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, 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> ReadModel for LayoutContext<'a> {
268 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
269 self.app.read_model(handle)
270 }
271}
272
273pub struct PaintContext<'a> {
274 rendered_views: &'a mut HashMap<usize, ElementBox>,
275 pub scene: &'a mut Scene,
276 pub font_cache: &'a FontCache,
277 pub text_layout_cache: &'a TextLayoutCache,
278 pub app: &'a AppContext,
279}
280
281impl<'a> PaintContext<'a> {
282 fn paint(&mut self, view_id: usize, origin: Vector2F, visible_bounds: RectF) {
283 if let Some(mut tree) = self.rendered_views.remove(&view_id) {
284 tree.paint(origin, visible_bounds, self);
285 self.rendered_views.insert(view_id, tree);
286 }
287 }
288}
289
290impl<'a> Deref for PaintContext<'a> {
291 type Target = AppContext;
292
293 fn deref(&self) -> &Self::Target {
294 self.app
295 }
296}
297
298pub struct EventContext<'a> {
299 rendered_views: &'a mut HashMap<usize, ElementBox>,
300 dispatched_actions: Vec<DispatchDirective>,
301 pub font_cache: &'a FontCache,
302 pub text_layout_cache: &'a TextLayoutCache,
303 pub app: &'a mut MutableAppContext,
304 pub notify_count: usize,
305 view_stack: Vec<usize>,
306 invalidated_views: HashSet<usize>,
307}
308
309impl<'a> EventContext<'a> {
310 fn dispatch_event(&mut self, view_id: usize, event: &Event) -> bool {
311 if let Some(mut element) = self.rendered_views.remove(&view_id) {
312 self.view_stack.push(view_id);
313 let result = element.dispatch_event(event, self);
314 self.view_stack.pop();
315 self.rendered_views.insert(view_id, element);
316 result
317 } else {
318 false
319 }
320 }
321
322 pub fn dispatch_action<A: Action>(&mut self, action: A) {
323 self.dispatched_actions.push(DispatchDirective {
324 path: self.view_stack.clone(),
325 action: Box::new(action),
326 });
327 }
328
329 pub fn notify(&mut self) {
330 self.notify_count += 1;
331 if let Some(view_id) = self.view_stack.last() {
332 self.invalidated_views.insert(*view_id);
333 }
334 }
335
336 pub fn notify_count(&self) -> usize {
337 self.notify_count
338 }
339}
340
341impl<'a> Deref for EventContext<'a> {
342 type Target = MutableAppContext;
343
344 fn deref(&self) -> &Self::Target {
345 self.app
346 }
347}
348
349impl<'a> DerefMut for EventContext<'a> {
350 fn deref_mut(&mut self) -> &mut Self::Target {
351 self.app
352 }
353}
354
355pub struct DebugContext<'a> {
356 rendered_views: &'a HashMap<usize, ElementBox>,
357 pub font_cache: &'a FontCache,
358 pub app: &'a AppContext,
359}
360
361#[derive(Clone, Copy, Debug, Eq, PartialEq)]
362pub enum Axis {
363 Horizontal,
364 Vertical,
365}
366
367impl Axis {
368 pub fn invert(self) -> Self {
369 match self {
370 Self::Horizontal => Self::Vertical,
371 Self::Vertical => Self::Horizontal,
372 }
373 }
374}
375
376impl ToJson for Axis {
377 fn to_json(&self) -> serde_json::Value {
378 match self {
379 Axis::Horizontal => json!("horizontal"),
380 Axis::Vertical => json!("vertical"),
381 }
382 }
383}
384
385pub trait Vector2FExt {
386 fn along(self, axis: Axis) -> f32;
387}
388
389impl Vector2FExt for Vector2F {
390 fn along(self, axis: Axis) -> f32 {
391 match axis {
392 Axis::Horizontal => self.x(),
393 Axis::Vertical => self.y(),
394 }
395 }
396}
397
398#[derive(Copy, Clone, Debug)]
399pub struct SizeConstraint {
400 pub min: Vector2F,
401 pub max: Vector2F,
402}
403
404impl SizeConstraint {
405 pub fn new(min: Vector2F, max: Vector2F) -> Self {
406 Self { min, max }
407 }
408
409 pub fn strict(size: Vector2F) -> Self {
410 Self {
