element.rs

   1use super::{
   2    display_map::{BlockContext, ToDisplayPoint},
   3    Anchor, DisplayPoint, Editor, EditorMode, EditorSnapshot, Select, SelectPhase, SoftWrap,
   4    ToPoint, MAX_LINE_LEN,
   5};
   6use crate::{
   7    display_map::{BlockStyle, DisplaySnapshot, FoldStatus, TransformBlock},
   8    git::{diff_hunk_to_display, DisplayDiffHunk},
   9    hover_popover::{
  10        HideHover, HoverAt, HOVER_POPOVER_GAP, MIN_POPOVER_CHARACTER_WIDTH, MIN_POPOVER_LINE_HEIGHT,
  11    },
  12    link_go_to_definition::{
  13        GoToFetchedDefinition, GoToFetchedTypeDefinition, UpdateGoToDefinitionLink,
  14    },
  15    mouse_context_menu::DeployMouseContextMenu,
  16    scroll::actions::Scroll,
  17    EditorStyle, GutterHover, UnfoldAt,
  18};
  19use clock::ReplicaId;
  20use collections::{BTreeMap, HashMap};
  21use git::diff::DiffHunkStatus;
  22use gpui::{
  23    color::Color,
  24    elements::*,
  25    fonts::{HighlightStyle, Underline},
  26    geometry::{
  27        rect::RectF,
  28        vector::{vec2f, Vector2F},
  29        PathBuilder,
  30    },
  31    json::{self, ToJson},
  32    platform::{CursorStyle, Modifiers, MouseButton, MouseButtonEvent, MouseMovedEvent},
  33    text_layout::{self, Line, RunStyle, TextLayoutCache},
  34    AppContext, Axis, Border, CursorRegion, Element, ElementBox, MouseRegion, Quad, SceneBuilder,
  35    SizeConstraint, ViewContext, WeakViewHandle,
  36};
  37use itertools::Itertools;
  38use json::json;
  39use language::{Bias, CursorShape, DiagnosticSeverity, OffsetUtf16, Selection};
  40use project::ProjectPath;
  41use settings::{GitGutter, Settings};
  42use smallvec::SmallVec;
  43use std::{
  44    cmp::{self, Ordering},
  45    fmt::Write,
  46    iter,
  47    ops::{DerefMut, Range},
  48    sync::Arc,
  49};
  50use workspace::item::Item;
  51
  52enum FoldMarkers {}
  53
  54struct SelectionLayout {
  55    head: DisplayPoint,
  56    cursor_shape: CursorShape,
  57    range: Range<DisplayPoint>,
  58}
  59
  60impl SelectionLayout {
  61    fn new<T: ToPoint + ToDisplayPoint + Clone>(
  62        selection: Selection<T>,
  63        line_mode: bool,
  64        cursor_shape: CursorShape,
  65        map: &DisplaySnapshot,
  66    ) -> Self {
  67        if line_mode {
  68            let selection = selection.map(|p| p.to_point(&map.buffer_snapshot));
  69            let point_range = map.expand_to_line(selection.range());
  70            Self {
  71                head: selection.head().to_display_point(map),
  72                cursor_shape,
  73                range: point_range.start.to_display_point(map)
  74                    ..point_range.end.to_display_point(map),
  75            }
  76        } else {
  77            let selection = selection.map(|p| p.to_display_point(map));
  78            Self {
  79                head: selection.head(),
  80                cursor_shape,
  81                range: selection.range(),
  82            }
  83        }
  84    }
  85}
  86
  87#[derive(Clone)]
  88pub struct EditorElement {
  89    view: WeakViewHandle<Editor>,
  90    style: Arc<EditorStyle>,
  91}
  92
  93impl EditorElement {
  94    pub fn new(view: WeakViewHandle<Editor>, style: EditorStyle) -> Self {
  95        Self {
  96            view,
  97            style: Arc::new(style),
  98        }
  99    }
 100
 101    fn view<'a>(&self, cx: &'a AppContext) -> &'a Editor {
 102        self.view.upgrade(cx).unwrap().read(cx)
 103    }
 104
 105    fn update_view<F, T>(&self, cx: &mut AppContext, f: F) -> T
 106    where
 107        F: FnOnce(&mut Editor, &mut ViewContext<Editor>) -> T,
 108    {
 109        self.view.upgrade(cx).unwrap().update(cx, f)
 110    }
 111
 112    fn snapshot(&self, cx: &mut AppContext) -> EditorSnapshot {
 113        self.update_view(cx, |view, cx| view.snapshot(cx))
 114    }
 115
 116    fn attach_mouse_handlers(
 117        view: &WeakViewHandle<Editor>,
 118        position_map: &Arc<PositionMap>,
 119        has_popovers: bool,
 120        visible_bounds: RectF,
 121        text_bounds: RectF,
 122        gutter_bounds: RectF,
 123        bounds: RectF,
 124        cx: &mut PaintContext,
 125    ) {
 126        enum EditorElementMouseHandlers {}
 127        scene.push_mouse_region(
 128            MouseRegion::new::<EditorElementMouseHandlers>(view.id(), view.id(), visible_bounds)
 129                .on_down(MouseButton::Left, {
 130                    let position_map = position_map.clone();
 131                    move |e, cx| {
 132                        if !Self::mouse_down(
 133                            e.platform_event,
 134                            position_map.as_ref(),
 135                            text_bounds,
 136                            gutter_bounds,
 137                            cx,
 138                        ) {
 139                            cx.propagate_event();
 140                        }
 141                    }
 142                })
 143                .on_down(MouseButton::Right, {
 144                    let position_map = position_map.clone();
 145                    move |e, cx| {
 146                        if !Self::mouse_right_down(
 147                            e.position,
 148                            position_map.as_ref(),
 149                            text_bounds,
 150                            cx,
 151                        ) {
 152                            cx.propagate_event();
 153                        }
 154                    }
 155                })
 156                .on_up(MouseButton::Left, {
 157                    let view = view.clone();
 158                    let position_map = position_map.clone();
 159                    move |e, cx| {
 160                        if !Self::mouse_up(
 161                            view.clone(),
 162                            e.position,
 163                            e.cmd,
 164                            e.shift,
 165                            position_map.as_ref(),
 166                            text_bounds,
 167                            cx,
 168                        ) {
 169                            cx.propagate_event()
 170                        }
 171                    }
 172                })
 173                .on_drag(MouseButton::Left, {
 174                    let view = view.clone();
 175                    let position_map = position_map.clone();
 176                    move |e, cx| {
 177                        if !Self::mouse_dragged(
 178                            view.clone(),
 179                            e.platform_event,
 180                            position_map.as_ref(),
 181                            text_bounds,
 182                            cx,
 183                        ) {
 184                            cx.propagate_event()
 185                        }
 186                    }
 187                })
 188                .on_move({
 189                    let position_map = position_map.clone();
 190                    move |e, cx| {
 191                        if !Self::mouse_moved(e.platform_event, &position_map, text_bounds, cx) {
 192                            cx.propagate_event()
 193                        }
 194                    }
 195                })
 196                .on_move_out(move |_, cx| {
 197                    if has_popovers {
 198                        cx.dispatch_action(HideHover);
 199                    }
 200                })
 201                .on_scroll({
 202                    let position_map = position_map.clone();
 203                    move |e, cx| {
 204                        if !Self::scroll(
 205                            e.position,
 206                            *e.delta.raw(),
 207                            e.delta.precise(),
 208                            &position_map,
 209                            bounds,
 210                            cx,
 211                        ) {
 212                            cx.propagate_event()
 213                        }
 214                    }
 215                }),
 216        );
 217
 218        enum GutterHandlers {}
 219        scene.push_mouse_region(
 220            MouseRegion::new::<GutterHandlers>(view.id(), view.id() + 1, gutter_bounds).on_hover(
 221                |hover, cx| {
 222                    cx.dispatch_action(GutterHover {
 223                        hovered: hover.started,
 224                    })
 225                },
 226            ),
 227        )
 228    }
 229
 230    fn mouse_down(
 231        MouseButtonEvent {
 232            position,
 233            modifiers:
 234                Modifiers {
 235                    shift,
 236                    ctrl,
 237                    alt,
 238                    cmd,
 239                    ..
 240                },
 241            mut click_count,
 242            ..
 243        }: MouseButtonEvent,
 244        position_map: &PositionMap,
 245        text_bounds: RectF,
 246        gutter_bounds: RectF,
 247        cx: &mut EventContext,
 248    ) -> bool {
 249        if gutter_bounds.contains_point(position) {
 250            click_count = 3; // Simulate triple-click when clicking the gutter to select lines
 251        } else if !text_bounds.contains_point(position) {
 252            return false;
 253        }
 254
 255        let (position, target_position) = position_map.point_for_position(text_bounds, position);
 256
 257        if shift && alt {
 258            cx.dispatch_action(Select(SelectPhase::BeginColumnar {
 259                position,
 260                goal_column: target_position.column(),
 261            }));
 262        } else if shift && !ctrl && !alt && !cmd {
 263            cx.dispatch_action(Select(SelectPhase::Extend {
 264                position,
 265                click_count,
 266            }));
 267        } else {
 268            cx.dispatch_action(Select(SelectPhase::Begin {
 269                position,
 270                add: alt,
 271                click_count,
 272            }));
 273        }
 274
 275        true
 276    }
 277
 278    fn mouse_right_down(
 279        position: Vector2F,
 280        position_map: &PositionMap,
 281        text_bounds: RectF,
 282        cx: &mut EventContext,
 283    ) -> bool {
 284        if !text_bounds.contains_point(position) {
 285            return false;
 286        }
 287
 288        let (point, _) = position_map.point_for_position(text_bounds, position);
 289
 290        cx.dispatch_action(DeployMouseContextMenu { position, point });
 291        true
 292    }
 293
 294    fn mouse_up(
 295        view: WeakViewHandle<Editor>,
 296        position: Vector2F,
 297        cmd: bool,
 298        shift: bool,
 299        position_map: &PositionMap,
 300        text_bounds: RectF,
 301        cx: &mut EventContext,
 302    ) -> bool {
 303        let view = view.upgrade(cx.app).unwrap().read(cx.app);
 304        let end_selection = view.has_pending_selection();
 305        let pending_nonempty_selections = view.has_pending_nonempty_selection();
 306
 307        if end_selection {
 308            cx.dispatch_action(Select(SelectPhase::End));
 309        }
 310
 311        if !pending_nonempty_selections && cmd && text_bounds.contains_point(position) {
 312            let (point, target_point) = position_map.point_for_position(text_bounds, position);
 313
 314            if point == target_point {
 315                if shift {
 316                    cx.dispatch_action(GoToFetchedTypeDefinition { point });
 317                } else {
 318                    cx.dispatch_action(GoToFetchedDefinition { point });
 319                }
 320
 321                return true;
 322            }
 323        }
 324
 325        end_selection
 326    }
 327
 328    fn mouse_dragged(
 329        view: WeakViewHandle<Editor>,
 330        MouseMovedEvent {
 331            modifiers: Modifiers { cmd, shift, .. },
 332            position,
 333            ..
