1use crate::{
2 app::{AppContext, MutableAppContext, WindowInvalidation},
3 elements::Element,
4 fonts::FontCache,
5 platform::Event,
6 text_layout::TextLayoutCache,
7 AssetCache, Scene,
8};
9use pathfinder_geometry::vector::{vec2f, Vector2F};
10use std::{any::Any, collections::HashMap, sync::Arc};
11
12pub struct Presenter {
13 window_id: usize,
14 rendered_views: HashMap<usize, Box<dyn Element>>,
15 parents: HashMap<usize, usize>,
16 font_cache: Arc<FontCache>,
17 text_layout_cache: TextLayoutCache,
18 asset_cache: Arc<AssetCache>,
19}
20
21impl Presenter {
22 pub fn new(
23 window_id: usize,
24 font_cache: Arc<FontCache>,
25 asset_cache: Arc<AssetCache>,
26 app: &MutableAppContext,
27 ) -> Self {
28 Self {
29 window_id,
30 rendered_views: app.render_views(window_id).unwrap(),
31 parents: HashMap::new(),
32 font_cache,
33 text_layout_cache: TextLayoutCache::new(),
34 asset_cache,
35 }
36 }
37
38 pub fn invalidate(&mut self, invalidation: WindowInvalidation, app: &AppContext) {
39 for view_id in invalidation.updated {
40 self.rendered_views
41 .insert(view_id, app.render_view(self.window_id, view_id).unwrap());
42 }
43 for view_id in invalidation.removed {
44 self.rendered_views.remove(&view_id);
45 self.parents.remove(&view_id);
46 }
47 }
48
49 pub fn build_scene(
50 &mut self,
51 window_size: Vector2F,
52 scale_factor: f32,
53 app: &mut MutableAppContext,
54 ) -> Scene {
55 let mut scene = Scene::new(scale_factor);
56
57 if let Some(root_view_id) = app.root_view_id(self.window_id) {
58 self.layout(window_size, app.downgrade());
59 self.after_layout(app);
60 let mut paint_ctx = PaintContext {
61 scene: &mut scene,
62 font_cache: &self.font_cache,
63 text_layout_cache: &self.text_layout_cache,
64 rendered_views: &mut self.rendered_views,
65 };
66 paint_ctx.paint(root_view_id, Vector2F::zero(), app.downgrade());
67 self.text_layout_cache.finish_frame();
68 } else {
69 log::error!("could not find root_view_id for window {}", self.window_id);
70 }
71
72 scene
73 }
74
75 fn layout(&mut self, size: Vector2F, app: &AppContext) {
76 if let Some(root_view_id) = app.root_view_id(self.window_id) {
77 let mut layout_ctx = LayoutContext {
78 rendered_views: &mut self.rendered_views,
79 parents: &mut self.parents,
80 font_cache: &self.font_cache,
81 text_layout_cache: &self.text_layout_cache,
82 asset_cache: &self.asset_cache,
83 view_stack: Vec::new(),
84 };
85 layout_ctx.layout(root_view_id, SizeConstraint::strict(size), app);
86 }
87 }
88
89 fn after_layout(&mut self, app: &mut MutableAppContext) {
90 if let Some(root_view_id) = app.root_view_id(self.window_id) {
91 let mut ctx = AfterLayoutContext {
92 rendered_views: &mut self.rendered_views,
93 font_cache: &self.font_cache,
94 text_layout_cache: &self.text_layout_cache,
95 };
96 ctx.after_layout(root_view_id, app);
97 }
98 }
99
100 pub fn responder_chain(&self, app: &AppContext) -> Option<Vec<usize>> {
101 app.focused_view_id(self.window_id).map(|mut view_id| {
102 let mut chain = vec![view_id];
103 while let Some(parent_id) = self.parents.get(&view_id) {
104 view_id = *parent_id;
105 chain.push(view_id);
106 }
107 chain.reverse();
108 chain
109 })
110 }
111
112 pub fn dispatch_event(&self, event: Event, app: &AppContext) -> Vec<ActionToDispatch> {
113 let mut event_ctx = EventContext {
114 rendered_views: &self.rendered_views,
115 actions: Vec::new(),
