1use crate::{
2 app::{AppContext, MutableAppContext, WindowInvalidation},
3 elements::Element,
4 font_cache::FontCache,
5 geometry::rect::RectF,
6 json::{self, ToJson},
7 keymap::Keystroke,
8 platform::{CursorStyle, Event},
9 text_layout::TextLayoutCache,
10 Action, AnyModelHandle, AnyViewHandle, AnyWeakModelHandle, AssetCache, ElementBox,
11 ElementStateContext, Entity, FontSystem, ModelHandle, ReadModel, ReadView, Scene,
12 UpgradeModelHandle, UpgradeViewHandle, View, ViewHandle, WeakModelHandle, WeakViewHandle,
13};
14use pathfinder_geometry::vector::{vec2f, Vector2F};
15use serde_json::json;
16use smallvec::SmallVec;
17use std::{
18 collections::{HashMap, HashSet},
19 ops::{Deref, DerefMut},
20 sync::Arc,
21};
22
23pub struct Presenter {
24 window_id: usize,
25 pub(crate) rendered_views: HashMap<usize, ElementBox>,
26 parents: HashMap<usize, usize>,
27 cursor_styles: Vec<(RectF, CursorStyle)>,
28 font_cache: Arc<FontCache>,
29 text_layout_cache: TextLayoutCache,
30 asset_cache: Arc<AssetCache>,
31 last_mouse_moved_event: Option<Event>,
32 titlebar_height: f32,
33}
34
35impl Presenter {
36 pub fn new(
37 window_id: usize,
38 titlebar_height: f32,
39 font_cache: Arc<FontCache>,
40 text_layout_cache: TextLayoutCache,
41 asset_cache: Arc<AssetCache>,
42 cx: &mut MutableAppContext,
43 ) -> Self {
44 Self {
45 window_id,
46 rendered_views: cx.render_views(window_id, titlebar_height),
47 parents: HashMap::new(),
48 cursor_styles: Default::default(),
49 font_cache,
50 text_layout_cache,
51 asset_cache,
52 last_mouse_moved_event: None,
53 titlebar_height,
54 }
55 }
56
57 pub fn dispatch_path(&self, app: &AppContext) -> Vec<usize> {
58 if let Some(view_id) = app.focused_view_id(self.window_id) {
59 self.dispatch_path_from(view_id)
60 } else {
61 Vec::new()
62 }
63 }
64
65 pub(crate) fn dispatch_path_from(&self, mut view_id: usize) -> Vec<usize> {
66 let mut path = Vec::new();
67 path.push(view_id);
68 while let Some(parent_id) = self.parents.get(&view_id).copied() {
69 path.push(parent_id);
70 view_id = parent_id;
71 }
72 path.reverse();
73 path
74 }
75
76 pub fn invalidate(
77 &mut self,
78 invalidation: &mut WindowInvalidation,
79 cx: &mut MutableAppContext,
80 ) {
81 cx.start_frame();
82 for view_id in &invalidation.removed {
83 invalidation.updated.remove(&view_id);
84 self.rendered_views.remove(&view_id);
85 self.parents.remove(&view_id);
86 }
87 for view_id in &invalidation.updated {
88 self.rendered_views.insert(
89 *view_id,
90 cx.render_view(self.window_id, *view_id, self.titlebar_height, false)
91 .unwrap(),
92 );
93 }
94 }
95
96 pub fn refresh(&mut self, invalidation: &mut WindowInvalidation, cx: &mut MutableAppContext) {
97 self.invalidate(invalidation, cx);
98 for (view_id, view) in &mut self.rendered_views {
99 if !invalidation.updated.contains(view_id) {
100 *view = cx
101 .render_view(self.window_id, *view_id, self.titlebar_height, true)
102 .unwrap();
103 }
104 }
105 }
106
107 pub fn build_scene(
108 &mut self,
109 window_size: Vector2F,
110 scale_factor: f32,
111 refreshing: bool,
112 cx: &mut MutableAppContext,
113 ) -> Scene {
114 let mut scene = Scene::new(scale_factor);
115
116 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
