@@ -2,162 +2,41 @@
22Module: Reflex.Vty.Widget
33Description: Basic set of widgets and building blocks for reflex-vty applications
44-}
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− , splitH
47− , splitVDrag
48− , boxTitle
49− , box
50− , boxStatic
51− , RichTextConfig(..)
52− , richText
53− , text
54− , scrollableText
55− , display
56− , BoxStyle(..)
57− , hyphenBoxStyle
58− , singleBoxStyle
59− , roundedBoxStyle
60− , thickBoxStyle
61− , doubleBoxStyle
62− , fill
63− , hRule
64− , KeyCombo
65− , key
66− , keys
67− , keyCombo
68− , keyCombos
69− , blank
70− ) where
5+{-# Language UndecidableInstances #-}
6+
7+module Reflex.Vty.Widget where
718
729import Control.Applicative (liftA2)
7310import Control.Monad.Fix (MonadFix)
7411import Control.Monad.IO.Class (MonadIO)
75−import Control.Monad.Reader (ReaderT, ask, asks, runReaderT)
12+import Control.Monad.Morph
13+import Control.Monad.NodeId
14+import Control.Monad.Reader (ReaderT, ask, local, runReaderT)
15+import Control.Monad.Ref
7616import Control.Monad.Trans (MonadTrans, lift)
77−import Data.Default (Default(..))
7817import Data.Set (Set)
7918import qualified Data.Set as Set
80−import Data.Text (Text)
81−import qualified Data.Text as T
82−import qualified Data.Text.Zipper as TZ
8319import Graphics.Vty (Image)
8420import qualified Graphics.Vty as V
8521import Reflex
8622import Reflex.Class ()
8723import Reflex.Host.Class (MonadReflexCreateTrigger)
88−
8924import Reflex.Vty.Host
9025
91−import Control.Monad.NodeId
92−
93−-- | The context within which a 'VtyWidget' runs
94−data VtyWidgetCtx t = VtyWidgetCtx
95− { _vtyWidgetCtx_width :: Dynamic t Int
96− -- ^ The width of the region allocated to the widget.
97− , _vtyWidgetCtx_height :: Dynamic t Int
98− -- ^ The height of the region allocated to the widget.
99− , _vtyWidgetCtx_focus :: Dynamic t Bool
100− -- ^ Whether the widget should behave as if it has focus for keyboard input.
101− , _vtyWidgetCtx_input :: Event t VtyEvent
102− -- ^ User input events that the widget's parent chooses to share. These will generally
103− -- be filtered for relevance:
104− -- * Keyboard inputs are restricted to focused widgets
105− -- * Mouse inputs are restricted to the region in which the widget resides and are
106− -- translated into its internal coordinates.
107− }
108−
109−-- | The output of a 'VtyWidget'
110−data VtyWidgetOut t = VtyWidgetOut
111− { _vtyWidgetOut_shutdown :: Event t ()
112− }
113−
114−instance (Adjustable t m, MonadHold t m, Reflex t) => Adjustable t (VtyWidget t m) where
115− runWithReplace a0 a' = VtyWidget $ runWithReplace (unVtyWidget a0) $ fmap unVtyWidget a'
116− traverseIntMapWithKeyWithAdjust f dm0 dm' = VtyWidget $
117− traverseIntMapWithKeyWithAdjust (\k v -> unVtyWidget (f k v)) dm0 dm'
118− traverseDMapWithKeyWithAdjust f dm0 dm' = VtyWidget $ do
119− traverseDMapWithKeyWithAdjust (\k v -> unVtyWidget (f k v)) dm0 dm'
120− traverseDMapWithKeyWithAdjustWithMove f dm0 dm' = VtyWidget $ do
121− traverseDMapWithKeyWithAdjustWithMove (\k v -> unVtyWidget (f k v)) dm0 dm'
122−
123−-- | A widget that can read its context and produce image output
124−newtype VtyWidget t m a = VtyWidget
125− { unVtyWidget :: BehaviorWriterT t [Image] (ReaderT (VtyWidgetCtx t) m) a
126− } deriving
127− ( Functor
128− , Applicative
129− , Monad
130− , MonadSample t
131− , MonadHold t
132− , MonadFix
133− , NotReady t
134− , ImageWriter t
135− , PostBuild t
136− , TriggerEvent t
137− , MonadReflexCreateTrigger t
138− , MonadIO
139− )
140−
141−deriving instance PerformEvent t m => PerformEvent t (VtyWidget t m)
142−instance MonadTrans (VtyWidget t) where
143− lift f = VtyWidget $ lift $ lift f
144−
145−instance MonadNodeId m => MonadNodeId (VtyWidget t m) where
146− getNextNodeId = VtyWidget $ do
147− lift $ lift getNextNodeId
148−
149−-- | Runs a 'VtyWidget' with a given context
150−runVtyWidget
151− :: (Reflex t, MonadNodeId m)