 334        }: MouseMovedEvent,
 335        position_map: &PositionMap,
 336        text_bounds: RectF,
 337        cx: &mut EventContext,
 338    ) -> bool {
 339        // This will be handled more correctly once https://github.com/zed-industries/zed/issues/1218 is completed
 340        // Don't trigger hover popover if mouse is hovering over context menu
 341        let point = if text_bounds.contains_point(position) {
 342            let (point, target_point) = position_map.point_for_position(text_bounds, position);
 343            if point == target_point {
 344                Some(point)
 345            } else {
 346                None
 347            }
 348        } else {
 349            None
 350        };
 351
 352        cx.dispatch_action(UpdateGoToDefinitionLink {
 353            point,
 354            cmd_held: cmd,
 355            shift_held: shift,
 356        });
 357
 358        let view = view.upgrade(cx.app).unwrap().read(cx.app);
 359        if view.has_pending_selection() {
 360            let mut scroll_delta = Vector2F::zero();
 361
 362            let vertical_margin = position_map.line_height.min(text_bounds.height() / 3.0);
 363            let top = text_bounds.origin_y() + vertical_margin;
 364            let bottom = text_bounds.lower_left().y() - vertical_margin;
 365            if position.y() < top {
 366                scroll_delta.set_y(-scale_vertical_mouse_autoscroll_delta(top - position.y()))
 367            }
 368            if position.y() > bottom {
 369                scroll_delta.set_y(scale_vertical_mouse_autoscroll_delta(position.y() - bottom))
 370            }
 371
 372            let horizontal_margin = position_map.line_height.min(text_bounds.width() / 3.0);
 373            let left = text_bounds.origin_x() + horizontal_margin;
 374            let right = text_bounds.upper_right().x() - horizontal_margin;
 375            if position.x() < left {
 376                scroll_delta.set_x(-scale_horizontal_mouse_autoscroll_delta(
 377                    left - position.x(),
 378                ))
 379            }
 380            if position.x() > right {
 381                scroll_delta.set_x(scale_horizontal_mouse_autoscroll_delta(
 382                    position.x() - right,
 383                ))
 384            }
 385
 386            let (position, target_position) =
 387                position_map.point_for_position(text_bounds, position);
 388
 389            cx.dispatch_action(Select(SelectPhase::Update {
 390                position,
 391                goal_column: target_position.column(),
 392                scroll_position: (position_map.snapshot.scroll_position() + scroll_delta)
 393                    .clamp(Vector2F::zero(), position_map.scroll_max),
 394            }));
 395
 396            cx.dispatch_action(HoverAt { point });
 397            true
 398        } else {
 399            cx.dispatch_action(HoverAt { point });
 400            false
 401        }
 402    }
 403
 404    fn mouse_moved(
 405        MouseMovedEvent {
 406            modifiers: Modifiers { shift, cmd, .. },
 407            position,
 408            ..
 409        }: MouseMovedEvent,
 410        position_map: &PositionMap,
 411        text_bounds: RectF,
 412        cx: &mut ViewContext<Editor>,
 413    ) -> bool {
 414        // This will be handled more correctly once https://github.com/zed-industries/zed/issues/1218 is completed
 415        // Don't trigger hover popover if mouse is hovering over context menu
 416        let point = position_to_display_point(position, text_bounds, position_map);
 417
 418        cx.dispatch_action(UpdateGoToDefinitionLink {
 419            point,
 420            cmd_held: cmd,
 421            shift_held: shift,
 422        });
 423
 424        cx.dispatch_action(HoverAt { point });
 425
 426        true
 427    }
 428
 429    fn scroll(
 430        position: Vector2F,
 431        mut delta: Vector2F,
 432        precise: bool,
 433        position_map: &PositionMap,
 434        bounds: RectF,
 435        cx: &mut ViewContext<Editor>,
 436    ) -> bool {
 437        if !bounds.contains_point(position) {
 438            return false;
 439        }
 440
 441        let line_height = position_map.line_height;
 442        let max_glyph_width = position_map.em_width;
 443
 444        let axis = if precise {
 445            //Trackpad
 446            position_map.snapshot.ongoing_scroll.filter(&mut delta)
 447        } else {
 448            //Not trackpad
 449            delta *= vec2f(max_glyph_width, line_height);
 450            None //Resets ongoing scroll
 451        };
 452
 453        let scroll_position = position_map.snapshot.scroll_position();
 454        let x = (scroll_position.x() * max_glyph_width - delta.x()) / max_glyph_width;
 455        let y = (scroll_position.y() * line_height - delta.y()) / line_height;
 456        let scroll_position = vec2f(x, y).clamp(Vector2F::zero(), position_map.scroll_max);
 457
 458        cx.dispatch_action(Scroll {
 459            scroll_position,
 460            axis,
 461        });
 462
 463        true
 464    }
 465
 466    fn paint_background(
 467        &self,
 468        scene: &mut SceneBuilder,
 469        gutter_bounds: RectF,
 470        text_bounds: RectF,
 471        layout: &LayoutState,
 472        cx: &mut ViewContext<Editor>,
 473    ) {
 474        let bounds = gutter_bounds.union_rect(text_bounds);
 475        let scroll_top =
 476            layout.position_map.snapshot.scroll_position().y() * layout.position_map.line_height;
 477        scene.push_quad(Quad {
 478            bounds: gutter_bounds,
 479            background: Some(self.style.gutter_background),
 480            border: Border::new(0., Color::transparent_black()),
 481            corner_radius: 0.,
 482        });
 483        c.push_quad(Quad {
 484            bounds: text_bounds,
 485            background: Some(self.style.background),
 486            border: Border::new(0., Color::transparent_black()),
 487            corner_radius: 0.,
 488        });
 489
 490        if let EditorMode::Full = layout.mode {
 491            let mut active_rows = layout.active_rows.iter().peekable();
 492            while let Some((start_row, contains_non_empty_selection)) = active_rows.next() {
 493                let mut end_row = *start_row;
 494                while active_rows.peek().map_or(false, |r| {
 495                    *r.0 == end_row + 1 && r.1 == contains_non_empty_selection
 496                }) {
 497                    active_rows.next().unwrap();
 498                    end_row += 1;
 499                }
 500
 501                if !contains_non_empty_selection {
 502                    let origin = vec2f(
 503                        bounds.origin_x(),
 504                        bounds.origin_y() + (layout.position_map.line_height * *start_row as f32)
 505                            - scroll_top,
 506                    );
 507                    let size = vec2f(
 508                        bounds.width(),
 509                        layout.position_map.line_height * (end_row - start_row + 1) as f32,
 510                    );
 511                    scene.push_quad(Quad {
 512                        bounds: RectF::new(origin, size),
 513                        background: Some(self.style.active_line_background),
 514                        border: Border::default(),
 515                        corner_radius: 0.,
 516                    });
 517                }
 518            }
 519
 520            if let Some(highlighted_rows) = &layout.highlighted_rows {
 521                let origin = vec2f(
 522                    bounds.origin_x(),
 523                    bounds.origin_y()
 524                        + (layout.position_map.line_height * highlighted_rows.start as f32)
 525                        - scroll_top,
 526                );
 527                let size = vec2f(
 528                    bounds.width(),
 529                    layout.position_map.line_height * highlighted_rows.len() as f32,
 530                );
 531                scene.push_quad(Quad {
 532                    bounds: RectF::new(origin, size),
 533                    background: Some(self.style.highlighted_line_background),
 534                    border: Border::default(),
 535                    corner_radius: 0.,
 536                });
 537            }
 538        }
 539    }
 540
 541    fn paint_gutter(
 542        &mut self,
 543        scene: &mut SceneBuilder,
 544        bounds: RectF,
 545        visible_bounds: RectF,
 546        layout: &mut LayoutState,
 547        editor: &mut Editor,
 548        cx: &mut PaintContext,
 549    ) {
 550        let line_height = layout.position_map.line_height;
 551
 552        let scroll_position = layout.position_map.snapshot.scroll_position();
 553        let scroll_top = scroll_position.y() * line_height;
 554
 555        let show_gutter = matches!(
 556            &cx.global::<Settings>()
 557                .git_overrides
 558                .git_gutter
 559                .unwrap_or_default(),
 560            GitGutter::TrackedFiles
 561        );
 562
 563        if show_gutter {
 564            Self::paint_diff_hunks(bounds, layout, cx);
 565        }
 566
 567        for (ix, line) in layout.line_number_layouts.iter().enumerate() {
 568            if let Some(line) = line {
 569                let line_origin = bounds.origin()
 570                    + vec2f(
 571                        bounds.width() - line.width() - layout.gutter_padding,
 572                        ix as f32 * line_height - (scroll_top % line_height),
 573                    );
 574
 575                line.paint(scene, line_origin, visible_bounds, line_height, cx);
 576            }
 577        }
 578
 579        for (ix, fold_indicator) in layout.fold_indicators.iter_mut().enumerate() {
 580            if let Some(indicator) = fold_indicator.as_mut() {
 581                let position = vec2f(
 582                    bounds.width() - layout.gutter_padding,
 583                    ix as f32 * line_height - (scroll_top % line_height),
 584                );
 585                let centering_offset = vec2f(
 586                    (layout.gutter_padding + layout.gutter_margin - indicator.size().x()) / 2.,
 587                    (line_height - indicator.size().y()) / 2.,
 588                );
 589
 590                let indicator_origin = bounds.origin() + position + centering_offset;
 591
 592                indicator.paint(scene, indicator_origin, visible_bounds, editor, cx);
 593            }
 594        }
 595
 596        if let Some((row, indicator)) = layout.code_actions_indicator.as_mut() {
 597            let mut x = 0.;
 598            let mut y = *row as f32 * line_height - scroll_top;
 599            x += ((layout.gutter_padding + layout.gutter_margin) - indicator.size().x()) / 2.;
 600            y += (line_height - indicator.size().y()) / 2.;
 601            indicator.paint(
 602                scene,
 603                bounds.origin() + vec2f(x, y),
 604                visible_bounds,
 605                editor,
 606                cx,
 607            );
 608        }
 609    }
 610
 611    fn paint_diff_hunks(bounds: RectF, layout: &mut LayoutState, cx: &mut PaintContext) {
 612        let diff_style = &cx.global::<Settings>().theme.editor.diff.clone();
 613        let line_height = layout.position_map.line_height;
 614
 615        let scroll_position = layout.position_map.snapshot.scroll_position();
 616        let scroll_top = scroll_position.y() * line_height;
 617
 618        for hunk in &layout.display_hunks {
 619            let (display_row_range, status) = match hunk {
 620                //TODO: This rendering is entirely a horrible hack
 621                &DisplayDiffHunk::Folded { display_row: row } => {
 622                    let start_y = row as f32 * line_height - scroll_top;
 623                    let end_y = start_y + line_height;
 624
 625                    let width = diff_style.removed_width_em * line_height;
 626                    let highlight_origin = bounds.origin() + vec2f(-width, start_y);
 627                    let highlight_size = vec2f(width * 2., end_y - start_y);
 628                    let highlight_bounds = RectF::new(highlight_origin, highlight_size);
 629
 630                    scene.push_quad(Quad {
 631                        bounds: highlight_bounds,
 632                        background: Some(diff_style.modified),
 633                        border: Border::new(0., Color::transparent_black()),
 634                        corner_radius: 1. * line_height,
 635                    });
 636
 637                    continue;
 638                }
 639
 640                DisplayDiffHunk::Unfolded {
 641                    display_row_range,
 642                    status,
 643                } => (display_row_range, status),
 644            };
 645
 646            let color = match status {
 647                DiffHunkStatus::Added => diff_style.inserted,
