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