152− => VtyWidgetCtx t
153− -> VtyWidget t m a
154− -> m (a, Behavior t [Image])
155−runVtyWidget ctx w = runReaderT (runBehaviorWriterT (unVtyWidget w)) ctx
26+-- * Running a vty application
15627
157−-- | Sets up the top-level context for a 'VtyWidget' and runs it with that context
28+-- | Sets up the top-level context for a vty widget and runs it with that context
15829mainWidgetWithHandle
15930 :: V.Vty
160− -> (forall t m. (MonadVtyApp t m, MonadNodeId m) => VtyWidget t m (Event t ()))
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 ()))
16140 -> IO ()
16241mainWidgetWithHandle vty child =
16342 runVtyAppWithHandle vty $ \dr0 inp -> do
@@ -167,71 +46,178 @@ mainWidgetWithHandle vty child =
16746 let inp' = fforMaybe inp $ \case
16847 V.EvResize {} -> Nothing
16948 x -> Just x
170− let ctx = VtyWidgetCtx
171− { _vtyWidgetCtx_width = fmap fst size
172− , _vtyWidgetCtx_height = fmap snd size
173− , _vtyWidgetCtx_input = inp'
174− , _vtyWidgetCtx_focus = constDyn True
175− }
176− (shutdown, images) <- runNodeIdT $ runVtyWidget ctx $ do
177− tellImages . ffor (current size) $ \(w, h) -> [V.charFill V.defAttr ' ' w h]
178− child
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
17957 return $ VtyResult
18058 { _vtyResult_picture = fmap (V.picForLayers . reverse) images
18159 , _vtyResult_shutdown = shutdown
18260 }
18361
62+-- | The output of a vty widget
63+data VtyWidgetOut t = VtyWidgetOut
64+ { _vtyWidgetOut_shutdown :: Event t ()
65+ }
66+
18467-- | Like 'mainWidgetWithHandle', but uses a default vty configuration
18568mainWidget
186− :: (forall t m. (MonadVtyApp t m, MonadNodeId m) => VtyWidget t m (Event t ()))
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 ()))
18778 -> IO ()
18879mainWidget child = do
18980 vty <- getDefaultVty
19081 mainWidgetWithHandle vty child
19182
192−-- | A class for things that know their own display size dimensions
193−class (Reflex t, Monad m) => HasDisplaySize t m | m -> t where
194− -- | Retrieve the display width (columns)
195− displayWidth :: m (Dynamic t Int)
196− default displayWidth :: (f m' ~ m, MonadTrans f, HasDisplaySize t m') => m (Dynamic t Int)
197− displayWidth = lift displayWidth
198− -- | Retrieve the display height (rows)
199− displayHeight :: m (Dynamic t Int)
200− default displayHeight :: (f m' ~ m, MonadTrans f, HasDisplaySize t m') => m (Dynamic t Int)
201− displayHeight = lift displayHeight
202−
203−instance (Reflex t, Monad m) => HasDisplaySize t (VtyWidget t m) where
204− displayWidth = VtyWidget . lift $ asks _vtyWidgetCtx_width
205− displayHeight = VtyWidget . lift $ asks _vtyWidgetCtx_height
206−
207−instance HasDisplaySize t m => HasDisplaySize t (ReaderT x m)
208−instance HasDisplaySize t m => HasDisplaySize t (BehaviorWriterT t x m)
209−instance HasDisplaySize t m => HasDisplaySize t (DynamicWriterT t x m)
210−instance HasDisplaySize t m => HasDisplaySize t (EventWriterT t x m)
211−
212−instance HasDisplaySize t m => HasDisplaySize t (NodeIdT m)
83+-- * Input Events
21384
21485-- | A class for things that can receive vty events as input
215−class HasVtyInput t m | m -> t where
86+class HasInput t m | m -> t where
21687 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+ )
217113
218−instance (Reflex t, Monad m) => HasVtyInput t (VtyWidget t m) where
219− input = VtyWidget . lift $ asks _vtyWidgetCtx_input
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
220149
221−-- | A class for things that can dynamically gain and lose focus
222−class HasFocus t m | m -> t where
223− focus :: m (Dynamic t Bool)
150+-- | Type synonym for a key and modifier combination
151+type KeyCombo = (V.Key, [V.Modifier])
224152
225−instance (Reflex t, Monad m) => HasFocus t (VtyWidget t m) where
226− focus = VtyWidget . lift $ asks _vtyWidgetCtx_focus
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 . (,[])
227156
228−-- | A class for widgets that can produce images to draw to the display
