@@ -2,153 +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 MultiParamTypeClasses #-}
13−{-# LANGUAGE OverloadedStrings #-}
14−{-# LANGUAGE RankNTypes #-}
15−{-# LANGUAGE RecursiveDo #-}
16−{-# LANGUAGE ScopedTypeVariables #-}
17−{-# LANGUAGE StandaloneDeriving #-}
18−{-# LANGUAGE TupleSections #-}
19−{-# LANGUAGE TypeFamilies #-}
20−{-# LANGUAGE UndecidableInstances #-}
21−
22−module Reflex.Vty.Widget
23− ( VtyWidgetCtx(..)
24− , VtyWidget(..)
25− , VtyWidgetOut(..)
26− , ImageWriter(..)
27− , runVtyWidget
28− , mainWidget
29− , mainWidgetWithHandle
30− , HasDisplaySize(..)
31− , HasFocus(..)
32− , HasVtyInput(..)
33− , DynRegion(..)
34− , currentRegion
35− , Region(..)
36− , regionSize
37− , regionBlankImage
38− , Drag(..)
39− , drag
40− , MouseDown(..)
41− , MouseUp(..)
42− , mouseDown
43− , mouseUp
44− , pane
45− , splitV
46− , splitVDrag
47− , box
48− , boxStatic
49− , RichTextConfig(..)
50− , richText
51− , text
52− , display
53− , BoxStyle(..)
54− , hyphenBoxStyle
55− , singleBoxStyle
56− , roundedBoxStyle
57− , thickBoxStyle
58− , doubleBoxStyle
59− , fill
60− , hRule
61− , KeyCombo
62− , key
63− , keys
64− , keyCombos
65− , SizedWidget
66− , StackT
67− , StackConfig(..)
68− , StackWidget(..)
69− , stack
70− , Direction(..)
71− , askDirection
72− , askRemainingSpace
73− , askOffset
74− , col
75− , row
76− , fixed
77− , fraction
78− , remaining
79− , tile
80− ) where
5+{-# Language UndecidableInstances #-}
6+
7+module Reflex.Vty.Widget where
818
829import Control.Applicative (liftA2)
83−import Control.Monad.TimeMachine
8410import Control.Monad.Fix (MonadFix)
85−import Control.Monad.Trans.Class
86−import Control.Monad.Trans (lift)
87−import Control.Monad.Reader
88−import Data.Default (Default(..))
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)
8917import Data.Set (Set)
9018import qualified Data.Set as Set
91−import Data.Text (Text)
92−import qualified Data.Text as T
93−import qualified Data.Text.Zipper as TZ
9419import Graphics.Vty (Image)
9520import qualified Graphics.Vty as V
9621import Reflex
9722import Reflex.Class ()
98−import Reflex.Class.Orphans ()
99−import Reflex.NotReady.Class
100−import Reflex.NotReady.Class.Orphans ()
101−
23+import Reflex.Host.Class (MonadReflexCreateTrigger)
10224import Reflex.Vty.Host
10325
104−-- | The context within which a 'VtyWidget' runs
105−data VtyWidgetCtx t = VtyWidgetCtx
106− { _vtyWidgetCtx_width :: Dynamic t Int
107− -- ^ The width of the region allocated to the widget.
108− , _vtyWidgetCtx_height :: Dynamic t Int
109− -- ^ The height of the region allocated to the widget.
110− , _vtyWidgetCtx_focus :: Dynamic t Bool
111− -- ^ Whether the widget should behave as if it has focus for keyboard input.
112− , _vtyWidgetCtx_input :: Event t VtyEvent
113− -- ^ User input events that the widget's parent chooses to share. These will generally
114− -- be filtered for relevance:
115− -- * Keyboard inputs are restricted to focused widgets
116− -- * Mouse inputs are restricted to the region in which the widget resides and are
117− -- translated into its internal coordinates.
