@@ -2,41 +2,159 @@
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+ , ScrollDirection(..)
43+ , mouseScroll
44+ , pane
45+ , splitV
46+ , splitVDrag
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)
1071import 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)
72+import Control.Monad.Reader
73+import Control.Monad.Trans (lift)
74+import Data.Default (Default(..))
1775import Data.Set (Set)
1876import qualified Data.Set as Set
77+import Data.Text (Text)
78+import qualified Data.Text as T
79+import qualified Data.Text.Zipper as TZ
1980import Graphics.Vty (Image)
2081import qualified Graphics.Vty as V
2182import Reflex
2283import Reflex.Class ()
2384import Reflex.Host.Class (MonadReflexCreateTrigger)
85+
2486import Reflex.Vty.Host
2587
26−-- * Running a vty application
88+import Control.Monad.NodeId
89+
90+-- | The context within which a 'VtyWidget' runs
91+data VtyWidgetCtx t = VtyWidgetCtx
92+ { _vtyWidgetCtx_width :: Dynamic t Int
93+ -- ^ The width of the region allocated to the widget.
94+ , _vtyWidgetCtx_height :: Dynamic t Int
95+ -- ^ The height of the region allocated to the widget.
96+ , _vtyWidgetCtx_focus :: Dynamic t Bool
97+ -- ^ Whether the widget should behave as if it has focus for keyboard input.
98+ , _vtyWidgetCtx_input :: Event t VtyEvent
99+ -- ^ User input events that the widget's parent chooses to share. These will generally
100+ -- be filtered for relevance:
101+ -- * Keyboard inputs are restricted to focused widgets
102+ -- * Mouse inputs are restricted to the region in which the widget resides and are
103+ -- translated into its internal coordinates.
104+ }
105+
106+-- | The output of a 'VtyWidget'
107+data VtyWidgetOut t = VtyWidgetOut
108+ { _vtyWidgetOut_shutdown :: Event t ()
109+ }
110+
111+instance (Adjustable t m, MonadHold t m, Reflex t) => Adjustable t (VtyWidget t m) where
112+ runWithReplace a0 a' = VtyWidget $ runWithReplace (unVtyWidget a0) $ fmap unVtyWidget a'
113+ traverseIntMapWithKeyWithAdjust f dm0 dm' = VtyWidget $
114+ traverseIntMapWithKeyWithAdjust (\k v -> unVtyWidget (f k v)) dm0 dm'
115+ traverseDMapWithKeyWithAdjust f dm0 dm' = VtyWidget $ do
116+ traverseDMapWithKeyWithAdjust (\k v -> unVtyWidget (f k v)) dm0 dm'
117+ traverseDMapWithKeyWithAdjustWithMove f dm0 dm' = VtyWidget $ do
118+ traverseDMapWithKeyWithAdjustWithMove (\k v -> unVtyWidget (f k v)) dm0 dm'
119+
120+-- | A widget that can read its context and produce image output
121+newtype VtyWidget t m a = VtyWidget
122+ { unVtyWidget :: BehaviorWriterT t [Image] (ReaderT (VtyWidgetCtx t) m) a
123+ } deriving
124+ ( Functor
125+ , Applicative
126+ , Monad
127+ , MonadSample t
128+ , MonadHold t
129+ , MonadFix
130+ , NotReady t
131+ , ImageWriter t
132+ , PostBuild t
133+ , TriggerEvent t
134+ , MonadReflexCreateTrigger t
135+ , MonadIO
136+ )
137+
138+deriving instance PerformEvent t m => PerformEvent t (VtyWidget t m)
139+instance MonadTrans (VtyWidget t) where
140+ lift f = VtyWidget $ lift $ lift f
141+
142+instance MonadNodeId m => MonadNodeId (VtyWidget t m) where
143+ getNextNodeId = VtyWidget $ do
144+ lift $ lift $ getNextNodeId
145+
146+-- | Runs a 'VtyWidget' with a given context
147+runVtyWidget
148+ :: (Reflex t, MonadNodeId m)
149+ => VtyWidgetCtx t
150+ -> VtyWidget t m a
151+ -> m (a, Behavior t [Image])
