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