 648                DiffHunkStatus::Modified => diff_style.modified,
 649
 650                //TODO: This rendering is entirely a horrible hack
 651                DiffHunkStatus::Removed => {
 652                    let row = *display_row_range.start();
 653
 654                    let offset = line_height / 2.;
 655                    let start_y = row as f32 * line_height - offset - scroll_top;
 656                    let end_y = start_y + line_height;
 657
 658                    let width = diff_style.removed_width_em * line_height;
 659                    let highlight_origin = bounds.origin() + vec2f(-width, start_y);
 660                    let highlight_size = vec2f(width * 2., end_y - start_y);
 661                    let highlight_bounds = RectF::new(highlight_origin, highlight_size);
 662
 663                    scene.push_quad(Quad {
 664                        bounds: highlight_bounds,
 665                        background: Some(diff_style.deleted),
 666                        border: Border::new(0., Color::transparent_black()),
 667                        corner_radius: 1. * line_height,
 668                    });
 669
 670                    continue;
 671                }
 672            };
 673
 674            let start_row = *display_row_range.start();
 675            let end_row = *display_row_range.end();
 676
 677            let start_y = start_row as f32 * line_height - scroll_top;
 678            let end_y = end_row as f32 * line_height - scroll_top + line_height;
 679
 680            let width = diff_style.width_em * line_height;
 681            let highlight_origin = bounds.origin() + vec2f(-width, start_y);
 682            let highlight_size = vec2f(width * 2., end_y - start_y);
 683            let highlight_bounds = RectF::new(highlight_origin, highlight_size);
 684
 685            scene.push_quad(Quad {
 686                bounds: highlight_bounds,
 687                background: Some(color),
 688                border: Border::new(0., Color::transparent_black()),
 689                corner_radius: diff_style.corner_radius * line_height,
 690            });
 691        }
 692    }
 693
 694    fn paint_text(
 695        &mut self,
 696        scene: &mut SceneBuilder,
 697        bounds: RectF,
 698        visible_bounds: RectF,
 699        layout: &mut LayoutState,
 700        editor: &mut Editor,
 701        cx: &mut PaintContext,
 702    ) {
 703        let view = self.view(cx.app);
 704        let style = &self.style;
 705        let local_replica_id = view.replica_id(cx);
 706        let scroll_position = layout.position_map.snapshot.scroll_position();
 707        let start_row = layout.visible_display_row_range.start;
 708        let scroll_top = scroll_position.y() * layout.position_map.line_height;
 709        let max_glyph_width = layout.position_map.em_width;
 710        let scroll_left = scroll_position.x() * max_glyph_width;
 711        let content_origin = bounds.origin() + vec2f(layout.gutter_margin, 0.);
 712        let line_end_overshoot = 0.15 * layout.position_map.line_height;
 713
 714        scene.push_layer(Some(bounds));
 715
 716        scene.push_cursor_region(CursorRegion {
 717            bounds,
 718            style: if !view.link_go_to_definition_state.definitions.is_empty() {
 719                CursorStyle::PointingHand
 720            } else {
 721                CursorStyle::IBeam
 722            },
 723        });
 724
 725        let fold_corner_radius =
 726            self.style.folds.ellipses.corner_radius_factor * layout.position_map.line_height;
 727        for (id, range, color) in layout.fold_ranges.iter() {
 728            self.paint_highlighted_range(
 729                scene,
 730                range.clone(),
 731                *color,
 732                fold_corner_radius,
 733                fold_corner_radius * 2.,
 734                layout,
 735                content_origin,
 736                scroll_top,
 737                scroll_left,
 738                bounds,
 739                cx,
 740            );
 741
 742            for bound in range_to_bounds(
 743                &range,
 744                content_origin,
 745                scroll_left,
 746                scroll_top,
 747                &layout.visible_display_row_range,
 748                line_end_overshoot,
 749                &layout.position_map,
 750            ) {
 751                scene.push_cursor_region(CursorRegion {
 752                    bounds: bound,
 753                    style: CursorStyle::PointingHand,
 754                });
 755
 756                let display_row = range.start.row();
 757
 758                let buffer_row = DisplayPoint::new(display_row, 0)
 759                    .to_point(&layout.position_map.snapshot.display_snapshot)
 760                    .row;
 761
 762                scene.push_mouse_region(
 763                    MouseRegion::new::<FoldMarkers>(self.view.id(), *id as usize, bound)
 764                        .on_click(MouseButton::Left, move |_, cx| {
 765                            cx.dispatch_action(UnfoldAt { buffer_row })
 766                        })
 767                        .with_notify_on_hover(true)
 768                        .with_notify_on_click(true),
 769                )
 770            }
 771        }
 772
 773        for (range, color) in &layout.highlighted_ranges {
 774            self.paint_highlighted_range(
 775                scene,
 776                range.clone(),
 777                *color,
 778                0.,
 779                line_end_overshoot,
 780                layout,
 781                content_origin,
 782                scroll_top,
 783                scroll_left,
 784                bounds,
 785                cx,
 786            );
 787        }
 788
 789        let mut cursors = SmallVec::<[Cursor; 32]>::new();
 790        let corner_radius = 0.15 * layout.position_map.line_height;
 791
 792        for (replica_id, selections) in &layout.selections {
 793            let selection_style = style.replica_selection_style(*replica_id);
 794
 795            for selection in selections {
 796                self.paint_highlighted_range(
 797                    scene,
 798                    selection.range.clone(),
 799                    selection_style.selection,
 800                    corner_radius,
 801                    corner_radius * 2.,
 802                    layout,
 803                    content_origin,
 804                    scroll_top,
 805                    scroll_left,
 806                    bounds,
 807                    cx,
 808                );
 809
 810                if view.show_local_cursors(cx) || *replica_id != local_replica_id {
 811                    let cursor_position = selection.head;
 812                    if layout
 813                        .visible_display_row_range
 814                        .contains(&cursor_position.row())
 815                    {
 816                        let cursor_row_layout = &layout.position_map.line_layouts
 817                            [(cursor_position.row() - start_row) as usize];
 818                        let cursor_column = cursor_position.column() as usize;
 819
 820                        let cursor_character_x = cursor_row_layout.x_for_index(cursor_column);
 821                        let mut block_width =
 822                            cursor_row_layout.x_for_index(cursor_column + 1) - cursor_character_x;
 823                        if block_width == 0.0 {
 824                            block_width = layout.position_map.em_width;
 825                        }
 826                        let block_text = if let CursorShape::Block = selection.cursor_shape {
 827                            layout
 828                                .position_map
 829                                .snapshot
 830                                .chars_at(cursor_position)
 831                                .next()
 832                                .and_then(|(character, _)| {
 833                                    let font_id =
 834                                        cursor_row_layout.font_for_index(cursor_column)?;
 835                                    let text = character.to_string();
 836
 837                                    Some(cx.text_layout_cache.layout_str(
 838                                        &text,
 839                                        cursor_row_layout.font_size(),
 840                                        &[(
 841                                            text.len(),
 842                                            RunStyle {
 843                                                font_id,
 844                                                color: style.background,
 845                                                underline: Default::default(),
 846                                            },
 847                                        )],
 848                                    ))
 849                                })
 850                        } else {
 851                            None
 852                        };
 853
 854                        let x = cursor_character_x - scroll_left;
 855                        let y = cursor_position.row() as f32 * layout.position_map.line_height
 856                            - scroll_top;
 857                        cursors.push(Cursor {
 858                            color: selection_style.cursor,
 859                            block_width,
 860                            origin: vec2f(x, y),
 861                            line_height: layout.position_map.line_height,
 862                            shape: selection.cursor_shape,
 863                            block_text,
 864                        });
 865                    }
 866                }
 867            }
 868        }
 869
 870        if let Some(visible_text_bounds) = bounds.intersection(visible_bounds) {
 871            // Draw glyphs
 872            for (ix, line) in layout.position_map.line_layouts.iter().enumerate() {
 873                let row = start_row + ix as u32;
 874                line.paint(
 875                    scene,
 876                    content_origin
 877                        + vec2f(
 878                            -scroll_left,
 879                            row as f32 * layout.position_map.line_height - scroll_top,
 880                        ),
 881                    visible_text_bounds,
 882                    layout.position_map.line_height,
 883                    cx,
 884                );
 885            }
 886        }
 887
 888        scene.push_layer(Some(bounds));
 889
 890        scene.paint_layer(Some(bounds), |scene| {
 891            for cursor in cursors {
 892                cursor.paint(scene, content_origin, cx);
 893            }
 894        });
 895
 896        if let Some((position, context_menu)) = layout.context_menu.as_mut() {
 897            scene.push_stacking_context(None, None);
 898            let cursor_row_layout =
 899                &layout.position_map.line_layouts[(position.row() - start_row) as usize];
 900            let x = cursor_row_layout.x_for_index(position.column() as usize) - scroll_left;
 901            let y = (position.row() + 1) as f32 * layout.position_map.line_height - scroll_top;
 902            let mut list_origin = content_origin + vec2f(x, y);
 903            let list_width = context_menu.size().x();
 904            let list_height = context_menu.size().y();
 905
 906            // Snap the right edge of the list to the right edge of the window if
 907            // its horizontal bounds overflow.
 908            if list_origin.x() + list_width > cx.window_size.x() {
 909                list_origin.set_x((cx.window_size.x() - list_width).max(0.));
 910            }
 911
 912            if list_origin.y() + list_height > bounds.max_y() {
 913                list_origin.set_y(list_origin.y() - layout.position_map.line_height - list_height);
 914            }
 915
 916            context_menu.paint(
 917                scene,
 918                list_origin,
 919                RectF::from_points(Vector2F::zero(), vec2f(f32::MAX, f32::MAX)), // Let content bleed outside of editor
 920                editor,
 921                cx,
 922            );
 923
 924            scene.pop_stacking_context();
 925        }
 926
 927        if let Some((position, hover_popovers)) = layout.hover_popovers.as_mut() {
 928            scene.push_stacking_context(None, None);
 929
 930            // This is safe because we check on layout whether the required row is available
 931            let hovered_row_layout =
 932                &layout.position_map.line_layouts[(position.row() - start_row) as usize];
 933
 934            // Minimum required size: Take the first popover, and add 1.5 times the minimum popover
 935            // height. This is the size we will use to decide whether to render popovers above or below
 936            // the hovered line.