117 self.layout(window_size, refreshing, cx);
118 let mut paint_cx = self.build_paint_context(&mut scene, cx);
119 paint_cx.paint(
120 root_view_id,
121 Vector2F::zero(),
122 RectF::new(Vector2F::zero(), window_size),
123 );
124 self.text_layout_cache.finish_frame();
125 self.cursor_styles = scene.cursor_styles();
126
127 if cx.window_is_active(self.window_id) {
128 if let Some(event) = self.last_mouse_moved_event.clone() {
129 self.dispatch_event(event, cx)
130 }
131 }
132 } else {
133 log::error!("could not find root_view_id for window {}", self.window_id);
134 }
135
136 scene
137 }
138
139 fn layout(&mut self, window_size: Vector2F, refreshing: bool, cx: &mut MutableAppContext) {
140 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
141 self.build_layout_context(window_size, refreshing, cx)
142 .layout(root_view_id, SizeConstraint::strict(window_size));
143 }
144 }
145
146 pub fn build_layout_context<'a>(
147 &'a mut self,
148 window_size: Vector2F,
149 refreshing: bool,
150 cx: &'a mut MutableAppContext,
151 ) -> LayoutContext<'a> {
152 LayoutContext {
153 window_id: self.window_id,
154 rendered_views: &mut self.rendered_views,
155 parents: &mut self.parents,
156 refreshing,
157 window_size,
158 font_cache: &self.font_cache,
159 font_system: cx.platform().fonts(),
160 text_layout_cache: &self.text_layout_cache,
161 asset_cache: &self.asset_cache,
162 view_stack: Vec::new(),
163 app: cx,
164 }
165 }
166
167 pub fn build_paint_context<'a>(
168 &'a mut self,
169 scene: &'a mut Scene,
170 cx: &'a mut MutableAppContext,
171 ) -> PaintContext {
172 PaintContext {
173 scene,
174 font_cache: &self.font_cache,
175 text_layout_cache: &self.text_layout_cache,
176 rendered_views: &mut self.rendered_views,
177 app: cx,
178 }
179 }
180
181 pub fn dispatch_event(&mut self, event: Event, cx: &mut MutableAppContext) {
182 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
183 match event {
184 Event::MouseMoved {
185 position,
186 left_mouse_down,
187 } => {
188 self.last_mouse_moved_event = Some(event.clone());
189
190 if !left_mouse_down {
191 let mut style_to_assign = CursorStyle::Arrow;
192 for (bounds, style) in self.cursor_styles.iter().rev() {
193 if bounds.contains_point(position) {
194 style_to_assign = *style;
195 break;
196 }
197 }
198 cx.platform().set_cursor_style(style_to_assign);
199 }
200 }
201 Event::LeftMouseDragged { position } => {
202 self.last_mouse_moved_event = Some(Event::MouseMoved {
203 position,
204 left_mouse_down: true,
205 });
206 }
207 _ => {}
208 }
209
210 let mut event_cx = self.build_event_context(cx);
211 event_cx.dispatch_event(root_view_id, &event);
212
213 let invalidated_views = event_cx.invalidated_views;
214 let dispatch_directives = event_cx.dispatched_actions;
215
216 for view_id in invalidated_views {
217 cx.notify_view(self.window_id, view_id);
218 }
219 for directive in dispatch_directives {
220 cx.dispatch_action_any(self.window_id, &directive.path, directive.action.as_ref());
221 }
222 }
223 }
224
225 pub fn build_event_context<'a>(
226 &'a mut self,
227 cx: &'a mut MutableAppContext,
228 ) -> EventContext<'a> {
229 EventContext {
230 rendered_views: &mut self.rendered_views,
