1use crate::{
2 px, AnyView, AppContext, AvailableSpace, Bounds, Context, Effect, Element, EntityId, Handle,
3 LayoutId, MainThreadOnly, Pixels, Platform, PlatformWindow, Point, Reference, Scene, Size,
4 Style, TaffyLayoutEngine, TextStyle, TextStyleRefinement, WeakHandle, WindowOptions,
5};
6use anyhow::Result;
7use collections::HashMap;
8use derive_more::{Deref, DerefMut};
9use refineable::Refineable;
10use std::{
11 any::{Any, TypeId},
12 future,
13 marker::PhantomData,
14 sync::Arc,
15};
16use util::ResultExt;
17
18pub struct AnyWindow {}
19
20pub struct Window {
21 handle: AnyWindowHandle,
22 platform_window: MainThreadOnly<Box<dyn PlatformWindow>>,
23 rem_size: Pixels,
24 content_size: Size<Pixels>,
25 layout_engine: TaffyLayoutEngine,
26 text_style_stack: Vec<TextStyleRefinement>,
27 state_stacks_by_type: HashMap<TypeId, Vec<Box<dyn Any + Send + Sync>>>,
28 pub(crate) root_view: Option<AnyView<()>>,
29 mouse_position: Point<Pixels>,
30 pub(crate) scene: Scene,
31 pub(crate) dirty: bool,
32}
33
34impl Window {
35 pub fn new(
36 handle: AnyWindowHandle,
37 options: WindowOptions,
38 platform: &dyn Platform,
39 cx: &mut AppContext,
40 ) -> Self {
41 let platform_window = platform.open_window(handle, options);
42 let mouse_position = platform_window.mouse_position();
43 let content_size = platform_window.content_size();
44 let scale_factor = platform_window.scale_factor();
45 platform_window.on_resize(Box::new({
46 let handle = handle;
47 let cx = cx.to_async();
48 move |content_size, scale_factor| {
49 cx.update_window(handle, |cx| {
50 cx.window.scene = Scene::new(scale_factor);
51 cx.window.content_size = content_size;
52 cx.window.dirty = true;
53 })
54 .log_err();
55 }
56 }));
57
58 let platform_window = MainThreadOnly::new(Arc::new(platform_window), platform.dispatcher());
59
60 Window {
61 handle,
62 platform_window,
63 rem_size: px(16.),
64 content_size,
65 layout_engine: TaffyLayoutEngine::new(),
66 text_style_stack: Vec::new(),
67 state_stacks_by_type: HashMap::default(),
68 root_view: None,
69 mouse_position,
70 scene: Scene::new(scale_factor),
71 dirty: true,
72 }
73 }
74}
75
76#[derive(Deref, DerefMut)]
77pub struct WindowContext<'a, 'b> {
78 #[deref]
79 #[deref_mut]
80 app: Reference<'a, AppContext>,
81 window: Reference<'b, Window>,
82}
83
84impl<'a, 'w> WindowContext<'a, 'w> {
85 pub(crate) fn mutable(app: &'a mut AppContext, window: &'w mut Window) -> Self {
86 Self {
87 app: Reference::Mutable(app),
88 window: Reference::Mutable(window),
89 }
90 }
91
92 // pub(crate) fn immutable(app: &'a AppContext, window: &'w Window) -> Self {
93 // Self {
94 // app: Reference::Immutable(app),
95 // window: Reference::Immutable(window),
96 // }
97 // }
98
99 pub(crate) fn draw(&mut self) -> Result<()> {
100 let unit_entity = self.unit_entity.clone();
101 self.update_entity(&unit_entity, |_, cx| {
102 let mut root_view = cx.window.root_view.take().unwrap();
103 let (root_layout_id, mut frame_state) = root_view.layout(&mut (), cx)?;
104 let available_space = cx.window.content_size.map(Into::into);
105 cx.window
106 .layout_engine
107 .compute_layout(root_layout_id, available_space)?;
108 let layout = cx.window.layout_engine.layout(root_layout_id)?;
109 root_view.paint(layout, &mut (), &mut frame_state, cx)?;
110 cx.window.root_view = Some(root_view);
111 let scene = cx.window.scene.take();
112 dbg!(&scene);
113 let _ = cx.window.platform_window.read(|platform_window| {
114 platform_window.draw(scene);
115 future::ready(())
116 });
117
118 Ok(())
119 })
120 }
121
122 pub fn request_layout(
123 &mut self,
124 style: Style,
125 children: impl IntoIterator<Item = LayoutId>,
126 ) -> Result<LayoutId> {
127 self.app.layout_id_buffer.clear();
128 self.app.layout_id_buffer.extend(children.into_iter());
129 let rem_size = self.rem_size();
130
131 self.window
132 .layout_engine
133 .request_layout(style, rem_size, &self.app.layout_id_buffer)
134 }
135
136 pub fn request_measured_layout<
137 F: Fn(Size<Option<Pixels>>, Size<AvailableSpace>) -> Size<Pixels> + Send + Sync + 'static,
138 >(
139 &mut self,
140 style: Style,
141 rem_size: Pixels,
142 measure: F,
143 ) -> Result<LayoutId> {
144 self.window
145 .layout_engine
146 .request_measured_layout(style, rem_size, measure)
147 }
148
149 pub fn layout(&mut self, layout_id: LayoutId) -> Result<Layout> {
150 Ok(self
151 .window
152 .layout_engine
153 .layout(layout_id)
154 .map(Into::into)?)
