syntax_tree_view.rs

  1use editor::{scroll::autoscroll::Autoscroll, Anchor, Editor, ExcerptId};
  2use gpui::{
  3    actions, div, overlay, red, uniform_list, AnyElement, AppContext, CursorStyle, Div,
  4    EventEmitter, FocusHandle, FocusableView, Hsla, InteractiveElement, IntoElement, Model,
  5    MouseButton, ParentElement, Render, Styled, TextStyle, UniformListState, View, ViewContext,
  6    VisualContext, WeakView, WindowContext,
  7};
  8use language::{Buffer, OwnedSyntaxLayerInfo, SyntaxLayerInfo};
  9use settings::Settings;
 10use std::{mem, ops::Range};
 11use theme::{ActiveTheme, ThemeSettings};
 12use tree_sitter::{Node, TreeCursor};
 13use ui::{h_stack, Label};
 14use workspace::{
 15    item::{Item, ItemHandle},
 16    ui::v_stack,
 17    ToolbarItemEvent, ToolbarItemLocation, ToolbarItemView, Workspace,
 18};
 19
 20actions!(debug, [OpenSyntaxTreeView]);
 21
 22pub fn init(cx: &mut AppContext) {
 23    cx.observe_new_views(|workspace: &mut Workspace, _| {
 24        workspace.register_action(|workspace, _: &OpenSyntaxTreeView, cx| {
 25            let active_item = workspace.active_item(cx);
 26            let workspace_handle = workspace.weak_handle();
 27            let syntax_tree_view =
 28                cx.build_view(|cx| SyntaxTreeView::new(workspace_handle, active_item, cx));
 29            workspace.add_item(Box::new(syntax_tree_view), cx);
 30        });
 31    })
 32    .detach();
 33}
 34
 35pub struct SyntaxTreeView {
 36    workspace_handle: WeakView<Workspace>,
 37    editor: Option<EditorState>,
 38    mouse_y: Option<f32>,
 39    line_height: Option<f32>,
 40    list_state: UniformListState,
 41    selected_descendant_ix: Option<usize>,
 42    hovered_descendant_ix: Option<usize>,
 43    focus_handle: FocusHandle,
 44}
 45
 46pub struct SyntaxTreeToolbarItemView {
 47    tree_view: Option<View<SyntaxTreeView>>,
 48    subscription: Option<gpui::Subscription>,
 49    menu_open: bool,
 50}
 51
 52struct EditorState {
 53    editor: View<Editor>,
 54    active_buffer: Option<BufferState>,
 55    _subscription: gpui::Subscription,
 56}
 57
 58#[derive(Clone)]
 59struct BufferState {
 60    buffer: Model<Buffer>,
 61    excerpt_id: ExcerptId,
 62    active_layer: Option<OwnedSyntaxLayerInfo>,
 63}
 64
 65impl SyntaxTreeView {
 66    pub fn new(
 67        workspace_handle: WeakView<Workspace>,
 68        active_item: Option<Box<dyn ItemHandle>>,
 69        cx: &mut ViewContext<Self>,
 70    ) -> Self {
 71        let mut this = Self {
 72            workspace_handle: workspace_handle.clone(),
 73            list_state: UniformListState::default(),
 74            editor: None,
 75            mouse_y: None,
 76            line_height: None,
 77            hovered_descendant_ix: None,
 78            selected_descendant_ix: None,
 79            focus_handle: cx.focus_handle(),
 80        };
 81
 82        this.workspace_updated(active_item, cx);
 83        cx.observe(
 84            &workspace_handle.upgrade().unwrap(),
 85            |this, workspace, cx| {
 86                this.workspace_updated(workspace.read(cx).active_item(cx), cx);
 87            },
 88        )
 89        .detach();
 90
 91        this
 92    }
 93
 94    fn workspace_updated(
 95        &mut self,
 96        active_item: Option<Box<dyn ItemHandle>>,
 97        cx: &mut ViewContext<Self>,
 98    ) {
 99        if let Some(item) = active_item {
100            if item.item_id() != cx.entity_id() {
101                if let Some(editor) = item.act_as::<Editor>(cx) {
102                    self.set_editor(editor, cx);
103                }
104            }
105        }
106    }
107
108    fn set_editor(&mut self, editor: View<Editor>, cx: &mut ViewContext<Self>) {
109        if let Some(state) = &self.editor {
110            if state.editor == editor {
111                return;
112            }
113            editor.update(cx, |editor, cx| {
114                editor.clear_background_highlights::<Self>(cx)
115            });
116        }
117
118        let subscription = cx.subscribe(&editor, |this, _, event, cx| {
119            let did_reparse = match event {
120                editor::EditorEvent::Reparsed => true,
121                editor::EditorEvent::SelectionsChanged { .. } => false,
122                _ => return,
123            };
124            this.editor_updated(did_reparse, cx);
125        });
126
127        self.editor = Some(EditorState {
128            editor,
129            _subscription: subscription,
130            active_buffer: None,
131        });
132        self.editor_updated(true, cx);
133    }
134
135    fn editor_updated(&mut self, did_reparse: bool, cx: &mut ViewContext<Self>) -> Option<()> {
136        // Find which excerpt the cursor is in, and the position within that excerpted buffer.
