markdown.rs

   1pub mod html;
   2mod mermaid;
   3pub mod parser;
   4mod path_range;
   5
   6use base64::Engine as _;
   7use futures::FutureExt as _;
   8use gpui::EdgesRefinement;
   9use gpui::HitboxBehavior;
  10use gpui::UnderlineStyle;
  11use language::LanguageName;
  12
  13use log::Level;
  14use mermaid::{
  15    MermaidState, ParsedMarkdownMermaidDiagram, extract_mermaid_diagrams, render_mermaid_diagram,
  16};
  17pub use path_range::{LineCol, PathWithRange};
  18use settings::Settings as _;
  19use theme_settings::ThemeSettings;
  20use ui::Checkbox;
  21use ui::CopyButton;
  22
  23use std::borrow::Cow;
  24use std::collections::BTreeMap;
  25use std::iter;
  26use std::mem;
  27use std::ops::Range;
  28use std::path::Path;
  29use std::rc::Rc;
  30use std::sync::Arc;
  31use std::time::Duration;
  32
  33use collections::{HashMap, HashSet};
  34use gpui::{
  35    AnyElement, App, BorderStyle, Bounds, ClipboardItem, CursorStyle, DispatchPhase, Edges, Entity,
  36    FocusHandle, Focusable, FontStyle, FontWeight, GlobalElementId, Hitbox, Hsla, Image,
  37    ImageFormat, ImageSource, KeyContext, Length, MouseButton, MouseDownEvent, MouseEvent,
  38    MouseMoveEvent, MouseUpEvent, Point, ScrollHandle, Stateful, StrikethroughStyle,
  39    StyleRefinement, StyledText, Task, TextAlign, TextLayout, TextRun, TextStyle,
  40    TextStyleRefinement, actions, img, point, quad,
  41};
  42use language::{CharClassifier, Language, LanguageRegistry, Rope};
  43use parser::CodeBlockMetadata;
  44use parser::{
  45    MarkdownEvent, MarkdownTag, MarkdownTagEnd, parse_links_only, parse_markdown_with_options,
  46};
  47use pulldown_cmark::Alignment;
  48use sum_tree::TreeMap;
  49use theme::SyntaxTheme;
  50use ui::{ScrollAxes, Scrollbars, WithScrollbar, prelude::*};
  51use util::ResultExt;
  52
  53use crate::parser::CodeBlockKind;
  54
  55/// A callback function that can be used to customize the style of links based on the destination URL.
  56/// If the callback returns `None`, the default link style will be used.
  57type LinkStyleCallback = Rc<dyn Fn(&str, &App) -> Option<TextStyleRefinement>>;
  58type SourceClickCallback = Box<dyn Fn(usize, usize, &mut Window, &mut App) -> bool>;
  59type CheckboxToggleCallback = Rc<dyn Fn(Range<usize>, bool, &mut Window, &mut App)>;
  60/// Defines custom style refinements for each heading level (H1-H6)
  61#[derive(Clone, Default)]
  62pub struct HeadingLevelStyles {
  63    pub h1: Option<TextStyleRefinement>,
  64    pub h2: Option<TextStyleRefinement>,
  65    pub h3: Option<TextStyleRefinement>,
  66    pub h4: Option<TextStyleRefinement>,
  67    pub h5: Option<TextStyleRefinement>,
  68    pub h6: Option<TextStyleRefinement>,
  69}
  70
  71#[derive(Clone)]
  72pub struct MarkdownStyle {
  73    pub base_text_style: TextStyle,
  74    pub container_style: StyleRefinement,
  75    pub code_block: StyleRefinement,
  76    pub code_block_overflow_x_scroll: bool,
  77    pub inline_code: TextStyleRefinement,
  78    pub block_quote: TextStyleRefinement,
  79    pub link: TextStyleRefinement,
  80    pub link_callback: Option<LinkStyleCallback>,
  81    pub rule_color: Hsla,
  82    pub block_quote_border_color: Hsla,
  83    pub syntax: Arc<SyntaxTheme>,
  84    pub selection_background_color: Hsla,
  85    pub heading: StyleRefinement,
  86    pub heading_level_styles: Option<HeadingLevelStyles>,
  87    pub height_is_multiple_of_line_height: bool,
  88    pub prevent_mouse_interaction: bool,
  89    pub table_columns_min_size: bool,
  90}
  91
  92impl Default for MarkdownStyle {
  93    fn default() -> Self {
  94        Self {
  95            base_text_style: Default::default(),
  96            container_style: Default::default(),
  97            code_block: Default::default(),
  98            code_block_overflow_x_scroll: false,
  99            inline_code: Default::default(),
 100            block_quote: Default::default(),
 101            link: Default::default(),
 102            link_callback: None,
 103            rule_color: Default::default(),
 104            block_quote_border_color: Default::default(),
 105            syntax: Arc::new(SyntaxTheme::default()),
 106            selection_background_color: Default::default(),
 107            heading: Default::default(),
 108            heading_level_styles: None,
 109            height_is_multiple_of_line_height: false,
 110            prevent_mouse_interaction: false,
 111            table_columns_min_size: false,
 112        }
 113    }
