1use crate::{
2 app::{AppContext, MutableAppContext, WindowInvalidation},
3 elements::Element,
4 font_cache::FontCache,
5 geometry::rect::RectF,
6 json::{self, ToJson},
7 platform::Event,
8 text_layout::TextLayoutCache,
9 Action, AnyAction, AnyModelHandle, AnyViewHandle, AnyWeakModelHandle, AssetCache, ElementBox,
10 ElementStateContext, Entity, FontSystem, ModelHandle, ReadModel, ReadView, Scene,
11 UpgradeModelHandle, UpgradeViewHandle, View, ViewHandle, WeakModelHandle, WeakViewHandle,
12};
13use pathfinder_geometry::vector::{vec2f, Vector2F};
14use serde_json::json;
15use std::{
16 collections::{HashMap, HashSet},
17 ops::{Deref, DerefMut},
18 sync::Arc,
19};
20
21pub struct Presenter {
22 window_id: usize,
23 rendered_views: HashMap<usize, ElementBox>,
24 parents: HashMap<usize, usize>,
25 font_cache: Arc<FontCache>,
26 text_layout_cache: TextLayoutCache,
27 asset_cache: Arc<AssetCache>,
28 last_mouse_moved_event: Option<Event>,
29 titlebar_height: f32,
30}
31
32impl Presenter {
33 pub fn new(
34 window_id: usize,
35 titlebar_height: f32,
36 font_cache: Arc<FontCache>,
37 text_layout_cache: TextLayoutCache,
38 asset_cache: Arc<AssetCache>,
39 cx: &mut MutableAppContext,
40 ) -> Self {
41 Self {
42 window_id,
43 rendered_views: cx.render_views(window_id, titlebar_height),
44 parents: HashMap::new(),
45 font_cache,
46 text_layout_cache,
47 asset_cache,
48 last_mouse_moved_event: None,
49 titlebar_height,
50 }
51 }
52
53 pub fn dispatch_path(&self, app: &AppContext) -> Vec<usize> {
54 let mut view_id = app.focused_view_id(self.window_id).unwrap();
55 let mut path = vec![view_id];
56 while let Some(parent_id) = self.parents.get(&view_id).copied() {
57 path.push(parent_id);
58 view_id = parent_id;
59 }
60 path.reverse();
61 path
62 }
63
64 pub fn invalidate(&mut self, mut invalidation: WindowInvalidation, cx: &mut MutableAppContext) {
65 cx.start_frame();
66 for view_id in invalidation.removed {
67 invalidation.updated.remove(&view_id);
68 self.rendered_views.remove(&view_id);
69 self.parents.remove(&view_id);
70 }
71 for view_id in invalidation.updated {
72 self.rendered_views.insert(
73 view_id,
74 cx.render_view(self.window_id, view_id, self.titlebar_height, false)
75 .unwrap(),
76 );
77 }
78 }
79
80 pub fn refresh(
81 &mut self,
82 invalidation: Option<WindowInvalidation>,
83 cx: &mut MutableAppContext,
84 ) {
85 cx.start_frame();
86 if let Some(invalidation) = invalidation {
87 for view_id in invalidation.removed {
88 self.rendered_views.remove(&view_id);
89 self.parents.remove(&view_id);
90 }
91 }
92
93 for (view_id, view) in &mut self.rendered_views {
94 *view = cx
95 .render_view(self.window_id, *view_id, self.titlebar_height, true)
96 .unwrap();
97 }
98 }
99
100 pub fn build_scene(
101 &mut self,
102 window_size: Vector2F,
103 scale_factor: f32,
104 refreshing: bool,
105 cx: &mut MutableAppContext,
106 ) -> Scene {
107 let mut scene = Scene::new(scale_factor);
108
109 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
110 self.layout(window_size, refreshing, cx);
111 let mut paint_cx = PaintContext {
112 scene: &mut scene,
113 font_cache: &self.font_cache,
114 text_layout_cache: &self.text_layout_cache,
115 rendered_views: &mut self.rendered_views,
116 app: cx.as_ref(),
117 };
118 paint_cx.paint(
119 root_view_id,
120 Vector2F::zero(),
121 RectF::new(Vector2F::zero(), window_size),
122 );
123 self.text_layout_cache.finish_frame();
124
125 if let Some(event) = self.last_mouse_moved_event.clone() {
126 self.dispatch_event(event, cx)
127 }
128 } else {
129 log::error!("could not find root_view_id for window {}", self.window_id);
130 }
131
132 scene
133 }
134
135 fn layout(&mut self, size: Vector2F, refreshing: bool, cx: &mut MutableAppContext) {
136 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
137 self.build_layout_context(refreshing, cx)
138 .layout(root_view_id, SizeConstraint::strict(size));