229−class (Reflex t, Monad m) => ImageWriter t m | m -> t where
230− -- | Send images upstream for rendering
231− tellImages :: Behavior t [Image] -> m ()
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 (,[])
232160
233−instance (Monad m, Reflex t) => ImageWriter t (BehaviorWriterT t [Image] m) where
234− tellImages = tellBehavior
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
167+
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
180+
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
219+
220+-- * Getting and setting the display region
235221
236222-- | A chunk of the display area
237223data Region = Region
@@ -242,499 +228,334 @@ data Region = Region
242228 }
243229 deriving (Show, Read, Eq, Ord)
244230
245−-- | A dynamic chunk of the display area
246−data DynRegion t = DynRegion
247− { _dynRegion_left :: Dynamic t Int
248− , _dynRegion_top :: Dynamic t Int
249− , _dynRegion_width :: Dynamic t Int
250− , _dynRegion_height :: Dynamic t Int
251− }
231+-- | A region that occupies no space.
232+nilRegion :: Region
233+nilRegion = Region 0 0 0 0
252234
253235-- | The width and height of a 'Region'
254236regionSize :: Region -> (Int, Int)
255237regionSize (Region _ _ w h) = (w, h)
256238
257239-- | Produces an 'Image' that fills a region with space characters
258−regionBlankImage :: Region -> Image
259−regionBlankImage r@(Region _ _ width height) =
260− withinImage r $ V.charFill V.defAttr ' ' width height
240+regionBlankImage :: V.Attr -> Region -> Image
241+regionBlankImage attr r@(Region _ _ width height) =
242+ withinImage r $ V.charFill attr ' ' width height
261243
262−-- | A behavior of the current display area represented by a 'DynRegion'
263−currentRegion :: Reflex t => DynRegion t -> Behavior t Region
264−currentRegion (DynRegion l t w h) = Region <$> current l <*> current t <*> current w <*> current h
244+-- | A class for things that know their own display size dimensions
245+class (Reflex t, Monad m) => HasDisplayRegion t m | m -> t where
246+ -- | Retrieve the display region
247+ askRegion :: m (Dynamic t Region)
248+ default askRegion :: (f m' ~ m, MonadTrans f, HasDisplayRegion t m') => m (Dynamic t Region)
249+ askRegion = lift askRegion
250+ -- | Run an action in a local region, by applying a transformation to the region
251+ localRegion :: (Dynamic t Region -> Dynamic t Region) -> m a -> m a
252+ default localRegion :: (f m' ~ m, Monad m', MFunctor f, HasDisplayRegion t m') => (Dynamic t Region -> Dynamic t Region) -> m a -> m a
253+ localRegion f = hoist (localRegion f)
254+
255+-- | Retrieve the display width
256+displayWidth :: HasDisplayRegion t m => m (Dynamic t Int)
257+displayWidth = fmap _region_width <$> 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+ )
265282
266−-- | Translates and crops an 'Image' so that it is contained by
267−-- the given 'Region'.
268−withinImage
269− :: Region
270− -> Image
271− -> Image
272−withinImage (Region left top width height)
273− | width < 0 || height < 0 = withinImage (Region left top 0 0)
274− | otherwise = V.translate left top . V.crop width height
283+instance (Monad m, Reflex t) => HasDisplayRegion t (DisplayRegion t m) where
284+ askRegion = DisplayRegion ask
285+ localRegion f = DisplayRegion . local f . unDisplayRegion
275286
276−-- | Low-level widget combinator that runs a child 'VtyWidget' within
277−-- a given region and context. This widget filters and modifies the input
278−-- that the child widget receives such that:
279−-- * unfocused widgets receive no key events
280−-- * mouse inputs outside the region are ignored
281−-- * mouse inputs inside the region have their coordinates translated such
282−-- that (0,0) is the top-left corner of the region
283−pane
284− :: (Reflex t, Monad m, MonadNodeId m)
285− => DynRegion t
286− -> Dynamic t Bool -- ^ Whether the widget should be focused when the parent is.