 114}
 115
 116pub enum MarkdownFont {
 117    Agent,
 118    Editor,
 119}
 120
 121impl MarkdownStyle {
 122    pub fn themed(font: MarkdownFont, window: &Window, cx: &App) -> Self {
 123        let theme_settings = ThemeSettings::get_global(cx);
 124        let colors = cx.theme().colors();
 125
 126        let buffer_font_weight = theme_settings.buffer_font.weight;
 127        let (buffer_font_size, ui_font_size) = match font {
 128            MarkdownFont::Agent => (
 129                theme_settings.agent_buffer_font_size(cx),
 130                theme_settings.agent_ui_font_size(cx),
 131            ),
 132            MarkdownFont::Editor => (
 133                theme_settings.buffer_font_size(cx),
 134                theme_settings.ui_font_size(cx),
 135            ),
 136        };
 137
 138        let text_color = colors.text;
 139
 140        let mut text_style = window.text_style();
 141        let line_height = buffer_font_size * 1.75;
 142
 143        text_style.refine(&TextStyleRefinement {
 144            font_family: Some(theme_settings.ui_font.family.clone()),
 145            font_fallbacks: theme_settings.ui_font.fallbacks.clone(),
 146            font_features: Some(theme_settings.ui_font.features.clone()),
 147            font_size: Some(ui_font_size.into()),
 148            line_height: Some(line_height.into()),
 149            color: Some(text_color),
 150            ..Default::default()
 151        });
 152
 153        MarkdownStyle {
 154            base_text_style: text_style.clone(),
 155            syntax: cx.theme().syntax().clone(),
 156            selection_background_color: colors.element_selection_background,
 157            rule_color: colors.border,
 158            block_quote_border_color: colors.border,
 159            code_block_overflow_x_scroll: true,
 160            heading_level_styles: Some(HeadingLevelStyles {
 161                h1: Some(TextStyleRefinement {
 162                    font_size: Some(rems(1.15).into()),
 163                    ..Default::default()
 164                }),
 165                h2: Some(TextStyleRefinement {
 166                    font_size: Some(rems(1.1).into()),
 167                    ..Default::default()
 168                }),
 169                h3: Some(TextStyleRefinement {
 170                    font_size: Some(rems(1.05).into()),
 171                    ..Default::default()
 172                }),
 173                h4: Some(TextStyleRefinement {
 174                    font_size: Some(rems(1.).into()),
 175                    ..Default::default()
 176                }),
 177                h5: Some(TextStyleRefinement {
 178                    font_size: Some(rems(0.95).into()),
 179                    ..Default::default()
 180                }),
 181                h6: Some(TextStyleRefinement {
 182                    font_size: Some(rems(0.875).into()),
 183                    ..Default::default()
 184                }),
 185            }),
 186            code_block: StyleRefinement {
 187                padding: EdgesRefinement {
 188                    top: Some(DefiniteLength::Absolute(AbsoluteLength::Pixels(px(8.)))),
 189                    left: Some(DefiniteLength::Absolute(AbsoluteLength::Pixels(px(8.)))),
 190                    right: Some(DefiniteLength::Absolute(AbsoluteLength::Pixels(px(8.)))),
 191                    bottom: Some(DefiniteLength::Absolute(AbsoluteLength::Pixels(px(8.)))),
 192                },
 193                margin: EdgesRefinement {
 194                    top: Some(Length::Definite(px(8.).into())),
 195                    left: Some(Length::Definite(px(0.).into())),
 196                    right: Some(Length::Definite(px(0.).into())),
 197                    bottom: Some(Length::Definite(px(12.).into())),
 198                },
 199                border_style: Some(BorderStyle::Solid),
 200                border_widths: EdgesRefinement {
 201                    top: Some(AbsoluteLength::Pixels(px(1.))),
 202                    left: Some(AbsoluteLength::Pixels(px(1.))),
 203                    right: Some(AbsoluteLength::Pixels(px(1.))),
 204                    bottom: Some(AbsoluteLength::Pixels(px(1.))),
 205                },
 206                border_color: Some(colors.border_variant),
 207                background: Some(colors.editor_background.into()),
 208                text: TextStyleRefinement {
 209                    font_family: Some(theme_settings.buffer_font.family.clone()),
