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