152+runVtyWidget ctx w = runReaderT (runBehaviorWriterT (unVtyWidget w)) ctx
27153
28−-- | Sets up the top-level context for a vty widget and runs it with that context
154+-- | Sets up the top-level context for a 'VtyWidget' and runs it with that context
29155mainWidgetWithHandle
30156 :: 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 ()))
157+ -> (forall t m. (MonadVtyApp t m, MonadNodeId m) => VtyWidget t m (Event t ()))
40158 -> IO ()
41159mainWidgetWithHandle vty child =
42160 runVtyAppWithHandle vty $ \dr0 inp -> do
@@ -46,178 +164,71 @@ mainWidgetWithHandle vty child =
46164 let inp' = fforMaybe inp $ \case
47165 V.EvResize {} -> Nothing
48166 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
167+ let ctx = VtyWidgetCtx
168+ { _vtyWidgetCtx_width = fmap fst size
169+ , _vtyWidgetCtx_height = fmap snd size
170+ , _vtyWidgetCtx_input = inp'
171+ , _vtyWidgetCtx_focus = constDyn True
172+ }
173+ (shutdown, images) <- runNodeIdT $ runVtyWidget ctx $ do
174+ tellImages . ffor (current size) $ \(w, h) -> [V.charFill V.defAttr ' ' w h]
175+ child
57176 return $ VtyResult
58177 { _vtyResult_picture = fmap (V.picForLayers . reverse) images
59178 , _vtyResult_shutdown = shutdown
60179 }
61180
62−-- | The output of a vty widget
63−data VtyWidgetOut t = VtyWidgetOut
64− { _vtyWidgetOut_shutdown :: Event t ()
65− }
66−
67181-- | Like 'mainWidgetWithHandle', but uses a default vty configuration
68182mainWidget
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 ()))
183+ :: (forall t m. (MonadVtyApp t m, MonadNodeId m) => VtyWidget t m (Event t ()))
78184 -> IO ()
79185mainWidget child = do
80186 vty <- getDefaultVty
81187 mainWidgetWithHandle vty child
82188
83−-- * Input Events
189+-- | A class for things that know their own display size dimensions
190+class (Reflex t, Monad m) => HasDisplaySize t m | m -> t where
191+ -- | Retrieve the display width (columns)
192+ displayWidth :: m (Dynamic t Int)
193+ default displayWidth :: (f m' ~ m, MonadTrans f, HasDisplaySize t m') => m (Dynamic t Int)
194+ displayWidth = lift displayWidth
195+ -- | Retrieve the display height (rows)
196+ displayHeight :: m (Dynamic t Int)
197+ default displayHeight :: (f m' ~ m, MonadTrans f, HasDisplaySize t m') => m (Dynamic t Int)
198+ displayHeight = lift displayHeight
199+
200+instance (Reflex t, Monad m) => HasDisplaySize t (VtyWidget t m) where
201+ displayWidth = VtyWidget . lift $ asks _vtyWidgetCtx_width
202+ displayHeight = VtyWidget . lift $ asks _vtyWidgetCtx_height
203+
204+instance HasDisplaySize t m => HasDisplaySize t (ReaderT x m)
205+instance HasDisplaySize t m => HasDisplaySize t (BehaviorWriterT t x m)
206+instance HasDisplaySize t m => HasDisplaySize t (DynamicWriterT t x m)
207+instance HasDisplaySize t m => HasDisplaySize t (EventWriterT t x m)
208+
209+instance HasDisplaySize t m => HasDisplaySize t (NodeIdT m)
84210
85211-- | A class for things that can receive vty events as input
86−class HasInput t m | m -> t where
212+class HasVtyInput t m | m -> t where
87213 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− )
113−
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
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 . (,[])
215+instance (Reflex t, Monad m) => HasVtyInput t (VtyWidget t m) where
216+ input = VtyWidget . lift $ asks _vtyWidgetCtx_input
156217