231 dispatched_actions: Default::default(),
232 font_cache: &self.font_cache,
233 text_layout_cache: &self.text_layout_cache,
234 view_stack: Default::default(),
235 invalidated_views: Default::default(),
236 notify_count: 0,
237 app: cx,
238 }
239 }
240
241 pub fn debug_elements(&self, cx: &AppContext) -> Option<json::Value> {
242 let view = cx.root_view(self.window_id)?;
243 Some(json!({
244 "root_view": view.debug_json(cx),
245 "root_element": self.rendered_views.get(&view.id())
246 .map(|root_element| {
247 root_element.debug(&DebugContext {
248 rendered_views: &self.rendered_views,
249 font_cache: &self.font_cache,
250 app: cx,
251 })
252 })
253 }))
254 }
255}
256
257pub struct DispatchDirective {
258 pub path: Vec<usize>,
259 pub action: Box<dyn Action>,
260}
261
262pub struct LayoutContext<'a> {
263 window_id: usize,
264 rendered_views: &'a mut HashMap<usize, ElementBox>,
265 parents: &'a mut HashMap<usize, usize>,
266 view_stack: Vec<usize>,
267 pub refreshing: bool,
268 pub window_size: Vector2F,
269 pub font_cache: &'a Arc<FontCache>,
270 pub font_system: Arc<dyn FontSystem>,
271 pub text_layout_cache: &'a TextLayoutCache,
272 pub asset_cache: &'a AssetCache,
273 pub app: &'a mut MutableAppContext,
274}
275
276impl<'a> LayoutContext<'a> {
277 fn layout(&mut self, view_id: usize, constraint: SizeConstraint) -> Vector2F {
278 if let Some(parent_id) = self.view_stack.last() {
279 self.parents.insert(view_id, *parent_id);
280 }
281 self.view_stack.push(view_id);
282 let mut rendered_view = self.rendered_views.remove(&view_id).unwrap();
283 let size = rendered_view.layout(constraint, self);
284 self.rendered_views.insert(view_id, rendered_view);
285 self.view_stack.pop();
286 size
287 }
288
289 pub(crate) fn keystrokes_for_action(
290 &self,
291 action: &dyn Action,
292 ) -> Option<SmallVec<[Keystroke; 2]>> {
293 self.app
294 .keystrokes_for_action(self.window_id, &self.view_stack, action)
295 }
296}
297
298impl<'a> Deref for LayoutContext<'a> {
299 type Target = MutableAppContext;
300
301 fn deref(&self) -> &Self::Target {
302 self.app
303 }
304}
305
306impl<'a> DerefMut for LayoutContext<'a> {
307 fn deref_mut(&mut self) -> &mut Self::Target {
308 self.app
309 }
310}
311
312impl<'a> ReadView for LayoutContext<'a> {
313 fn read_view<T: View>(&self, handle: &ViewHandle<T>) -> &T {
314 self.app.read_view(handle)
315 }
316}
317
318impl<'a> ReadModel for LayoutContext<'a> {
319 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
320 self.app.read_model(handle)
321 }
322}
323
324impl<'a> UpgradeModelHandle for LayoutContext<'a> {
325 fn upgrade_model_handle<T: Entity>(
326 &self,
327 handle: &WeakModelHandle<T>,
328 ) -> Option<ModelHandle<T>> {
329 self.app.upgrade_model_handle(handle)
330 }
331
332 fn model_handle_is_upgradable<T: Entity>(&self, handle: &WeakModelHandle<T>) -> bool {
333 self.app.model_handle_is_upgradable(handle)
334 }
335
336 fn upgrade_any_model_handle(&self, handle: &AnyWeakModelHandle) -> Option<AnyModelHandle> {
337 self.app.upgrade_any_model_handle(handle)
338 }
339}
340
341impl<'a> UpgradeViewHandle for LayoutContext<'a> {
342 fn upgrade_view_handle<T: View>(&self, handle: &WeakViewHandle<T>) -> Option<ViewHandle<T>> {