116 font_cache: &self.font_cache,
117 text_layout_cache: &self.text_layout_cache,
118 view_stack: Vec::new(),
119 };
120 if let Some(root_view_id) = app.root_view_id(self.window_id) {
121 event_ctx.dispatch_event_on_view(root_view_id, &event, app);
122 }
123 event_ctx.actions
124 }
125}
126
127pub struct ActionToDispatch {
128 pub path: Vec<usize>,
129 pub name: &'static str,
130 pub arg: Box<dyn Any>,
131}
132
133pub struct LayoutContext<'a> {
134 rendered_views: &'a mut HashMap<usize, Box<dyn Element>>,
135 parents: &'a mut HashMap<usize, usize>,
136 pub font_cache: &'a FontCache,
137 pub text_layout_cache: &'a TextLayoutCache,
138 pub asset_cache: &'a AssetCache,
139 view_stack: Vec<usize>,
140}
141
142impl<'a> LayoutContext<'a> {
143 fn layout(&mut self, view_id: usize, constraint: SizeConstraint, app: &AppContext) -> Vector2F {
144 if let Some(parent_id) = self.view_stack.last() {
145 self.parents.insert(view_id, *parent_id);
146 }
147 self.view_stack.push(view_id);
148 let mut rendered_view = self.rendered_views.remove(&view_id).unwrap();
149 let size = rendered_view.layout(constraint, self, app);
150 self.rendered_views.insert(view_id, rendered_view);
151 self.view_stack.pop();
152 size
153 }
154}
155
156pub struct AfterLayoutContext<'a> {
157 rendered_views: &'a mut HashMap<usize, Box<dyn Element>>,
158 pub font_cache: &'a FontCache,
159 pub text_layout_cache: &'a TextLayoutCache,
160}
161
162impl<'a> AfterLayoutContext<'a> {
163 fn after_layout(&mut self, view_id: usize, app: &mut MutableAppContext) {
164 if let Some(mut view) = self.rendered_views.remove(&view_id) {
165 view.after_layout(self, app);
166 self.rendered_views.insert(view_id, view);
167 }
168 }
169}
170
171pub struct PaintContext<'a> {
172 rendered_views: &'a mut HashMap<usize, Box<dyn Element>>,
173 pub scene: &'a mut Scene,
174 pub font_cache: &'a FontCache,
175 pub text_layout_cache: &'a TextLayoutCache,
176}
177
178impl<'a> PaintContext<'a> {
179 fn paint(&mut self, view_id: usize, origin: Vector2F, app: &AppContext) {
180 if let Some(mut tree) = self.rendered_views.remove(&view_id) {
181 tree.paint(origin, self, app);
182 self.rendered_views.insert(view_id, tree);
183 }
184 }
185}
186
187pub struct EventContext<'a> {
188 rendered_views: &'a HashMap<usize, Box<dyn Element>>,
189 actions: Vec<ActionToDispatch>,
190 pub font_cache: &'a FontCache,
191 pub text_layout_cache: &'a TextLayoutCache,
192 view_stack: Vec<usize>,
193}
194
195impl<'a> EventContext<'a> {
196 pub fn dispatch_event_on_view(
197 &mut self,
198 view_id: usize,
199 event: &Event,
200 app: &AppContext,
201 ) -> bool {
202 if let Some(element) = self.rendered_views.get(&view_id) {
203 self.view_stack.push(view_id);
204 let result = element.dispatch_event(event, self, app);
205 self.view_stack.pop();
206 result
207 } else {
208 false
209 }
210 }
211
212 pub fn dispatch_action<A: 'static + Any>(&mut self, name: &'static str, arg: A) {
213 self.actions.push(ActionToDispatch {
214 path: self.view_stack.clone(),
215 name,
216 arg: Box::new(arg),
217 });
218 }
219}
220
221#[derive(Clone, Copy, Debug, Eq, PartialEq)]
222pub enum Axis {
223 Horizontal,
224 Vertical,
225}
226
227impl Axis {
228 pub fn invert(self) -> Self {
229 match self {
230 Self::Horizontal => Self::Vertical,
231 Self::Vertical => Self::Horizontal,
232 }
233 }
234}
235
236pub trait Vector2FExt {
