1use crate::{
2 app::{AppContext, MutableAppContext, WindowInvalidation},
3 elements::Element,
4 font_cache::FontCache,
5 geometry::rect::RectF,
6 json::{self, ToJson},
7 platform::Event,
8 text_layout::TextLayoutCache,
9 Action, AnyAction, AnyModelHandle, AnyViewHandle, AnyWeakModelHandle, AssetCache, ElementBox,
10 ElementStateContext, Entity, FontSystem, ModelHandle, ReadModel, ReadView, Scene,
11 UpgradeModelHandle, UpgradeViewHandle, View, ViewHandle, WeakModelHandle, WeakViewHandle,
12};
13use pathfinder_geometry::vector::{vec2f, Vector2F};
14use serde_json::json;
15use std::{
16 collections::{HashMap, HashSet},
17 ops::{Deref, DerefMut},
18 sync::Arc,
19};
20
21pub struct Presenter {
22 window_id: usize,
23 rendered_views: HashMap<usize, ElementBox>,
24 parents: HashMap<usize, usize>,
25 font_cache: Arc<FontCache>,
26 text_layout_cache: TextLayoutCache,
27 asset_cache: Arc<AssetCache>,
28 last_mouse_moved_event: Option<Event>,
29 titlebar_height: f32,
30}
31
32impl Presenter {
33 pub fn new(
34 window_id: usize,
35 titlebar_height: f32,
36 font_cache: Arc<FontCache>,
37 text_layout_cache: TextLayoutCache,
38 asset_cache: Arc<AssetCache>,
39 cx: &mut MutableAppContext,
40 ) -> Self {
41 Self {
42 window_id,
43 rendered_views: cx.render_views(window_id, titlebar_height),
44 parents: HashMap::new(),
45 font_cache,
46 text_layout_cache,
47 asset_cache,
48 last_mouse_moved_event: None,
49 titlebar_height,
50 }
51 }
52
53 pub fn dispatch_path(&self, app: &AppContext) -> Vec<usize> {
54 let mut path = Vec::new();
55 if let Some(mut view_id) = app.focused_view_id(self.window_id) {
56 path.push(view_id);
57 while let Some(parent_id) = self.parents.get(&view_id).copied() {
58 path.push(parent_id);
59 view_id = parent_id;
60 }
61 path.reverse();
62 }
63 path
64 }
65
66 pub fn invalidate(&mut self, mut invalidation: WindowInvalidation, cx: &mut MutableAppContext) {
67 cx.start_frame();
68 for view_id in invalidation.removed {
69 invalidation.updated.remove(&view_id);
70 self.rendered_views.remove(&view_id);
71 self.parents.remove(&view_id);
72 }
73 for view_id in invalidation.updated {
74 self.rendered_views.insert(
75 view_id,
76 cx.render_view(self.window_id, view_id, self.titlebar_height, false)
77 .unwrap(),
78 );
79 }
80 }
81
82 pub fn refresh(
83 &mut self,
84 invalidation: Option<WindowInvalidation>,
85 cx: &mut MutableAppContext,
86 ) {
87 cx.start_frame();
88 if let Some(invalidation) = invalidation {
89 for view_id in invalidation.removed {
90 self.rendered_views.remove(&view_id);
91 self.parents.remove(&view_id);
92 }
93 }
94
95 for (view_id, view) in &mut self.rendered_views {
96 *view = cx
97 .render_view(self.window_id, *view_id, self.titlebar_height, true)
98 .unwrap();
99 }
100 }
101
102 pub fn build_scene(
103 &mut self,
104 window_size: Vector2F,
105 scale_factor: f32,
106 refreshing: bool,
107 cx: &mut MutableAppContext,
108 ) -> Scene {
109 let mut scene = Scene::new(scale_factor);
110
111 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
112 self.layout(window_size, refreshing, cx);
113 let mut paint_cx = self.build_paint_context(&mut scene, cx);
114 paint_cx.paint(
115 root_view_id,
116 Vector2F::zero(),
117 RectF::new(Vector2F::zero(), window_size),
118 );
119 self.text_layout_cache.finish_frame();
120
121 if let Some(event) = self.last_mouse_moved_event.clone() {
122 self.dispatch_event(event, cx)
123 }
124 } else {
125 log::error!("could not find root_view_id for window {}", self.window_id);
126 }
127
128 scene
129 }
130
131 fn layout(&mut self, size: Vector2F, refreshing: bool, cx: &mut MutableAppContext) {
