element.rs

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