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
218+-- | A class for things that can dynamically gain and lose focus
219+class HasFocus t m | m -> t where
220+ focus :: m (Dynamic t Bool)
167221
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
222+instance (Reflex t, Monad m) => HasFocus t (VtyWidget t m) where
223+ focus = VtyWidget . lift $ asks _vtyWidgetCtx_focus
180224
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
225+-- | A class for widgets that can produce images to draw to the display
226+class (Reflex t, Monad m) => ImageWriter t m | m -> t where
227+ -- | Send images upstream for rendering
228+ tellImages :: Behavior t [Image] -> m ()
219229
220−-- * Getting and setting the display region
230+instance (Monad m, Reflex t) => ImageWriter t (BehaviorWriterT t [Image] m) where
231+ tellImages = tellBehavior
221232
222233-- | A chunk of the display area
223234data Region = Region
@@ -228,334 +239,451 @@ data Region = Region
228239 }
229240 deriving (Show, Read, Eq, Ord)
230241
231−-- | A region that occupies no space.
232−nilRegion :: Region
233−nilRegion = Region 0 0 0 0
242+-- | A dynamic chunk of the display area
243+data DynRegion t = DynRegion
244+ { _dynRegion_left :: Dynamic t Int
245+ , _dynRegion_top :: Dynamic t Int
246+ , _dynRegion_width :: Dynamic t Int
247+ , _dynRegion_height :: Dynamic t Int
248+ }
234249
235250-- | The width and height of a 'Region'
236251regionSize :: Region -> (Int, Int)
237252regionSize (Region _ _ w h) = (w, h)
238253
239254-- | 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
255+regionBlankImage :: Region -> Image
256+regionBlankImage r@(Region _ _ width height) =
257+ withinImage r $ V.charFill V.defAttr ' ' width height
243258
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
259+-- | A behavior of the current display area represented by a 'DynRegion'
260+currentRegion :: Reflex t => DynRegion t -> Behavior t Region
261+currentRegion (DynRegion l t w h) = Region <$> current l <*> current t <*> current w <*> current h
306262
307−instance MonadNodeId m => MonadNodeId (DisplayRegion t m)
263+-- | Translates and crops an 'Image' so that it is contained by
264+-- the given 'Region'.
265+withinImage
266+ :: Region
267+ -> Image
268+ -> Image
269+withinImage (Region left top width height)
270+ | width < 0 || height < 0 = withinImage (Region left top 0 0)
271+ | otherwise = V.translate left top . V.crop width height
308272
309−-- | Run a 'DisplayRegion' action with a given 'Region'
310−runDisplayRegion
273+-- | Low-level widget combinator that runs a child 'VtyWidget' within
274+-- a given region and context. This widget filters and modifies the input
275+-- that the child widget receives such that:
276+-- * unfocused widgets receive no key events
277+-- * mouse inputs outside the region are ignored
278+-- * mouse inputs inside the region have their coordinates translated such
279+-- that (0,0) is the top-left corner of the region
280+pane
281+ :: (Reflex t, Monad m, MonadNodeId m)
282+ => DynRegion t
283+ -> Dynamic t Bool -- ^ Whether the widget should be focused when the parent is.
284+ -> VtyWidget t m a
285+ -> VtyWidget t m a
286+pane dr foc child = VtyWidget $ do
287+ ctx <- lift ask
288+ let reg = currentRegion dr
289+ let ctx' = VtyWidgetCtx
290+ { _vtyWidgetCtx_input = leftmost -- TODO: think about this leftmost more.