287− -> VtyWidget t m a
288− -> VtyWidget t m a
289−pane dr foc child = VtyWidget $ do
290− ctx <- lift ask
291− let reg = currentRegion dr
292− let ctx' = VtyWidgetCtx
293− { _vtyWidgetCtx_input = leftmost -- TODO: think about this leftmost more.
294− [ fmapMaybe id $
295− attachWith (\(r,f) e -> filterInput r f e)
296− (liftA2 (,) reg (current foc))
297− (_vtyWidgetCtx_input ctx)
298− ]
299− , _vtyWidgetCtx_focus = liftA2 (&&) (_vtyWidgetCtx_focus ctx) foc
300− , _vtyWidgetCtx_width = _dynRegion_width dr
301− , _vtyWidgetCtx_height = _dynRegion_height dr
302− }
303− (result, images) <- lift . lift $ runVtyWidget ctx' child
304− let images' = liftA2 (\r is -> map (withinImage r) is) reg images
305− tellImages images'
306− return result
307− where
308− filterInput :: Region -> Bool -> VtyEvent -> Maybe VtyEvent
309− filterInput (Region l t w h) focused e = case e of
310− V.EvKey _ _ | not focused -> Nothing
311− V.EvMouseDown x y btn m -> mouse (\u v -> V.EvMouseDown u v btn m) x y
312− V.EvMouseUp x y btn -> mouse (\u v -> V.EvMouseUp u v btn) x y
313− _ -> Just e
314− where
315− mouse con x y
316− | or [ x < l
317− , y < t
318− , x >= l + w
319− , y >= t + h ] = Nothing
320− | otherwise =
321− Just (con (x - l) (y - t))
322−
323−-- | Information about a drag operation
324−data Drag = Drag
325− { _drag_from :: (Int, Int) -- ^ Where the drag began
326− , _drag_to :: (Int, Int) -- ^ Where the mouse currently is
327− , _drag_button :: V.Button -- ^ Which mouse button is dragging
328− , _drag_modifiers :: [V.Modifier] -- ^ What modifiers are held
329− , _drag_end :: Bool -- ^ Whether the drag ended (the mouse button was released)
330− }
331− deriving (Eq, Ord, Show)
332−
333−-- | Converts raw vty mouse drag events into an event stream of 'Drag's
334−drag
335− :: (Reflex t, MonadFix m, MonadHold t m)
336− => V.Button
337− -> VtyWidget t m (Event t Drag)
338−drag btn = do
339− inp <- input
340− let f :: Maybe Drag -> V.Event -> Maybe Drag
341− f Nothing = \case
342− V.EvMouseDown x y btn' mods
343− | btn == btn' -> Just $ Drag (x,y) (x,y) btn' mods False
344− | otherwise -> Nothing
345− _ -> Nothing
346− f (Just (Drag from _ _ mods end)) = \case
347− V.EvMouseDown x y btn' mods'
348− | end && btn == btn' -> Just $ Drag (x,y) (x,y) btn' mods' False
349− | btn == btn' -> Just $ Drag from (x,y) btn mods' False
350− | otherwise -> Nothing -- Ignore other buttons.
351− V.EvMouseUp x y (Just btn')
352− | end -> Nothing
353− | btn == btn' -> Just $ Drag from (x,y) btn mods True
354− | otherwise -> Nothing
355− V.EvMouseUp x y Nothing -- Terminal doesn't specify mouse up button,
356− -- assume it's the right one.