118− }
119−
120−-- | The output of a 'VtyWidget'
121−data VtyWidgetOut t = VtyWidgetOut
122− { _vtyWidgetOut_shutdown :: Event t ()
123− }
124−
125−instance (Adjustable t m, MonadHold t m, Reflex t) => Adjustable t (VtyWidget t m) where
126− runWithReplace a0 a' = VtyWidget $ runWithReplace (unVtyWidget a0) $ fmap unVtyWidget a'
127− traverseIntMapWithKeyWithAdjust f dm0 dm' = VtyWidget $
128− traverseIntMapWithKeyWithAdjust (\k v -> unVtyWidget (f k v)) dm0 dm'
129− traverseDMapWithKeyWithAdjust f dm0 dm' = VtyWidget $ do
130− traverseDMapWithKeyWithAdjust (\k v -> unVtyWidget (f k v)) dm0 dm'
131− traverseDMapWithKeyWithAdjustWithMove f dm0 dm' = VtyWidget $ do
132− traverseDMapWithKeyWithAdjustWithMove (\k v -> unVtyWidget (f k v)) dm0 dm'
133−
134−-- | A widget that can read its context and produce image output
135−newtype VtyWidget t m a = VtyWidget
136− { unVtyWidget :: BehaviorWriterT t [Image] (ReaderT (VtyWidgetCtx t) m) a
137− }
138− deriving (Functor, Applicative, Monad, MonadSample t, MonadHold t, MonadFix, NotReady t, ImageWriter t, PostBuild t)
139−
140−-- | Runs a 'VtyWidget' with a given context
141−runVtyWidget
142− :: (Reflex t, Monad m)
143− => VtyWidgetCtx t
144− -> VtyWidget t m a
145− -> m (a, Behavior t [Image])
146−runVtyWidget ctx w = runReaderT (runBehaviorWriterT (unVtyWidget w)) ctx
26+-- * Running a vty application
14727
148−-- | 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
14929mainWidgetWithHandle
15030 :: V.Vty
151− -> (forall t m. MonadVtyApp t 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 ()))
15240 -> IO ()
15341mainWidgetWithHandle vty child =
15442 runVtyAppWithHandle vty $ \dr0 inp -> do
@@ -158,70 +46,178 @@ mainWidgetWithHandle vty child =
15846 let inp' = fforMaybe inp $ \case
15947 V.EvResize {} -> Nothing
16048 x -> Just x
161− let ctx = VtyWidgetCtx
162− { _vtyWidgetCtx_width = fmap fst size
163− , _vtyWidgetCtx_height = fmap snd size
164− , _vtyWidgetCtx_input = inp'
165− , _vtyWidgetCtx_focus = constDyn True
166− }
167− (shutdown, images) <- runVtyWidget ctx $ do
168− tellImages . ffor (current size) $ \(w, h) -> [V.charFill V.defAttr ' ' w h]
169− 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
17057 return $ VtyResult
17158 { _vtyResult_picture = fmap (V.picForLayers . reverse) images
17259 , _vtyResult_shutdown = shutdown
17360 }
17461
62+-- | The output of a vty widget
63+data VtyWidgetOut t = VtyWidgetOut
64+ { _vtyWidgetOut_shutdown :: Event t ()
65+ }
66+
17567-- | Like 'mainWidgetWithHandle', but uses a default vty configuration
17668mainWidget
177− :: (forall t m. MonadVtyApp t 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 ()))
17878 -> IO ()
17979mainWidget child = do
18080 vty <- getDefaultVty
18181 mainWidgetWithHandle vty child
18282
183−-- | A class for things that know their own display size dimensions
184−class (Reflex t, Monad m) => HasDisplaySize t m | m -> t where
185− -- | Retrieve the display width (columns)
186− displayWidth :: m (Dynamic t Int)
187− default displayWidth :: (f m' ~ m, MonadTrans f, HasDisplaySize t m') => m (Dynamic t Int)
188− displayWidth = lift displayWidth
189− -- | Retrieve the display height (rows)
190− displayHeight :: m (Dynamic t Int)
191− default displayHeight :: (f m' ~ m, MonadTrans f, HasDisplaySize t m') => m (Dynamic t Int)
192− displayHeight = lift displayHeight
193−instance (Reflex t, Monad m) => HasDisplaySize t (VtyWidget t m) where
194− displayWidth = VtyWidget . lift $ asks _vtyWidgetCtx_width
195− displayHeight = VtyWidget . lift $ asks _vtyWidgetCtx_height
196−
197−instance HasDisplaySize t m => HasDisplaySize t (ReaderT x m)
198−instance HasDisplaySize t m => HasDisplaySize t (BehaviorWriterT t x m)
199−instance HasDisplaySize t m => HasDisplaySize t (DynamicWriterT t x m)
200−instance HasDisplaySize t m => HasDisplaySize t (EventWriterT t x m)
201−
202−instance (MonadFix m, HasDisplaySize t m) => HasDisplaySize t (TimeMachineT back fwd m)
83+-- * Input Events
20384
20485-- | A class for things that can receive vty events as input
205−class HasVtyInput t m | m -> t where
86+class HasInput t m | m -> t where
20687 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+ )
207113
208−instance (Reflex t, Monad m) => HasVtyInput t (VtyWidget t m) where
209− 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
210149
211−-- | A class for things that can dynamically gain and lose focus
212−class HasFocus t m | m -> t where
213− focus :: m (Dynamic t Bool)
150+-- | Type synonym for a key and modifier combination
151+type KeyCombo = (V.Key, [V.Modifier])
214152
215−instance (Reflex t, Monad m) => HasFocus t (VtyWidget t m) where
216− 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 . (,[])
217156
218−-- | A class for widgets that can produce images to draw to the display
219−class (Reflex t, Monad m) => ImageWriter t m | m -> t where
220− -- | Send images upstream for rendering
221− 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 (,[])
222160
223−instance (Monad m, Reflex t) => ImageWriter t (BehaviorWriterT t [Image] m) where
224− 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
225221
226222-- | A chunk of the display area
227223data Region = Region
@@ -232,559 +228,334 @@ data Region = Region
232228 }
233229 deriving (Show, Read, Eq, Ord)
234230
235−-- | A dynamic chunk of the display area
236−data DynRegion t = DynRegion
237− { _dynRegion_left :: Dynamic t Int
238− , _dynRegion_top :: Dynamic t Int
239− , _dynRegion_width :: Dynamic t Int
240− , _dynRegion_height :: Dynamic t Int
241− }
231+-- | A region that occupies no space.
