cursor_position.rs

  1use editor::{Editor, MultiBufferSnapshot};
  2use gpui::{App, Entity, FocusHandle, Focusable, 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 editor.selections.all_adjusted(cx) {
117                                        let selection_summary = snapshot
118                                            .text_summary_for_range::<text::TextSummary, _>(
119                                                selection.start..selection.end,
120                                            );
121                                        cursor_position.selected_count.characters +=
122                                            selection_summary.chars;
123                                        if selection.end != selection.start {
124                                            cursor_position.selected_count.lines +=
125                                                (selection.end.row - selection.start.row) as usize;
126                                            if selection.end.column != 0 {
127                                                cursor_position.selected_count.lines += 1;
128                                            }
129                                        }
130                                        if last_selection.as_ref().is_none_or(|last_selection| {
131                                            selection.id > last_selection.id
132                                        }) {
133                                            last_selection = Some(selection);
134                                        }
135                                    }
136                                }
137                                cursor_position.position = last_selection
138                                    .map(|s| UserCaretPosition::at_selection_end(&s, &snapshot));
139                                cursor_position.context = Some(editor.focus_handle(cx));
140                            }
141                        }
142
143                        cx.notify();
144                    })
145                })
146                .ok()
147                .transpose()
148                .ok()
149                .flatten();
150        });
151    }
152
153    fn write_position(&self, text: &mut String, cx: &App) {
154        if self.selected_count
155            <= (SelectionStats {
156                selections: 1,
157                ..Default::default()
158            })
159        {
160            // Do not write out anything if we have just one empty selection.
161            return;
162        }
163        let SelectionStats {
164            lines,
165            characters,
166            selections,
167        } = self.selected_count;
168        let format = LineIndicatorFormat::get(None, cx);
169        let is_short_format = format == &LineIndicatorFormat::Short;
170        let lines = (lines > 1).then_some((lines, "line"));
171        let selections = (selections > 1).then_some((selections, "selection"));
172        let characters = (characters > 0).then_some((characters, "character"));
173        if (None, None, None) == (characters, selections, lines) {
174            // Nothing to display.
175            return;
176        }
177        write!(text, " (").unwrap();
178        let mut wrote_once = false;
179        for (count, name) in [selections, lines, characters].into_iter().flatten() {
180            if wrote_once {
181                write!(text, ", ").unwrap();
182            }
183            let name = if is_short_format { &name[..1] } else { name };
184            let plural_suffix = if count > 1 && !is_short_format {
185                "s"
186            } else {
187                ""
188            };
189            write!(text, "{count} {name}{plural_suffix}").unwrap();
190            wrote_once = true;
191        }
192        text.push(')');
193    }
194
195    #[cfg(test)]
196    pub(crate) fn selection_stats(&self) -> &SelectionStats {
197        &self.selected_count
198    }
199
200    #[cfg(test)]
201    pub(crate) fn position(&self) -> Option<UserCaretPosition> {
202        self.position
203    }
204}
205
206impl Render for CursorPosition {
207    fn render(&mut self, _window: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
208        if !StatusBarSettings::get_global(cx).cursor_position_button {
209            return div();
210        }
211
212        div().when_some(self.position, |el, position| {
213            let mut text = format!(
214                "{}{FILE_ROW_COLUMN_DELIMITER}{}",
215                position.line, position.character,
216            );
217            self.write_position(&mut text, cx);
218
219            let context = self.context.clone();
220
221            el.child(
222                Button::new("go-to-line-column", text)
223                    .label_size(LabelSize::Small)
224                    .on_click(cx.listener(|this, _, window, cx| {
225                        if let Some(workspace) = this.workspace.upgrade() {
226                            workspace.update(cx, |workspace, cx| {
227                                if let Some(editor) = workspace
228                                    .active_item(cx)
229                                    .and_then(|item| item.act_as::<Editor>(cx))
230                                    && let Some((_, buffer, _)) = editor.read(cx).active_excerpt(cx)
231                                {
232                                    workspace.toggle_modal(window, cx, |window, cx| {
233                                        crate::GoToLine::new(editor, buffer, window, cx)
234                                    })
235                                }
236                            });
237                        }
238                    }))
239                    .tooltip(move |window, cx| match context.as_ref() {
240                        Some(context) => Tooltip::for_action_in(
241                            "Go to Line/Column",
242                            &editor::actions::ToggleGoToLine,
243                            context,
244                            window,
245                            cx,
246                        ),
247                        None => Tooltip::for_action(
248                            "Go to Line/Column",
249                            &editor::actions::ToggleGoToLine,
250                            window,
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}