 937            let first_size = hover_popovers[0].size();
 938            let height_to_reserve = first_size.y()
 939                + 1.5 * MIN_POPOVER_LINE_HEIGHT as f32 * layout.position_map.line_height;
 940
 941            // Compute Hovered Point
 942            let x = hovered_row_layout.x_for_index(position.column() as usize) - scroll_left;
 943            let y = position.row() as f32 * layout.position_map.line_height - scroll_top;
 944            let hovered_point = content_origin + vec2f(x, y);
 945
 946            if hovered_point.y() - height_to_reserve > 0.0 {
 947                // There is enough space above. Render popovers above the hovered point
 948                let mut current_y = hovered_point.y();
 949                for hover_popover in hover_popovers {
 950                    let size = hover_popover.size();
 951                    let mut popover_origin = vec2f(hovered_point.x(), current_y - size.y());
 952
 953                    let x_out_of_bounds = bounds.max_x() - (popover_origin.x() + size.x());
 954                    if x_out_of_bounds < 0.0 {
 955                        popover_origin.set_x(popover_origin.x() + x_out_of_bounds);
 956                    }
 957
 958                    hover_popover.paint(
 959                        scene,
 960                        popover_origin,
 961                        RectF::from_points(Vector2F::zero(), vec2f(f32::MAX, f32::MAX)), // Let content bleed outside of editor
 962                        editor,
 963                        cx,
 964                    );
 965
 966                    current_y = popover_origin.y() - HOVER_POPOVER_GAP;
 967                }
 968            } else {
 969                // There is not enough space above. Render popovers below the hovered point
 970                let mut current_y = hovered_point.y() + layout.position_map.line_height;
 971                for hover_popover in hover_popovers {
 972                    let size = hover_popover.size();
 973                    let mut popover_origin = vec2f(hovered_point.x(), current_y);
 974
 975                    let x_out_of_bounds = bounds.max_x() - (popover_origin.x() + size.x());
 976                    if x_out_of_bounds < 0.0 {
 977                        popover_origin.set_x(popover_origin.x() + x_out_of_bounds);
 978                    }
 979
 980                    hover_popover.paint(
 981                        scene,
 982                        popover_origin,
 983                        RectF::from_points(Vector2F::zero(), vec2f(f32::MAX, f32::MAX)), // Let content bleed outside of editor
 984                        editor,
 985                        cx,
 986                    );
 987
 988                    current_y = popover_origin.y() + size.y() + HOVER_POPOVER_GAP;
 989                }
 990            }
 991
 992            scene.pop_stacking_context();
 993        }
 994
 995        scene.pop_layer();
 996    }
 997
 998    fn paint_scrollbar(
 999        &mut self,
1000        scene: &mut SceneBuilder,
1001        bounds: RectF,
1002        layout: &mut LayoutState,
1003        cx: &mut ViewContext<Editor>,
1004    ) {
1005        enum ScrollbarMouseHandlers {}
1006        if layout.mode != EditorMode::Full {
1007            return;
1008        }
1009
1010        let view = self.view.clone();
1011        let style = &self.style.theme.scrollbar;
1012
1013        let top = bounds.min_y();
1014        let bottom = bounds.max_y();
1015        let right = bounds.max_x();
1016        let left = right - style.width;
1017        let row_range = &layout.scrollbar_row_range;
1018        let max_row = layout.max_row as f32 + (row_range.end - row_range.start);
1019
1020        let mut height = bounds.height();
1021        let mut first_row_y_offset = 0.0;
1022
1023        // Impose a minimum height on the scrollbar thumb
1024        let min_thumb_height =
1025            style.min_height_factor * cx.font_cache.line_height(self.style.text.font_size);
1026        let thumb_height = (row_range.end - row_range.start) * height / max_row;
1027        if thumb_height < min_thumb_height {
1028            first_row_y_offset = (min_thumb_height - thumb_height) / 2.0;
1029            height -= min_thumb_height - thumb_height;
1030        }
1031
1032        let y_for_row = |row: f32| -> f32 { top + first_row_y_offset + row * height / max_row };
1033
1034        let thumb_top = y_for_row(row_range.start) - first_row_y_offset;
1035        let thumb_bottom = y_for_row(row_range.end) + first_row_y_offset;
1036        let track_bounds = RectF::from_points(vec2f(left, top), vec2f(right, bottom));
1037        let thumb_bounds = RectF::from_points(vec2f(left, thumb_top), vec2f(right, thumb_bottom));
1038
1039        if layout.show_scrollbars {
1040            scene.push_quad(Quad {
1041                bounds: track_bounds,
1042                border: style.track.border,
1043                background: style.track.background_color,
1044                ..Default::default()
1045            });
1046            scene.push_quad(Quad {
1047                bounds: thumb_bounds,
1048                border: style.thumb.border,
1049                background: style.thumb.background_color,
1050                corner_radius: style.thumb.corner_radius,
1051            });
1052        }
1053
1054        scene.push_cursor_region(CursorRegion {
1055            bounds: track_bounds,
1056            style: CursorStyle::Arrow,
1057        });
1058        scene.push_mouse_region(
1059            MouseRegion::new::<ScrollbarMouseHandlers>(view.id(), view.id(), track_bounds)
1060                .on_move({
1061                    let view = view.clone();
1062                    move |_, cx| {
1063                        if let Some(view) = view.upgrade(cx.deref_mut()) {
1064                            view.update(cx.deref_mut(), |view, cx| {
1065                                view.scroll_manager.show_scrollbar(cx);
1066                            });
1067                        }
1068                    }
1069                })
1070                .on_down(MouseButton::Left, {
1071                    let view = view.clone();
1072                    let row_range = row_range.clone();
1073                    move |e, cx| {
1074                        let y = e.position.y();
1075                        if let Some(view) = view.upgrade(cx.deref_mut()) {
1076                            view.update(cx.deref_mut(), |view, cx| {
1077                                if y < thumb_top || thumb_bottom < y {
1078                                    let center_row =
1079                                        ((y - top) * max_row as f32 / height).round() as u32;
1080                                    let top_row = center_row.saturating_sub(
1081                                        (row_range.end - row_range.start) as u32 / 2,
1082                                    );
1083                                    let mut position = view.scroll_position(cx);
1084                                    position.set_y(top_row as f32);
1085                                    view.set_scroll_position(position, cx);
1086                                } else {
1087                                    view.scroll_manager.show_scrollbar(cx);
1088                                }
1089                            });
1090                        }
1091                    }
1092                })
1093                .on_drag(MouseButton::Left, {
1094                    let view = view.clone();
1095                    move |e, cx| {
1096                        let y = e.prev_mouse_position.y();
1097                        let new_y = e.position.y();
1098                        if thumb_top < y && y < thumb_bottom {
1099                            if let Some(view) = view.upgrade(cx.deref_mut()) {
1100                                view.update(cx.deref_mut(), |view, cx| {
1101                                    let mut position = view.scroll_position(cx);
1102                                    position.set_y(
1103                                        position.y() + (new_y - y) * (max_row as f32) / height,
1104                                    );
1105                                    if position.y() < 0.0 {
1106                                        position.set_y(0.);
1107                                    }
1108                                    view.set_scroll_position(position, cx);
1109                                });
1110                            }
1111                        }
1112                    }
1113                }),
1114        );
1115    }
1116
1117    #[allow(clippy::too_many_arguments)]
1118    fn paint_highlighted_range(
1119        &self,
1120        scene: &mut SceneBuilder,
1121        range: Range<DisplayPoint>,
1122        color: Color,
1123        corner_radius: f32,
1124        line_end_overshoot: f32,
1125        layout: &LayoutState,
1126        content_origin: Vector2F,
1127        scroll_top: f32,
1128        scroll_left: f32,
1129        bounds: RectF,
1130        cx: &mut ViewContext<Self>,
1131    ) {
1132        let start_row = layout.visible_display_row_range.start;
1133        let end_row = layout.visible_display_row_range.end;
1134        if range.start != range.end {
1135            let row_range = if range.end.column() == 0 {
1136                cmp::max(range.start.row(), start_row)..cmp::min(range.end.row(), end_row)
1137            } else {
1138                cmp::max(range.start.row(), start_row)..cmp::min(range.end.row() + 1, end_row)
1139            };
1140
1141            let highlighted_range = HighlightedRange {
1142                color,
1143                line_height: layout.position_map.line_height,
1144                corner_radius,
1145                start_y: content_origin.y()
1146                    + row_range.start as f32 * layout.position_map.line_height
1147                    - scroll_top,
1148                lines: row_range
1149                    .into_iter()
1150                    .map(|row| {
1151                        let line_layout =
1152                            &layout.position_map.line_layouts[(row - start_row) as usize];
1153                        HighlightedRangeLine {
1154                            start_x: if row == range.start.row() {
1155                                content_origin.x()
1156                                    + line_layout.x_for_index(range.start.column() as usize)
1157                                    - scroll_left
1158                            } else {
1159                                content_origin.x() - scroll_left
1160                            },
1161                            end_x: if row == range.end.row() {
1162                                content_origin.x()
1163                                    + line_layout.x_for_index(range.end.column() as usize)
1164                                    - scroll_left
1165                            } else {
1166                                content_origin.x() + line_layout.width() + line_end_overshoot
1167                                    - scroll_left
1168                            },
1169                        }
1170                    })
1171                    .collect(),
1172            };
1173
1174            highlighted_range.paint(bounds, scene);
1175        }
1176    }
1177
1178    fn paint_blocks(
1179        &mut self,
1180        scene: &mut SceneBuilder,
1181        bounds: RectF,
1182        visible_bounds: RectF,
1183        layout: &mut LayoutState,
1184        editor: &mut Editor,
1185        cx: &mut PaintContext,
1186    ) {
1187        let scroll_position = layout.position_map.snapshot.scroll_position();
1188        let scroll_left = scroll_position.x() * layout.position_map.em_width;
1189        let scroll_top = scroll_position.y() * layout.position_map.line_height;
1190
1191        for block in &mut layout.blocks {
1192            let mut origin = bounds.origin()
1193                + vec2f(
1194                    0.,
1195                    block.row as f32 * layout.position_map.line_height - scroll_top,
1196                );
1197            if !matches!(block.style, BlockStyle::Sticky) {
1198                origin += vec2f(-scroll_left, 0.);
1199            }
1200            block
1201                .element
1202                .paint(scene, origin, visible_bounds, editor, cx);
1203        }
1204    }
1205
1206    fn max_line_number_width(&self, snapshot: &EditorSnapshot, cx: &LayoutContext) -> f32 {
1207        let digit_count = (snapshot.max_buffer_row() as f32).log10().floor() as usize + 1;
1208        let style = &self.style;
1209
1210        cx.text_layout_cache
1211            .layout_str(
1212                "1".repeat(digit_count).as_str(),
1213                style.text.font_size,
1214                &[(
1215                    digit_count,
1216                    RunStyle {
1217                        font_id: style.text.font_id,
1218                        color: Color::black(),
1219                        underline: Default::default(),
1220                    },
1221                )],
1222            )
1223            .width()
1224    }
1225
1226    //Folds contained in a hunk are ignored apart from shrinking visual size
1227    //If a fold contains any hunks then that fold line is marked as modified
1228    fn layout_git_gutters(
1229        &self,
1230        display_rows: Range<u32>,
1231        snapshot: &EditorSnapshot,
1232    ) -> Vec<DisplayDiffHunk> {
1233        let buffer_snapshot = &snapshot.buffer_snapshot;
1234
1235        let buffer_start_row = DisplayPoint::new(display_rows.start, 0)
1236            .to_point(snapshot)
1237            .row;
1238        let buffer_end_row = DisplayPoint::new(display_rows.end, 0)
1239            .to_point(snapshot)
1240            .row;
1241
1242        buffer_snapshot
1243            .git_diff_hunks_in_range(buffer_start_row..buffer_end_row, false)
1244            .map(|hunk| diff_hunk_to_display(hunk, snapshot))
1245            .dedup()
1246            .collect()
1247    }
1248
1249    fn layout_line_numbers(
1250        &self,
1251        rows: Range<u32>,
1252        active_rows: &BTreeMap<u32, bool>,
1253        is_singleton: bool,
1254        snapshot: &EditorSnapshot,
1255        cx: &LayoutContext,
1256    ) -> (
1257        Vec<Option<text_layout::Line>>,
1258        Vec<Option<(FoldStatus, BufferRow, bool)>>,
1259    ) {
1260        let style = &self.style;
1261        let include_line_numbers = snapshot.mode == EditorMode::Full;
1262        let mut line_number_layouts = Vec::with_capacity(rows.len());
1263        let mut fold_statuses = Vec::with_capacity(rows.len());
1264        let mut line_number = String::new();
1265        for (ix, row) in snapshot
1266            .buffer_rows(rows.start)
1267            .take((rows.end - rows.start) as usize)
1268            .enumerate()
1269        {
1270            let display_row = rows.start + ix as u32;
1271            let (active, color) = if active_rows.contains_key(&display_row) {
1272                (true, style.line_number_active)
1273            } else {
1274                (false, style.line_number)
1275            };
1276            if let Some(buffer_row) = row {
1277                if include_line_numbers {
1278                    line_number.clear();
1279                    write!(&mut line_number, "{}", buffer_row + 1).unwrap();
1280                    line_number_layouts.push(Some(cx.text_layout_cache.layout_str(
1281                        &line_number,
1282                        style.text.font_size,
1283                        &[(
1284                            line_number.len(),
1285                            RunStyle {
1286                                font_id: style.text.font_id,
1287                                color,
1288                                underline: Default::default(),
1289                            },
1290                        )],
1291                    )));
1292                    fold_statuses.push(
1293                        is_singleton
1294                            .then(|| {
1295                                snapshot
1296                                    .fold_for_line(buffer_row)
1297                                    .map(|fold_status| (fold_status, buffer_row, active))
1298                            })
1299                            .flatten(),
1300                    )
1301                }
1302            } else {
1303                fold_statuses.push(None);
1304                line_number_layouts.push(None);
1305            }
1306        }
1307
1308        (line_number_layouts, fold_statuses)
1309    }
1310
1311    fn layout_lines(
1312        &mut self,
1313        rows: Range<u32>,
1314        snapshot: &EditorSnapshot,
1315        cx: &LayoutContext,
1316    ) -> Vec<text_layout::Line> {
1317        if rows.start >= rows.end {
1318            return Vec::new();
1319        }
1320
1321        // When the editor is empty and unfocused, then show the placeholder.