232+nilRegion :: Region
233+nilRegion = Region 0 0 0 0
242234
243235-- | The width and height of a 'Region'
244236regionSize :: Region -> (Int, Int)
245237regionSize (Region _ _ w h) = (w, h)
246238
247239-- | Produces an 'Image' that fills a region with space characters
248−regionBlankImage :: Region -> Image
249−regionBlankImage r@(Region _ _ width height) =
250− 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
251243
252−-- | A behavior of the current display area represented by a 'DynRegion'
253−currentRegion :: Reflex t => DynRegion t -> Behavior t Region
254−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+ )
255282
256−-- | Translates and crops an 'Image' so that it is contained by
257−-- the given 'Region'.
258−withinImage
259− :: Region
260− -> Image
261− -> Image
262−withinImage (Region left top width height)
263− | width < 0 || height < 0 = withinImage (Region left top 0 0)
264− | 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
265286
266−-- | Low-level widget combinator that runs a child 'VtyWidget' within
267−-- a given region and context. This widget filters and modifies the input
268−-- that the child widget receives such that:
269−-- * unfocused widgets receive no key events
270−-- * mouse inputs outside the region are ignored
271−-- * mouse inputs inside the region have their coordinates translated such
272−-- that (0,0) is the top-left corner of the region
273−pane
274− :: (Reflex t, Monad m)
275− => DynRegion t
276− -> Dynamic t Bool -- ^ Whether the widget should be focused when the parent is.
277− -> VtyWidget t m a
278− -> VtyWidget t m a
279−pane dr foc child = VtyWidget $ do
280− ctx <- lift ask
281− let reg = currentRegion dr
282− let ctx' = VtyWidgetCtx
283− { _vtyWidgetCtx_input = leftmost -- TODO: think about this leftmost more.
284− [ fmapMaybe id $
285− attachWith (\(r,f) e -> filterInput r f e)
286− (liftA2 (,) reg (current foc))
287− (_vtyWidgetCtx_input ctx)
288− ]
289− , _vtyWidgetCtx_focus = liftA2 (&&) (_vtyWidgetCtx_focus ctx) foc
290− , _vtyWidgetCtx_width = _dynRegion_width dr
291− , _vtyWidgetCtx_height = _dynRegion_height dr
292− }
293− (result, images) <- lift . lift $ runVtyWidget ctx' child
294− let images' = liftA2 (\r is -> map (withinImage r) is) reg images
295− tellImages images'
296− return result
297− where
298− filterInput :: Region -> Bool -> VtyEvent -> Maybe VtyEvent
299− filterInput (Region l t w h) focused e = case e of
300− V.EvKey _ _ | not focused -> Nothing
301− V.EvMouseDown x y btn m -> mouse (\u v -> V.EvMouseDown u v btn m) x y
302− V.EvMouseUp x y btn -> mouse (\u v -> V.EvMouseUp u v btn) x y
303− _ -> Just e
304− where
305− mouse con x y
306− | or [ x < l
307− , y < t
308− , x >= l + w
309− , y >= t + h ] = Nothing
310− | otherwise =
311− Just (con (x - l) (y - t))
312−
313−-- | Information about a drag operation
314−data Drag = Drag
315− { _drag_from :: (Int, Int) -- ^ Where the drag began
316− , _drag_to :: (Int, Int) -- ^ Where the mouse currently is
317− , _drag_button :: V.Button -- ^ Which mouse button is dragging
318− , _drag_modifiers :: [V.Modifier] -- ^ What modifiers are held
319− , _drag_end :: Bool -- ^ Whether the drag ended (the mouse button was released)
320− }
321− deriving (Eq, Ord, Show)
322−
323−-- | Converts raw vty mouse drag events into an event stream of 'Drag's
324−drag
325− :: (Reflex t, MonadFix m, MonadHold t m)
326− => V.Button
327− -> VtyWidget t m (Event t Drag)
328−drag btn = do
329− inp <- input
330− let f :: Maybe Drag -> V.Event -> Maybe Drag
331− f Nothing = \case
332− V.EvMouseDown x y btn' mods
333− | btn == btn' -> Just $ Drag (x,y) (x,y) btn' mods False
334− | otherwise -> Nothing
335− _ -> Nothing
336− f (Just (Drag from _ _ mods end)) = \case
337− V.EvMouseDown x y btn' mods'
338− | end -> Just $ Drag (x,y) (x,y) btn' mods' False
339− | btn == btn' -> Just $ Drag from (x,y) btn mods' False
340− | otherwise -> Nothing -- Ignore other buttons.
341− V.EvMouseUp x y (Just btn')
342− | end -> Nothing
343− | btn == btn' -> Just $ Drag from (x,y) btn mods True
344− | otherwise -> Nothing
345− V.EvMouseUp x y Nothing -- Terminal doesn't specify mouse up button,
346− -- assume it's the right one.