357− | end -> Nothing
358− | otherwise -> Just $ Drag from (x,y) btn mods True
359− _ -> Nothing
360− rec let newDrag = attachWithMaybe f (current dragD) inp
361− dragD <- holdDyn Nothing $ Just <$> newDrag
362− return (fmapMaybe id $ updated dragD)
363−
364−-- | Mouse down events for a particular mouse button
365−mouseDown
366− :: (Reflex t, Monad m)
367− => V.Button
368− -> VtyWidget t m (Event t MouseDown)
369−mouseDown btn = do
370− i <- input
371− return $ fforMaybe i $ \case
372− V.EvMouseDown x y btn' mods -> if btn == btn'
373− then Just $ MouseDown btn' (x, y) mods
374− else Nothing
375− _ -> Nothing
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)
376294
377−-- | Mouse up events for a particular mouse button
378−mouseUp
379− :: (Reflex t, Monad m)
380− => VtyWidget t m (Event t MouseUp)
381−mouseUp = do
382− i <- input
383− return $ fforMaybe i $ \case
384− V.EvMouseUp x y btn' -> Just $ MouseUp btn' (x, y)
385− _ -> Nothing
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
386300
387−-- | Information about a mouse down event
388−data MouseDown = MouseDown
389− { _mouseDown_button :: V.Button
390− , _mouseDown_coordinates :: (Int, Int)
391− , _mouseDown_modifiers :: [V.Modifier]
392− }
393− deriving (Eq, Ord, Show)
301+instance MonadTrans (DisplayRegion t) where
302+ lift = DisplayRegion . lift
394303
395−-- | Information about a mouse up event
396−data MouseUp = MouseUp
397− { _mouseUp_button :: Maybe V.Button
398− , _mouseUp_coordinates :: (Int, Int)
399− }
400− deriving (Eq, Ord, Show)
304+instance MFunctor (DisplayRegion t) where
305+ hoist f = DisplayRegion . hoist f . unDisplayRegion
401306
402−-- | Mouse scroll direction
403−data ScrollDirection = ScrollDirection_Up | ScrollDirection_Down
404− deriving (Eq, Ord, Show)
307+instance MonadNodeId m => MonadNodeId (DisplayRegion t m)
405308
406−-- | Produce an event that fires when the mouse wheel is scrolled
407−mouseScroll
309+-- | Run a 'DisplayRegion' action with a given 'Region'
310+runDisplayRegion
408311 :: (Reflex t, Monad m)
409− => VtyWidget t m (Event t ScrollDirection)
410−mouseScroll = do
411− up <- mouseDown V.BScrollUp
412− down <- mouseDown V.BScrollDown
413− return $ leftmost
414− [ ScrollDirection_Up <$ up
415− , ScrollDirection_Down <$ down
416− ]
312+ => Dynamic t Region
313+ -> DisplayRegion t m a
314+ -> m a
315+runDisplayRegion r = flip runReaderT r . unDisplayRegion
417316
418−-- | Type synonym for a key and modifier combination
419−type KeyCombo = (V.Key, [V.Modifier])
317+-- * Getting focus state
420318
421−-- | Emits an event that fires on a particular key press (without modifiers)
422−key :: (Monad m, Reflex t) => V.Key -> VtyWidget t m (Event t KeyCombo)
423−key = keyCombos . Set.singleton . (,[])
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+ )
424347
425−-- | Emits an event that fires on particular key presses (without modifiers)
426−keys :: (Monad m, Reflex t) => [V.Key] -> VtyWidget t m (Event t KeyCombo)
427−keys = keyCombos . Set.fromList . fmap (,[])
348+instance (Monad m, Reflex t) => HasFocusReader t (FocusReader t m) where
349+ focus = FocusReader ask
350+ localFocus f = FocusReader . local f . unFocusReader
428351
429−-- | Emit an event that fires whenever the provided key combination occurs
430−keyCombo
431− :: (Reflex t, Monad m)
432− => KeyCombo
433− -> VtyWidget t m (Event t KeyCombo)
434−keyCombo = keyCombos . Set.singleton
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)
435358
436−-- | Emit an event that fires whenever any of the provided key combinations occur
437−keyCombos
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
438375 :: (Reflex t, Monad m)
439− => Set KeyCombo
440− -> VtyWidget t m (Event t KeyCombo)
441−keyCombos ks = do
442− i <- input
443− return $ fforMaybe i $ \case
444− V.EvKey k m -> if Set.member (k, m) ks
445− then Just (k, m)
446− else Nothing
447− _ -> Nothing
376+ => Dynamic t Bool
377+ -> FocusReader t m a
378+ -> m a
379+runFocusReader b = flip runReaderT b . unFocusReader
448380
449−-- | A plain split of the available space into vertically stacked panes.
450−-- No visual separator is built in here.
451−splitV :: (Reflex t, Monad m, MonadNodeId m)
452− => Dynamic t (Int -> Int)
453− -- ^ Function used to determine size of first pane based on available size
454− -> Dynamic t (Bool, Bool)
455− -- ^ How to focus the two sub-panes, given that we are focused.
