cursor_position.rs

  1use editor::{Editor, MultiBufferSnapshot};
  2use gpui::{App, Entity, FocusHandle, Focusable, Styled, Subscription, Task, WeakEntity};
  3use settings::Settings;
  4use std::{fmt::Write, num::NonZeroU32, time::Duration};
  5use text::{Point, Selection};
  6use ui::{
  7    Button, ButtonCommon, Clickable, Context, FluentBuilder, IntoElement, LabelSize, ParentElement,
  8    Render, Tooltip, Window, div,
  9};
 10use util::paths::FILE_ROW_COLUMN_DELIMITER;
 11use workspace::{StatusBarSettings, StatusItemView, Workspace, item::ItemHandle};
 12
 13#[derive(Copy, Clone, Debug, Default, PartialOrd, PartialEq)]
 14pub(crate) struct SelectionStats {
 15    pub lines: usize,
 16    pub characters: usize,
 17    pub selections: usize,
 18}
 19
 20pub struct CursorPosition {
 21    position: Option<UserCaretPosition>,
 22    selected_count: SelectionStats,
 23    context: Option<FocusHandle>,
 24    workspace: WeakEntity<Workspace>,
 25    update_position: Task<()>,
 26    _observe_active_editor: Option<Subscription>,
 27}
 28
 29/// A position in the editor, where user's caret is located at.
 30/// Lines are never zero as there is always at least one line in the editor.
 31/// Characters may start with zero as the caret may be at the beginning of a line, but all editors start counting characters from 1,
 32/// where "1" will mean "before the first character".
 33#[derive(Copy, Clone, Debug, PartialEq, Eq)]
 34pub struct UserCaretPosition {
 35    pub line: NonZeroU32,
 36    pub character: NonZeroU32,
 37}
 38
 39impl UserCaretPosition {
 40    pub(crate) fn at_selection_end(
 41        selection: &Selection<Point>,
 42        snapshot: &MultiBufferSnapshot,
 43    ) -> Self {
 44        let selection_end = selection.head();
 45        let (line, character) = if let Some((buffer_snapshot, point, _)) =
 46            snapshot.point_to_buffer_point(selection_end)
 47        {
 48            let line_start = Point::new(point.row, 0);
 49
 50            let chars_to_last_position = buffer_snapshot
 51                .text_summary_for_range::<text::TextSummary, _>(line_start..point)
 52                .chars as u32;
 53            (line_start.row, chars_to_last_position)
 54        } else {
 55            let line_start = Point::new(selection_end.row, 0);
 56
 57            let chars_to_last_position = snapshot
 58                .text_summary_for_range::<text::TextSummary, _>(line_start..selection_end)
 59                .chars as u32;
 60            (selection_end.row, chars_to_last_position)
 61        };
 62
 63        Self {
 64            line: NonZeroU32::new(line + 1).expect("added 1"),
 65            character: NonZeroU32::new(character + 1).expect("added 1"),
 66        }
 67    }
 68}
 69
 70impl CursorPosition {
 71    pub fn new(workspace: &Workspace) -> Self {
 72        Self {
 73            position: None,
 74            context: None,
 75            selected_count: Default::default(),
 76            workspace: workspace.weak_handle(),
 77            update_position: Task::ready(()),
 78            _observe_active_editor: None,
 79        }
 80    }
 81
 82    fn update_position(
 83        &mut self,
 84        editor: Entity<Editor>,
 85        debounce: Option<Duration>,
 86        window: &mut Window,
 87        cx: &mut Context<Self>,
 88    ) {
 89        let editor = editor.downgrade();
 90        self.update_position = cx.spawn_in(window, async move |cursor_position, cx| {
 91            let is_singleton = editor
 92                .update(cx, |editor, cx| editor.buffer().read(cx).is_singleton())
 93                .ok()
 94                .unwrap_or(true);
 95
 96            if !is_singleton && let Some(debounce) = debounce {
 97                cx.background_executor().timer(debounce).await;
 98            }
 99
100            editor
101                .update(cx, |editor, cx| {
102                    cursor_position.update(cx, |cursor_position, cx| {
103                        cursor_position.selected_count = SelectionStats::default();
104                        cursor_position.selected_count.selections = editor.selections.count();
105                        match editor.mode() {
106                            editor::EditorMode::AutoHeight { .. }
107                            | editor::EditorMode::SingleLine
108                            | editor::EditorMode::Minimap { .. } => {
109                                cursor_position.position = None;
110                                cursor_position.context = None;
111                            }
112                            editor::EditorMode::Full { .. } => {
113                                let mut last_selection = None::<Selection<Point>>;
114                                let snapshot = editor.buffer().read(cx).snapshot(cx);
115                                if snapshot.excerpts().count() > 0 {
116                                    for selection in
117                                        editor.selections.all_adjusted_with_snapshot(&snapshot)
118                                    {
119                                        let selection_summary = snapshot
120                                            .text_summary_for_range::<text::TextSummary, _>(
121                                                selection.start..selection.end,
122                                            );
123                                        cursor_position.selected_count.characters +=
124                                            selection_summary.chars;
125                                        if selection.end != selection.start {
126                                            cursor_position.selected_count.lines +=
127                                                (selection.end.row - selection.start.row) as usize;
128                                            if selection.end.column != 0 {
129                                                cursor_position.selected_count.lines += 1;
130                                            }
131                                        }
132                                        if last_selection.as_ref().is_none_or(|last_selection| {
133                                            selection.id > last_selection.id
134                                        }) {
135                                            last_selection = Some(selection);
136                                        }
137                                    }
138                                }
139                                cursor_position.position = last_selection
140                                    .map(|s| UserCaretPosition::at_selection_end(&s, &snapshot));
141                                cursor_position.context = Some(editor.focus_handle(cx));
142                            }
143                        }
144
145                        cx.notify();
146                    })
147                })
148                .ok()
149                .transpose()
150                .ok()
151                .flatten();
152        });
153    }
154
155    fn write_position(&self, text: &mut String, cx: &App) {
156        if self.selected_count
157            <= (SelectionStats {
158                selections: 1,
159                ..Default::default()
160            })
161        {
162            // Do not write out anything if we have just one empty selection.
