1pub mod actions;
2pub mod autoscroll;
3pub mod scroll_amount;
4
5use std::{
6 cmp::Ordering,
7 time::{Duration, Instant},
8};
9
10use gpui::{
11 geometry::vector::{vec2f, Vector2F},
12 AppContext, Axis, Task, ViewContext,
13};
14use language::{Bias, Point};
15use util::ResultExt;
16use workspace::{item::Item, WorkspaceId};
17
18use crate::{
19 display_map::{DisplaySnapshot, ToDisplayPoint},
20 hover_popover::hide_hover,
21 persistence::DB,
22 Anchor, DisplayPoint, Editor, EditorMode, Event, InlayRefreshReason, MultiBufferSnapshot,
23 ToPoint,
24};
25
26use self::{
27 autoscroll::{Autoscroll, AutoscrollStrategy},
28 scroll_amount::ScrollAmount,
29};
30
31pub const SCROLL_EVENT_SEPARATION: Duration = Duration::from_millis(28);
32const SCROLLBAR_SHOW_INTERVAL: Duration = Duration::from_secs(1);
33
34#[derive(Default)]
35pub struct ScrollbarAutoHide(pub bool);
36
37#[derive(Clone, Copy, Debug, PartialEq)]
38pub struct ScrollAnchor {
39 pub offset: Vector2F,
40 pub anchor: Anchor,
41}
42
43impl ScrollAnchor {
44 fn new() -> Self {
45 Self {
46 offset: Vector2F::zero(),
47 anchor: Anchor::min(),
48 }
49 }
50
51 pub fn scroll_position(&self, snapshot: &DisplaySnapshot) -> Vector2F {
52 let mut scroll_position = self.offset;
53 if self.anchor != Anchor::min() {
54 let scroll_top = self.anchor.to_display_point(snapshot).row() as f32;
55 scroll_position.set_y(scroll_top + scroll_position.y());
56 } else {
57 scroll_position.set_y(0.);
58 }
59 scroll_position
60 }
61
62 pub fn top_row(&self, buffer: &MultiBufferSnapshot) -> u32 {
63 self.anchor.to_point(buffer).row
64 }
65}
66
67#[derive(Clone, Copy, Debug)]
68pub struct OngoingScroll {
69 last_event: Instant,
70 axis: Option<Axis>,
71}
72
73impl OngoingScroll {
74 fn new() -> Self {
75 Self {
76 last_event: Instant::now() - SCROLL_EVENT_SEPARATION,
77 axis: None,
78 }
79 }
80
81 pub fn filter(&self, delta: &mut Vector2F) -> Option<Axis> {
82 const UNLOCK_PERCENT: f32 = 1.9;
83 const UNLOCK_LOWER_BOUND: f32 = 6.;
84 let mut axis = self.axis;
85
86 let x = delta.x().abs();
87 let y = delta.y().abs();
88 let duration = Instant::now().duration_since(self.last_event);
89 if duration > SCROLL_EVENT_SEPARATION {
90 //New ongoing scroll will start, determine axis
91 axis = if x <= y {
92 Some(Axis::Vertical)
93 } else {
94 Some(Axis::Horizontal)
95 };
96 } else if x.max(y) >= UNLOCK_LOWER_BOUND {
97 //Check if the current ongoing will need to unlock
98 match axis {
99 Some(Axis::Vertical) => {
100 if x > y && x >= y * UNLOCK_PERCENT {
101 axis = None;
102 }
103 }
104
105 Some(Axis::Horizontal) => {
106 if y > x && y >= x * UNLOCK_PERCENT {
107 axis = None;
108 }
109 }
110
111 None => {}
112 }
113 }
114
115 match axis {
116 Some(Axis::Vertical) => *delta = vec2f(0., delta.y()),
117 Some(Axis::Horizontal) => *delta = vec2f(delta.x(), 0.),
118 None => {}
119 }
120
121 axis
122 }
123}
124
125pub struct ScrollManager {
126 vertical_scroll_margin: f32,
127 anchor: ScrollAnchor,
128 ongoing: OngoingScroll,
129 autoscroll_request: Option<(Autoscroll, bool)>,
130 last_autoscroll: Option<(Vector2F, f32, f32, AutoscrollStrategy)>,
131 show_scrollbars: bool,
132 hide_scrollbar_task: Option<Task<()>>,
133 visible_line_count: Option<f32>,
134}
135
136impl ScrollManager {
137 pub fn new() -> Self {
138 ScrollManager {
139 vertical_scroll_margin: 3.0,
140 anchor: ScrollAnchor::new(),
141 ongoing: OngoingScroll::new(),
142 autoscroll_request: None,
143 show_scrollbars: true,
144 hide_scrollbar_task: None,
145 last_autoscroll: None,
146 visible_line_count: None,
147 }
148 }
149
150 pub fn clone_state(&mut self, other: &Self) {
151 self.anchor = other.anchor;
152 self.ongoing = other.ongoing;
153 }
154
155 pub fn anchor(&self) -> ScrollAnchor {
156 self.anchor
157 }
158