139 }
140 }
141
142 pub fn build_layout_context<'a>(
143 &'a mut self,
144 refreshing: bool,
145 cx: &'a mut MutableAppContext,
146 ) -> LayoutContext<'a> {
147 LayoutContext {
148 rendered_views: &mut self.rendered_views,
149 parents: &mut self.parents,
150 refreshing,
151 font_cache: &self.font_cache,
152 font_system: cx.platform().fonts(),
153 text_layout_cache: &self.text_layout_cache,
154 asset_cache: &self.asset_cache,
155 view_stack: Vec::new(),
156 app: cx,
157 }
158 }
159
160 pub fn dispatch_event(&mut self, event: Event, cx: &mut MutableAppContext) {
161 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
162 match event {
163 Event::MouseMoved { .. } => {
164 self.last_mouse_moved_event = Some(event.clone());
165 }
166 Event::LeftMouseDragged { position } => {
167 self.last_mouse_moved_event = Some(Event::MouseMoved {
168 position,
169 left_mouse_down: true,
170 });
171 }
172 _ => {}
173 }
174
175 let mut event_cx = self.build_event_context(cx);
176 event_cx.dispatch_event(root_view_id, &event);
177
178 let invalidated_views = event_cx.invalidated_views;
179 let dispatch_directives = event_cx.dispatched_actions;
180
181 for view_id in invalidated_views {
182 cx.notify_view(self.window_id, view_id);
183 }
184 for directive in dispatch_directives {
185 cx.dispatch_action_any(self.window_id, &directive.path, directive.action.as_ref());
186 }
187 }
188 }
189
190 pub fn build_event_context<'a>(
191 &'a mut self,
192 cx: &'a mut MutableAppContext,
193 ) -> EventContext<'a> {
194 EventContext {
195 rendered_views: &mut self.rendered_views,
196 dispatched_actions: Default::default(),
197 font_cache: &self.font_cache,
198 text_layout_cache: &self.text_layout_cache,
199 view_stack: Default::default(),
200 invalidated_views: Default::default(),
201 notify_count: 0,
202 app: cx,
203 }
204 }
205
206 pub fn debug_elements(&self, cx: &AppContext) -> Option<json::Value> {
207 cx.root_view_id(self.window_id)
208 .and_then(|root_view_id| self.rendered_views.get(&root_view_id))
209 .map(|root_element| {
210 root_element.debug(&DebugContext {
211 rendered_views: &self.rendered_views,
212 font_cache: &self.font_cache,
213 app: cx,
214 })
215 })
216 }
217}
218
219pub struct DispatchDirective {
220 pub path: Vec<usize>,
221 pub action: Box<dyn AnyAction>,
222}
223
224pub struct LayoutContext<'a> {
225 rendered_views: &'a mut HashMap<usize, ElementBox>,
226 parents: &'a mut HashMap<usize, usize>,
227 view_stack: Vec<usize>,
228 pub refreshing: bool,
229 pub font_cache: &'a Arc<FontCache>,
230 pub font_system: Arc<dyn FontSystem>,
231 pub text_layout_cache: &'a TextLayoutCache,
232 pub asset_cache: &'a AssetCache,
233 pub app: &'a mut MutableAppContext,
234}
235
236impl<'a> LayoutContext<'a> {
237 fn layout(&mut self, view_id: usize, constraint: SizeConstraint) -> Vector2F {
238 if let Some(parent_id) = self.view_stack.last() {
239 self.parents.insert(view_id, *parent_id);
240 }
241 self.view_stack.push(view_id);
242 let mut rendered_view = self.rendered_views.remove(&view_id).unwrap();
243 let size = rendered_view.layout(constraint, self);
244 self.rendered_views.insert(view_id, rendered_view);
245 self.view_stack.pop();
246 size
247 }
248}
249
250impl<'a> Deref for LayoutContext<'a> {
251 type Target = MutableAppContext;
252
253 fn deref(&self) -> &Self::Target {
254 self.app
255 }
256}
257
258impl<'a> DerefMut for LayoutContext<'a> {
259 fn deref_mut(&mut self) -> &mut Self::Target {
260 self.app
261 }
262}
263
264impl<'a> ReadView for LayoutContext<'a> {
265 fn read_view<T: View>(&self, handle: &ViewHandle<T>) -> &T {
266 self.app.read_view(handle)
267 }
268}
269
270impl<'a> ReadModel for LayoutContext<'a> {
271 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
272 self.app.read_model(handle)
273 }
274}
275
276impl<'a> UpgradeModelHandle for LayoutContext<'a> {
277 fn upgrade_model_handle<T: Entity>(