456− -> VtyWidget t m a
457− -- ^ Widget for first pane
458− -> VtyWidget t m b
459− -- ^ Widget for second pane
460− -> VtyWidget t m (a,b)
461−splitV sizeFunD focD wA wB = do
462− dw <- displayWidth
463− dh <- displayHeight
464− let regA = DynRegion
465− { _dynRegion_left = pure 0
466− , _dynRegion_top = pure 0
467− , _dynRegion_width = dw
468− , _dynRegion_height = sizeFunD <*> dh
469− }
470− regB = DynRegion
471− { _dynRegion_left = pure 0
472− , _dynRegion_top = _dynRegion_height regA
473− , _dynRegion_width = dw
474− , _dynRegion_height = liftA2 (-) dh (_dynRegion_height regA)
475− }
476− ra <- pane regA (fst <$> focD) wA
477− rb <- pane regB (snd <$> focD) wB
478− return (ra,rb)
479−
480−-- | A plain split of the available space into horizontally stacked panes.
481−-- No visual separator is built in here.
482−splitH :: (Reflex t, Monad m, MonadNodeId m)
483− => Dynamic t (Int -> Int)
484− -- ^ Function used to determine size of first pane based on available size
485− -> Dynamic t (Bool, Bool)
486− -- ^ How to focus the two sub-panes, given that we are focused.
487− -> VtyWidget t m a
488− -- ^ Widget for first pane
489− -> VtyWidget t m b
490− -- ^ Widget for second pane
491− -> VtyWidget t m (a,b)
492−splitH sizeFunD focD wA wB = do
493− dw <- displayWidth
494− dh <- displayHeight
495− let regA = DynRegion
496− { _dynRegion_left = pure 0
497− , _dynRegion_top = pure 0
498− , _dynRegion_width = sizeFunD <*> dw
499− , _dynRegion_height = dh
500− }
501− regB = DynRegion
502− { _dynRegion_left = _dynRegion_width regA
503− , _dynRegion_top = pure 0
504− , _dynRegion_width = liftA2 (-) dw (_dynRegion_width regA)
505− , _dynRegion_height = dh
506− }
507− liftA2 (,) (pane regA (fmap fst focD) wA) (pane regB (fmap snd focD) wB)
508−
509−-- | A split of the available space into two parts with a draggable separator.
510−-- Starts with half the space allocated to each, and the first pane has focus.
511−-- Clicking in a pane switches focus.
512−splitVDrag :: (Reflex t, MonadFix m, MonadHold t m, MonadNodeId m)
513− => VtyWidget t m ()
514− -> VtyWidget t m a
515− -> VtyWidget t m b
516− -> VtyWidget t m (a,b)
517−splitVDrag wS wA wB = do
518− dh <- displayHeight
519− dw <- displayWidth
520− h0 <- sample $ current dh -- TODO
521− dragE <- drag V.BLeft
522− let splitter0 = h0 `div` 2
523− rec splitterCheckpoint <- holdDyn splitter0 $ leftmost [fst <$> ffilter snd dragSplitter, resizeSplitter]
524− splitterPos <- holdDyn splitter0 $ leftmost [fst <$> dragSplitter, resizeSplitter]
525− splitterFrac <- holdDyn ((1::Double) / 2) $ ffor (attach (current dh) (fst <$> dragSplitter)) $ \(h, x) ->
526− fromIntegral x / max 1 (fromIntegral h)
527− let dragSplitter = fforMaybe (attach (current splitterCheckpoint) dragE) $
528− \(splitterY, Drag (_, fromY) (_, toY) _ _ end) ->
529− if splitterY == fromY then Just (toY, end) else Nothing
530− regA = DynRegion 0 0 dw splitterPos
531− regS = DynRegion 0 splitterPos dw 1
532− regB = DynRegion 0 (splitterPos + 1) dw (dh - splitterPos - 1)
533− resizeSplitter = ffor (attach (current splitterFrac) (updated dh)) $
534− \(frac, h) -> round (frac * fromIntegral h)
535− focA <- holdDyn True $ leftmost
536− [ True <$ mA
537− , False <$ mB
538− ]
539− (mA, rA) <- pane regA focA $ withMouseDown wA
540− pane regS (pure False) wS
541− (mB, rB) <- pane regB (not <$> focA) $ withMouseDown wB
542− return (rA, rB)
543− where
544− withMouseDown x = do
545− m <- mouseDown V.BLeft
546− x' <- x
547− return (m, x')
548−
549−-- | Fill the background with a particular character.