159 pub fn ongoing_scroll(&self) -> OngoingScroll {
160 self.ongoing
161 }
162
163 pub fn update_ongoing_scroll(&mut self, axis: Option<Axis>) {
164 self.ongoing.last_event = Instant::now();
165 self.ongoing.axis = axis;
166 }
167
168 pub fn scroll_position(&self, snapshot: &DisplaySnapshot) -> Vector2F {
169 self.anchor.scroll_position(snapshot)
170 }
171
172 fn set_scroll_position(
173 &mut self,
174 scroll_position: Vector2F,
175 map: &DisplaySnapshot,
176 local: bool,
177 autoscroll: bool,
178 workspace_id: Option<i64>,
179 cx: &mut ViewContext<Editor>,
180 ) {
181 let (new_anchor, top_row) = if scroll_position.y() <= 0. {
182 (
183 ScrollAnchor {
184 anchor: Anchor::min(),
185 offset: scroll_position.max(vec2f(0., 0.)),
186 },
187 0,
188 )
189 } else {
190 let scroll_top_buffer_point =
191 DisplayPoint::new(scroll_position.y() as u32, 0).to_point(&map);
192 let top_anchor = map
193 .buffer_snapshot
194 .anchor_at(scroll_top_buffer_point, Bias::Right);
195
196 (
197 ScrollAnchor {
198 anchor: top_anchor,
199 offset: vec2f(
200 scroll_position.x(),
201 scroll_position.y() - top_anchor.to_display_point(&map).row() as f32,
202 ),
203 },
204 scroll_top_buffer_point.row,
205 )
206 };
207
208 self.set_anchor(new_anchor, top_row, local, autoscroll, workspace_id, cx);
209 }
210
211 fn set_anchor(
212 &mut self,
213 anchor: ScrollAnchor,
214 top_row: u32,
215 local: bool,
216 autoscroll: bool,
217 workspace_id: Option<i64>,
218 cx: &mut ViewContext<Editor>,
219 ) {
220 self.anchor = anchor;
221 cx.emit(Event::ScrollPositionChanged { local, autoscroll });
222 self.show_scrollbar(cx);
223 self.autoscroll_request.take();
224 if let Some(workspace_id) = workspace_id {
225 let item_id = cx.view_id();
226
227 cx.background()
228 .spawn(async move {
229 DB.save_scroll_position(
230 item_id,
231 workspace_id,
232 top_row,
233 anchor.offset.x(),
234 anchor.offset.y(),
235 )
236 .await
237 .log_err()
238 })
239 .detach()
240 }
241 cx.notify();
242 }
243
244 pub fn show_scrollbar(&mut self, cx: &mut ViewContext<Editor>) {
245 if !self.show_scrollbars {
246 self.show_scrollbars = true;
247 cx.notify();
248 }
249
250 if cx.default_global::<ScrollbarAutoHide>().0 {
251 self.hide_scrollbar_task = Some(cx.spawn(|editor, mut cx| async move {
252 cx.background().timer(SCROLLBAR_SHOW_INTERVAL).await;
253 editor
254 .update(&mut cx, |editor, cx| {
255 editor.scroll_manager.show_scrollbars = false;
256 cx.notify();
257 })
258 .log_err();
259 }));
260 } else {
261 self.hide_scrollbar_task = None;
262 }
263 }
264
265 pub fn scrollbars_visible(&self) -> bool {
266 self.show_scrollbars
267 }
268
269 pub fn has_autoscroll_request(&self) -> bool {
270 self.autoscroll_request.is_some()
271 }
272
273 pub fn clamp_scroll_left(&mut self, max: f32) -> bool {
274 if max < self.anchor.offset.x() {
275 self.anchor.offset.set_x(max);
276 true
277 } else {
278 false
279 }
280 }
281}
282
283impl Editor {
284 pub fn vertical_scroll_margin(&mut self) -> usize {
285 self.scroll_manager.vertical_scroll_margin as usize
286 }
287
288 pub fn set_vertical_scroll_margin(&mut self, margin_rows: usize, cx: &mut ViewContext<Self>) {
289 self.scroll_manager.vertical_scroll_margin = margin_rows as f32;
290 cx.notify();
291 }
292
293 pub fn visible_line_count(&self) -> Option<f32> {
294 self.scroll_manager.visible_line_count
295 }
296
297 pub(crate) fn set_visible_line_count(&mut self, lines: f32, cx: &mut ViewContext<Self>) {
298 let opened_first_time = self.scroll_manager.visible_line_count.is_none();
299 self.scroll_manager.visible_line_count = Some(lines);
300 if opened_first_time {
301 cx.spawn(|editor, mut cx| async move {
302 editor
303 .update(&mut cx, |editor, cx| {
304 editor.refresh_inlays(InlayRefreshReason::NewLinesShown, cx)
305 })
306 .ok()
307 })
308 .detach()