343 self.app.upgrade_view_handle(handle)
344 }
345
346 fn upgrade_any_view_handle(&self, handle: &crate::AnyWeakViewHandle) -> Option<AnyViewHandle> {
347 self.app.upgrade_any_view_handle(handle)
348 }
349}
350
351impl<'a> ElementStateContext for LayoutContext<'a> {
352 fn current_view_id(&self) -> usize {
353 *self.view_stack.last().unwrap()
354 }
355}
356
357pub struct PaintContext<'a> {
358 rendered_views: &'a mut HashMap<usize, ElementBox>,
359 pub scene: &'a mut Scene,
360 pub font_cache: &'a FontCache,
361 pub text_layout_cache: &'a TextLayoutCache,
362 pub app: &'a AppContext,
363}
364
365impl<'a> PaintContext<'a> {
366 fn paint(&mut self, view_id: usize, origin: Vector2F, visible_bounds: RectF) {
367 if let Some(mut tree) = self.rendered_views.remove(&view_id) {
368 tree.paint(origin, visible_bounds, self);
369 self.rendered_views.insert(view_id, tree);
370 }
371 }
372}
373
374impl<'a> Deref for PaintContext<'a> {
375 type Target = AppContext;
376
377 fn deref(&self) -> &Self::Target {
378 self.app
379 }
380}
381
382pub struct EventContext<'a> {
383 rendered_views: &'a mut HashMap<usize, ElementBox>,
384 dispatched_actions: Vec<DispatchDirective>,
385 pub font_cache: &'a FontCache,
386 pub text_layout_cache: &'a TextLayoutCache,
387 pub app: &'a mut MutableAppContext,
388 pub notify_count: usize,
389 view_stack: Vec<usize>,
390 invalidated_views: HashSet<usize>,
391}
392
393impl<'a> EventContext<'a> {
394 fn dispatch_event(&mut self, view_id: usize, event: &Event) -> bool {
395 if let Some(mut element) = self.rendered_views.remove(&view_id) {
396 self.view_stack.push(view_id);
397 let result = element.dispatch_event(event, self);
398 self.view_stack.pop();
399 self.rendered_views.insert(view_id, element);
400 result
401 } else {
402 false
403 }
404 }
405
406 pub fn dispatch_any_action(&mut self, action: Box<dyn Action>) {
407 self.dispatched_actions.push(DispatchDirective {
408 path: self.view_stack.clone(),
409 action,
410 });
411 }
412
413 pub fn dispatch_action<A: Action>(&mut self, action: A) {
414 self.dispatch_any_action(Box::new(action));
415 }
416
417 pub fn notify(&mut self) {
418 self.notify_count += 1;
419 if let Some(view_id) = self.view_stack.last() {
420 self.invalidated_views.insert(*view_id);
421 }
422 }
423
424 pub fn notify_count(&self) -> usize {
425 self.notify_count
426 }
427}
428
429impl<'a> Deref for EventContext<'a> {
430 type Target = MutableAppContext;
431
432 fn deref(&self) -> &Self::Target {
433 self.app
434 }
435}
436
437impl<'a> DerefMut for EventContext<'a> {
438 fn deref_mut(&mut self) -> &mut Self::Target {
439 self.app
440 }
441}
442
443pub struct DebugContext<'a> {
444 rendered_views: &'a HashMap<usize, ElementBox>,
445 pub font_cache: &'a FontCache,
446 pub app: &'a AppContext,
447}
448
449#[derive(Clone, Copy, Debug, Eq, PartialEq)]
450pub enum Axis {
451 Horizontal,
452 Vertical,
453}
454
455impl Axis {
456 pub fn invert(self) -> Self {
457 match self {
458 Self::Horizontal => Self::Vertical,
459 Self::Vertical => Self::Horizontal,
460 }
461 }
462}
463
464impl ToJson for Axis {
465 fn to_json(&self) -> serde_json::Value {
466 match self {
467 Axis::Horizontal => json!("horizontal"),
