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