347− | end -> Nothing
348− | otherwise -> Just $ Drag from (x,y) btn mods True
349− _ -> Nothing
350− rec let newDrag = attachWithMaybe f (current dragD) inp
351− dragD <- holdDyn Nothing $ Just <$> newDrag
352− return (fmapMaybe id $ updated dragD)
353−
354−-- | Mouse down events for a particular mouse button
355−mouseDown
356− :: (Reflex t, Monad m)
357− => V.Button
358− -> VtyWidget t m (Event t MouseDown)
359−mouseDown btn = do
360− i <- input
361− return $ fforMaybe i $ \case
362− V.EvMouseDown x y btn' mods -> if btn == btn'
363− then Just $ MouseDown btn' (x, y) mods
364− else Nothing
365− _ -> 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)
366294
367−-- | Mouse up events for a particular mouse button
368−mouseUp
369− :: (Reflex t, Monad m)
370− => VtyWidget t m (Event t MouseUp)
371−mouseUp = do
372− i <- input
373− return $ fforMaybe i $ \case
374− V.EvMouseUp x y btn' -> Just $ MouseUp btn' (x, y)
375− _ -> 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
376300
377−-- | Information about a mouse down event
378−data MouseDown = MouseDown
379− { _mouseDown_button :: V.Button
380− , _mouseDown_coordinates :: (Int, Int)
381− , _mouseDown_modifiers :: [V.Modifier]
382− }
383− deriving (Eq, Ord, Show)
301+instance MonadTrans (DisplayRegion t) where
302+ lift = DisplayRegion . lift
384303
385−-- | Information about a mouse up event
386−data MouseUp = MouseUp
387− { _mouseUp_button :: Maybe V.Button
388− , _mouseUp_coordinates :: (Int, Int)
389− }
390− deriving (Eq, Ord, Show)
304+instance MFunctor (DisplayRegion t) where
305+ hoist f = DisplayRegion . hoist f . unDisplayRegion
391306
392−-- | Type synonym for a key and modifier combination
393−type KeyCombo = (V.Key, [V.Modifier])
307+instance MonadNodeId m => MonadNodeId (DisplayRegion t m)
394308
395−-- | Emits an event that fires on a particular key press (without modifiers)
396−key :: (Monad m, Reflex t) => V.Key -> VtyWidget t m (Event t KeyCombo)
397−key = keyCombos . Set.singleton . (,[])
309+-- | Run a 'DisplayRegion' action with a given 'Region'
310+runDisplayRegion
311+ :: (Reflex t, Monad m)
312+ => Dynamic t Region
313+ -> DisplayRegion t m a
314+ -> m a
315+runDisplayRegion r = flip runReaderT r . unDisplayRegion
398316
399−-- | Emits an event that fires on particular key presses (without modifiers)
400−keys :: (Monad m, Reflex t) => [V.Key] -> VtyWidget t m (Event t KeyCombo)
401−keys = keyCombos . Set.fromList . fmap (,[])
317+-- * Getting focus state
402318
403−-- | Emit an event that fires whenever any of the provided key combinations occur
404−keyCombos
405− :: (Reflex t, Monad m)
406− => Set KeyCombo
407− -> VtyWidget t m (Event t KeyCombo)
408−keyCombos ks = do
409− i <- input
410− return $ fforMaybe i $ \case
411− V.EvKey k m -> if Set.member (k, m) ks
412− then Just (k, m)
413− else Nothing
414− _ -> Nothing
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+ )
415347
416−-- | A plain split of the available space into vertically stacked panes.
417−-- No visual separator is built in here.
418−splitV :: (Reflex t, Monad m)
419− => Dynamic t (Int -> Int)
420− -- ^ Function used to determine size of first pane based on available size
421− -> Dynamic t (Bool, Bool)
422− -- ^ How to focus the two sub-panes, given that we are focused.
423− -> VtyWidget t m a
424− -- ^ Widget for first pane
425− -> VtyWidget t m b
426− -- ^ Widget for second pane
427− -> VtyWidget t m (a,b)
428−splitV sizeFunD focD wA wB = do
429− dw <- displayWidth
430− dh <- displayHeight
431− let regA = DynRegion
432− { _dynRegion_left = pure 0
433− , _dynRegion_top = pure 0
434− , _dynRegion_width = dw
435− , _dynRegion_height = sizeFunD <*> dh
436− }
437− regB = DynRegion
438− { _dynRegion_left = pure 0
439− , _dynRegion_top = _dynRegion_height regA
440− , _dynRegion_width = dw
441− , _dynRegion_height = liftA2 (-) dh (_dynRegion_height regA)
442− }
443− ra <- pane regA (fst <$> focD) wA
444− rb <- pane regB (snd <$> focD) wB
445− return (ra,rb)
446−
447−-- | A split of the available space into two parts with a draggable separator.
448−-- Starts with half the space allocated to each, and the first pane has focus.
449−-- Clicking in a pane switches focus.
