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