132 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
133 self.build_layout_context(refreshing, cx)
134 .layout(root_view_id, SizeConstraint::strict(size));
135 }
136 }
137
138 pub fn build_layout_context<'a>(
139 &'a mut self,
140 refreshing: bool,
141 cx: &'a mut MutableAppContext,
142 ) -> LayoutContext<'a> {
143 LayoutContext {
144 rendered_views: &mut self.rendered_views,
145 parents: &mut self.parents,
146 refreshing,
147 font_cache: &self.font_cache,
148 font_system: cx.platform().fonts(),
149 text_layout_cache: &self.text_layout_cache,
150 asset_cache: &self.asset_cache,
151 view_stack: Vec::new(),
152 app: cx,
153 }
154 }
155
156 pub fn build_paint_context<'a>(
157 &'a mut self,
158 scene: &'a mut Scene,
159 cx: &'a mut MutableAppContext,
160 ) -> PaintContext {
161 PaintContext {
162 scene,
163 font_cache: &self.font_cache,
164 text_layout_cache: &self.text_layout_cache,
165 rendered_views: &mut self.rendered_views,
166 app: cx,
167 }
168 }
169
170 pub fn dispatch_event(&mut self, event: Event, cx: &mut MutableAppContext) {
171 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
172 match event {
173 Event::MouseMoved { .. } => {
174 self.last_mouse_moved_event = Some(event.clone());
175 }
176 Event::LeftMouseDragged { position } => {
177 self.last_mouse_moved_event = Some(Event::MouseMoved {
178 position,
179 left_mouse_down: true,
180 });
181 }
182 _ => {}
183 }
184
185 let mut event_cx = self.build_event_context(cx);
186 event_cx.dispatch_event(root_view_id, &event);
187
188 let invalidated_views = event_cx.invalidated_views;
189 let dispatch_directives = event_cx.dispatched_actions;
190
191 for view_id in invalidated_views {
192 cx.notify_view(self.window_id, view_id);
193 }
194 for directive in dispatch_directives {
195 cx.dispatch_action_any(self.window_id, &directive.path, directive.action.as_ref());
196 }
197 }
198 }
199
200 pub fn build_event_context<'a>(
201 &'a mut self,
202 cx: &'a mut MutableAppContext,
203 ) -> EventContext<'a> {
204 EventContext {
205 rendered_views: &mut self.rendered_views,
206 dispatched_actions: Default::default(),
207 font_cache: &self.font_cache,
208 text_layout_cache: &self.text_layout_cache,
209 view_stack: Default::default(),
210 invalidated_views: Default::default(),
211 notify_count: 0,
212 app: cx,
213 }
214 }
215
216 pub fn debug_elements(&self, cx: &AppContext) -> Option<json::Value> {
217 cx.root_view_id(self.window_id)
218 .and_then(|root_view_id| self.rendered_views.get(&root_view_id))
219 .map(|root_element| {
220 root_element.debug(&DebugContext {
221 rendered_views: &self.rendered_views,
222 font_cache: &self.font_cache,
223 app: cx,
224 })
225 })
226 }
227}
228
229pub struct DispatchDirective {
230 pub path: Vec<usize>,
231 pub action: Box<dyn AnyAction>,
232}
233
234pub struct LayoutContext<'a> {
235 rendered_views: &'a mut HashMap<usize, ElementBox>,
236 parents: &'a mut HashMap<usize, usize>,
237 view_stack: Vec<usize>,
238 pub refreshing: bool,
239 pub font_cache: &'a Arc<FontCache>,
240 pub font_system: Arc<dyn FontSystem>,
241 pub text_layout_cache: &'a TextLayoutCache,
242 pub asset_cache: &'a AssetCache,
243 pub app: &'a mut MutableAppContext,
244}
245
246impl<'a> LayoutContext<'a> {
247 fn layout(&mut self, view_id: usize, constraint: SizeConstraint) -> Vector2F {
248 if let Some(parent_id) = self.view_stack.last() {
249 self.parents.insert(view_id, *parent_id);
250 }
251 self.view_stack.push(view_id);
252 let mut rendered_view = self.rendered_views.remove(&view_id).unwrap();
253 let size = rendered_view.layout(constraint, self);
254 self.rendered_views.insert(view_id, rendered_view);