450−splitVDrag :: (Reflex t, MonadFix m, MonadHold t m)
451− => VtyWidget t m ()
452− -> VtyWidget t m a
453− -> VtyWidget t m b
454− -> VtyWidget t m (a,b)
455−splitVDrag wS wA wB = do
456− dh <- displayHeight
457− dw <- displayWidth
458− h0 <- sample $ current dh -- TODO
459− dragE <- drag V.BLeft
460− let splitter0 = h0 `div` 2
461− rec splitterCheckpoint <- holdDyn splitter0 $ leftmost [fst <$> ffilter snd dragSplitter, resizeSplitter]
462− splitterPos <- holdDyn splitter0 $ leftmost [fst <$> dragSplitter, resizeSplitter]
463− splitterFrac <- holdDyn ((1::Double) / 2) $ ffor (attach (current dh) (fst <$> dragSplitter)) $ \(h, x) ->
464− fromIntegral x / fromIntegral h
465− let dragSplitter = fforMaybe (attach (current splitterCheckpoint) dragE) $
466− \(splitterY, Drag (_, fromY) (_, toY) _ _ end) ->
467− if splitterY == fromY then Just (toY, end) else Nothing
468− regA = DynRegion 0 0 dw splitterPos
469− regS = DynRegion 0 splitterPos dw 1
470− regB = DynRegion 0 (splitterPos + 1) dw (dh - splitterPos - 1)
471− resizeSplitter = ffor (attach (current splitterFrac) (updated dh)) $
472− \(frac, h) -> round (frac * fromIntegral h)
473− focA <- holdDyn True $ leftmost
474− [ True <$ mA
475− , False <$ mB
476− ]
477− (mA, rA) <- pane regA focA $ withMouseDown wA
478− pane regS (pure False) wS
479− (mB, rB) <- pane regB (not <$> focA) $ withMouseDown wB
480− return (rA, rB)
481− where
482− withMouseDown x = do
483− m <- mouseDown V.BLeft
484− x' <- x
485− return (m, x')
486−
487−-- | Fill the background with a particular character.
488−fill :: (Reflex t, Monad m) => Char -> VtyWidget t m ()
489−fill c = do
490− dw <- displayWidth
491− dh <- displayHeight
492− let fillImg = current $ liftA2 (\w h -> [V.charFill V.defAttr c w h]) dw dh
493− tellImages fillImg
494−
495−-- | Fill the background with the bottom
496−hRule :: (Reflex t, Monad m) => BoxStyle -> VtyWidget t m ()
497−hRule boxStyle = fill (_boxStyle_s boxStyle)
498−
499−-- | Defines a set of symbols to use to draw the outlines of boxes
500−-- C.f. https://en.wikipedia.org/wiki/Box-drawing_character
501−data BoxStyle = BoxStyle
502− { _boxStyle_nw :: Char
503− , _boxStyle_n :: Char
504− , _boxStyle_ne :: Char
505− , _boxStyle_e :: Char
506− , _boxStyle_se :: Char
507− , _boxStyle_s :: Char
508− , _boxStyle_sw :: Char
509− , _boxStyle_w :: Char
510− }
348+instance (Monad m, Reflex t) => HasFocusReader t (FocusReader t m) where
349+ focus = FocusReader ask
350+ localFocus f = FocusReader . local f . unFocusReader
511351
512−instance Default BoxStyle where
513− def = singleBoxStyle
514−
515−-- | A box style that uses hyphens and pipe characters. Doesn't handle
516−-- corners very well.
517−hyphenBoxStyle :: BoxStyle
518−hyphenBoxStyle = BoxStyle '-' '-' '-' '|' '-' '-' '-' '|'
519−
520−-- | A single line box style
521−singleBoxStyle :: BoxStyle
522−singleBoxStyle = BoxStyle '┌' '─' '┐' '│' '┘' '─' '└' '│'
523−
524−-- | A thick single line box style
525−thickBoxStyle :: BoxStyle
526−thickBoxStyle = BoxStyle '┏' '━' '┓' '┃' '┛' '━' '┗' '┃'
527−
528−-- | A double line box style
529−doubleBoxStyle :: BoxStyle
530−doubleBoxStyle = BoxStyle '╔' '═' '╗' '║' '╝' '═' '╚' '║'
531−
532−-- | A single line box style with rounded corners
533−roundedBoxStyle :: BoxStyle
534−roundedBoxStyle = BoxStyle '╭' '─' '╮' '│' '╯' '─' '╰' '│'
535−
536−-- | Draws a box in the provided style and a child widget inside of that box
537−box :: (Monad m, Reflex t)
538− => Behavior t BoxStyle
539− -> VtyWidget t m a
540− -> VtyWidget t m a
541−box boxStyle child = do
542− dh <- displayHeight
543− dw <- displayWidth
544− let boxReg = DynRegion (pure 0) (pure 0) dw dh
545− innerReg = DynRegion (pure 1) (pure 1) (subtract 2 <$> dw) (subtract 2 <$> dh)
546− tellImages (boxImages <$> boxStyle <*> currentRegion boxReg)
547− tellImages (fmap (\r -> [regionBlankImage r]) (currentRegion innerReg))
548− pane innerReg (pure True) child
549− where
550− boxImages :: BoxStyle -> Region -> [Image]
551− boxImages style (Region left top width height) =
552− let right = left + width - 1
553− bottom = top + height - 1
554− sides =
555− [ withinImage (Region (left + 1) top (width - 2) 1) $
556− V.charFill V.defAttr (_boxStyle_n style) (width - 2) 1
557− , withinImage (Region right (top + 1) 1 (height - 2)) $
558− V.charFill V.defAttr (_boxStyle_e style) 1 (height - 2)
559− , withinImage (Region (left + 1) bottom (width - 2) 1) $
560− V.charFill V.defAttr (_boxStyle_s style) (width - 2) 1
561− , withinImage (Region left (top + 1) 1 (height - 2)) $
562− V.charFill V.defAttr (_boxStyle_w style) 1 (height - 2)
563− ]
564− corners =
565− [ withinImage (Region left top 1 1) $
566− V.char V.defAttr (_boxStyle_nw style)
567− , withinImage (Region right top 1 1) $
568− V.char V.defAttr (_boxStyle_ne style)