291+ [ fmapMaybe id $
292+ attachWith (\(r,f) e -> filterInput r f e)
293+ (liftA2 (,) reg (current foc))
294+ (_vtyWidgetCtx_input ctx)
295+ ]
296+ , _vtyWidgetCtx_focus = liftA2 (&&) (_vtyWidgetCtx_focus ctx) foc
297+ , _vtyWidgetCtx_width = _dynRegion_width dr
298+ , _vtyWidgetCtx_height = _dynRegion_height dr
299+ }
300+ (result, images) <- lift . lift $ runVtyWidget ctx' child
301+ let images' = liftA2 (\r is -> map (withinImage r) is) reg images
302+ tellImages images'
303+ return result
304+ where
305+ filterInput :: Region -> Bool -> VtyEvent -> Maybe VtyEvent
306+ filterInput (Region l t w h) focused e = case e of
307+ V.EvKey _ _ | not focused -> Nothing
308+ V.EvMouseDown x y btn m -> mouse (\u v -> V.EvMouseDown u v btn m) x y
309+ V.EvMouseUp x y btn -> mouse (\u v -> V.EvMouseUp u v btn) x y
310+ _ -> Just e
311+ where
312+ mouse con x y
313+ | or [ x < l
314+ , y < t
315+ , x >= l + w
316+ , y >= t + h ] = Nothing
317+ | otherwise =
318+ Just (con (x - l) (y - t))
319+
320+-- | Information about a drag operation
321+data Drag = Drag
322+ { _drag_from :: (Int, Int) -- ^ Where the drag began
323+ , _drag_to :: (Int, Int) -- ^ Where the mouse currently is
324+ , _drag_button :: V.Button -- ^ Which mouse button is dragging
325+ , _drag_modifiers :: [V.Modifier] -- ^ What modifiers are held
326+ , _drag_end :: Bool -- ^ Whether the drag ended (the mouse button was released)
327+ }
328+ deriving (Eq, Ord, Show)
329+
330+-- | Converts raw vty mouse drag events into an event stream of 'Drag's
331+drag
332+ :: (Reflex t, MonadFix m, MonadHold t m)
333+ => V.Button
334+ -> VtyWidget t m (Event t Drag)
335+drag btn = do
336+ inp <- input
337+ let f :: Maybe Drag -> V.Event -> Maybe Drag
338+ f Nothing = \case
339+ V.EvMouseDown x y btn' mods
340+ | btn == btn' -> Just $ Drag (x,y) (x,y) btn' mods False
341+ | otherwise -> Nothing
342+ _ -> Nothing
343+ f (Just (Drag from _ _ mods end)) = \case
344+ V.EvMouseDown x y btn' mods'
345+ | end -> Just $ Drag (x,y) (x,y) btn' mods' False
346+ | btn == btn' -> Just $ Drag from (x,y) btn mods' False
347+ | otherwise -> Nothing -- Ignore other buttons.
348+ V.EvMouseUp x y (Just btn')
349+ | end -> Nothing
350+ | btn == btn' -> Just $ Drag from (x,y) btn mods True
351+ | otherwise -> Nothing
352+ V.EvMouseUp x y Nothing -- Terminal doesn't specify mouse up button,
353+ -- assume it's the right one.