155 }
156
157 pub fn rem_size(&self) -> Pixels {
158 self.window.rem_size
159 }
160
161 pub fn push_text_style(&mut self, text_style: TextStyleRefinement) {
162 self.window.text_style_stack.push(text_style);
163 }
164
165 pub fn pop_text_style(&mut self) {
166 self.window.text_style_stack.pop();
167 }
168
169 pub fn push_cascading_state<T: Send + Sync + 'static>(&mut self, theme: T) {
170 self.window
171 .state_stacks_by_type
172 .entry(TypeId::of::<T>())
173 .or_default()
174 .push(Box::new(theme));
175 }
176
177 pub fn pop_cascading_state<T: Send + Sync + 'static>(&mut self) {
178 self.window
179 .state_stacks_by_type
180 .get_mut(&TypeId::of::<T>())
181 .and_then(|stack| stack.pop())
182 .expect("cascading state not found");
183 }
184
185 pub fn cascading_state<T: Send + Sync + 'static>(&self) -> &T {
186 let type_id = TypeId::of::<T>();
187 self.window
188 .state_stacks_by_type
189 .get(&type_id)
190 .and_then(|stack| stack.last())
191 .expect("no cascading state of the specified type has been pushed")
192 .downcast_ref::<T>()
193 .unwrap()
194 }
195
196 pub fn text_style(&self) -> TextStyle {
197 let mut style = TextStyle::default();
198 for refinement in &self.window.text_style_stack {
199 style.refine(refinement);
200 }
201 style
202 }
203
204 pub fn mouse_position(&self) -> Point<Pixels> {
205 self.window.mouse_position
206 }
207}
208
209impl Context for WindowContext<'_, '_> {
210 type EntityContext<'a, 'w, T: Send + Sync + 'static> = ViewContext<'a, 'w, T>;
211 type Result<T> = T;
212
213 fn entity<T: Send + Sync + 'static>(
214 &mut self,
215 build_entity: impl FnOnce(&mut Self::EntityContext<'_, '_, T>) -> T,
216 ) -> Handle<T> {
217 let id = self.entities.insert(None);
218 let entity = Box::new(build_entity(&mut ViewContext::mutable(
219 &mut *self.app,
220 &mut self.window,
221 id,
222 )));
223 self.entities.get_mut(id).unwrap().replace(entity);
224
225 Handle {
226 id,
227 entity_type: PhantomData,
228 }
229 }
230
231 fn update_entity<T: Send + Sync + 'static, R>(
232 &mut self,
233 handle: &Handle<T>,
234 update: impl FnOnce(&mut T, &mut Self::EntityContext<'_, '_, T>) -> R,
235 ) -> R {
236 let mut entity = self
237 .app
238 .entities
239 .get_mut(handle.id)
240 .unwrap()
241 .take()
242 .unwrap()
243 .downcast::<T>()
244 .unwrap();
245
246 let result = update(
247 &mut *entity,
248 &mut ViewContext::mutable(&mut *self.app, &mut *self.window, handle.id),
249 );
250
251 self.app
252 .entities
253 .get_mut(handle.id)
254 .unwrap()
255 .replace(entity);
256
257 result
258 }
259}
260
261#[derive(Deref, DerefMut)]
262pub struct ViewContext<'a, 'w, T> {
263 #[deref]
264 #[deref_mut]
265 window_cx: WindowContext<'a, 'w>,
266 entity_type: PhantomData<T>,
267 entity_id: EntityId,
268}
269
270impl<'a, 'w, T: Send + Sync + 'static> ViewContext<'a, 'w, T> {
271 fn mutable(app: &'a mut AppContext, window: &'w mut Window, entity_id: EntityId) -> Self {
272 Self {
273 window_cx: WindowContext::mutable(app, window),
274 entity_id,
275 entity_type: PhantomData,
276 }
277 }
278