569− , withinImage (Region right bottom 1 1) $
570− V.char V.defAttr (_boxStyle_se style)
571− , withinImage (Region left bottom 1 1) $
572− V.char V.defAttr (_boxStyle_sw style)
573− ]
574− in sides ++ if width > 1 && height > 1 then corners else []
575−
576−-- | A box whose style is static
577−boxStatic
578− :: (Reflex t, Monad m)
579− => BoxStyle
580− -> VtyWidget t m a
581− -> VtyWidget t m a
582−boxStatic = box . pure
583−
584−-- | Configuration options for displaying "rich" text
585−data RichTextConfig t = RichTextConfig
586− { _richTextConfig_attributes :: Behavior t V.Attr
587− }
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)
588358
589−instance Reflex t => Default (RichTextConfig t) where
590− def = RichTextConfig $ pure V.defAttr
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
591364
592−-- | A widget that displays text with custom time-varying attributes
593−richText
594− :: (Reflex t, Monad m)
595− => RichTextConfig t
596− -> Behavior t Text
597− -> VtyWidget t m ()
598−richText cfg t = do
599− dw <- displayWidth
600− let img = (\w a s -> [wrapText w a s])
601− <$> current dw
602− <*> _richTextConfig_attributes cfg
603− <*> t
604− tellImages img
605− where
606− wrapText maxWidth attrs = V.vertCat
607− . concatMap (fmap (V.string attrs . T.unpack) . TZ.wrapWithOffset maxWidth 0)
608− . T.split (=='\n')
365+instance MonadTrans (FocusReader t) where
366+ lift = FocusReader . lift
367+
368+instance MFunctor (FocusReader t) where
369+ hoist f = FocusReader . hoist f . unFocusReader
609370
610−-- | Renders text, wrapped to the container width
611−text
371+instance MonadNodeId m => MonadNodeId (FocusReader t m)
372+
373+-- | Run a 'FocusReader' action with the given focus value
374+runFocusReader
612375 :: (Reflex t, Monad m)
613− => Behavior t Text
614− -> VtyWidget t m ()
615−text = richText def
616−
617−-- | Renders any behavior whose value can be converted to
618−-- 'String' as text
619−display
620− :: (Reflex t, Monad m, Show a)
621− => Behavior t a
622− -> VtyWidget t m ()
623−display a = text $ T.pack . show <$> a
624−
625−-- | The main-axis orientation of a 'StackWidget' widget
626−data Direction = Direction_Column
627− | Direction_Row
628− deriving (Show, Read, Eq, Ord)
376+ => Dynamic t Bool
377+ -> FocusReader t m a
378+ -> m a
379+runFocusReader b = flip runReaderT b . unFocusReader
380+
381+-- * "Image" output
629382
630−-- | Convenience type synonym for the 'TimeMachine' used to manage 'StackWidget'
631−-- focus and offset states. The first parameter is the "focus previous" event and
632−-- the second parameter is a tuple of "focus next" and the total size.
633−type StackT t = TimeMachineT (Event t ()) (Event t (), Dynamic t Int)
634−
635−-- | A 'VtyWidget' that can be stacked automatically
636−newtype StackWidget t m a
637− = StackWidget
638− { unStackWidget ::
639− StackT t
640− (EventWriterT t ()
641− (ReaderT (StackConfig, Event t ())
642− (VtyWidget t m))) a
643− }
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 }
644397 deriving
645398 ( Functor
646399 , Applicative
647400 , Monad
648− , MonadSample t
649− , MonadHold t
650401 , MonadFix
402+ , MonadHold t
403+ , MonadIO
404+ , MonadRef
405+ , MonadReflexCreateTrigger t
406+ , MonadSample t
651407 , NotReady t
652− , HasDisplaySize t
408+ , PerformEvent t
409+ , PostBuild t
410+ , TriggerEvent t
653411 )
654412
655−-- | Retrieve the 'Direction'/orientation of the current 'StackWidget'
656−askDirection :: MonadFix m => StackWidget t m Direction
657−askDirection = StackWidget $ asks $ _stackConfig_direction . fst
658−
659−-- | Retrieve the offset reported by the previous 'tile'
660−askOffset :: Monad m => StackWidget t m (Dynamic t Int)
661−askOffset = StackWidget $ snd <$> recvFromPast
662−
663−-- | Compute the remaining main-axis space available
664−askRemainingSpace :: (Reflex t, MonadFix m) => StackWidget t m (Dynamic t Int)
665−askRemainingSpace = do
666− dir <- askDirection
667− offset <- askOffset
668− sz <- case dir of
669− Direction_Column -> displayHeight
670− Direction_Row -> displayWidth
671− return $ sz - offset
672−
673−-- | A 'VtyWidget' and its actual main-axis size
674−type SizedWidget t m a = VtyWidget t m (Dynamic t Int, a)
675−
676−-- | Runs a 'StackWidget' with the provided configuration and initial offset
677−runStackWidget
678− :: (MonadFix m, PostBuild t m)
679− => StackConfig
680− -> Dynamic t Int
681− -> StackWidget t m a
682− -> SizedWidget t m a
683−runStackWidget cfg offset x = do
684− pb <- getPostBuild
685− rec ((back, (fwd, sz), a), unfocus) <- runReaderT (runEventWriterT (runTimeMachineT (unStackWidget x) back (fwd <> pb, offset))) (cfg, unfocus)
686− return (sz, a)
687−
688−-- | Turns a 'SizedWidget' into a 'StackWidget'. Wires up the focus-switching
689−-- and offset propagation.