354+ | end -> Nothing
355+ | otherwise -> Just $ Drag from (x,y) btn mods True
356+ _ -> Nothing
357+ rec let newDrag = attachWithMaybe f (current dragD) inp
358+ dragD <- holdDyn Nothing $ Just <$> newDrag
359+ return (fmapMaybe id $ updated dragD)
360+
361+-- | Mouse down events for a particular mouse button
362+mouseDown
311363 :: (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)
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)
364+ => V.Button
365+ -> VtyWidget t m (Event t MouseDown)
366+mouseDown btn = do
367+ i <- input
368+ return $ fforMaybe i $ \case
369+ V.EvMouseDown x y btn' mods -> if btn == btn'
370+ then Just $ MouseDown btn' (x, y) mods
371+ else Nothing
372+ _ -> Nothing
372373
373−-- | Run a 'FocusReader' action with the given focus value
374−runFocusReader
374+-- | Mouse up events for a particular mouse button
375+mouseUp
375376 :: (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
377+ => VtyWidget t m (Event t MouseUp)
378+mouseUp = do
379+ i <- input
380+ return $ fforMaybe i $ \case
381+ V.EvMouseUp x y btn' -> Just $ MouseUp btn' (x, y)
382+ _ -> Nothing
424383
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)
384+-- | Information about a mouse down event
385+data MouseDown = MouseDown
386+ { _mouseDown_button :: V.Button
387+ , _mouseDown_coordinates :: (Int, Int)
388+ , _mouseDown_modifiers :: [V.Modifier]
389+ }
390+ deriving (Eq, Ord, Show)
430391
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
392+-- | Information about a mouse up event
393+data MouseUp = MouseUp
394+ { _mouseUp_button :: Maybe V.Button
395+ , _mouseUp_coordinates :: (Int, Int)
396+ }
397+ deriving (Eq, Ord, Show)
437398
438−instance HasDisplayRegion t m => HasDisplayRegion t (ImageWriter t m)
439−instance HasFocusReader t m => HasFocusReader t (ImageWriter t m)
399+-- | Mouse scroll direction
400+data ScrollDirection = ScrollDirection_Up | ScrollDirection_Down
401+ deriving (Eq, Ord, Show)
440402
441−-- | Run a widget that can produce images
442−runImageWriter
403+-- | Produce an event that fires when the mouse wheel is scrolled
404+mouseScroll
443405 :: (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
406+ => VtyWidget t m (Event t ScrollDirection)
407+mouseScroll = do
408+ up <- mouseDown V.BScrollUp
409+ down <- mouseDown V.BScrollDown
410+ return $ leftmost
411+ [ ScrollDirection_Up <$ up
412+ , ScrollDirection_Down <$ down
413+ ]
499414
500−instance MonadTrans (ThemeReader t) where
501− lift = ThemeReader . lift
415+-- | Type synonym for a key and modifier combination
416+type KeyCombo = (V.Key, [V.Modifier])
502417
503−instance MFunctor (ThemeReader t) where
504− hoist f = ThemeReader . hoist f . unThemeReader
418+-- | Emits an event that fires on a particular key press (without modifiers)
419+key :: (Monad m, Reflex t) => V.Key -> VtyWidget t m (Event t KeyCombo)
420+key = keyCombos . Set.singleton . (,[])
505421
506−instance MonadNodeId m => MonadNodeId (ThemeReader t m)
422+-- | Emits an event that fires on particular key presses (without modifiers)
423+keys :: (Monad m, Reflex t) => [V.Key] -> VtyWidget t m (Event t KeyCombo)
424+keys = keyCombos . Set.fromList . fmap (,[])
507425
508−-- | Run a 'ThemeReader' action with the given focus value
509−runThemeReader
426+-- | Emit an event that fires whenever the provided key combination occurs
427+keyCombo
510428 :: (Reflex t, Monad m)
511− => Behavior t V.Attr
512− -> ThemeReader t m a
513− -> m a
514−runThemeReader b = flip runReaderT b . unThemeReader
429+ => KeyCombo
430+ -> VtyWidget t m (Event t KeyCombo)
431+keyCombo = keyCombos . Set.singleton
515432
433+-- | Emit an event that fires whenever any of the provided key combinations occur
434+keyCombos
435+ :: (Reflex t, Monad m)
436+ => Set KeyCombo
437+ -> VtyWidget t m (Event t KeyCombo)
438+keyCombos ks = do
439+ i <- input
440+ return $ fforMaybe i $ \case
441+ V.EvKey k m -> if Set.member (k, m) ks
442+ then Just (k, m)
443+ else Nothing
444+ _ -> Nothing
516445
517−-- ** Manipulating images
446+-- | A plain split of the available space into vertically stacked panes.
