
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
382+-- | Information about a mouse up event
383+data MouseUp = MouseUp
384+ { _mouseUp_button :: Maybe V.Button
385+ , _mouseUp_coordinates :: (Int, Int)
386+ }
387+ deriving (Eq, Ord, Show)
437388
438−instance HasDisplayRegion t m => HasDisplayRegion t (ImageWriter t m)
439−instance HasFocusReader t m => HasFocusReader t (ImageWriter t m)
389+-- | Mouse scroll direction
390+data ScrollDirection = ScrollDirection_Up | ScrollDirection_Down
391+ deriving (Eq, Ord, Show)
440392
441−-- | Run a widget that can produce images
442−runImageWriter
393+-- | Produce an event that fires when the mouse wheel is scrolled
394+mouseScroll
443395 :: (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
396+ => VtyWidget t m (Event t ScrollDirection)
397+mouseScroll = do
398+ up <- mouseDown V.BScrollUp
399+ down <- mouseDown V.BScrollDown
400+ return $ leftmost
401+ [ ScrollDirection_Up <$ up
402+ , ScrollDirection_Down <$ down
403+ ]
499404
500−instance MonadTrans (ThemeReader t) where
501− lift = ThemeReader . lift
405+-- | Type synonym for a key and modifier combination
406+type KeyCombo = (V.Key, [V.Modifier])
502407
503−instance MFunctor (ThemeReader t) where
504− hoist f = ThemeReader . hoist f . unThemeReader
408+-- | Emits an event that fires on a particular key press (without modifiers)
409+key :: (Monad m, Reflex t) => V.Key -> VtyWidget t m (Event t KeyCombo)
410+key = keyCombos . Set.singleton . (,[])
505411
506−instance MonadNodeId m => MonadNodeId (ThemeReader t m)
412+-- | Emits an event that fires on particular key presses (without modifiers)
413+keys :: (Monad m, Reflex t) => [V.Key] -> VtyWidget t m (Event t KeyCombo)
414+keys = keyCombos . Set.fromList . fmap (,[])
507415
508−-- | Run a 'ThemeReader' action with the given focus value
509−runThemeReader
416+-- | Emit an event that fires whenever the provided key combination occurs
417+keyCombo
510418 :: (Reflex t, Monad m)
511− => Behavior t V.Attr
512− -> ThemeReader t m a
513− -> m a
514−runThemeReader b = flip runReaderT b . unThemeReader
419+ => KeyCombo
420+ -> VtyWidget t m (Event t KeyCombo)
421+keyCombo = keyCombos . Set.singleton
515422
423+-- | Emit an event that fires whenever any of the provided key combinations occur
424+keyCombos
425+ :: (Reflex t, Monad m)
426+ => Set KeyCombo
427+ -> VtyWidget t m (Event t KeyCombo)
428+keyCombos ks = do
429+ i <- input
430+ return $ fforMaybe i $ \case
431+ V.EvKey k m -> if Set.member (k, m) ks
432+ then Just (k, m)
433+ else Nothing
434+ _ -> Nothing
516435
517−-- ** Manipulating images
436+-- | A plain split of the available space into vertically stacked panes.
437+-- No visual separator is built in here.
438+splitV :: (Reflex t, Monad m, MonadNodeId m)
439+ => Dynamic t (Int -> Int)
440+ -- ^ Function used to determine size of first pane based on available size
441+ -> Dynamic t (Bool, Bool)
442+ -- ^ How to focus the two sub-panes, given that we are focused.
443+ -> VtyWidget t m a
444+ -- ^ Widget for first pane
445+ -> VtyWidget t m b
446+ -- ^ Widget for second pane
447+ -> VtyWidget t m (a,b)
448+splitV sizeFunD focD wA wB = do
449+ dw <- displayWidth
450+ dh <- displayHeight
451+ let regA = Region 0 0 <$> dw <*> (sizeFunD <*> dh)
452+ regB = Region 0 <$> (_region_height <$> regA) <*> dw <*> liftA2 (-) dh (_region_height <$> regA)
453+ ra <- pane regA (fst <$> focD) wA
454+ rb <- pane regB (snd <$> focD) wB
455+ return (ra,rb)
456+
457+-- | A plain split of the available space into horizontally stacked panes.
458+-- No visual separator is built in here.