163            return;
164        }
165        let SelectionStats {
166            lines,
167            characters,
168            selections,
169        } = self.selected_count;
170        let format = LineIndicatorFormat::get(None, cx);
171        let is_short_format = format == &LineIndicatorFormat::Short;
172        let lines = (lines > 1).then_some((lines, "line"));
173        let selections = (selections > 1).then_some((selections, "selection"));
174        let characters = (characters > 0).then_some((characters, "character"));
175        if (None, None, None) == (characters, selections, lines) {
176            // Nothing to display.
177            return;
178        }
179        write!(text, " (").unwrap();
180        let mut wrote_once = false;
181        for (count, name) in [selections, lines, characters].into_iter().flatten() {
182            if wrote_once {
183                write!(text, ", ").unwrap();
184            }
185            let name = if is_short_format { &name[..1] } else { name };
186            let plural_suffix = if count > 1 && !is_short_format {
187                "s"
188            } else {
189                ""
190            };
191            write!(text, "{count} {name}{plural_suffix}").unwrap();
192            wrote_once = true;
193        }
194        text.push(')');
195    }
196
197    #[cfg(test)]
198    pub(crate) fn selection_stats(&self) -> &SelectionStats {
199        &self.selected_count
200    }
201
202    #[cfg(test)]
203    pub(crate) fn position(&self) -> Option<UserCaretPosition> {
204        self.position
205    }
206}
207
208impl Render for CursorPosition {
209    fn render(&mut self, _window: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
210        if !StatusBarSettings::get_global(cx).cursor_position_button {
211            return div().hidden();
212        }
213
214        div().when_some(self.position, |el, position| {
215            let mut text = format!(
216                "{}{FILE_ROW_COLUMN_DELIMITER}{}",
217                position.line, position.character,
218            );
219            self.write_position(&mut text, cx);
220
221            let context = self.context.clone();
222
223            el.child(
224                Button::new("go-to-line-column", text)
225                    .label_size(LabelSize::Small)
226                    .on_click(cx.listener(|this, _, window, cx| {
227                        if let Some(workspace) = this.workspace.upgrade() {
228                            workspace.update(cx, |workspace, cx| {
229                                if let Some(editor) = workspace
230                                    .active_item(cx)
231                                    .and_then(|item| item.act_as::<Editor>(cx))
232                                    && let Some((_, buffer, _)) = editor.read(cx).active_excerpt(cx)
233                                {
234                                    workspace.toggle_modal(window, cx, |window, cx| {
235                                        crate::GoToLine::new(editor, buffer, window, cx)
236                                    })
237                                }
238                            });
239                        }
240                    }))
241                    .tooltip(move |_window, cx| match context.as_ref() {
242                        Some(context) => Tooltip::for_action_in(
243                            "Go to Line/Column",
244                            &editor::actions::ToggleGoToLine,
245                            context,
246                            cx,
247                        ),
248                        None => Tooltip::for_action(
249                            "Go to Line/Column",
250                            &editor::actions::ToggleGoToLine,
251                            cx,
252                        ),
253                    }),
254            )
255        })
256    }
257}
258
259const UPDATE_DEBOUNCE: Duration = Duration::from_millis(50);
260
261impl StatusItemView for CursorPosition {
262    fn set_active_pane_item(
263        &mut self,
264        active_pane_item: Option<&dyn ItemHandle>,
265        window: &mut Window,
266        cx: &mut Context<Self>,
267    ) {
268        if let Some(editor) = active_pane_item.and_then(|item| item.act_as::<Editor>(cx)) {
269            self._observe_active_editor =
270                Some(
271                    cx.observe_in(&editor, window, |cursor_position, editor, window, cx| {
272                        Self::update_position(
273                            cursor_position,
274                            editor,
275                            Some(UPDATE_DEBOUNCE),
276                            window,
277                            cx,
278                        )
279                    }),
280                );
281            self.update_position(editor, None, window, cx);
282        } else {
283            self.position = None;
284            self._observe_active_editor = None;
285        }
286
287        cx.notify();
288    }
289}
290
291#[derive(Clone, Copy, PartialEq, Eq)]
292pub enum LineIndicatorFormat {
293    Short,
294    Long,
295}
296
297impl From<settings::LineIndicatorFormat> for LineIndicatorFormat {
298    fn from(format: settings::LineIndicatorFormat) -> Self {
299        match format {
300            settings::LineIndicatorFormat::Short => LineIndicatorFormat::Short,
301            settings::LineIndicatorFormat::Long => LineIndicatorFormat::Long,
302        }
303    }
304}
305
306impl Settings for LineIndicatorFormat {
307    fn from_settings(content: &settings::SettingsContent) -> Self {
308        content.line_indicator_format.unwrap().into()
309    }
310}