550−fill :: (Reflex t, Monad m) => Char -> VtyWidget t m ()
551−fill c = do
552− dw <- displayWidth
553− dh <- displayHeight
554− let fillImg = current $ liftA2 (\w h -> [V.charFill V.defAttr c w h]) dw dh
555− tellImages fillImg
556−
557−-- | Fill the background with the bottom
558−hRule :: (Reflex t, Monad m) => BoxStyle -> VtyWidget t m ()
559−hRule boxStyle = fill (_boxStyle_s boxStyle)
560−
561−-- | Defines a set of symbols to use to draw the outlines of boxes
562−-- C.f. https://en.wikipedia.org/wiki/Box-drawing_character
563−data BoxStyle = BoxStyle
564− { _boxStyle_nw :: Char
565− , _boxStyle_n :: Char
566− , _boxStyle_ne :: Char
567− , _boxStyle_e :: Char
568− , _boxStyle_se :: Char
569− , _boxStyle_s :: Char
570− , _boxStyle_sw :: Char
571− , _boxStyle_w :: Char
572− }
381+-- * "Image" output
573382
574−instance Default BoxStyle where
575− def = singleBoxStyle
576−
577−-- | A box style that uses hyphens and pipe characters. Doesn't handle
578−-- corners very well.
579−hyphenBoxStyle :: BoxStyle
580−hyphenBoxStyle = BoxStyle '-' '-' '-' '|' '-' '-' '-' '|'
581−
582−-- | A single line box style
583−singleBoxStyle :: BoxStyle
584−singleBoxStyle = BoxStyle '┌' '─' '┐' '│' '┘' '─' '└' '│'
585−
586−-- | A thick single line box style
587−thickBoxStyle :: BoxStyle
588−thickBoxStyle = BoxStyle '┏' '━' '┓' '┃' '┛' '━' '┗' '┃'
589−
590−-- | A double line box style
591−doubleBoxStyle :: BoxStyle
592−doubleBoxStyle = BoxStyle '╔' '═' '╗' '║' '╝' '═' '╚' '║'
593−
594−-- | A single line box style with rounded corners
595−roundedBoxStyle :: BoxStyle
596−roundedBoxStyle = BoxStyle '╭' '─' '╮' '│' '╯' '─' '╰' '│'
597−
598−-- | Draws a titled box in the provided style and a child widget inside of that box
599−boxTitle :: (Monad m, Reflex t, MonadNodeId m)
600− => Behavior t BoxStyle
601− -> Text
602− -> VtyWidget t m a
603− -> VtyWidget t m a
604−boxTitle boxStyle title child = do
605− dh <- displayHeight
606− dw <- displayWidth
607− let boxReg = DynRegion (pure 0) (pure 0) dw dh
608− innerReg = DynRegion (pure 1) (pure 1) (subtract 2 <$> dw) (subtract 2 <$> dh)
609− tellImages (boxImages <$> boxStyle <*> currentRegion boxReg)
610− tellImages (fmap (\r -> [regionBlankImage r]) (currentRegion innerReg))
611− pane innerReg (pure True) child
612− where
613− boxImages :: BoxStyle -> Region -> [Image]
614− boxImages style (Region left top width height) =
615− let right = left + width - 1
616− bottom = top + height - 1
617− sides =
618− [ withinImage (Region (left + 1) top (width - 2) 1) $
619− V.text' V.defAttr $
620− hPadText title (_boxStyle_n style) (width - 2)
621− , withinImage (Region right (top + 1) 1 (height - 2)) $
622− V.charFill V.defAttr (_boxStyle_e style) 1 (height - 2)
623− , withinImage (Region (left + 1) bottom (width - 2) 1) $
624− V.charFill V.defAttr (_boxStyle_s style) (width - 2) 1
625− , withinImage (Region left (top + 1) 1 (height - 2)) $
626− V.charFill V.defAttr (_boxStyle_w style) 1 (height - 2)
627− ]
628− corners =
629− [ withinImage (Region left top 1 1) $
630− V.char V.defAttr (_boxStyle_nw style)
631− , withinImage (Region right top 1 1) $
632− V.char V.defAttr (_boxStyle_ne style)
633− , withinImage (Region right bottom 1 1) $
634− V.char V.defAttr (_boxStyle_se style)
635− , withinImage (Region left bottom 1 1) $
636− V.char V.defAttr (_boxStyle_sw style)
637− ]
638− in sides ++ if width > 1 && height > 1 then corners else []
639− hPadText :: T.Text -> Char -> Int -> T.Text
640− hPadText t c l = if lt >= l
641− then t
642− else left <> t <> right
643− where
644− lt = T.length t
645− delta = l - lt
646− mkHalf n = T.replicate (n `div` 2) (T.singleton c)