137        let editor_state = self.editor.as_mut()?;
138        let editor = &editor_state.editor.read(cx);
139        let selection_range = editor.selections.last::<usize>(cx).range();
140        let multibuffer = editor.buffer().read(cx);
141        let (buffer, range, excerpt_id) = multibuffer
142            .range_to_buffer_ranges(selection_range, cx)
143            .pop()?;
144
145        // If the cursor has moved into a different excerpt, retrieve a new syntax layer
146        // from that buffer.
147        let buffer_state = editor_state
148            .active_buffer
149            .get_or_insert_with(|| BufferState {
150                buffer: buffer.clone(),
151                excerpt_id,
152                active_layer: None,
153            });
154        let mut prev_layer = None;
155        if did_reparse {
156            prev_layer = buffer_state.active_layer.take();
157        }
158        if buffer_state.buffer != buffer || buffer_state.excerpt_id != buffer_state.excerpt_id {
159            buffer_state.buffer = buffer.clone();
160            buffer_state.excerpt_id = excerpt_id;
161            buffer_state.active_layer = None;
162        }
163
164        let layer = match &mut buffer_state.active_layer {
165            Some(layer) => layer,
166            None => {
167                let snapshot = buffer.read(cx).snapshot();
168                let layer = if let Some(prev_layer) = prev_layer {
169                    let prev_range = prev_layer.node().byte_range();
170                    snapshot
171                        .syntax_layers()
172                        .filter(|layer| layer.language == &prev_layer.language)
173                        .min_by_key(|layer| {
174                            let range = layer.node().byte_range();
175                            ((range.start as i64) - (prev_range.start as i64)).abs()
176                                + ((range.end as i64) - (prev_range.end as i64)).abs()
177                        })?
178                } else {
179                    snapshot.syntax_layers().next()?
180                };
181                buffer_state.active_layer.insert(layer.to_owned())
182            }
183        };
184
185        // Within the active layer, find the syntax node under the cursor,
186        // and scroll to it.
187        let mut cursor = layer.node().walk();
188        while cursor.goto_first_child_for_byte(range.start).is_some() {
189            if !range.is_empty() && cursor.node().end_byte() == range.start {
190                cursor.goto_next_sibling();
191            }
192        }
193
194        // Ascend to the smallest ancestor that contains the range.
195        loop {
196            let node_range = cursor.node().byte_range();
197            if node_range.start <= range.start && node_range.end >= range.end {
198                break;
199            }
200            if !cursor.goto_parent() {
201                break;
202            }
203        }
204
205        let descendant_ix = cursor.descendant_index();
206        self.selected_descendant_ix = Some(descendant_ix);
207        self.list_state.scroll_to(ScrollTarget::Show(descendant_ix));
208
209        cx.notify();
210        Some(())
211    }
212
213    fn handle_click(&mut self, y: f32, cx: &mut ViewContext<SyntaxTreeView>) -> Option<()> {
214        let line_height = self.line_height?;
215        let ix = ((self.list_state.scroll_top() + y) / line_height) as usize;
216
217        self.update_editor_with_range_for_descendant_ix(ix, cx, |editor, mut range, cx| {
218            // Put the cursor at the beginning of the node.