459+splitH :: (Reflex t, Monad m, MonadNodeId m)
460+ => Dynamic t (Int -> Int)
461+ -- ^ Function used to determine size of first pane based on available size
462+ -> Dynamic t (Bool, Bool)
463+ -- ^ How to focus the two sub-panes, given that we are focused.
464+ -> VtyWidget t m a
465+ -- ^ Widget for first pane
466+ -> VtyWidget t m b
467+ -- ^ Widget for second pane
468+ -> VtyWidget t m (a,b)
469+splitH sizeFunD focD wA wB = do
470+ dw <- displayWidth
471+ dh <- displayHeight
472+ let regA = Region 0 0 <$> (sizeFunD <*> dw) <*> dh
473+ regB = Region <$> (_region_width <$> regA) <*> 0 <*> liftA2 (-) dw (_region_width <$> regA) <*> dh
474+ liftA2 (,) (pane regA (fmap fst focD) wA) (pane regB (fmap snd focD) wB)
475+
476+-- | A split of the available space into two parts with a draggable separator.
477+-- Starts with half the space allocated to each, and the first pane has focus.
478+-- Clicking in a pane switches focus.
479+splitVDrag :: (Reflex t, MonadFix m, MonadHold t m, MonadNodeId m)
480+ => VtyWidget t m ()
481+ -> VtyWidget t m a
482+ -> VtyWidget t m b
483+ -> VtyWidget t m (a,b)
484+splitVDrag wS wA wB = do
485+ dh <- displayHeight
486+ dw <- displayWidth
487+ h0 <- sample $ current dh -- TODO
488+ dragE <- drag V.BLeft
489+ let splitter0 = h0 `div` 2
490+ rec splitterCheckpoint <- holdDyn splitter0 $ leftmost [fst <$> ffilter snd dragSplitter, resizeSplitter]
491+ splitterPos <- holdDyn splitter0 $ leftmost [fst <$> dragSplitter, resizeSplitter]
492+ splitterFrac <- holdDyn ((1::Double) / 2) $ ffor (attach (current dh) (fst <$> dragSplitter)) $ \(h, x) ->
493+ fromIntegral x / max 1 (fromIntegral h)
494+ let dragSplitter = fforMaybe (attach (current splitterCheckpoint) dragE) $
495+ \(splitterY, Drag (_, fromY) (_, toY) _ _ end) ->
496+ if splitterY == fromY then Just (toY, end) else Nothing
497+ regA = Region 0 0 <$> dw <*> splitterPos
498+ regS = Region 0 <$> splitterPos <*> dw <*> 1
499+ regB = Region 0 <$> (splitterPos + 1) <*> dw <*> (dh - splitterPos - 1)
500+ resizeSplitter = ffor (attach (current splitterFrac) (updated dh)) $
501+ \(frac, h) -> round (frac * fromIntegral h)
502+ focA <- holdDyn True $ leftmost
503+ [ True <$ mA
504+ , False <$ mB
505+ ]
506+ (mA, rA) <- pane regA focA $ withMouseDown wA
507+ pane regS (pure False) wS
508+ (mB, rB) <- pane regB (not <$> focA) $ withMouseDown wB
509+ return (rA, rB)
510+ where
511+ withMouseDown x = do
512+ m <- mouseDown V.BLeft
513+ x' <- x
514+ return (m, x')
515+
516+-- | Fill the background with a particular character.
517+fill :: (Reflex t, Monad m) => Char -> VtyWidget t m ()
518+fill c = do
519+ dw <- displayWidth
520+ dh <- displayHeight
521+ let fillImg = current $ liftA2 (\w h -> [V.charFill V.defAttr c w h]) dw dh
522+ tellImages fillImg
523+
524+-- | Fill the background with the bottom
525+hRule :: (Reflex t, Monad m) => BoxStyle -> VtyWidget t m ()
526+hRule boxStyle = fill (_boxStyle_s boxStyle)
527+
528+-- | Defines a set of symbols to use to draw the outlines of boxes
529+-- C.f. https://en.wikipedia.org/wiki/Box-drawing_character
530+data BoxStyle = BoxStyle
531+ { _boxStyle_nw :: Char
532+ , _boxStyle_n :: Char
533+ , _boxStyle_ne :: Char
534+ , _boxStyle_e :: Char
535+ , _boxStyle_se :: Char
536+ , _boxStyle_s :: Char
537+ , _boxStyle_sw :: Char
538+ , _boxStyle_w :: Char
539+ }
518540
519−-- | Translates and crops an 'Image' so that it is contained by
520−-- the given 'Region'.