255 self.view_stack.pop();
256 size
257 }
258}
259
260impl<'a> Deref for LayoutContext<'a> {
261 type Target = MutableAppContext;
262
263 fn deref(&self) -> &Self::Target {
264 self.app
265 }
266}
267
268impl<'a> DerefMut for LayoutContext<'a> {
269 fn deref_mut(&mut self) -> &mut Self::Target {
270 self.app
271 }
272}
273
274impl<'a> ReadView for LayoutContext<'a> {
275 fn read_view<T: View>(&self, handle: &ViewHandle<T>) -> &T {
276 self.app.read_view(handle)
277 }
278}
279
280impl<'a> ReadModel for LayoutContext<'a> {
281 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
282 self.app.read_model(handle)
283 }
284}
285
286impl<'a> UpgradeModelHandle for LayoutContext<'a> {
287 fn upgrade_model_handle<T: Entity>(
288 &self,
289 handle: &WeakModelHandle<T>,
290 ) -> Option<ModelHandle<T>> {
291 self.app.upgrade_model_handle(handle)
292 }
293
294 fn model_handle_is_upgradable<T: Entity>(&self, handle: &WeakModelHandle<T>) -> bool {
295 self.app.model_handle_is_upgradable(handle)
296 }
297
298 fn upgrade_any_model_handle(&self, handle: &AnyWeakModelHandle) -> Option<AnyModelHandle> {
299 self.app.upgrade_any_model_handle(handle)
300 }
301}
302
303impl<'a> UpgradeViewHandle for LayoutContext<'a> {
304 fn upgrade_view_handle<T: View>(&self, handle: &WeakViewHandle<T>) -> Option<ViewHandle<T>> {
305 self.app.upgrade_view_handle(handle)
306 }
307}
308
309impl<'a> ElementStateContext for LayoutContext<'a> {
310 fn current_view_id(&self) -> usize {
311 *self.view_stack.last().unwrap()
312 }
313}
314
315pub struct PaintContext<'a> {
316 rendered_views: &'a mut HashMap<usize, ElementBox>,
317 pub scene: &'a mut Scene,
318 pub font_cache: &'a FontCache,
319 pub text_layout_cache: &'a TextLayoutCache,
320 pub app: &'a AppContext,
321}
322
323impl<'a> PaintContext<'a> {
324 fn paint(&mut self, view_id: usize, origin: Vector2F, visible_bounds: RectF) {
325 if let Some(mut tree) = self.rendered_views.remove(&view_id) {
326 tree.paint(origin, visible_bounds, self);
327 self.rendered_views.insert(view_id, tree);
328 }
329 }
330}
331
332impl<'a> Deref for PaintContext<'a> {
333 type Target = AppContext;
334
335 fn deref(&self) -> &Self::Target {
336 self.app
337 }
338}
339
340pub struct EventContext<'a> {
341 rendered_views: &'a mut HashMap<usize, ElementBox>,
342 dispatched_actions: Vec<DispatchDirective>,
343 pub font_cache: &'a FontCache,
344 pub text_layout_cache: &'a TextLayoutCache,
345 pub app: &'a mut MutableAppContext,
346 pub notify_count: usize,
347 view_stack: Vec<usize>,
348 invalidated_views: HashSet<usize>,
349}
350
351impl<'a> EventContext<'a> {
352 fn dispatch_event(&mut self, view_id: usize, event: &Event) -> bool {
353 if let Some(mut element) = self.rendered_views.remove(&view_id) {
354 self.view_stack.push(view_id);
355 let result = element.dispatch_event(event, self);
356 self.view_stack.pop();
357 self.rendered_views.insert(view_id, element);
358 result
359 } else {
360 false
361 }
362 }
363
364 pub fn dispatch_action<A: Action>(&mut self, action: A) {
365 self.dispatched_actions.push(DispatchDirective {
366 path: self.view_stack.clone(),
367 action: Box::new(action),
368 });
369 }
370
371 pub fn notify(&mut self) {
372 self.notify_count += 1;
373 if let Some(view_id) = self.view_stack.last() {
374 self.invalidated_views.insert(*view_id);
375 }
376 }
377
378 pub fn notify_count(&self) -> usize {
379 self.notify_count
380 }
381}
382
383impl<'a> Deref for EventContext<'a> {
384 type Target = MutableAppContext;
385
386 fn deref(&self) -> &Self::Target {
387 self.app
388 }
389}
390
391impl<'a> DerefMut for EventContext<'a> {