1322        if snapshot.is_empty() {
1323            let placeholder_style = self
1324                .style
1325                .placeholder_text
1326                .as_ref()
1327                .unwrap_or(&self.style.text);
1328            let placeholder_text = snapshot.placeholder_text();
1329            let placeholder_lines = placeholder_text
1330                .as_ref()
1331                .map_or("", AsRef::as_ref)
1332                .split('\n')
1333                .skip(rows.start as usize)
1334                .chain(iter::repeat(""))
1335                .take(rows.len());
1336            placeholder_lines
1337                .map(|line| {
1338                    cx.text_layout_cache.layout_str(
1339                        line,
1340                        placeholder_style.font_size,
1341                        &[(
1342                            line.len(),
1343                            RunStyle {
1344                                font_id: placeholder_style.font_id,
1345                                color: placeholder_style.color,
1346                                underline: Default::default(),
1347                            },
1348                        )],
1349                    )
1350                })
1351                .collect()
1352        } else {
1353            let style = &self.style;
1354            let chunks = snapshot
1355                .chunks(rows.clone(), true, Some(style.theme.suggestion))
1356                .map(|chunk| {
1357                    let mut highlight_style = chunk
1358                        .syntax_highlight_id
1359                        .and_then(|id| id.style(&style.syntax));
1360
1361                    if let Some(chunk_highlight) = chunk.highlight_style {
1362                        if let Some(highlight_style) = highlight_style.as_mut() {
1363                            highlight_style.highlight(chunk_highlight);
1364                        } else {
1365                            highlight_style = Some(chunk_highlight);
1366                        }
1367                    }
1368
1369                    let mut diagnostic_highlight = HighlightStyle::default();
1370
1371                    if chunk.is_unnecessary {
1372                        diagnostic_highlight.fade_out = Some(style.unnecessary_code_fade);
1373                    }
1374
1375                    if let Some(severity) = chunk.diagnostic_severity {
1376                        // Omit underlines for HINT/INFO diagnostics on 'unnecessary' code.
1377                        if severity <= DiagnosticSeverity::WARNING || !chunk.is_unnecessary {
1378                            let diagnostic_style = super::diagnostic_style(severity, true, style);
1379                            diagnostic_highlight.underline = Some(Underline {
1380                                color: Some(diagnostic_style.message.text.color),
1381                                thickness: 1.0.into(),
1382                                squiggly: true,
1383                            });
1384                        }
1385                    }
1386
1387                    if let Some(highlight_style) = highlight_style.as_mut() {
1388                        highlight_style.highlight(diagnostic_highlight);
1389                    } else {
1390                        highlight_style = Some(diagnostic_highlight);
1391                    }
1392
1393                    (chunk.text, highlight_style)
1394                });
1395            layout_highlighted_chunks(
1396                chunks,
1397                &style.text,
1398                cx.text_layout_cache,
1399                cx.font_cache,
1400                MAX_LINE_LEN,
1401                rows.len() as usize,
1402            )
1403        }
1404    }
1405
1406    #[allow(clippy::too_many_arguments)]
1407    fn layout_blocks(
1408        &mut self,
1409        rows: Range<u32>,
1410        snapshot: &EditorSnapshot,
1411        editor_width: f32,
1412        scroll_width: f32,
1413        gutter_padding: f32,
1414        gutter_width: f32,
1415        em_width: f32,
1416        text_x: f32,
1417        line_height: f32,
1418        style: &EditorStyle,
1419        line_layouts: &[text_layout::Line],
1420        include_root: bool,
1421        editor: &mut Editor,
1422        cx: &mut LayoutContext,
1423    ) -> (f32, Vec<BlockLayout>) {
1424        let tooltip_style = cx.global::<Settings>().theme.tooltip.clone();
1425        let scroll_x = snapshot.scroll_anchor.offset.x();
1426        let (fixed_blocks, non_fixed_blocks) = snapshot
1427            .blocks_in_range(rows.clone())
1428            .partition::<Vec<_>, _>(|(_, block)| match block {
1429                TransformBlock::ExcerptHeader { .. } => false,
1430                TransformBlock::Custom(block) => block.style() == BlockStyle::Fixed,
1431            });
1432        let mut render_block = |block: &TransformBlock, width: f32| {
1433            let mut element = match block {
1434                TransformBlock::Custom(block) => {
1435                    let align_to = block
1436                        .position()
1437                        .to_point(&snapshot.buffer_snapshot)
1438                        .to_display_point(snapshot);
1439                    let anchor_x = text_x
1440                        + if rows.contains(&align_to.row()) {
1441                            line_layouts[(align_to.row() - rows.start) as usize]
1442                                .x_for_index(align_to.column() as usize)
1443                        } else {
1444                            layout_line(align_to.row(), snapshot, style, cx.text_layout_cache)
1445                                .x_for_index(align_to.column() as usize)
1446                        };
1447
1448                    cx.render(&editor, |_, cx| {
1449                        block.render(&mut BlockContext {
1450                            cx,
1451                            anchor_x,
1452                            gutter_padding,
1453                            line_height,
1454                            scroll_x,
1455                            gutter_width,
1456                            em_width,
1457                        })
1458                    })
1459                }
1460                TransformBlock::ExcerptHeader {
1461                    id,
1462                    buffer,
1463                    range,
1464                    starts_new_buffer,
1465                    ..
1466                } => {
1467                    let id = *id;
1468                    let jump_icon = project::File::from_dyn(buffer.file()).map(|file| {
1469                        let jump_position = range
1470                            .primary
1471                            .as_ref()
1472                            .map_or(range.context.start, |primary| primary.start);
1473                        let jump_action = crate::Jump {
1474                            path: ProjectPath {
1475                                worktree_id: file.worktree_id(cx),
1476                                path: file.path.clone(),
1477                            },
1478                            position: language::ToPoint::to_point(&jump_position, buffer),
1479                            anchor: jump_position,
1480                        };
1481
1482                        enum JumpIcon {}
1483                        cx.render(&editor, |_, cx| {
1484                            MouseEventHandler::<JumpIcon>::new(id.into(), cx, |state, _| {
1485                                let style = style.jump_icon.style_for(state, false);
1486                                Svg::new("icons/arrow_up_right_8.svg")
1487                                    .with_color(style.color)
1488                                    .constrained()
1489                                    .with_width(style.icon_width)
1490                                    .aligned()
1491                                    .contained()
1492                                    .with_style(style.container)
1493                                    .constrained()
1494                                    .with_width(style.button_width)
1495                                    .with_height(style.button_width)
1496                                    .boxed()
1497                            })
1498                            .with_cursor_style(CursorStyle::PointingHand)
1499                            .on_click(MouseButton::Left, move |_, cx| {
1500                                cx.dispatch_action(jump_action.clone())
1501                            })
1502                            .with_tooltip::<JumpIcon, _>(
1503                                id.into(),
1504                                "Jump to Buffer".to_string(),
1505                                Some(Box::new(crate::OpenExcerpts)),
1506                                tooltip_style.clone(),
1507                                cx,
1508                            )
1509                            .aligned()
1510                            .flex_float()
1511                            .boxed()
1512                        })
1513                    });
1514
1515                    if *starts_new_buffer {
1516                        let style = &self.style.diagnostic_path_header;
1517                        let font_size =
1518                            (style.text_scale_factor * self.style.text.font_size).round();
1519
1520                        let path = buffer.resolve_file_path(cx, include_root);
1521                        let mut filename = None;
1522                        let mut parent_path = None;
1523                        // Can't use .and_then() because `.file_name()` and `.parent()` return references :(
1524                        if let Some(path) = path {
1525                            filename = path.file_name().map(|f| f.to_string_lossy().to_string());
1526                            parent_path =
1527                                path.parent().map(|p| p.to_string_lossy().to_string() + "/");
1528                        }
1529
1530                        Flex::row()
1531                            .with_child(
1532                                Label::new(
1533                                    filename.unwrap_or_else(|| "untitled".to_string()),
1534                                    style.filename.text.clone().with_font_size(font_size),
1535                                )
1536                                .contained()
1537                                .with_style(style.filename.container)
1538                                .aligned()
1539                                .boxed(),
1540                            )
1541                            .with_children(parent_path.map(|path| {
1542                                Label::new(path, style.path.text.clone().with_font_size(font_size))
1543                                    .contained()
1544                                    .with_style(style.path.container)
1545                                    .aligned()
1546                                    .boxed()
1547                            }))
1548                            .with_children(jump_icon)
1549                            .contained()
1550                            .with_style(style.container)
1551                            .with_padding_left(gutter_padding)
1552                            .with_padding_right(gutter_padding)
1553                            .expanded()
1554                            .named("path header block")
1555                    } else {
1556                        let text_style = self.style.text.clone();
1557                        Flex::row()
1558                            .with_child(Label::new("", text_style).boxed())
1559                            .with_children(jump_icon)
1560                            .contained()
1561                            .with_padding_left(gutter_padding)
1562                            .with_padding_right(gutter_padding)
1563                            .expanded()
1564                            .named("collapsed context")
1565                    }
1566                }
1567            };
1568
1569            element.layout(
1570                SizeConstraint {
1571                    min: Vector2F::zero(),
1572                    max: vec2f(width, block.height() as f32 * line_height),
1573                },
1574                editor,
1575                cx,
1576            );
1577            element
1578        };
1579
1580        let mut fixed_block_max_width = 0f32;
1581        let mut blocks = Vec::new();
1582        for (row, block) in fixed_blocks {
1583            let element = render_block(block, f32::INFINITY);
1584            fixed_block_max_width = fixed_block_max_width.max(element.size().x() + em_width);
1585            blocks.push(BlockLayout {
1586                row,
1587                element,
1588                style: BlockStyle::Fixed,
1589            });
1590        }
1591        for (row, block) in non_fixed_blocks {
1592            let style = match block {
1593                TransformBlock::Custom(block) => block.style(),
1594                TransformBlock::ExcerptHeader { .. } => BlockStyle::Sticky,
1595            };
1596            let width = match style {
1597                BlockStyle::Sticky => editor_width,
1598                BlockStyle::Flex => editor_width
1599                    .max(fixed_block_max_width)
1600                    .max(gutter_width + scroll_width),
1601                BlockStyle::Fixed => unreachable!(),
1602            };
1603            let element = render_block(block, width);
1604            blocks.push(BlockLayout {
1605                row,
1606                element,
1607                style,
1608            });
1609        }
1610        (
1611            scroll_width.max(fixed_block_max_width - gutter_width),
1612            blocks,
1613        )
1614    }
1615}
1616
1617impl Element for EditorElement {
1618    type LayoutState = LayoutState;
1619    type PaintState = ();
1620
1621    fn layout(
1622        &mut self,
1623        constraint: SizeConstraint,
1624        cx: &mut LayoutContext,
1625    ) -> (Vector2F, Self::LayoutState) {
1626        let mut size = constraint.max;
1627        if size.x().is_infinite() {
1628            unimplemented!("we don't yet handle an infinite width constraint on buffer elements");
1629        }
1630
1631        let snapshot = self.snapshot(cx.app);
1632        let style = self.style.clone();
1633        let line_height = style.text.line_height(cx.font_cache);
1634
1635        let gutter_padding;
1636        let gutter_width;
1637        let gutter_margin;
1638        if snapshot.mode == EditorMode::Full {
1639            gutter_padding = style.text.em_width(cx.font_cache) * style.gutter_padding_factor;
1640            gutter_width = self.max_line_number_width(&snapshot, cx) + gutter_padding * 2.0;
1641            gutter_margin = -style.text.descent(cx.font_cache);
1642        } else {
1643            gutter_padding = 0.0;
1644            gutter_width = 0.0;
1645            gutter_margin = 0.0;
1646        };
1647
1648        let text_width = size.x() - gutter_width;
1649        let em_width = style.text.em_width(cx.font_cache);
1650        let em_advance = style.text.em_advance(cx.font_cache);
1651        let overscroll = vec2f(em_width, 0.);
1652        let snapshot = self.update_view(cx.app, |view, cx| {
1653            view.set_visible_line_count(size.y() / line_height);
1654
1655            let editor_width = text_width - gutter_margin - overscroll.x() - em_width;
1656            let wrap_width = match view.soft_wrap_mode(cx) {
1657                SoftWrap::None => (MAX_LINE_LEN / 2) as f32 * em_advance,
1658                SoftWrap::EditorWidth => editor_width,
1659                SoftWrap::Column(column) => editor_width.min(column as f32 * em_advance),
1660            };
1661
1662            if view.set_wrap_width(Some(wrap_width), cx) {
1663                view.snapshot(cx)
1664            } else {
1665                snapshot
1666            }
1667        });
1668
1669        let scroll_height = (snapshot.max_point().row() + 1) as f32 * line_height;
1670        if let EditorMode::AutoHeight { max_lines } = snapshot.mode {
1671            size.set_y(
1672                scroll_height
1673                    .min(constraint.max_along(Axis::Vertical))
1674                    .max(constraint.min_along(Axis::Vertical))
1675                    .min(line_height * max_lines as f32),
1676            )
1677        } else if let EditorMode::SingleLine = snapshot.mode {
1678            size.set_y(
1679                line_height
1680                    .min(constraint.max_along(Axis::Vertical))
1681                    .max(constraint.min_along(Axis::Vertical)),
1682            )
1683        } else if size.y().is_infinite() {
1684            size.set_y(scroll_height);
1685        }
1686        let gutter_size = vec2f(gutter_width, size.y());
1687        let text_size = vec2f(text_width, size.y());
1688
1689        let (autoscroll_horizontally, mut snapshot) = self.update_view(cx.app, |view, cx| {
1690            let autoscroll_horizontally = view.autoscroll_vertically(size.y(), line_height, cx);
1691            let snapshot = view.snapshot(cx);
1692            (autoscroll_horizontally, snapshot)
1693        });
1694
1695        let scroll_position = snapshot.scroll_position();
1696        // The scroll position is a fractional point, the whole number of which represents
1697        // the top of the window in terms of display rows.