690−tile
691− :: (Reflex t, MonadHold t m, MonadFix m)
692− => SizedWidget t m a
693− -> StackWidget t m a
694−tile s = StackWidget $ do
695− (focusTriggerP, offset) <- recvFromPast
696− rec sendToPast focusBackward
697− (cfg, unfocus) <- ask
698− let bk = Set.difference (_stackConfig_focusPrevKey cfg) fk
699− fk = _stackConfig_focusNextKey cfg
700− focused <- holdDyn False $ leftmost
701− [ True <$ (focusTriggerF <> focusTriggerP)
702− , True <$ click
703− , False <$ unfocus -- NB: unfocus must come after events that focus the current widget
704− ]
705− tellEvent $ mconcat
706− [ () <$ click
707− , () <$ keypress
708− ]
709− reg <- case _stackConfig_direction cfg of
710− Direction_Column -> do
711− w <- displayWidth
712− return $ DynRegion 0 offset w sz
713− Direction_Row -> do
714− h <- displayHeight
715− return $ DynRegion offset 0 sz h
716− (click, keypress, (sz, r)) <- lift $ lift $ lift $ pane reg focused $ do
717− e <- mouseDown V.BLeft
718− ek <- keyCombos $ Set.union bk fk
719− v <- s
720− return (e, ek, v)
721− let focusForward = () <$ ffilter (flip Set.member fk) keypress
722− focusBackward = () <$ ffilter (flip Set.member bk) keypress
723− focusTriggerF <- recvFromFuture
724− sendToFuture (focusForward, sz + offset)
725− return r
726−
727−-- | Configuration for a 'StackWidget'
728−data StackConfig = StackConfig
729− { _stackConfig_direction :: Direction
730− , _stackConfig_focusNextKey :: Set KeyCombo
731− , _stackConfig_focusPrevKey :: Set KeyCombo
732− }
413+instance MonadTrans (ImageWriter t) where
414+ lift = ImageWriter . lift
733415
734−instance Default StackConfig where
735− def = StackConfig
736− { _stackConfig_direction = Direction_Column
737− , _stackConfig_focusNextKey = Set.singleton (V.KChar '\t', [])
738− , _stackConfig_focusPrevKey = Set.singleton (V.KBackTab, [])
739− }
740−
741−-- | Runs a 'StackWidget' with the provided configuration
742−stack
743− :: (MonadFix m, PostBuild t m)
744− => StackConfig
745− -> StackWidget t m a
746− -> VtyWidget t m a
747−stack cfg w = fmap snd $ runStackWidget cfg 0 w
748−
749−-- | Runs a vertically-oriented 'StackWidget' (i.e., a column)
750−col
751− :: (MonadFix m, PostBuild t m)
752− => StackWidget t m a
753− -> VtyWidget t m a
754−col = stack def
755−
756−-- | Runs a horizontally-oriented 'StackWidget' (i.e., a row)
757−row
758− :: (MonadFix m, PostBuild t m)
759− => StackWidget t m a
760− -> VtyWidget t m a
761−row = stack $ def { _stackConfig_direction = Direction_Row }
762−
763−-- | A 'tile' of a fixed size
764−fixed
765− :: (Reflex t, MonadFix m, MonadHold t m)
766− => Dynamic t Int
767− -> VtyWidget t m a
768− -> StackWidget t m a
769−fixed sz w = tile $ (sz,) <$> w
770−
771−-- | A 'tile' that takes up the given fraction of the remaining
772−-- main-axis space
773−fraction
774− :: (Reflex t, MonadFix m, MonadHold t m)
775− => Dynamic t Rational
776− -> VtyWidget t m a
777− -> StackWidget t m a
778−fraction n w = do
779− s <- askRemainingSpace
780− let sz = fmap round $ n * fmap fromIntegral s
781− fixed sz w
782−
783−-- | A 'tile' that takes up all of the remaining main-axis space
784−remaining
785− :: (Reflex t, MonadHold t m, MonadFix m)
786− => VtyWidget t m a
787− -> StackWidget t m a
788−remaining w = do
789− s <- askRemainingSpace
790− fixed s w
416+instance MFunctor (ImageWriter t) where
417+ hoist f = ImageWriter . (hoist f) . unImageWriter
418+
419+instance (Adjustable t m, MonadFix m, MonadHold t m) => Adjustable t (ImageWriter t m) where
420+ runWithReplace (ImageWriter a) e = ImageWriter $ runWithReplace a $ fmap unImageWriter e
421+ traverseIntMapWithKeyWithAdjust f m e = ImageWriter $ traverseIntMapWithKeyWithAdjust (\k v -> unImageWriter $ f k v) m e
422+ traverseDMapWithKeyWithAdjust f m e = ImageWriter $ traverseDMapWithKeyWithAdjust (\k v -> unImageWriter $ f k v) m e
423+ traverseDMapWithKeyWithAdjustWithMove f m e = ImageWriter $ traverseDMapWithKeyWithAdjustWithMove (\k v -> unImageWriter $ f k v) m e
424+
425+instance HasImageWriter t m => HasImageWriter t (ReaderT x m)
426+instance HasImageWriter t m => HasImageWriter t (BehaviorWriterT t x m)