278 &self,
279 handle: &WeakModelHandle<T>,
280 ) -> Option<ModelHandle<T>> {
281 self.app.upgrade_model_handle(handle)
282 }
283
284 fn model_handle_is_upgradable<T: Entity>(&self, handle: &WeakModelHandle<T>) -> bool {
285 self.app.model_handle_is_upgradable(handle)
286 }
287
288 fn upgrade_any_model_handle(&self, handle: &AnyWeakModelHandle) -> Option<AnyModelHandle> {
289 self.app.upgrade_any_model_handle(handle)
290 }
291}
292
293impl<'a> UpgradeViewHandle for LayoutContext<'a> {
294 fn upgrade_view_handle<T: View>(&self, handle: &WeakViewHandle<T>) -> Option<ViewHandle<T>> {
295 self.app.upgrade_view_handle(handle)
296 }
297}
298
299impl<'a> ElementStateContext for LayoutContext<'a> {
300 fn current_view_id(&self) -> usize {
301 *self.view_stack.last().unwrap()
302 }
303}
304
305pub struct PaintContext<'a> {
306 rendered_views: &'a mut HashMap<usize, ElementBox>,
307 pub scene: &'a mut Scene,
308 pub font_cache: &'a FontCache,
309 pub text_layout_cache: &'a TextLayoutCache,
310 pub app: &'a AppContext,
311}
312
313impl<'a> PaintContext<'a> {
314 fn paint(&mut self, view_id: usize, origin: Vector2F, visible_bounds: RectF) {
315 if let Some(mut tree) = self.rendered_views.remove(&view_id) {
316 tree.paint(origin, visible_bounds, self);
317 self.rendered_views.insert(view_id, tree);
318 }
319 }
320}
321
322impl<'a> Deref for PaintContext<'a> {
323 type Target = AppContext;
324
325 fn deref(&self) -> &Self::Target {
326 self.app
327 }
328}
329
330pub struct EventContext<'a> {
331 rendered_views: &'a mut HashMap<usize, ElementBox>,
332 dispatched_actions: Vec<DispatchDirective>,
333 pub font_cache: &'a FontCache,
334 pub text_layout_cache: &'a TextLayoutCache,
335 pub app: &'a mut MutableAppContext,
336 pub notify_count: usize,
337 view_stack: Vec<usize>,
338 invalidated_views: HashSet<usize>,
339}
340
341impl<'a> EventContext<'a> {
342 fn dispatch_event(&mut self, view_id: usize, event: &Event) -> bool {
343 if let Some(mut element) = self.rendered_views.remove(&view_id) {
344 self.view_stack.push(view_id);
345 let result = element.dispatch_event(event, self);
346 self.view_stack.pop();
347 self.rendered_views.insert(view_id, element);
348 result
349 } else {
350 false
351 }
352 }
353
354 pub fn dispatch_action<A: Action>(&mut self, action: A) {
355 self.dispatched_actions.push(DispatchDirective {
356 path: self.view_stack.clone(),
357 action: Box::new(action),
358 });
359 }
360
361 pub fn notify(&mut self) {
362 self.notify_count += 1;
363 if let Some(view_id) = self.view_stack.last() {
364 self.invalidated_views.insert(*view_id);
365 }
366 }
367
368 pub fn notify_count(&self) -> usize {
369 self.notify_count
370 }
371}
372
373impl<'a> Deref for EventContext<'a> {
374 type Target = MutableAppContext;
375
376 fn deref(&self) -> &Self::Target {
377 self.app
378 }
379}
380
381impl<'a> DerefMut for EventContext<'a> {
382 fn deref_mut(&mut self) -> &mut Self::Target {
383 self.app
384 }
385}
386
387pub struct DebugContext<'a> {
388 rendered_views: &'a HashMap<usize, ElementBox>,
389 pub font_cache: &'a FontCache,
390 pub app: &'a AppContext,
391}
392
393#[derive(Clone, Copy, Debug, Eq, PartialEq)]
394pub enum Axis {
395 Horizontal,
396 Vertical,
397}
398
399impl Axis {
400 pub fn invert(self) -> Self {
401 match self {
402 Self::Horizontal => Self::Vertical,
403 Self::Vertical => Self::Horizontal,
404 }
405 }
406}
407
408impl ToJson for Axis {
409 fn to_json(&self) -> serde_json::Value {
410 match self {
411 Axis::Horizontal => json!("horizontal"),
412 Axis::Vertical => json!("vertical"),
413 }
414 }
415}
416
417pub trait Vector2FExt {
418 fn along(self, axis: Axis) -> f32;
419}
420
421impl Vector2FExt for Vector2F {
422 fn along(self, axis: Axis) -> f32 {
423 match axis {
424 Axis::Horizontal => self.x(),
425 Axis::Vertical => self.y(),
426 }
427 }
428}
429
430#[derive(Copy, Clone, Debug)]