219            mem::swap(&mut range.start, &mut range.end);
220
221            editor.change_selections(Some(Autoscroll::newest()), cx, |selections| {
222                selections.select_ranges(vec![range]);
223            });
224        });
225        Some(())
226    }
227
228    fn hover_state_changed(&mut self, cx: &mut ViewContext<SyntaxTreeView>) {
229        if let Some((y, line_height)) = self.mouse_y.zip(self.line_height) {
230            let ix = ((self.list_state.scroll_top() + y) / line_height) as usize;
231            if self.hovered_descendant_ix != Some(ix) {
232                self.hovered_descendant_ix = Some(ix);
233                self.update_editor_with_range_for_descendant_ix(ix, cx, |editor, range, cx| {
234                    editor.clear_background_highlights::<Self>(cx);
235                    editor.highlight_background::<Self>(
236                        vec![range],
237                        |theme| theme.editor_document_highlight_write_background,
238                        cx,
239                    );
240                });
241                cx.notify();
242            }
243        }
244    }
245
246    fn update_editor_with_range_for_descendant_ix(
247        &self,
248        descendant_ix: usize,
249        cx: &mut ViewContext<Self>,
250        mut f: impl FnMut(&mut Editor, Range<Anchor>, &mut ViewContext<Editor>),
251    ) -> Option<()> {
252        let editor_state = self.editor.as_ref()?;
253        let buffer_state = editor_state.active_buffer.as_ref()?;
254        let layer = buffer_state.active_layer.as_ref()?;
255
256        // Find the node.
257        let mut cursor = layer.node().walk();
258        cursor.goto_descendant(descendant_ix);
259        let node = cursor.node();
260        let range = node.byte_range();
261
262        // Build a text anchor range.
263        let buffer = buffer_state.buffer.read(cx);
264        let range = buffer.anchor_before(range.start)..buffer.anchor_after(range.end);
265
266        // Build a multibuffer anchor range.
267        let multibuffer = editor_state.editor.read(cx).buffer();
268        let multibuffer = multibuffer.read(cx).snapshot(cx);
269        let excerpt_id = buffer_state.excerpt_id;
270        let range = multibuffer.anchor_in_excerpt(excerpt_id, range.start)
271            ..multibuffer.anchor_in_excerpt(excerpt_id, range.end);
272
273        // Update the editor with the anchor range.
274        editor_state.editor.update(cx, |editor, cx| {
275            f(editor, range, cx);
276        });
277        Some(())
278    }
279
280    fn render_node(
281        cursor: &TreeCursor,
282        depth: u32,
283        selected: bool,
284        hovered: bool,
285        list_hovered: bool,
286        style: &TextStyle,
287        editor_theme: &theme::Editor,
288        cx: &AppContext,
289    ) -> Div {
290        let node = cursor.node();
291        let mut range_style = style.clone();
292        let em_width = style.em_width(cx.text_system());
293        let gutter_padding = (em_width * editor_theme.gutter_padding_factor).round();
294
295        range_style.color = editor_theme.line_number;
296
297        let mut anonymous_node_style = style.clone();
298        let string_color = editor_theme
299            .syntax
300            .highlights
301            .iter()
302            .find_map(|(name, style)| (name == "string").then(|| style.color)?);
303        let property_color = editor_theme
304            .syntax
305            .highlights
306            .iter()
307            .find_map(|(name, style)| (name == "property").then(|| style.color)?);
308        if let Some(color) = string_color {
309            anonymous_node_style.color = color;
310        }
311
312        let mut row = h_stack();
313        if let Some(field_name) = cursor.field_name() {
314            let mut field_style = style.clone();
315            if let Some(color) = property_color {
316                field_style.color = color;
317            }
318
319            row = row.children([Label::new(field_name), Label::new(": ")]);
320        }
321
322        return row
323            .child(
324                if node.is_named() {
325                    Label::new(node.kind())
326                } else {
327                    Label::new(format!("\"{}\"", node.kind()))
328                }, // todo!()
329                   // .margin(em_width),
330            )
331            .child(Label::new(format_node_range(node)))
332            .text_bg(if selected {
333                editor_theme.selection.selection
334            } else if hovered && list_hovered {
335                editor_theme.active_line_background
336            } else {
337                Hsla::default()
338            })
339            // todo!()
340            // .padding(gutter_padding + depth as f32 * 18.0)
341            .border_1()
342            .border_color(red());
343    }
344}
345
346impl Render for SyntaxTreeView {
347    // todo!()
348    // fn ui_name() -> &'static str {
349    //     "SyntaxTreeView"
350    // }
351
352    type Element = Div;
353