411 min: size,
412 max: size,
413 }
414 }
415
416 pub fn strict_along(axis: Axis, max: f32) -> Self {
417 match axis {
418 Axis::Horizontal => Self {
419 min: vec2f(max, 0.0),
420 max: vec2f(max, f32::INFINITY),
421 },
422 Axis::Vertical => Self {
423 min: vec2f(0.0, max),
424 max: vec2f(f32::INFINITY, max),
425 },
426 }
427 }
428
429 pub fn max_along(&self, axis: Axis) -> f32 {
430 match axis {
431 Axis::Horizontal => self.max.x(),
432 Axis::Vertical => self.max.y(),
433 }
434 }
435
436 pub fn min_along(&self, axis: Axis) -> f32 {
437 match axis {
438 Axis::Horizontal => self.min.x(),
439 Axis::Vertical => self.min.y(),
440 }
441 }
442
443 pub fn constrain(&self, size: Vector2F) -> Vector2F {
444 vec2f(
445 size.x().min(self.max.x()).max(self.min.x()),
446 size.y().min(self.max.y()).max(self.min.y()),
447 )
448 }
449}
450
451impl ToJson for SizeConstraint {
452 fn to_json(&self) -> serde_json::Value {
453 json!({
454 "min": self.min.to_json(),
455 "max": self.max.to_json(),
456 })
457 }
458}
459
460pub struct ChildView {
461 view_id: usize,
462}
463
464impl ChildView {
465 pub fn new(view_id: usize) -> Self {
466 Self { view_id }
467 }
468}
469
470impl Element for ChildView {
471 type LayoutState = ();
472 type PaintState = ();
473
474 fn layout(
475 &mut self,
476 constraint: SizeConstraint,
477 cx: &mut LayoutContext,
478 ) -> (Vector2F, Self::LayoutState) {
479 let size = cx.layout(self.view_id, constraint);
480 (size, ())
481 }
482
483 fn paint(
484 &mut self,
485 bounds: RectF,
486 visible_bounds: RectF,
487 _: &mut Self::LayoutState,
488 cx: &mut PaintContext,
489 ) -> Self::PaintState {
490 cx.paint(self.view_id, bounds.origin(), visible_bounds);
491 }
492
493 fn dispatch_event(
494 &mut self,
495 event: &Event,
496 _: RectF,
497 _: &mut Self::LayoutState,
498 _: &mut Self::PaintState,
499 cx: &mut EventContext,
500 ) -> bool {
501 cx.dispatch_event(self.view_id, event)
502 }
503
504 fn debug(
505 &self,
506 bounds: RectF,
507 _: &Self::LayoutState,
508 _: &Self::PaintState,
509 cx: &DebugContext,
510 ) -> serde_json::Value {
511 json!({
512 "type": "ChildView",
513 "view_id": self.view_id,
514 "bounds": bounds.to_json(),
515 "child": if let Some(view) = cx.rendered_views.get(&self.view_id) {
516 view.debug(cx)
517 } else {
518 json!(null)
519 }
520 })
521 }
522}
523
524#[cfg(test)]
525mod tests {
526 // #[test]
527 // fn test_responder_chain() {
528 // let settings = settings_rx(None);
529 // let mut app = App::new().unwrap();
530 // let workspace = app.add_model(|cx| Workspace::new(Vec::new(), cx));
531 // let (window_id, workspace_view) =
532 // app.add_window(|cx| WorkspaceView::new(workspace.clone(), settings, cx));
533
534 // let invalidations = Rc::new(RefCell::new(Vec::new()));
535 // let invalidations_ = invalidations.clone();
536 // app.on_window_invalidated(window_id, move |invalidation, _| {
537 // invalidations_.borrow_mut().push(invalidation)
538 // });
539
540 // let active_pane_id = workspace_view.update(&mut app, |view, cx| {
541 // cx.focus(view.active_pane());
542 // view.active_pane().id()
543 // });
544
545 // app.update(|app| {
546 // let mut presenter = Presenter::new(
547 // window_id,
548 // Rc::new(FontCache::new()),
549 // Rc::new(AssetCache::new()),
550 // app,
551 // );
552 // for invalidation in invalidations.borrow().iter().cloned() {
553 // presenter.update(vec2f(1024.0, 768.0), 2.0, Some(invalidation), app);
554 // }
555
556 // assert_eq!(
557 // presenter.responder_chain(app.cx()).unwrap(),
558 // vec![workspace_view.id(), active_pane_id]
559 // );
560 // });
561 // }
562}