431pub struct SizeConstraint {
432 pub min: Vector2F,
433 pub max: Vector2F,
434}
435
436impl SizeConstraint {
437 pub fn new(min: Vector2F, max: Vector2F) -> Self {
438 Self { min, max }
439 }
440
441 pub fn strict(size: Vector2F) -> Self {
442 Self {
443 min: size,
444 max: size,
445 }
446 }
447
448 pub fn strict_along(axis: Axis, max: f32) -> Self {
449 match axis {
450 Axis::Horizontal => Self {
451 min: vec2f(max, 0.0),
452 max: vec2f(max, f32::INFINITY),
453 },
454 Axis::Vertical => Self {
455 min: vec2f(0.0, max),
456 max: vec2f(f32::INFINITY, max),
457 },
458 }
459 }
460
461 pub fn max_along(&self, axis: Axis) -> f32 {
462 match axis {
463 Axis::Horizontal => self.max.x(),
464 Axis::Vertical => self.max.y(),
465 }
466 }
467
468 pub fn min_along(&self, axis: Axis) -> f32 {
469 match axis {
470 Axis::Horizontal => self.min.x(),
471 Axis::Vertical => self.min.y(),
472 }
473 }
474
475 pub fn constrain(&self, size: Vector2F) -> Vector2F {
476 vec2f(
477 size.x().min(self.max.x()).max(self.min.x()),
478 size.y().min(self.max.y()).max(self.min.y()),
479 )
480 }
481}
482
483impl ToJson for SizeConstraint {
484 fn to_json(&self) -> serde_json::Value {
485 json!({
486 "min": self.min.to_json(),
487 "max": self.max.to_json(),
488 })
489 }
490}
491
492pub struct ChildView {
493 view_id: usize,
494}
495
496impl ChildView {
497 pub fn new(view: impl Into<AnyViewHandle>) -> Self {
498 Self {
499 view_id: view.into().id(),
500 }
501 }
502}
503
504impl Element for ChildView {
505 type LayoutState = ();
506 type PaintState = ();
507
508 fn layout(
509 &mut self,
510 constraint: SizeConstraint,
511 cx: &mut LayoutContext,
512 ) -> (Vector2F, Self::LayoutState) {
513 let size = cx.layout(self.view_id, constraint);
514 (size, ())
515 }
516
517 fn paint(
518 &mut self,
519 bounds: RectF,
520 visible_bounds: RectF,
521 _: &mut Self::LayoutState,
522 cx: &mut PaintContext,
523 ) -> Self::PaintState {
524 cx.paint(self.view_id, bounds.origin(), visible_bounds);
525 }
526
527 fn dispatch_event(
528 &mut self,
529 event: &Event,
530 _: RectF,
531 _: &mut Self::LayoutState,
532 _: &mut Self::PaintState,
533 cx: &mut EventContext,
534 ) -> bool {
535 cx.dispatch_event(self.view_id, event)
536 }
537
538 fn debug(
539 &self,
540 bounds: RectF,
541 _: &Self::LayoutState,
542 _: &Self::PaintState,
543 cx: &DebugContext,
544 ) -> serde_json::Value {
545 json!({
546 "type": "ChildView",
547 "view_id": self.view_id,
548 "bounds": bounds.to_json(),
549 "child": if let Some(view) = cx.rendered_views.get(&self.view_id) {
550 view.debug(cx)
551 } else {
552 json!(null)
553 }
554 })
555 }
556}
557
558#[cfg(test)]
559mod tests {
560 // #[test]
561 // fn test_responder_chain() {
562 // let settings = settings_rx(None);
563 // let mut app = App::new().unwrap();
564 // let workspace = app.add_model(|cx| Workspace::new(Vec::new(), cx));
565 // let (window_id, workspace_view) =
566 // app.add_window(|cx| WorkspaceView::new(workspace.clone(), settings, cx));
567
568 // let invalidations = Rc::new(RefCell::new(Vec::new()));
569 // let invalidations_ = invalidations.clone();
570 // app.on_window_invalidated(window_id, move |invalidation, _| {
571 // invalidations_.borrow_mut().push(invalidation)
572 // });
573
574 // let active_pane_id = workspace_view.update(&mut app, |view, cx| {
575 // cx.focus(view.active_pane());
576 // view.active_pane().id()
577 // });
578
579 // app.update(|app| {
580 // let mut presenter = Presenter::new(
581 // window_id,
582 // Rc::new(FontCache::new()),
583 // Rc::new(AssetCache::new()),
584 // app,
585 // );
586 // for invalidation in invalidations.borrow().iter().cloned() {
587 // presenter.update(vec2f(1024.0, 768.0), 2.0, Some(invalidation), app);
588 // }
589
590 // assert_eq!(
591 // presenter.responder_chain(app.cx()).unwrap(),
592 // vec![workspace_view.id(), active_pane_id]
593 // );
594 // });
595 // }
596}