427+instance HasImageWriter t m => HasImageWriter t (DynamicWriterT t x m)
428+instance HasImageWriter t m => HasImageWriter t (EventWriterT t x m)
429+instance HasImageWriter t m => HasImageWriter t (NodeIdT m)
430+
431+instance (Monad m, Reflex t) => HasImageWriter t (ImageWriter t m) where
432+ tellImages = ImageWriter . tellBehavior
433+ mapImages f (ImageWriter x) = ImageWriter $ do
434+ (a, images) <- lift $ runBehaviorWriterT x
435+ tellBehavior $ f images
436+ pure a
437+
438+instance HasDisplayRegion t m => HasDisplayRegion t (ImageWriter t m)
439+instance HasFocusReader t m => HasFocusReader t (ImageWriter t m)
440+
441+-- | Run a widget that can produce images
442+runImageWriter
443+ :: (Reflex t, Monad m)
444+ => ImageWriter t m a
445+ -> m (a, Behavior t [Image])
446+runImageWriter = runBehaviorWriterT . unImageWriter
447+
448+-- * Theming
449+
450+-- | A class for things that can be visually styled
451+class (Reflex t, Monad m) => HasTheme t m | m -> t where
452+ theme :: m (Behavior t V.Attr)
453+ default theme :: (f m' ~ m, Monad m', MonadTrans f, HasTheme t m') => m (Behavior t V.Attr)
454+ theme = lift theme
455+ localTheme :: (Behavior t V.Attr -> Behavior t V.Attr) -> m a -> m a
456+ default localTheme :: (f m' ~ m, Monad m', MFunctor f, HasTheme t m') => (Behavior t V.Attr -> Behavior t V.Attr) -> m a -> m a
457+ localTheme f = hoist (localTheme f)
458+
459+instance HasTheme t m => HasTheme t (ReaderT x m)
460+instance HasTheme t m => HasTheme t (BehaviorWriterT t x m)
461+instance HasTheme t m => HasTheme t (DynamicWriterT t x m)
462+instance HasTheme t m => HasTheme t (EventWriterT t x m)
463+instance HasTheme t m => HasTheme t (NodeIdT m)
464+instance HasTheme t m => HasTheme t (Input t m)
465+instance HasTheme t m => HasTheme t (ImageWriter t m)
466+instance HasTheme t m => HasTheme t (DisplayRegion t m)
467+instance HasTheme t m => HasTheme t (FocusReader t m)
468+
469+-- | A widget that has access to theme information
470+newtype ThemeReader t m a = ThemeReader
471+ { unThemeReader :: ReaderT (Behavior t V.Attr) m a }
472+ deriving
473+ ( Functor
474+ , Applicative
475+ , Monad
476+ , MonadFix
477+ , MonadHold t
478+ , MonadIO
479+ , MonadRef
480+ , MonadSample t
481+ )
482+
483+instance (Monad m, Reflex t) => HasTheme t (ThemeReader t m) where
484+ theme = ThemeReader ask
485+ localTheme f = ThemeReader . local f . unThemeReader
486+
487+deriving instance MonadReflexCreateTrigger t m => MonadReflexCreateTrigger t (ThemeReader t m)
488+deriving instance NotReady t m => NotReady t (ThemeReader t m)
489+deriving instance PerformEvent t m => PerformEvent t (ThemeReader t m)
490+deriving instance PostBuild t m => PostBuild t (ThemeReader t m)
491+deriving instance TriggerEvent t m => TriggerEvent t (ThemeReader t m)
492+instance HasImageWriter t m => HasImageWriter t (ThemeReader t m)
493+
494+instance (Adjustable t m, MonadFix m, MonadHold t m) => Adjustable t (ThemeReader t m) where
495+ runWithReplace (ThemeReader a) e = ThemeReader $ runWithReplace a $ fmap unThemeReader e
496+ traverseIntMapWithKeyWithAdjust f m e = ThemeReader $ traverseIntMapWithKeyWithAdjust (\k v -> unThemeReader $ f k v) m e
497+ traverseDMapWithKeyWithAdjust f m e = ThemeReader $ traverseDMapWithKeyWithAdjust (\k v -> unThemeReader $ f k v) m e
498+ traverseDMapWithKeyWithAdjustWithMove f m e = ThemeReader $ traverseDMapWithKeyWithAdjustWithMove (\k v -> unThemeReader $ f k v) m e
499+
500+instance MonadTrans (ThemeReader t) where
501+ lift = ThemeReader . lift
502+
503+instance MFunctor (ThemeReader t) where
504+ hoist f = ThemeReader . hoist f . unThemeReader
505+
506+instance MonadNodeId m => MonadNodeId (ThemeReader t m)
507+
508+-- | Run a 'ThemeReader' action with the given focus value
509+runThemeReader
510+ :: (Reflex t, Monad m)
511+ => Behavior t V.Attr
512+ -> ThemeReader t m a
513+ -> m a
514+runThemeReader b = flip runReaderT b . unThemeReader
515+
516+
517+-- ** Manipulating images
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
556+
557+-- * Misc
558+
559+-- | A widget that draws nothing
560+blank :: Monad m => m ()
561+blank = return ()