447+-- No visual separator is built in here.
448+splitV :: (Reflex t, Monad m, MonadNodeId m)
449+ => Dynamic t (Int -> Int)
450+ -- ^ Function used to determine size of first pane based on available size
451+ -> Dynamic t (Bool, Bool)
452+ -- ^ How to focus the two sub-panes, given that we are focused.
453+ -> VtyWidget t m a
454+ -- ^ Widget for first pane
455+ -> VtyWidget t m b
456+ -- ^ Widget for second pane
457+ -> VtyWidget t m (a,b)
458+splitV sizeFunD focD wA wB = do
459+ dw <- displayWidth
460+ dh <- displayHeight
461+ let regA = DynRegion
462+ { _dynRegion_left = pure 0
463+ , _dynRegion_top = pure 0
464+ , _dynRegion_width = dw
465+ , _dynRegion_height = sizeFunD <*> dh
466+ }
467+ regB = DynRegion
468+ { _dynRegion_left = pure 0
469+ , _dynRegion_top = _dynRegion_height regA
470+ , _dynRegion_width = dw
471+ , _dynRegion_height = liftA2 (-) dh (_dynRegion_height regA)
472+ }
473+ ra <- pane regA (fst <$> focD) wA
474+ rb <- pane regB (snd <$> focD) wB
475+ return (ra,rb)
476+
477+-- | A split of the available space into two parts with a draggable separator.
478+-- Starts with half the space allocated to each, and the first pane has focus.
479+-- Clicking in a pane switches focus.
480+splitVDrag :: (Reflex t, MonadFix m, MonadHold t m, MonadNodeId m)
481+ => VtyWidget t m ()
482+ -> VtyWidget t m a
483+ -> VtyWidget t m b
484+ -> VtyWidget t m (a,b)
485+splitVDrag wS wA wB = do
486+ dh <- displayHeight
487+ dw <- displayWidth
488+ h0 <- sample $ current dh -- TODO
489+ dragE <- drag V.BLeft
490+ let splitter0 = h0 `div` 2
491+ rec splitterCheckpoint <- holdDyn splitter0 $ leftmost [fst <$> ffilter snd dragSplitter, resizeSplitter]
492+ splitterPos <- holdDyn splitter0 $ leftmost [fst <$> dragSplitter, resizeSplitter]
493+ splitterFrac <- holdDyn ((1::Double) / 2) $ ffor (attach (current dh) (fst <$> dragSplitter)) $ \(h, x) ->
494+ fromIntegral x / (max 1 (fromIntegral h))
495+ let dragSplitter = fforMaybe (attach (current splitterCheckpoint) dragE) $
496+ \(splitterY, Drag (_, fromY) (_, toY) _ _ end) ->
497+ if splitterY == fromY then Just (toY, end) else Nothing
498+ regA = DynRegion 0 0 dw splitterPos
499+ regS = DynRegion 0 splitterPos dw 1
500+ regB = DynRegion 0 (splitterPos + 1) dw (dh - splitterPos - 1)
501+ resizeSplitter = ffor (attach (current splitterFrac) (updated dh)) $
502+ \(frac, h) -> round (frac * fromIntegral h)
503+ focA <- holdDyn True $ leftmost
504+ [ True <$ mA
505+ , False <$ mB
506+ ]
507+ (mA, rA) <- pane regA focA $ withMouseDown wA
508+ pane regS (pure False) wS
509+ (mB, rB) <- pane regB (not <$> focA) $ withMouseDown wB
510+ return (rA, rB)
511+ where
512+ withMouseDown x = do
513+ m <- mouseDown V.BLeft
514+ x' <- x
515+ return (m, x')
516+
517+-- | Fill the background with a particular character.