354    fn render(&mut self, cx: &mut gpui::ViewContext<'_, Self>) -> Div {
355        let settings = ThemeSettings::get_global(cx);
356        let font = settings.buffer_font;
357        let font_size = settings.buffer_font_size(cx);
358
359        let editor_theme = settings.active_theme;
360        let style = TextStyle {
361            color: editor_theme.text_color,
362            font_family_name,
363            font_family_id,
364            font_id,
365            font_size,
366            font_properties: Default::default(),
367            underline: Default::default(),
368            font_family: todo!(),
369            font_features: todo!(),
370            line_height: todo!(),
371            font_weight: todo!(),
372            font_style: todo!(),
373            background_color: todo!(),
374            white_space: todo!(),
375        };
376
377        let line_height = cx.text_system().line_height(font_size);
378        if Some(line_height) != self.line_height {
379            self.line_height = Some(line_height);
380            self.hover_state_changed(cx);
381        }
382
383        if let Some(layer) = self
384            .editor
385            .as_ref()
386            .and_then(|editor| editor.active_buffer.as_ref())
387            .and_then(|buffer| buffer.active_layer.as_ref())
388        {
389            let layer = layer.clone();
390            let theme = editor_theme.clone();
391
392            let list_hovered = state.hovered();
393            uniform_list(
394                self.list_state.clone(),
395                layer.node().descendant_count(),
396                cx,
397                move |this, range, items, cx| {
398                    let mut cursor = layer.node().walk();
399                    let mut descendant_ix = range.start as usize;
400                    cursor.goto_descendant(descendant_ix);
401                    let mut depth = cursor.depth();
402                    let mut visited_children = false;
403                    while descendant_ix < range.end {
404                        if visited_children {
405                            if cursor.goto_next_sibling() {
406                                visited_children = false;
407                            } else if cursor.goto_parent() {
408                                depth -= 1;
409                            } else {
410                                break;
411                            }
412                        } else {
413                            items.push(Self::render_node(
414                                &cursor,
415                                depth,
416                                Some(descendant_ix) == this.selected_descendant_ix,
417                                Some(descendant_ix) == this.hovered_descendant_ix,
418                                list_hovered,
419                                &style,
420                                &theme,
421                                cx,
422                            ));
423                            descendant_ix += 1;
424                            if cursor.goto_first_child() {
425                                depth += 1;
426                            } else {
427                                visited_children = true;
428                            }
429                        }
430                    }
431                },
432            )
433            .on_move(move |event, this, cx| {
434                let y = event.position.y() - event.region.origin_y();
435                this.mouse_y = Some(y);
436                this.hover_state_changed(cx);
437            })
438            .on_mouse_down(MouseButton::Left, move |event, cx| {
439                let y = event.position.y() - event.region.origin_y();
440                self.handle_click(y, cx);
441            });
442        }
443
444        div()
445    }
446}
447
448impl EventEmitter<()> for SyntaxTreeView {}
449
450impl FocusableView for SyntaxTreeView {
451    fn focus_handle(&self, _: &AppContext) -> gpui::FocusHandle {
452        self.focus_handle.clone()
453    }
454}
455
456impl Item for SyntaxTreeView {
457    type Event = ();
458
459    fn to_item_events(_: &Self::Event, _: impl FnMut(workspace::item::ItemEvent)) {}
460
461    fn tab_content(&self, _: Option<usize>, _: bool, _: &WindowContext<'_>) -> AnyElement {
462        Label::new("Syntax Tree").into_any_element()
463    }
464
465    fn clone_on_split(
466        &self,
467        _: workspace::WorkspaceId,
468        cx: &mut ViewContext<Self>,
469    ) -> Option<View<Self>>
470    where
471        Self: Sized,
472    {
473        Some(cx.build_view(|cx| {
474            let mut clone = Self::new(self.workspace_handle.clone(), None, cx);
475            if let Some(editor) = &self.editor {
476                clone.set_editor(editor.editor.clone(), cx)
477            }
478            clone
479        }))
480    }
481}
482
483impl SyntaxTreeToolbarItemView {
484    pub fn new() -> Self {
485        Self {
486            menu_open: false,
487            tree_view: None,
488            subscription: None,