521−withinImage
522− :: Region
523− -> Image
524− -> Image
525−withinImage (Region left top width height)
526− | width < 0 || height < 0 = withinImage (Region left top 0 0)
527− | otherwise = V.translate left top . V.crop width height
541+instance Default BoxStyle where
542+ def = singleBoxStyle
543+
544+-- | A box style that uses hyphens and pipe characters. Doesn't handle
545+-- corners very well.
546+hyphenBoxStyle :: BoxStyle
547+hyphenBoxStyle = BoxStyle '-' '-' '-' '|' '-' '-' '-' '|'
548+
549+-- | A single line box style
550+singleBoxStyle :: BoxStyle
551+singleBoxStyle = BoxStyle '┌' '─' '┐' '│' '┘' '─' '└' '│'
552+
553+-- | A thick single line box style
554+thickBoxStyle :: BoxStyle
555+thickBoxStyle = BoxStyle '┏' '━' '┓' '┃' '┛' '━' '┗' '┃'
556+
557+-- | A double line box style
558+doubleBoxStyle :: BoxStyle
559+doubleBoxStyle = BoxStyle '╔' '═' '╗' '║' '╝' '═' '╚' '║'
560+
561+-- | A single line box style with rounded corners
562+roundedBoxStyle :: BoxStyle
563+roundedBoxStyle = BoxStyle '╭' '─' '╮' '│' '╯' '─' '╰' '│'
564+
565+-- | Draws a titled box in the provided style and a child widget inside of that box
566+boxTitle :: (Monad m, Reflex t, MonadNodeId m)
567+ => Behavior t BoxStyle
568+ -> Text
569+ -> VtyWidget t m a
570+ -> VtyWidget t m a
571+boxTitle boxStyle title child = do
572+ dh <- displayHeight
573+ dw <- displayWidth
574+ let boxReg = Region 0 0 <$> dw <*> dh
575+ innerReg = Region 1 1 <$> (subtract 2 <$> dw) <*> (subtract 2 <$> dh)
576+ tellImages (boxImages <$> boxStyle <*> current boxReg)
577+ tellImages (fmap (\r -> [regionBlankImage r]) (current innerReg))
578+ pane innerReg (pure True) child
579+ where
580+ boxImages :: BoxStyle -> Region -> [Image]
581+ boxImages style (Region left top width height) =
582+ let right = left + width - 1
583+ bottom = top + height - 1
584+ sides =
585+ [ withinImage (Region (left + 1) top (width - 2) 1) $
586+ V.text' V.defAttr $
587+ hPadText title (_boxStyle_n style) (width - 2)
588+ , withinImage (Region right (top + 1) 1 (height - 2)) $
589+ V.charFill V.defAttr (_boxStyle_e style) 1 (height - 2)
590+ , withinImage (Region (left + 1) bottom (width - 2) 1) $
591+ V.charFill V.defAttr (_boxStyle_s style) (width - 2) 1
592+ , withinImage (Region left (top + 1) 1 (height - 2)) $
593+ V.charFill V.defAttr (_boxStyle_w style) 1 (height - 2)
594+ ]
595+ corners =
596+ [ withinImage (Region left top 1 1) $
597+ V.char V.defAttr (_boxStyle_nw style)
598+ , withinImage (Region right top 1 1) $
599+ V.char V.defAttr (_boxStyle_ne style)
600+ , withinImage (Region right bottom 1 1) $
601+ V.char V.defAttr (_boxStyle_se style)
602+ , withinImage (Region left bottom 1 1) $
603+ V.char V.defAttr (_boxStyle_sw style)
604+ ]
605+ in sides ++ if width > 1 && height > 1 then corners else []
606+ hPadText :: T.Text -> Char -> Int -> T.Text
607+ hPadText t c l = if lt >= l
608+ then t
609+ else left <> t <> right
610+ where
611+ lt = T.length t
612+ delta = l - lt
613+ mkHalf n = T.replicate (n `div` 2) (T.singleton c)
614+ left = mkHalf $ delta + 1
615+ right = mkHalf delta
616+
617+-- | A box without a title
618+box :: (Monad m, Reflex t, MonadNodeId m)
619+ => Behavior t BoxStyle
620+ -> VtyWidget t m a
621+ -> VtyWidget t m a
622+box boxStyle = boxTitle boxStyle mempty
623+
624+-- | A box whose style is static
625+boxStatic
626+ :: (Reflex t, Monad m, MonadNodeId m)
627+ => BoxStyle
628+ -> VtyWidget t m a
629+ -> VtyWidget t m a
