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