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