518+fill :: (Reflex t, Monad m) => Char -> VtyWidget t m ()
519+fill c = do
520+ dw <- displayWidth
521+ dh <- displayHeight
522+ let fillImg = current $ liftA2 (\w h -> [V.charFill V.defAttr c w h]) dw dh
523+ tellImages fillImg
524+
525+-- | Fill the background with the bottom
526+hRule :: (Reflex t, Monad m) => BoxStyle -> VtyWidget t m ()
527+hRule boxStyle = fill (_boxStyle_s boxStyle)
528+
529+-- | Defines a set of symbols to use to draw the outlines of boxes
530+-- C.f. https://en.wikipedia.org/wiki/Box-drawing_character
531+data BoxStyle = BoxStyle
532+ { _boxStyle_nw :: Char
533+ , _boxStyle_n :: Char
534+ , _boxStyle_ne :: Char
535+ , _boxStyle_e :: Char
536+ , _boxStyle_se :: Char
537+ , _boxStyle_s :: Char
538+ , _boxStyle_sw :: Char
539+ , _boxStyle_w :: Char
540+ }
518541
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
542+instance Default BoxStyle where
543+ def = singleBoxStyle
544+
545+-- | A box style that uses hyphens and pipe characters. Doesn't handle
546+-- corners very well.
547+hyphenBoxStyle :: BoxStyle
548+hyphenBoxStyle = BoxStyle '-' '-' '-' '|' '-' '-' '-' '|'
549+
550+-- | A single line box style
551+singleBoxStyle :: BoxStyle
552+singleBoxStyle = BoxStyle '┌' '─' '┐' '│' '┘' '─' '└' '│'
553+
554+-- | A thick single line box style
555+thickBoxStyle :: BoxStyle
556+thickBoxStyle = BoxStyle '┏' '━' '┓' '┃' '┛' '━' '┗' '┃'
557+
558+-- | A double line box style
559+doubleBoxStyle :: BoxStyle
560+doubleBoxStyle = BoxStyle '╔' '═' '╗' '║' '╝' '═' '╚' '║'
561+
562+-- | A single line box style with rounded corners
563+roundedBoxStyle :: BoxStyle
564+roundedBoxStyle = BoxStyle '╭' '─' '╮' '│' '╯' '─' '╰' '│'
565+
566+-- | Draws a box in the provided style and a child widget inside of that box
567+box :: (Monad m, Reflex t, MonadNodeId m)
568+ => Behavior t BoxStyle
569+ -> VtyWidget t m a
570+ -> VtyWidget t m a
571+box boxStyle child = do
572+ dh <- displayHeight
573+ dw <- displayWidth
574+ let boxReg = DynRegion (pure 0) (pure 0) dw dh
575+ innerReg = DynRegion (pure 1) (pure 1) (subtract 2 <$> dw) (subtract 2 <$> dh)
576+ tellImages (boxImages <$> boxStyle <*> currentRegion boxReg)
577+ tellImages (fmap (\r -> [regionBlankImage r]) (currentRegion 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.charFill V.defAttr (_boxStyle_n style) (width - 2) 1
587+ , withinImage (Region right (top + 1) 1 (height - 2)) $
588+ V.charFill V.defAttr (_boxStyle_e style) 1 (height - 2)
589+ , withinImage (Region (left + 1) bottom (width - 2) 1) $
590+ V.charFill V.defAttr (_boxStyle_s style) (width - 2) 1
591+ , withinImage (Region left (top + 1) 1 (height - 2)) $
592+ V.charFill V.defAttr (_boxStyle_w style) 1 (height - 2)
593+ ]
594+ corners =
595+ [ withinImage (Region left top 1 1) $
596+ V.char V.defAttr (_boxStyle_nw style)
597+ , withinImage (Region right top 1 1) $
598+ V.char V.defAttr (_boxStyle_ne style)
599+ , withinImage (Region right bottom 1 1) $
600+ V.char V.defAttr (_boxStyle_se style)
601+ , withinImage (Region left bottom 1 1) $
602+ V.char V.defAttr (_boxStyle_sw style)
603+ ]