630+boxStatic = box . pure
631+
632+-- | Configuration options for displaying "rich" text
633+data RichTextConfig t = RichTextConfig
634+ { _richTextConfig_attributes :: Behavior t V.Attr
635+ }
528636
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
637+instance Reflex t => Default (RichTextConfig t) where
638+ def = RichTextConfig $ pure V.defAttr
536639
537−-- * Running sub-widgets
640+-- | A widget that displays text with custom time-varying attributes
641+richText
642+ :: (Reflex t, Monad m)
643+ => RichTextConfig t
644+ -> Behavior t Text
645+ -> VtyWidget t m ()
646+richText cfg t = do
647+ dw <- displayWidth
648+ let img = (\w a s -> [wrapText w a s])
649+ <$> current dw
650+ <*> _richTextConfig_attributes cfg
651+ <*> t
652+ tellImages img
653+ where
654+ wrapText maxWidth attrs = V.vertCat
655+ . concatMap (fmap (V.string attrs . T.unpack) . TZ.wrapWithOffset maxWidth 0)
656+ . T.split (=='\n')
538657
539−-- | Low-level widget combinator that runs a child widget within
540−-- a given region and context. This widget filters and modifies the input
541−-- that the child widget receives such that:
542−-- * unfocused widgets receive no key events
543−-- * mouse inputs outside the region are ignored
544−-- * mouse inputs inside the region have their coordinates translated such
545−-- that (0,0) is the top-left corner of the region
546−pane
547− :: (Reflex t, Monad m, HasInput t m, HasImageWriter t m, HasDisplayRegion t m, HasFocusReader t m)
548− => Dynamic t Region
549− -> 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
658+-- | Renders text, wrapped to the container width
659+text
660+ :: (Reflex t, Monad m)
661+ => Behavior t Text
662+ -> VtyWidget t m ()
663+text = richText def
664+
665+-- | Scrollable text widget. The output pair exposes the current scroll position and total number of lines (including those
666+-- that are hidden)
667+scrollableText
668+ :: forall t m. (Reflex t, MonadHold t m, MonadFix m)
669+ => Event t Int
670+ -- ^ Number of lines to scroll by
671+ -> Behavior t Text
672+ -> VtyWidget t m (Behavior t (Int, Int))
673+ -- ^ (Current scroll position, total number of lines)
674+scrollableText scrollBy t = do
675+ dw <- displayWidth
676+ let imgs = wrap <$> current dw <*> t
677+ kup <- key V.KUp
678+ kdown <- key V.KDown
679+ m <- mouseScroll
680+ let requestedScroll :: Event t Int
681+ requestedScroll = leftmost
682+ [ 1 <$ kdown
683+ , (-1) <$ kup
684+ , ffor m $ \case
685+ ScrollDirection_Up -> (-1)
686+ ScrollDirection_Down -> 1
687+ , scrollBy
688+ ]
689+ updateLine maxN delta ix = min (max 0 (ix + delta)) maxN
690+ lineIndex :: Dynamic t Int <- foldDyn (\(maxN, delta) ix -> updateLine (maxN - 1) delta ix) 0 $
691+ attach (length <$> imgs) requestedScroll
692+ tellImages $ fmap ((:[]) . V.vertCat) $ drop <$> current lineIndex <*> imgs
693+ return $ (,) <$> ((+) <$> current lineIndex <*> pure 1) <*> (length <$> imgs)
694+ where
695+ wrap maxWidth = concatMap (fmap (V.string V.defAttr . T.unpack) . TZ.wrapWithOffset maxWidth 0) . T.split (=='\n')
556696
557−-- * Misc
697+-- | Renders any behavior whose value can be converted to
698+-- 'String' as text
699+display
700+ :: (Reflex t, Monad m, Show a)
701+ => Behavior t a
702+ -> VtyWidget t m ()
703+display a = text $ T.pack . show <$> a
558704
559705-- | A widget that draws nothing
560−blank :: Monad m => m ()
706+blank :: Monad m => VtyWidget t m ()
561707blank = return ()