279 // fn immutable(app: &'a AppContext, window: &'w Window, entity_id: EntityId) -> Self {
280 // Self {
281 // window_cx: WindowContext::immutable(app, window),
282 // entity_id,
283 // entity_type: PhantomData,
284 // }
285 // }
286
287 pub fn erase_state<R>(&mut self, f: impl FnOnce(&mut ViewContext<()>) -> R) -> R {
288 let entity_id = self.unit_entity.id;
289 let mut cx = ViewContext::mutable(
290 &mut *self.window_cx.app,
291 &mut *self.window_cx.window,
292 entity_id,
293 );
294 f(&mut cx)
295 }
296
297 pub fn handle(&self) -> WeakHandle<T> {
298 WeakHandle {
299 id: self.entity_id,
300 entity_type: PhantomData,
301 }
302 }
303
304 pub fn observe<E: Send + Sync + 'static>(
305 &mut self,
306 handle: &Handle<E>,
307 on_notify: impl Fn(&mut T, Handle<E>, &mut ViewContext<'_, '_, T>) + Send + Sync + 'static,
308 ) {
309 let this = self.handle();
310 let handle = handle.downgrade();
311 let window_handle = self.window.handle;
312 self.app
313 .observers
314 .entry(handle.id)
315 .or_default()
316 .push(Arc::new(move |cx| {
317 cx.update_window(window_handle.id, |cx| {
318 if let Some(handle) = handle.upgrade(cx) {
319 this.update(cx, |this, cx| on_notify(this, handle, cx))
320 .is_ok()
321 } else {
322 false
323 }
324 })
325 .unwrap_or(false)
326 }));
327 }
328
329 pub fn notify(&mut self) {
330 let entity_id = self.entity_id;
331 self.app
332 .pending_effects
333 .push_back(Effect::Notify(entity_id));
334 self.window.dirty = true;
335 }
336}
337
338impl<'a, 'w, T: 'static> Context for ViewContext<'a, 'w, T> {
339 type EntityContext<'b, 'c, U: Send + Sync + 'static> = ViewContext<'b, 'c, U>;
340 type Result<U> = U;
341
342 fn entity<T2: Send + Sync + 'static>(
343 &mut self,
344 build_entity: impl FnOnce(&mut Self::EntityContext<'_, '_, T2>) -> T2,
345 ) -> Handle<T2> {
346 self.window_cx.entity(build_entity)
347 }
348
349 fn update_entity<U: Send + Sync + 'static, R>(
350 &mut self,
351 handle: &Handle<U>,
352 update: impl FnOnce(&mut U, &mut Self::EntityContext<'_, '_, U>) -> R,
353 ) -> R {
354 self.window_cx.update_entity(handle, update)
355 }
356}
357
358// #[derive(Clone, Copy, Eq, PartialEq, Hash)]
359slotmap::new_key_type! { pub struct WindowId; }
360
361#[derive(PartialEq, Eq)]
362pub struct WindowHandle<S> {
363 id: WindowId,
364 state_type: PhantomData<S>,
365}
366
367impl<S> Copy for WindowHandle<S> {}
368
369impl<S> Clone for WindowHandle<S> {
370 fn clone(&self) -> Self {
371 WindowHandle {
372 id: self.id,
373 state_type: PhantomData,
374 }
375 }
376}
377
378impl<S> WindowHandle<S> {
379 pub fn new(id: WindowId) -> Self {
380 WindowHandle {
381 id,
382 state_type: PhantomData,
383 }
384 }
385}
386
387impl<S: 'static> Into<AnyWindowHandle> for WindowHandle<S> {
388 fn into(self) -> AnyWindowHandle {
389 AnyWindowHandle {
390 id: self.id,
391 state_type: TypeId::of::<S>(),
392 }
393 }
394}
395
396#[derive(Copy, Clone, PartialEq, Eq)]
397pub struct AnyWindowHandle {
398 pub(crate) id: WindowId,
399 state_type: TypeId,
400}
401
402#[derive(Clone)]
403pub struct Layout {
404 pub order: u32,
405 pub bounds: Bounds<Pixels>,
406}