604+ in sides ++ if width > 1 && height > 1 then corners else []
605+
606+-- | A box whose style is static
607+boxStatic
608+ :: (Reflex t, Monad m, MonadNodeId m)
609+ => BoxStyle
610+ -> VtyWidget t m a
611+ -> VtyWidget t m a
612+boxStatic = box . pure
613+
614+-- | Configuration options for displaying "rich" text
615+data RichTextConfig t = RichTextConfig
616+ { _richTextConfig_attributes :: Behavior t V.Attr
617+ }
528618
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
619+instance Reflex t => Default (RichTextConfig t) where
620+ def = RichTextConfig $ pure V.defAttr
536621
537−-- * Running sub-widgets
622+-- | A widget that displays text with custom time-varying attributes
623+richText
624+ :: (Reflex t, Monad m)
625+ => RichTextConfig t
626+ -> Behavior t Text
627+ -> VtyWidget t m ()
628+richText cfg t = do
629+ dw <- displayWidth
630+ let img = (\w a s -> [wrapText w a s])
631+ <$> current dw
632+ <*> _richTextConfig_attributes cfg
633+ <*> t
634+ tellImages img
635+ where
636+ wrapText maxWidth attrs = V.vertCat
637+ . concatMap (fmap (V.string attrs . T.unpack) . TZ.wrapWithOffset maxWidth 0)
638+ . T.split (=='\n')
538639
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
640+-- | Renders text, wrapped to the container width
641+text
642+ :: (Reflex t, Monad m)
643+ => Behavior t Text
644+ -> VtyWidget t m ()
645+text = richText def
646+
647+-- | Scrollable text widget. The output pair exposes the current scroll position and total number of lines (including those
648+-- that are hidden)
649+scrollableText
650+ :: forall t m. (Reflex t, MonadHold t m, MonadFix m)
651+ => Event t Int
652+ -- ^ Number of lines to scroll by
653+ -> Behavior t Text
654+ -> VtyWidget t m (Behavior t (Int, Int))
655+ -- ^ (Current scroll position, total number of lines)
656+scrollableText scrollBy t = do
657+ dw <- displayWidth
658+ let imgs = wrap <$> current dw <*> t
659+ kup <- key V.KUp
660+ kdown <- key V.KDown
661+ m <- mouseScroll
662+ let requestedScroll :: Event t Int
663+ requestedScroll = leftmost
664+ [ 1 <$ kdown
665+ , (-1) <$ kup
666+ , ffor m $ \case
667+ ScrollDirection_Up -> (-1)
668+ ScrollDirection_Down -> 1
669+ , scrollBy
670+ ]
671+ updateLine maxN delta ix = min (max 0 (ix + delta)) maxN
672+ lineIndex :: Dynamic t Int <- foldDyn (\(maxN, delta) ix -> updateLine (maxN - 1) delta ix) 0 $
673+ attach (length <$> imgs) requestedScroll
674+ tellImages $ fmap ((:[]) . V.vertCat) $ drop <$> current lineIndex <*> imgs
675+ return $ (,) <$> ((+) <$> current lineIndex <*> pure 1) <*> (length <$> imgs)
676+ where
677+ wrap maxWidth = concatMap (fmap (V.string V.defAttr . T.unpack) . TZ.wrapWithOffset maxWidth 0) . T.split (=='\n')
556678
557−-- * Misc
679+-- | Renders any behavior whose value can be converted to
680+-- 'String' as text
681+display
682+ :: (Reflex t, Monad m, Show a)
683+ => Behavior t a
684+ -> VtyWidget t m ()
685+display a = text $ T.pack . show <$> a
558686
559687-- | A widget that draws nothing
560−blank :: Monad m => m ()
688+blank :: Monad m => VtyWidget t m ()
561689blank = return ()