1698        let start_row = scroll_position.y() as u32;
1699        let height_in_lines = size.y() / line_height;
1700        let max_row = snapshot.max_point().row();
1701
1702        // Add 1 to ensure selections bleed off screen
1703        let end_row = 1 + cmp::min(
1704            (scroll_position.y() + height_in_lines).ceil() as u32,
1705            max_row,
1706        );
1707
1708        let start_anchor = if start_row == 0 {
1709            Anchor::min()
1710        } else {
1711            snapshot
1712                .buffer_snapshot
1713                .anchor_before(DisplayPoint::new(start_row, 0).to_offset(&snapshot, Bias::Left))
1714        };
1715        let end_anchor = if end_row > max_row {
1716            Anchor::max()
1717        } else {
1718            snapshot
1719                .buffer_snapshot
1720                .anchor_before(DisplayPoint::new(end_row, 0).to_offset(&snapshot, Bias::Right))
1721        };
1722
1723        let mut selections: Vec<(ReplicaId, Vec<SelectionLayout>)> = Vec::new();
1724        let mut active_rows = BTreeMap::new();
1725        let mut highlighted_rows = None;
1726        let mut highlighted_ranges = Vec::new();
1727        let mut fold_ranges = Vec::new();
1728        let mut show_scrollbars = false;
1729        let mut include_root = false;
1730        let mut is_singleton = false;
1731        self.update_view(cx.app, |view, cx| {
1732            is_singleton = view.is_singleton(cx);
1733
1734            let display_map = view.display_map.update(cx, |map, cx| map.snapshot(cx));
1735
1736            highlighted_rows = view.highlighted_rows();
1737            let theme = cx.global::<Settings>().theme.as_ref();
1738            highlighted_ranges =
1739                view.background_highlights_in_range(start_anchor..end_anchor, &display_map, theme);
1740
1741            fold_ranges.extend(
1742                snapshot
1743                    .folds_in_range(start_anchor..end_anchor)
1744                    .map(|anchor| {
1745                        let start = anchor.start.to_point(&snapshot.buffer_snapshot);
1746                        (
1747                            start.row,
1748                            start.to_display_point(&snapshot.display_snapshot)
1749                                ..anchor.end.to_display_point(&snapshot),
1750                        )
1751                    }),
1752            );
1753
1754            let mut remote_selections = HashMap::default();
1755            for (replica_id, line_mode, cursor_shape, selection) in display_map
1756                .buffer_snapshot
1757                .remote_selections_in_range(&(start_anchor..end_anchor))
1758            {
1759                // The local selections match the leader's selections.
1760                if Some(replica_id) == view.leader_replica_id {
1761                    continue;
1762                }
1763                remote_selections
1764                    .entry(replica_id)
1765                    .or_insert(Vec::new())
1766                    .push(SelectionLayout::new(
1767                        selection,
1768                        line_mode,
1769                        cursor_shape,
1770                        &display_map,
1771                    ));
1772            }
1773            selections.extend(remote_selections);
1774
1775            if view.show_local_selections {
1776                let mut local_selections = view
1777                    .selections
1778                    .disjoint_in_range(start_anchor..end_anchor, cx);
1779                local_selections.extend(view.selections.pending(cx));
1780                for selection in &local_selections {
1781                    let is_empty = selection.start == selection.end;
1782                    let selection_start = snapshot.prev_line_boundary(selection.start).1;
1783                    let selection_end = snapshot.next_line_boundary(selection.end).1;
1784                    for row in cmp::max(selection_start.row(), start_row)
1785                        ..=cmp::min(selection_end.row(), end_row)
1786                    {
1787                        let contains_non_empty_selection =
1788                            active_rows.entry(row).or_insert(!is_empty);
1789                        *contains_non_empty_selection |= !is_empty;
1790                    }
1791                }
1792
1793                // Render the local selections in the leader's color when following.
1794                let local_replica_id = view
1795                    .leader_replica_id
1796                    .unwrap_or_else(|| view.replica_id(cx));
1797
1798                selections.push((
1799                    local_replica_id,
1800                    local_selections
1801                        .into_iter()
1802                        .map(|selection| {
1803                            SelectionLayout::new(
1804                                selection,
1805                                view.selections.line_mode,
1806                                view.cursor_shape,
1807                                &display_map,
1808                            )
1809                        })
1810                        .collect(),
1811                ));
1812            }
1813
1814            show_scrollbars = view.scroll_manager.scrollbars_visible();
1815            include_root = view
1816                .project
1817                .as_ref()
1818                .map(|project| project.read(cx).visible_worktrees(cx).count() > 1)
1819                .unwrap_or_default()
1820        });
1821
1822        let fold_ranges: Vec<(BufferRow, Range<DisplayPoint>, Color)> = fold_ranges
1823            .into_iter()
1824            .map(|(id, fold)| {
1825                let color = self
1826                    .style
1827                    .folds
1828                    .ellipses
1829                    .background
1830                    .style_for(&mut cx.mouse_state::<FoldMarkers>(id as usize), false)
1831                    .color;
1832
1833                (id, fold, color)
1834            })
1835            .collect();
1836
1837        let (line_number_layouts, fold_statuses) = self.layout_line_numbers(
1838            start_row..end_row,
1839            &active_rows,
1840            is_singleton,
1841            &snapshot,
1842            cx,
1843        );
1844
1845        let display_hunks = self.layout_git_gutters(start_row..end_row, &snapshot);
1846
1847        let scrollbar_row_range = scroll_position.y()..(scroll_position.y() + height_in_lines);
1848
1849        let mut max_visible_line_width = 0.0;
1850        let line_layouts = self.layout_lines(start_row..end_row, &snapshot, cx);
1851        for line in &line_layouts {
1852            if line.width() > max_visible_line_width {
1853                max_visible_line_width = line.width();
1854            }
1855        }
1856
1857        let style = self.style.clone();
1858        let longest_line_width = layout_line(
1859            snapshot.longest_row(),
1860            &snapshot,
1861            &style,
1862            cx.text_layout_cache,
1863        )
1864        .width();
1865        let scroll_width = longest_line_width.max(max_visible_line_width) + overscroll.x();
1866        let em_width = style.text.em_width(cx.font_cache);
1867        let (scroll_width, blocks) = self.layout_blocks(
1868            start_row..end_row,
1869            &snapshot,
1870            size.x(),
1871            scroll_width,
1872            gutter_padding,
1873            gutter_width,
1874            em_width,
1875            gutter_width + gutter_margin,
1876            line_height,
1877            &style,
1878            &line_layouts,
1879            include_root,
1880            editor,
1881            cx,
1882        );
1883
1884        let scroll_max = vec2f(
1885            ((scroll_width - text_size.x()) / em_width).max(0.0),
1886            max_row as f32,
1887        );
1888
1889        self.update_view(cx.app, |view, cx| {
1890            let clamped = view.scroll_manager.clamp_scroll_left(scroll_max.x());
1891
1892            let autoscrolled = if autoscroll_horizontally {
1893                view.autoscroll_horizontally(
1894                    start_row,
1895                    text_size.x(),
1896                    scroll_width,
1897                    em_width,
1898                    &line_layouts,
1899                    cx,
1900                )
1901            } else {
1902                false
1903            };
1904
1905            if clamped || autoscrolled {
1906                snapshot = view.snapshot(cx);
1907            }
1908        });
1909
1910        let mut context_menu = None;
1911        let mut code_actions_indicator = None;
1912        let mut hover = None;
1913        let mut mode = EditorMode::Full;
1914        let mut fold_indicators = cx.render(&self.view.upgrade(cx).unwrap(), |view, cx| {
1915            let newest_selection_head = view
1916                .selections
1917                .newest::<usize>(cx)
1918                .head()
1919                .to_display_point(&snapshot);
1920
1921            let style = view.style(cx);
1922            if (start_row..end_row).contains(&newest_selection_head.row()) {
1923                if view.context_menu_visible() {
1924                    context_menu =
1925                        view.render_context_menu(newest_selection_head, style.clone(), cx);
1926                }
1927
1928                let active = matches!(view.context_menu, Some(crate::ContextMenu::CodeActions(_)));
1929
1930                code_actions_indicator = view
1931                    .render_code_actions_indicator(&style, active, cx)
1932                    .map(|indicator| (newest_selection_head.row(), indicator));
1933            }
1934
1935            let visible_rows = start_row..start_row + line_layouts.len() as u32;
1936            hover = view.hover_state.render(&snapshot, &style, visible_rows, cx);
1937            mode = view.mode;
1938
1939            view.render_fold_indicators(
1940                fold_statuses,
1941                &style,
1942                view.gutter_hovered,
1943                line_height,
1944                gutter_margin,
1945                cx,
1946            )
1947        });
1948
1949        if let Some((_, context_menu)) = context_menu.as_mut() {
1950            context_menu.layout(
1951                SizeConstraint {
1952                    min: Vector2F::zero(),
1953                    max: vec2f(
1954                        cx.window_size.x() * 0.7,
1955                        (12. * line_height).min((size.y() - line_height) / 2.),
1956                    ),
1957                },
1958                editor,
1959                cx,
1960            );
1961        }
1962
1963        if let Some((_, indicator)) = code_actions_indicator.as_mut() {
1964            indicator.layout(
1965                SizeConstraint::strict_along(
1966                    Axis::Vertical,
1967                    line_height * style.code_actions.vertical_scale,
1968                ),
1969                editor,
1970                cx,
1971            );
1972        }
1973
1974        for fold_indicator in fold_indicators.iter_mut() {
1975            if let Some(indicator) = fold_indicator.as_mut() {
1976                indicator.layout(
1977                    SizeConstraint::strict_along(
1978                        Axis::Vertical,
1979                        line_height * style.code_actions.vertical_scale,
1980                    ),
1981                    cx,
1982                );
1983            }
1984        }
1985
1986        if let Some((_, hover_popovers)) = hover.as_mut() {
1987            for hover_popover in hover_popovers.iter_mut() {
1988                hover_popover.layout(
1989                    SizeConstraint {
1990                        min: Vector2F::zero(),
1991                        max: vec2f(
1992                            (120. * em_width) // Default size
1993                                .min(size.x() / 2.) // Shrink to half of the editor width
1994                                .max(MIN_POPOVER_CHARACTER_WIDTH * em_width), // Apply minimum width of 20 characters
1995                            (16. * line_height) // Default size
1996                                .min(size.y() / 2.) // Shrink to half of the editor height
1997                                .max(MIN_POPOVER_LINE_HEIGHT * line_height), // Apply minimum height of 4 lines
1998                        ),
1999                    },
2000                    cx,
2001                );
2002            }
2003        }
2004
2005        (
2006            size,
2007            LayoutState {
2008                mode,
2009                position_map: Arc::new(PositionMap {
