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