309 }
310 }
311
312 pub fn set_scroll_position(&mut self, scroll_position: Vector2F, cx: &mut ViewContext<Self>) {
313 self.set_scroll_position_internal(scroll_position, true, false, cx);
314 }
315
316 pub(crate) fn set_scroll_position_internal(
317 &mut self,
318 scroll_position: Vector2F,
319 local: bool,
320 autoscroll: bool,
321 cx: &mut ViewContext<Self>,
322 ) {
323 let map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
324
325 hide_hover(self, cx);
326 let workspace_id = self.workspace.as_ref().map(|workspace| workspace.1);
327 self.scroll_manager.set_scroll_position(
328 scroll_position,
329 &map,
330 local,
331 autoscroll,
332 workspace_id,
333 cx,
334 );
335
336 if !self.is_singleton(cx) {
337 self.refresh_inlays(InlayRefreshReason::NewLinesShown, cx);
338 }
339 }
340
341 pub fn scroll_position(&self, cx: &mut ViewContext<Self>) -> Vector2F {
342 let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
343 self.scroll_manager.anchor.scroll_position(&display_map)
344 }
345
346 pub fn set_scroll_anchor(&mut self, scroll_anchor: ScrollAnchor, cx: &mut ViewContext<Self>) {
347 hide_hover(self, cx);
348 let workspace_id = self.workspace.as_ref().map(|workspace| workspace.1);
349 let top_row = scroll_anchor
350 .anchor
351 .to_point(&self.buffer().read(cx).snapshot(cx))
352 .row;
353 self.scroll_manager
354 .set_anchor(scroll_anchor, top_row, true, false, workspace_id, cx);
355 }
356
357 pub(crate) fn set_scroll_anchor_remote(
358 &mut self,
359 scroll_anchor: ScrollAnchor,
360 cx: &mut ViewContext<Self>,
361 ) {
362 hide_hover(self, cx);
363 let workspace_id = self.workspace.as_ref().map(|workspace| workspace.1);
364 let top_row = scroll_anchor
365 .anchor
366 .to_point(&self.buffer().read(cx).snapshot(cx))
367 .row;
368 self.scroll_manager
369 .set_anchor(scroll_anchor, top_row, false, false, workspace_id, cx);
370 }
371
372 pub fn scroll_screen(&mut self, amount: &ScrollAmount, cx: &mut ViewContext<Self>) {
373 if matches!(self.mode, EditorMode::SingleLine) {
374 cx.propagate_action();
375 return;
376 }
377
378 if self.take_rename(true, cx).is_some() {
379 return;
380 }
381
382 if amount.move_context_menu_selection(self, cx) {
383 return;
384 }
385
386 let cur_position = self.scroll_position(cx);
387 let new_pos = cur_position + vec2f(0., amount.lines(self));
388 self.set_scroll_position(new_pos, cx);
389 }
390
391 /// Returns an ordering. The newest selection is:
392 /// Ordering::Equal => on screen
393 /// Ordering::Less => above the screen
394 /// Ordering::Greater => below the screen
395 pub fn newest_selection_on_screen(&self, cx: &mut AppContext) -> Ordering {
396 let snapshot = self.display_map.update(cx, |map, cx| map.snapshot(cx));
397 let newest_head = self
398 .selections
399 .newest_anchor()
400 .head()
401 .to_display_point(&snapshot);
402 let screen_top = self
403 .scroll_manager
404 .anchor
405 .anchor
406 .to_display_point(&snapshot);
407
408 if screen_top > newest_head {
409 return Ordering::Less;
410 }
411
412 if let Some(visible_lines) = self.visible_line_count() {
413 if newest_head.row() < screen_top.row() + visible_lines as u32 {
414 return Ordering::Equal;
415 }
416 }
417
418 Ordering::Greater
419 }
420
421 pub fn read_scroll_position_from_db(
422 &mut self,
423 item_id: usize,
424 workspace_id: WorkspaceId,
425 cx: &mut ViewContext<Editor>,
426 ) {
427 let scroll_position = DB.get_scroll_position(item_id, workspace_id);
428 if let Ok(Some((top_row, x, y))) = scroll_position {
429 let top_anchor = self
430 .buffer()
431 .read(cx)
432 .snapshot(cx)
433 .anchor_at(Point::new(top_row as u32, 0), Bias::Left);
434 let scroll_anchor = ScrollAnchor {
435 offset: Vector2F::new(x, y),
436 anchor: top_anchor,
437 };
438 self.set_scroll_anchor(scroll_anchor, cx);
439 }
440 }
441}