2010                    size,
2011                    scroll_max,
2012                    line_layouts,
2013                    line_height,
2014                    em_width,
2015                    em_advance,
2016                    snapshot,
2017                }),
2018                visible_display_row_range: start_row..end_row,
2019                gutter_size,
2020                gutter_padding,
2021                text_size,
2022                scrollbar_row_range,
2023                show_scrollbars,
2024                max_row,
2025                gutter_margin,
2026                active_rows,
2027                highlighted_rows,
2028                highlighted_ranges,
2029                fold_ranges,
2030                line_number_layouts,
2031                display_hunks,
2032                blocks,
2033                selections,
2034                context_menu,
2035                code_actions_indicator,
2036                fold_indicators,
2037                hover_popovers: hover,
2038            },
2039        )
2040    }
2041
2042    fn paint(
2043        &mut self,
2044        bounds: RectF,
2045        visible_bounds: RectF,
2046        layout: &mut Self::LayoutState,
2047        cx: &mut PaintContext,
2048    ) -> Self::PaintState {
2049        let visible_bounds = bounds.intersection(visible_bounds).unwrap_or_default();
2050        scene.push_layer(Some(visible_bounds));
2051
2052        let gutter_bounds = RectF::new(bounds.origin(), layout.gutter_size);
2053        let text_bounds = RectF::new(
2054            bounds.origin() + vec2f(layout.gutter_size.x(), 0.0),
2055            layout.text_size,
2056        );
2057
2058        Self::attach_mouse_handlers(
2059            &self.view,
2060            &layout.position_map,
2061            layout.hover_popovers.is_some(),
2062            visible_bounds,
2063            text_bounds,
2064            gutter_bounds,
2065            bounds,
2066            cx,
2067        );
2068
2069        self.paint_background(scene, gutter_bounds, text_bounds, layout, cx);
2070        if layout.gutter_size.x() > 0. {
2071            self.paint_gutter(scene, gutter_bounds, visible_bounds, layout, editor, cx);
2072        }
2073        self.paint_text(scene, text_bounds, visible_bounds, layout, editor, cx);
2074
2075        scene.push_layer(Some(bounds));
2076        if !layout.blocks.is_empty() {
2077            self.paint_blocks(scene, bounds, visible_bounds, layout, editor, cx);
2078        }
2079        self.paint_scrollbar(scene, bounds, layout, cx);
2080        scene.pop_layer();
2081
2082        scene.pop_layer();
2083    }
2084
2085    fn rect_for_text_range(
2086        &self,
2087        range_utf16: Range<usize>,
2088        bounds: RectF,
2089        _: RectF,
2090        layout: &Self::LayoutState,
2091        _: &Self::PaintState,
2092        _: &gpui::MeasurementContext,
2093    ) -> Option<RectF> {
2094        let text_bounds = RectF::new(
2095            bounds.origin() + vec2f(layout.gutter_size.x(), 0.0),
2096            layout.text_size,
2097        );
2098        let content_origin = text_bounds.origin() + vec2f(layout.gutter_margin, 0.);
2099        let scroll_position = layout.position_map.snapshot.scroll_position();
2100        let start_row = scroll_position.y() as u32;
2101        let scroll_top = scroll_position.y() * layout.position_map.line_height;
2102        let scroll_left = scroll_position.x() * layout.position_map.em_width;
2103
2104        let range_start = OffsetUtf16(range_utf16.start)
2105            .to_display_point(&layout.position_map.snapshot.display_snapshot);
2106        if range_start.row() < start_row {
2107            return None;
2108        }
2109
2110        let line = layout
2111            .position_map
2112            .line_layouts
2113            .get((range_start.row() - start_row) as usize)?;
2114        let range_start_x = line.x_for_index(range_start.column() as usize);
2115        let range_start_y = range_start.row() as f32 * layout.position_map.line_height;
2116        Some(RectF::new(
2117            content_origin
2118                + vec2f(
2119                    range_start_x,
2120                    range_start_y + layout.position_map.line_height,
2121                )
2122                - vec2f(scroll_left, scroll_top),
2123            vec2f(
2124                layout.position_map.em_width,
2125                layout.position_map.line_height,
2126            ),
2127        ))
2128    }
2129
2130    fn debug(
2131        &self,
2132        bounds: RectF,
2133        _: &Self::LayoutState,
2134        _: &Self::PaintState,
2135        _: &gpui::DebugContext,
2136    ) -> json::Value {
2137        json!({
2138            "type": "BufferElement",
2139            "bounds": bounds.to_json()
2140        })
2141    }
2142}
2143
2144type BufferRow = u32;
2145
2146pub struct LayoutState {
2147    position_map: Arc<PositionMap>,
2148    gutter_size: Vector2F,
2149    gutter_padding: f32,
2150    gutter_margin: f32,
2151    text_size: Vector2F,
2152    mode: EditorMode,
2153    visible_display_row_range: Range<u32>,
2154    active_rows: BTreeMap<u32, bool>,
2155    highlighted_rows: Option<Range<u32>>,
2156    line_number_layouts: Vec<Option<text_layout::Line>>,
2157    display_hunks: Vec<DisplayDiffHunk>,
2158    blocks: Vec<BlockLayout>,
2159    highlighted_ranges: Vec<(Range<DisplayPoint>, Color)>,
2160    fold_ranges: Vec<(BufferRow, Range<DisplayPoint>, Color)>,
2161    selections: Vec<(ReplicaId, Vec<SelectionLayout>)>,
2162    scrollbar_row_range: Range<f32>,
2163    show_scrollbars: bool,
2164    max_row: u32,
2165    context_menu: Option<(DisplayPoint, ElementBox)>,
2166    code_actions_indicator: Option<(u32, ElementBox)>,
2167    hover_popovers: Option<(DisplayPoint, Vec<ElementBox>)>,
2168    fold_indicators: Vec<Option<ElementBox>>,
2169}
2170
2171pub struct PositionMap {
2172    size: Vector2F,
2173    line_height: f32,
2174    scroll_max: Vector2F,
2175    em_width: f32,
2176    em_advance: f32,
2177    line_layouts: Vec<text_layout::Line>,
2178    snapshot: EditorSnapshot,
2179}
2180
2181impl PositionMap {
2182    /// Returns two display points:
2183    /// 1. The nearest *valid* position in the editor
2184    /// 2. An unclipped, potentially *invalid* position that maps directly to
2185    ///    the given pixel position.
2186    fn point_for_position(
2187        &self,
2188        text_bounds: RectF,
2189        position: Vector2F,
2190    ) -> (DisplayPoint, DisplayPoint) {
2191        let scroll_position = self.snapshot.scroll_position();
2192        let position = position - text_bounds.origin();
2193        let y = position.y().max(0.0).min(self.size.y());
2194        let x = position.x() + (scroll_position.x() * self.em_width);
2195        let row = (y / self.line_height + scroll_position.y()) as u32;
2196        let (column, x_overshoot) = if let Some(line) = self
2197            .line_layouts
2198            .get(row as usize - scroll_position.y() as usize)
2199        {
2200            if let Some(ix) = line.index_for_x(x) {
2201                (ix as u32, 0.0)
2202            } else {
2203                (line.len() as u32, 0f32.max(x - line.width()))
2204            }
2205        } else {
2206            (0, x)
2207        };
2208
2209        let mut target_point = DisplayPoint::new(row, column);
2210        let point = self.snapshot.clip_point(target_point, Bias::Left);
2211        *target_point.column_mut() += (x_overshoot / self.em_advance) as u32;
2212
2213        (point, target_point)
2214    }
2215}
2216
2217struct BlockLayout {
2218    row: u32,
2219    element: ElementBox,
2220    style: BlockStyle,
2221}
2222
2223fn layout_line(
2224    row: u32,
2225    snapshot: &EditorSnapshot,
2226    style: &EditorStyle,
2227    layout_cache: &TextLayoutCache,
2228) -> text_layout::Line {
2229    let mut line = snapshot.line(row);
2230
2231    if line.len() > MAX_LINE_LEN {
2232        let mut len = MAX_LINE_LEN;
2233        while !line.is_char_boundary(len) {
2234            len -= 1;
2235        }
2236
2237        line.truncate(len);
2238    }
2239
2240    layout_cache.layout_str(
2241        &line,
2242        style.text.font_size,
2243        &[(
2244            snapshot.line_len(row) as usize,
2245            RunStyle {
2246                font_id: style.text.font_id,
2247                color: Color::black(),
2248                underline: Default::default(),
2249            },
2250        )],
2251    )
2252}
2253
2254#[derive(Debug)]
2255pub struct Cursor {
2256    origin: Vector2F,
2257    block_width: f32,
2258    line_height: f32,
2259    color: Color,
2260    shape: CursorShape,
2261    block_text: Option<Line>,
2262}
2263
2264impl Cursor {
2265    pub fn new(
2266        origin: Vector2F,
2267        block_width: f32,
2268        line_height: f32,
2269        color: Color,
2270        shape: CursorShape,
2271        block_text: Option<Line>,
2272    ) -> Cursor {
2273        Cursor {
2274            origin,
2275            block_width,
2276            line_height,
2277            color,
2278            shape,
2279            block_text,
2280        }
2281    }
2282
2283    pub fn bounding_rect(&self, origin: Vector2F) -> RectF {
2284        RectF::new(
2285            self.origin + origin,
2286            vec2f(self.block_width, self.line_height),
2287        )
2288    }
2289
2290    pub fn paint(&self, scene: &mut SceneBuilder, origin: Vector2F, cx: &mut AppContext) {
2291        let bounds = match self.shape {
2292            CursorShape::Bar => RectF::new(self.origin + origin, vec2f(2.0, self.line_height)),
2293            CursorShape::Block | CursorShape::Hollow => RectF::new(
2294                self.origin + origin,
2295                vec2f(self.block_width, self.line_height),
2296            ),
2297            CursorShape::Underscore => RectF::new(
2298                self.origin + origin + Vector2F::new(0.0, self.line_height - 2.0),
2299                vec2f(self.block_width, 2.0),
2300            ),
2301        };
2302
2303        //Draw background or border quad
2304        if matches!(self.shape, CursorShape::Hollow) {
2305            scene.push_quad(Quad {
2306                bounds,
2307                background: None,
2308                border: Border::all(1., self.color),
2309                corner_radius: 0.,
2310            });
2311        } else {
2312            scene.push_quad(Quad {
2313                bounds,
2314                background: Some(self.color),
2315                border: Default::default(),
2316                corner_radius: 0.,
2317            });
2318        }
2319
2320        if let Some(block_text) = &self.block_text {
2321            block_text.paint(scene, self.origin + origin, bounds, self.line_height, cx);
2322        }
2323    }
2324
2325    pub fn shape(&self) -> CursorShape {
2326        self.shape
2327    }
2328}
2329
2330#[derive(Debug)]
2331pub struct HighlightedRange {
2332    pub start_y: f32,
2333    pub line_height: f32,
2334    pub lines: Vec<HighlightedRangeLine>,
2335    pub color: Color,
2336    pub corner_radius: f32,
2337}
2338
2339#[derive(Debug)]
2340pub struct HighlightedRangeLine {
2341    pub start_x: f32,
2342    pub end_x: f32,
2343}
2344
2345impl HighlightedRange {
2346    pub fn paint(&self, bounds: RectF, scene: &mut SceneBuilder) {
2347        if self.lines.len() >= 2 && self.lines[0].start_x > self.lines[1].end_x {
2348            self.paint_lines(self.start_y, &self.lines[0..1], bounds, scene);
2349            self.paint_lines(
2350                self.start_y + self.line_height,
2351                &self.lines[1..],
2352                bounds,
2353                scene,
2354            );
2355        } else {
2356            self.paint_lines(self.start_y, &self.lines, bounds, scene);
2357        }
2358    }
2359
2360    fn paint_lines(
2361        &self,
2362        start_y: f32,
2363        lines: &[HighlightedRangeLine],
2364        bounds: RectF,
2365        scene: &mut SceneBuilder,
2366    ) {
2367        if lines.is_empty() {
2368            return;
2369        }
2370
2371        let mut path = PathBuilder::new();
2372        let first_line = lines.first().unwrap();
2373        let last_line = lines.last().unwrap();
2374
2375        let first_top_left = vec2f(first_line.start_x, start_y);
2376        let first_top_right = vec2f(first_line.end_x, start_y);
2377
2378        let curve_height = vec2f(0., self.corner_radius);
2379        let curve_width = |start_x: f32, end_x: f32| {
2380            let max = (end_x - start_x) / 2.;
2381            let width = if max < self.corner_radius {
2382                max
2383            } else {
2384                self.corner_radius
2385            };
2386
2387            vec2f(width, 0.)