489        }
490    }
491
492    fn render_menu(&mut self, cx: &mut ViewContext<'_, Self>) -> Option<Div> {
493        let theme = cx.theme().clone();
494        let tree_view = self.tree_view.as_ref()?;
495        let tree_view = tree_view.read(cx);
496
497        let editor_state = tree_view.editor.as_ref()?;
498        let buffer_state = editor_state.active_buffer.as_ref()?;
499        let active_layer = buffer_state.active_layer.clone()?;
500        let active_buffer = buffer_state.buffer.read(cx).snapshot();
501
502        Some(
503            v_stack()
504                .child(Self::render_header(&active_layer, cx))
505                .children(self.menu_open.then(|| {
506                    overlay().child(
507                        v_stack()
508                            .children(active_buffer.syntax_layers().enumerate().map(
509                                |(ix, layer)| Self::render_menu_item(&active_layer, layer, ix, cx),
510                            ))
511                            .on_mouse_down_out(|e, cx| {
512                                if e.button == MouseButton::Left {
513                                    self.menu_open = false;
514                                    cx.notify()
515                                }
516                            }),
517                    )
518                })),
519        )
520    }
521
522    fn toggle_menu(&mut self, cx: &mut ViewContext<Self>) {
523        self.menu_open = !self.menu_open;
524        cx.notify();
525    }
526
527    fn select_layer(&mut self, layer_ix: usize, cx: &mut ViewContext<Self>) -> Option<()> {
528        let tree_view = self.tree_view.as_ref()?;
529        tree_view.update(cx, |view, cx| {
530            let editor_state = view.editor.as_mut()?;
531            let buffer_state = editor_state.active_buffer.as_mut()?;
532            let snapshot = buffer_state.buffer.read(cx).snapshot();
533            let layer = snapshot.syntax_layers().nth(layer_ix)?;
534            buffer_state.active_layer = Some(layer.to_owned());
535            view.selected_descendant_ix = None;
536            self.menu_open = false;
537            cx.notify();
538            Some(())
539        })
540    }
541
542    fn render_header(active_layer: &OwnedSyntaxLayerInfo, cx: &mut ViewContext<Self>) -> Div {
543        let view = cx.view().clone();
544        h_stack()
545            .child(Label::new(active_layer.language.name()))
546            .child(Label::new(format_node_range(active_layer.node())))
547            .on_mouse_down(MouseButton::Left, move |_, cx| {
548                view.update(cx, |view, cx| view.toggle_menu(cx));
549            })
550            .cursor(CursorStyle::PointingHand)
551            .border_1()
552            .border_color(red())
553    }
554
555    fn render_menu_item(
556        active_layer: &OwnedSyntaxLayerInfo,
557        layer: SyntaxLayerInfo,
558        layer_ix: usize,
559        cx: &mut ViewContext<Self>,
560    ) -> Div {
561        // todo!() styling
562        let _is_selected = layer.node() == active_layer.node();
563        let view = cx.view().clone();
564        h_stack()
565            .child(Label::new(layer.language.name().to_string()))
566            .child(Label::new(format_node_range(layer.node())))
567            .cursor(CursorStyle::PointingHand)
568            .on_mouse_down(MouseButton::Left, move |_, cx| {
569                view.update(cx, |view, cx| {
570                    view.select_layer(layer_ix, cx);
571                })
572            })
573            .border_1()
574            .border_color(red())
575    }
576}
577
578fn format_node_range(node: Node) -> String {
579    let start = node.start_position();
580    let end = node.end_position();
581    format!(
582        "[{}:{} - {}:{}]",
583        start.row + 1,
584        start.column + 1,
585        end.row + 1,
586        end.column + 1,
587    )
588}
589
590impl Render for SyntaxTreeToolbarItemView {
591    type Element = Div;
592
593    // todo!()
594    // fn ui_name() -> &'static str {
595    //     "SyntaxTreeToolbarItemView"
596    // }
597
598    fn render(&mut self, cx: &mut ViewContext<'_, Self>) -> Div {
599        self.render_menu(cx).unwrap_or_else(|| div())
600    }
601}
602
603impl EventEmitter<ToolbarItemEvent> for SyntaxTreeToolbarItemView {}
604
605impl ToolbarItemView for SyntaxTreeToolbarItemView {
606    fn set_active_pane_item(
607        &mut self,
608        active_pane_item: Option<&dyn ItemHandle>,
609        cx: &mut ViewContext<Self>,
610    ) -> ToolbarItemLocation {
611        self.menu_open = false;
612        if let Some(item) = active_pane_item {
613            if let Some(view) = item.downcast::<SyntaxTreeView>() {
614                self.tree_view = Some(view.clone());
615                self.subscription = Some(cx.observe(&view, |_, _, cx| cx.notify()));
616                return ToolbarItemLocation::PrimaryLeft;
617            }
618        }
619        self.tree_view = None;
620        self.subscription = None;
621        ToolbarItemLocation::Hidden
622    }
623}