237 fn along(self, axis: Axis) -> f32;
238}
239
240impl Vector2FExt for Vector2F {
241 fn along(self, axis: Axis) -> f32 {
242 match axis {
243 Axis::Horizontal => self.x(),
244 Axis::Vertical => self.y(),
245 }
246 }
247}
248
249#[derive(Copy, Clone, Debug)]
250pub struct SizeConstraint {
251 pub min: Vector2F,
252 pub max: Vector2F,
253}
254
255impl SizeConstraint {
256 pub fn new(min: Vector2F, max: Vector2F) -> Self {
257 Self { min, max }
258 }
259
260 pub fn strict(size: Vector2F) -> Self {
261 Self {
262 min: size,
263 max: size,
264 }
265 }
266
267 pub fn strict_along(axis: Axis, max: f32) -> Self {
268 match axis {
269 Axis::Horizontal => Self {
270 min: vec2f(max, 0.0),
271 max: vec2f(max, f32::INFINITY),
272 },
273 Axis::Vertical => Self {
274 min: vec2f(0.0, max),
275 max: vec2f(f32::INFINITY, max),
276 },
277 }
278 }
279
280 pub fn max_along(&self, axis: Axis) -> f32 {
281 match axis {
282 Axis::Horizontal => self.max.x(),
283 Axis::Vertical => self.max.y(),
284 }
285 }
286}
287
288pub struct ChildView {
289 view_id: usize,
290 size: Option<Vector2F>,
291 origin: Option<Vector2F>,
292}
293
294impl ChildView {
295 pub fn new(view_id: usize) -> Self {
296 Self {
297 view_id,
298 size: None,
299 origin: None,
300 }
301 }
302}
303
304impl Element for ChildView {
305 fn layout(
306 &mut self,
307 constraint: SizeConstraint,
308 ctx: &mut LayoutContext,
309 app: &AppContext,
310 ) -> Vector2F {
311 let size = ctx.layout(self.view_id, constraint, app);
312 self.size = Some(size);
313 size
314 }
315
316 fn after_layout(&mut self, ctx: &mut AfterLayoutContext, app: &mut MutableAppContext) {
317 ctx.after_layout(self.view_id, app);
318 }
319
320 fn paint(&mut self, origin: Vector2F, ctx: &mut PaintContext, app: &AppContext) {
321 self.origin = Some(origin);
322 ctx.paint(self.view_id, origin, app);
323 }
324
325 fn dispatch_event(&self, event: &Event, ctx: &mut EventContext, app: &AppContext) -> bool {
326 ctx.dispatch_event_on_view(self.view_id, event, app)
327 }
328
329 fn size(&self) -> Option<Vector2F> {
330 self.size
331 }
332}
333
334#[cfg(test)]
335mod tests {
336 // #[test]
337 // fn test_responder_chain() {
338 // let settings = settings_rx(None);
339 // let mut app = App::new().unwrap();
340 // let workspace = app.add_model(|ctx| Workspace::new(Vec::new(), ctx));
341 // let (window_id, workspace_view) =
342 // app.add_window(|ctx| WorkspaceView::new(workspace.clone(), settings, ctx));
343
344 // let invalidations = Rc::new(RefCell::new(Vec::new()));
345 // let invalidations_ = invalidations.clone();
346 // app.on_window_invalidated(window_id, move |invalidation, _| {
347 // invalidations_.borrow_mut().push(invalidation)
348 // });
349
350 // let active_pane_id = workspace_view.update(&mut app, |view, ctx| {
351 // ctx.focus(view.active_pane());
352 // view.active_pane().id()
353 // });
354
355 // app.update(|app| {
356 // let mut presenter = Presenter::new(
357 // window_id,
358 // Rc::new(FontCache::new()),
359 // Rc::new(AssetCache::new()),
360 // app,
361 // );
362 // for invalidation in invalidations.borrow().iter().cloned() {
363 // presenter.update(vec2f(1024.0, 768.0), 2.0, Some(invalidation), app);
364 // }
365
366 // assert_eq!(
367 // presenter.responder_chain(app.ctx()).unwrap(),
368 // vec![workspace_view.id(), active_pane_id]
369 // );
370 // });
371 // }
372}