647− left = mkHalf $ delta + 1
648− right = mkHalf delta
649−
650−-- | A box without a title
651−box :: (Monad m, Reflex t, MonadNodeId m)
652− => Behavior t BoxStyle
653− -> VtyWidget t m a
654− -> VtyWidget t m a
655−box boxStyle = boxTitle boxStyle mempty
656−
657−-- | A box whose style is static
658−boxStatic
659− :: (Reflex t, Monad m, MonadNodeId m)
660− => BoxStyle
661− -> VtyWidget t m a
662− -> VtyWidget t m a
663−boxStatic = box . pure
664−
665−-- | Configuration options for displaying "rich" text
666−data RichTextConfig t = RichTextConfig
667− { _richTextConfig_attributes :: Behavior t V.Attr
668− }
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
669424
670−instance Reflex t => Default (RichTextConfig t) where
671− def = RichTextConfig $ pure V.defAttr
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)
672430
673−-- | A widget that displays text with custom time-varying attributes
674−richText
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
675443 :: (Reflex t, Monad m)
676− => RichTextConfig t
677− -> Behavior t Text
678− -> VtyWidget t m ()
679−richText cfg t = do
680− dw <- displayWidth
681− let img = (\w a s -> [wrapText w a s])
682− <$> current dw
683− <*> _richTextConfig_attributes cfg
684− <*> t
685− tellImages img
686− where
687− wrapText maxWidth attrs = V.vertCat
688− . concatMap (fmap (V.string attrs . T.unpack) . TZ.wrapWithOffset maxWidth 0)
689− . T.split (=='\n')
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
690502
691−-- | Renders text, wrapped to the container width
692−text
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
693510 :: (Reflex t, Monad m)
694− => Behavior t Text
695− -> VtyWidget t m ()
696−text = richText def
697−
698−-- | Scrollable text widget. The output pair exposes the current scroll position and total number of lines (including those
699−-- that are hidden)
700−scrollableText
701− :: forall t m. (Reflex t, MonadHold t m, MonadFix m)
702− => Event t Int
703− -- ^ Number of lines to scroll by
704− -> Behavior t Text
705− -> VtyWidget t m (Behavior t (Int, Int))
706− -- ^ (Current scroll position, total number of lines)
707−scrollableText scrollBy t = do
708− dw <- displayWidth
709− let imgs = wrap <$> current dw <*> t
710− kup <- key V.KUp
711− kdown <- key V.KDown
712− m <- mouseScroll
713− let requestedScroll :: Event t Int
714− requestedScroll = leftmost
715− [ 1 <$ kdown
716− , (-1) <$ kup
717− , ffor m $ \case
718− ScrollDirection_Up -> (-1)
719− ScrollDirection_Down -> 1
720− , scrollBy
721− ]
722− updateLine maxN delta ix = min (max 0 (ix + delta)) maxN
723− lineIndex :: Dynamic t Int <- foldDyn (\(maxN, delta) ix -> updateLine (maxN - 1) delta ix) 0 $
724− attach (length <$> imgs) requestedScroll
725− tellImages $ fmap ((:[]) . V.vertCat) $ drop <$> current lineIndex <*> imgs
726− return $ (,) <$> ((+) <$> current lineIndex <*> pure 1) <*> (length <$> imgs)
727− where
728− wrap maxWidth = concatMap (fmap (V.string V.defAttr . T.unpack) . TZ.wrapWithOffset maxWidth 0) . T.split (=='\n')
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
518+
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
528+
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
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
729556
730−-- | Renders any behavior whose value can be converted to
731−-- 'String' as text
732−display
733− :: (Reflex t, Monad m, Show a)
734− => Behavior t a
735− -> VtyWidget t m ()
736−display a = text $ T.pack . show <$> a
557+-- * Misc
737558
738559-- | A widget that draws nothing
739−blank :: Monad m => VtyWidget t m ()
560+blank :: Monad m => m ()
740561blank = return ()