392 fn deref_mut(&mut self) -> &mut Self::Target {
393 self.app
394 }
395}
396
397pub struct DebugContext<'a> {
398 rendered_views: &'a HashMap<usize, ElementBox>,
399 pub font_cache: &'a FontCache,
400 pub app: &'a AppContext,
401}
402
403#[derive(Clone, Copy, Debug, Eq, PartialEq)]
404pub enum Axis {
405 Horizontal,
406 Vertical,
407}
408
409impl Axis {
410 pub fn invert(self) -> Self {
411 match self {
412 Self::Horizontal => Self::Vertical,
413 Self::Vertical => Self::Horizontal,
414 }
415 }
416}
417
418impl ToJson for Axis {
419 fn to_json(&self) -> serde_json::Value {
420 match self {
421 Axis::Horizontal => json!("horizontal"),
422 Axis::Vertical => json!("vertical"),
423 }
424 }
425}
426
427pub trait Vector2FExt {
428 fn along(self, axis: Axis) -> f32;
429}
430
431impl Vector2FExt for Vector2F {
432 fn along(self, axis: Axis) -> f32 {
433 match axis {
434 Axis::Horizontal => self.x(),
435 Axis::Vertical => self.y(),
436 }
437 }
438}
439
440#[derive(Copy, Clone, Debug)]
441pub struct SizeConstraint {
442 pub min: Vector2F,
443 pub max: Vector2F,
444}
445
446impl SizeConstraint {
447 pub fn new(min: Vector2F, max: Vector2F) -> Self {
448 Self { min, max }
449 }
450
451 pub fn strict(size: Vector2F) -> Self {
452 Self {
453 min: size,
454 max: size,
455 }
456 }
457
458 pub fn strict_along(axis: Axis, max: f32) -> Self {
459 match axis {
460 Axis::Horizontal => Self {
461 min: vec2f(max, 0.0),
462 max: vec2f(max, f32::INFINITY),
463 },
464 Axis::Vertical => Self {
465 min: vec2f(0.0, max),
466 max: vec2f(f32::INFINITY, max),
467 },
468 }
469 }
470
471 pub fn max_along(&self, axis: Axis) -> f32 {
472 match axis {
473 Axis::Horizontal => self.max.x(),
474 Axis::Vertical => self.max.y(),
475 }
476 }
477
478 pub fn min_along(&self, axis: Axis) -> f32 {
479 match axis {
480 Axis::Horizontal => self.min.x(),
481 Axis::Vertical => self.min.y(),
482 }
483 }
484
485 pub fn constrain(&self, size: Vector2F) -> Vector2F {
486 vec2f(
487 size.x().min(self.max.x()).max(self.min.x()),
488 size.y().min(self.max.y()).max(self.min.y()),
489 )
490 }
491}
492
493impl ToJson for SizeConstraint {
494 fn to_json(&self) -> serde_json::Value {
495 json!({
496 "min": self.min.to_json(),
497 "max": self.max.to_json(),
498 })
499 }
500}
501
502pub struct ChildView {
503 view: AnyViewHandle,
504}
505
506impl ChildView {
507 pub fn new(view: impl Into<AnyViewHandle>) -> Self {
508 Self { view: view.into() }
509 }
510}
511
512impl Element for ChildView {
513 type LayoutState = ();
514 type PaintState = ();
515
516 fn layout(
517 &mut self,
518 constraint: SizeConstraint,
519 cx: &mut LayoutContext,
520 ) -> (Vector2F, Self::LayoutState) {
521 let size = cx.layout(self.view.id(), constraint);
522 (size, ())
523 }
524
525 fn paint(
526 &mut self,
527 bounds: RectF,
528 visible_bounds: RectF,
529 _: &mut Self::LayoutState,
530 cx: &mut PaintContext,
531 ) -> Self::PaintState {
532 cx.paint(self.view.id(), bounds.origin(), visible_bounds);
533 }
534
535 fn dispatch_event(
536 &mut self,
537 event: &Event,
538 _: RectF,
539 _: &mut Self::LayoutState,
540 _: &mut Self::PaintState,
541 cx: &mut EventContext,
542 ) -> bool {
543 cx.dispatch_event(self.view.id(), event)
544 }
545
546 fn debug(
547 &self,
548 bounds: RectF,
549 _: &Self::LayoutState,
550 _: &Self::PaintState,
551 cx: &DebugContext,
552 ) -> serde_json::Value {
553 json!({
554 "type": "ChildView",
555 "view_id": self.view.id(),
556 "bounds": bounds.to_json(),
557 "child": if let Some(view) = cx.rendered_views.get(&self.view.id()) {
558 view.debug(cx)
559 } else {
560 json!(null)
561 }
562 })
563 }
564}