468 Axis::Vertical => json!("vertical"),
469 }
470 }
471}
472
473pub trait Vector2FExt {
474 fn along(self, axis: Axis) -> f32;
475}
476
477impl Vector2FExt for Vector2F {
478 fn along(self, axis: Axis) -> f32 {
479 match axis {
480 Axis::Horizontal => self.x(),
481 Axis::Vertical => self.y(),
482 }
483 }
484}
485
486#[derive(Copy, Clone, Debug)]
487pub struct SizeConstraint {
488 pub min: Vector2F,
489 pub max: Vector2F,
490}
491
492impl SizeConstraint {
493 pub fn new(min: Vector2F, max: Vector2F) -> Self {
494 Self { min, max }
495 }
496
497 pub fn strict(size: Vector2F) -> Self {
498 Self {
499 min: size,
500 max: size,
501 }
502 }
503
504 pub fn strict_along(axis: Axis, max: f32) -> Self {
505 match axis {
506 Axis::Horizontal => Self {
507 min: vec2f(max, 0.0),
508 max: vec2f(max, f32::INFINITY),
509 },
510 Axis::Vertical => Self {
511 min: vec2f(0.0, max),
512 max: vec2f(f32::INFINITY, max),
513 },
514 }
515 }
516
517 pub fn max_along(&self, axis: Axis) -> f32 {
518 match axis {
519 Axis::Horizontal => self.max.x(),
520 Axis::Vertical => self.max.y(),
521 }
522 }
523
524 pub fn min_along(&self, axis: Axis) -> f32 {
525 match axis {
526 Axis::Horizontal => self.min.x(),
527 Axis::Vertical => self.min.y(),
528 }
529 }
530
531 pub fn constrain(&self, size: Vector2F) -> Vector2F {
532 vec2f(
533 size.x().min(self.max.x()).max(self.min.x()),
534 size.y().min(self.max.y()).max(self.min.y()),
535 )
536 }
537}
538
539impl Default for SizeConstraint {
540 fn default() -> Self {
541 SizeConstraint {
542 min: Vector2F::zero(),
543 max: Vector2F::splat(f32::INFINITY),
544 }
545 }
546}
547
548impl ToJson for SizeConstraint {
549 fn to_json(&self) -> serde_json::Value {
550 json!({
551 "min": self.min.to_json(),
552 "max": self.max.to_json(),
553 })
554 }
555}
556
557pub struct ChildView {
558 view: AnyViewHandle,
559}
560
561impl ChildView {
562 pub fn new(view: impl Into<AnyViewHandle>) -> Self {
563 Self { view: view.into() }
564 }
565}
566
567impl Element for ChildView {
568 type LayoutState = ();
569 type PaintState = ();
570
571 fn layout(
572 &mut self,
573 constraint: SizeConstraint,
574 cx: &mut LayoutContext,
575 ) -> (Vector2F, Self::LayoutState) {
576 let size = cx.layout(self.view.id(), constraint);
577 (size, ())
578 }
579
580 fn paint(
581 &mut self,
582 bounds: RectF,
583 visible_bounds: RectF,
584 _: &mut Self::LayoutState,
585 cx: &mut PaintContext,
586 ) -> Self::PaintState {
587 cx.paint(self.view.id(), bounds.origin(), visible_bounds);
588 }
589
590 fn dispatch_event(
591 &mut self,
592 event: &Event,
593 _: RectF,
594 _: RectF,
595 _: &mut Self::LayoutState,
596 _: &mut Self::PaintState,
597 cx: &mut EventContext,
598 ) -> bool {
599 cx.dispatch_event(self.view.id(), event)
600 }
601
602 fn debug(
603 &self,
604 bounds: RectF,
605 _: &Self::LayoutState,
606 _: &Self::PaintState,
607 cx: &DebugContext,
608 ) -> serde_json::Value {
609 json!({
610 "type": "ChildView",
611 "view_id": self.view.id(),
612 "bounds": bounds.to_json(),
613 "view": self.view.debug_json(cx.app),
614 "child": if let Some(view) = cx.rendered_views.get(&self.view.id()) {
615 view.debug(cx)
616 } else {
617 json!(null)
618 }
619 })
620 }
621}