2388        };
2389
2390        let top_curve_width = curve_width(first_line.start_x, first_line.end_x);
2391        path.reset(first_top_right - top_curve_width);
2392        path.curve_to(first_top_right + curve_height, first_top_right);
2393
2394        let mut iter = lines.iter().enumerate().peekable();
2395        while let Some((ix, line)) = iter.next() {
2396            let bottom_right = vec2f(line.end_x, start_y + (ix + 1) as f32 * self.line_height);
2397
2398            if let Some((_, next_line)) = iter.peek() {
2399                let next_top_right = vec2f(next_line.end_x, bottom_right.y());
2400
2401                match next_top_right.x().partial_cmp(&bottom_right.x()).unwrap() {
2402                    Ordering::Equal => {
2403                        path.line_to(bottom_right);
2404                    }
2405                    Ordering::Less => {
2406                        let curve_width = curve_width(next_top_right.x(), bottom_right.x());
2407                        path.line_to(bottom_right - curve_height);
2408                        if self.corner_radius > 0. {
2409                            path.curve_to(bottom_right - curve_width, bottom_right);
2410                        }
2411                        path.line_to(next_top_right + curve_width);
2412                        if self.corner_radius > 0. {
2413                            path.curve_to(next_top_right + curve_height, next_top_right);
2414                        }
2415                    }
2416                    Ordering::Greater => {
2417                        let curve_width = curve_width(bottom_right.x(), next_top_right.x());
2418                        path.line_to(bottom_right - curve_height);
2419                        if self.corner_radius > 0. {
2420                            path.curve_to(bottom_right + curve_width, bottom_right);
2421                        }
2422                        path.line_to(next_top_right - curve_width);
2423                        if self.corner_radius > 0. {
2424                            path.curve_to(next_top_right + curve_height, next_top_right);
2425                        }
2426                    }
2427                }
2428            } else {
2429                let curve_width = curve_width(line.start_x, line.end_x);
2430                path.line_to(bottom_right - curve_height);
2431                if self.corner_radius > 0. {
2432                    path.curve_to(bottom_right - curve_width, bottom_right);
2433                }
2434
2435                let bottom_left = vec2f(line.start_x, bottom_right.y());
2436                path.line_to(bottom_left + curve_width);
2437                if self.corner_radius > 0. {
2438                    path.curve_to(bottom_left - curve_height, bottom_left);
2439                }
2440            }
2441        }
2442
2443        if first_line.start_x > last_line.start_x {
2444            let curve_width = curve_width(last_line.start_x, first_line.start_x);
2445            let second_top_left = vec2f(last_line.start_x, start_y + self.line_height);
2446            path.line_to(second_top_left + curve_height);
2447            if self.corner_radius > 0. {
2448                path.curve_to(second_top_left + curve_width, second_top_left);
2449            }
2450            let first_bottom_left = vec2f(first_line.start_x, second_top_left.y());
2451            path.line_to(first_bottom_left - curve_width);
2452            if self.corner_radius > 0. {
2453                path.curve_to(first_bottom_left - curve_height, first_bottom_left);
2454            }
2455        }
2456
2457        path.line_to(first_top_left + curve_height);
2458        if self.corner_radius > 0. {
2459            path.curve_to(first_top_left + top_curve_width, first_top_left);
2460        }
2461        path.line_to(first_top_right - top_curve_width);
2462
2463        scene.push_path(path.build(self.color, Some(bounds)));
2464    }
2465}
2466
2467pub fn position_to_display_point(
2468    position: Vector2F,
2469    text_bounds: RectF,
2470    position_map: &PositionMap,
2471) -> Option<DisplayPoint> {
2472    if text_bounds.contains_point(position) {
2473        let (point, target_point) = position_map.point_for_position(text_bounds, position);
2474        if point == target_point {
2475            Some(point)
2476        } else {
2477            None
2478        }
2479    } else {
2480        None
2481    }
2482}
2483
2484pub fn range_to_bounds(
2485    range: &Range<DisplayPoint>,
2486    content_origin: Vector2F,
2487    scroll_left: f32,
2488    scroll_top: f32,
2489    visible_row_range: &Range<u32>,
2490    line_end_overshoot: f32,
2491    position_map: &PositionMap,
2492) -> impl Iterator<Item = RectF> {
2493    let mut bounds: SmallVec<[RectF; 1]> = SmallVec::new();
2494
2495    if range.start == range.end {
2496        return bounds.into_iter();
2497    }
2498
2499    let start_row = visible_row_range.start;
2500    let end_row = visible_row_range.end;
2501
2502    let row_range = if range.end.column() == 0 {
2503        cmp::max(range.start.row(), start_row)..cmp::min(range.end.row(), end_row)
2504    } else {
2505        cmp::max(range.start.row(), start_row)..cmp::min(range.end.row() + 1, end_row)
2506    };
2507
2508    let first_y =
2509        content_origin.y() + row_range.start as f32 * position_map.line_height - scroll_top;
2510
2511    for (idx, row) in row_range.enumerate() {
2512        let line_layout = &position_map.line_layouts[(row - start_row) as usize];
2513
2514        let start_x = if row == range.start.row() {
2515            content_origin.x() + line_layout.x_for_index(range.start.column() as usize)
2516                - scroll_left
2517        } else {
2518            content_origin.x() - scroll_left
2519        };
2520
2521        let end_x = if row == range.end.row() {
2522            content_origin.x() + line_layout.x_for_index(range.end.column() as usize) - scroll_left
2523        } else {
2524            content_origin.x() + line_layout.width() + line_end_overshoot - scroll_left
2525        };
2526
2527        bounds.push(RectF::from_points(
2528            vec2f(start_x, first_y + position_map.line_height * idx as f32),
2529            vec2f(end_x, first_y + position_map.line_height * (idx + 1) as f32),
2530        ))
2531    }
2532
2533    bounds.into_iter()
2534}
2535
2536pub fn scale_vertical_mouse_autoscroll_delta(delta: f32) -> f32 {
2537    delta.powf(1.5) / 100.0
2538}
2539
2540fn scale_horizontal_mouse_autoscroll_delta(delta: f32) -> f32 {
2541    delta.powf(1.2) / 300.0
2542}
2543
2544#[cfg(test)]
2545mod tests {
2546    use std::sync::Arc;
2547
2548    use super::*;
2549    use crate::{
2550        display_map::{BlockDisposition, BlockProperties},
2551        Editor, MultiBuffer,
2552    };
2553    use settings::Settings;
2554    use util::test::sample_text;
2555
2556    #[gpui::test]
2557    fn test_layout_line_numbers(cx: &mut gpui::AppContext) {
2558        cx.set_global(Settings::test(cx));
2559        let buffer = MultiBuffer::build_simple(&sample_text(6, 6, 'a'), cx);
2560        let (window_id, editor) = cx.add_window(Default::default(), |cx| {
2561            Editor::new(EditorMode::Full, buffer, None, None, cx)
2562        });
2563        let element = EditorElement::new(editor.downgrade(), editor.read(cx).style(cx));
2564
2565        let layouts = editor.update(cx, |editor, cx| {
2566            let snapshot = editor.snapshot(cx);
2567            let mut presenter = cx.build_window(window_id, 30., Default::default());
2568            let layout_cx = presenter.build_layout_context(Vector2F::zero(), false, cx);
2569            element
2570                .layout_line_numbers(0..6, &Default::default(), false, &snapshot, &layout_cx)
2571                .0
2572        });
2573        assert_eq!(layouts.len(), 6);
2574    }
2575
2576    #[gpui::test]
2577    fn test_layout_with_placeholder_text_and_blocks(cx: &mut gpui::AppContext) {
2578        cx.set_global(Settings::test(cx));
2579        let buffer = MultiBuffer::build_simple("", cx);
2580        let (window_id, editor) = cx.add_window(Default::default(), |cx| {
2581            Editor::new(EditorMode::Full, buffer, None, None, cx)
2582        });
2583
2584        editor.update(cx, |editor, cx| {
2585            editor.set_placeholder_text("hello", cx);
2586            editor.insert_blocks(
2587                [BlockProperties {
2588                    style: BlockStyle::Fixed,
2589                    disposition: BlockDisposition::Above,
2590                    height: 3,
2591                    position: Anchor::min(),
2592                    render: Arc::new(|_| Empty::new().boxed()),
2593                }],
2594                cx,
2595            );
2596
2597            // Blur the editor so that it displays placeholder text.
2598            cx.blur();
2599        });
2600
2601        let mut element = EditorElement::new(editor.downgrade(), editor.read(cx).style(cx));
2602
2603        let mut scene = SceneBuilder::new(1.0);
2604        let mut presenter = cx.build_window(window_id, 30., Default::default());
2605        let mut layout_cx = presenter.build_layout_context(Vector2F::zero(), false, cx);
2606        let (size, mut state) = element.layout(
2607            SizeConstraint::new(vec2f(500., 500.), vec2f(500., 500.)),
2608            &mut layout_cx,
2609        );
2610
2611        assert_eq!(state.position_map.line_layouts.len(), 4);
2612        assert_eq!(
2613            state
2614                .line_number_layouts
2615                .iter()
2616                .map(Option::is_some)
2617                .collect::<Vec<_>>(),
2618            &[false, false, false, true]
2619        );
2620
2621        // Don't panic.
2622        let bounds = RectF::new(Default::default(), size);
2623        let mut paint_cx = presenter.build_paint_context(&mut scene, bounds.size(), cx);
2624        element.paint(bounds, bounds, &mut state, &mut paint_cx);
2625    }
2626}