 210                    font_fallbacks: theme_settings.buffer_font.fallbacks.clone(),
 211                    font_features: Some(theme_settings.buffer_font.features.clone()),
 212                    font_size: Some(buffer_font_size.into()),
 213                    font_weight: Some(buffer_font_weight),
 214                    ..Default::default()
 215                },
 216                ..Default::default()
 217            },
 218            inline_code: TextStyleRefinement {
 219                font_family: Some(theme_settings.buffer_font.family.clone()),
 220                font_fallbacks: theme_settings.buffer_font.fallbacks.clone(),
 221                font_features: Some(theme_settings.buffer_font.features.clone()),
 222                font_size: Some(buffer_font_size.into()),
 223                font_weight: Some(buffer_font_weight),
 224                background_color: Some(colors.editor_foreground.opacity(0.08)),
 225                ..Default::default()
 226            },
 227            link: TextStyleRefinement {
 228                background_color: Some(colors.editor_foreground.opacity(0.025)),
 229                color: Some(colors.text_accent),
 230                underline: Some(UnderlineStyle {
 231                    color: Some(colors.text_accent.opacity(0.5)),
 232                    thickness: px(1.),
 233                    ..Default::default()
 234                }),
 235                ..Default::default()
 236            },
 237            ..Default::default()
 238        }
 239    }
 240
 241    pub fn with_muted_text(mut self, cx: &App) -> Self {
 242        let colors = cx.theme().colors();
 243        self.base_text_style.color = colors.text_muted;
 244        self
 245    }
 246}
 247
 248pub struct Markdown {
 249    source: SharedString,
 250    selection: Selection,
 251    pressed_link: Option<RenderedLink>,
 252    autoscroll_request: Option<usize>,
 253    active_root_block: Option<usize>,
 254    parsed_markdown: ParsedMarkdown,
 255    images_by_source_offset: HashMap<usize, Arc<Image>>,
 256    should_reparse: bool,
 257    pending_parse: Option<Task<()>>,
 258    focus_handle: FocusHandle,
 259    language_registry: Option<Arc<LanguageRegistry>>,
 260    fallback_code_block_language: Option<LanguageName>,
 261    options: MarkdownOptions,
 262    mermaid_state: MermaidState,
 263    copied_code_blocks: HashSet<ElementId>,
 264    code_block_scroll_handles: BTreeMap<usize, ScrollHandle>,
 265    context_menu_selected_text: Option<String>,
 266    search_highlights: Vec<Range<usize>>,
 267    active_search_highlight: Option<usize>,
 268}
 269
 270#[derive(Clone, Copy, Default)]
 271pub struct MarkdownOptions {
 272    pub parse_links_only: bool,
 273    pub parse_html: bool,
 274    pub render_mermaid_diagrams: bool,
 275}
 276
 277#[derive(Clone, Copy, PartialEq, Eq)]
 278pub enum CopyButtonVisibility {
 279    Hidden,
 280    AlwaysVisible,
 281    VisibleOnHover,
 282}
 283
 284pub enum CodeBlockRenderer {
 285    Default {
 286        copy_button_visibility: CopyButtonVisibility,
 287        border: bool,
 288    },
 289    Custom {
 290        render: CodeBlockRenderFn,
 291        /// A function that can modify the parent container after the code block
 292        /// content has been appended as a child element.
 293        transform: Option<CodeBlockTransformFn>,
 294    },
 295}
 296
 297pub type CodeBlockRenderFn = Arc<
 298    dyn Fn(
 299        &CodeBlockKind,
 300        &ParsedMarkdown,
 301        Range<usize>,
 302        CodeBlockMetadata,
 303        &mut Window,
 304        &App,
 305    ) -> Div,
 306>;
 307
 308pub type CodeBlockTransformFn =
 309    Arc<dyn Fn(AnyDiv, Range<usize>, CodeBlockMetadata, &mut Window, &App) -> AnyDiv>;
 310
 311actions!(
 312    markdown,
 313    [
 314        /// Copies the selected text to the clipboard.
 315        Copy,
 316        /// Copies the selected text as markdown to the clipboard.
 317        CopyAsMarkdown
 318    ]
 319);
 320
 321enum EscapeAction {
 322    PassThrough,
 323    Nbsp(usize),
 324    DoubleNewline,
 325    PrefixBackslash,
 326}
 327
 328impl EscapeAction {
 329    fn output_len(&self) -> usize {
 330        match self {
 331            Self::PassThrough => 1,
 332            Self::Nbsp(count) => count * '\u{00A0}'.len_utf8(),
 333            Self::DoubleNewline => 2,
 334            Self::PrefixBackslash => 2,
 335        }
 336    }
 337
 338    fn write_to(&self, c: char, output: &mut String) {
 339        match self {
 340            Self::PassThrough => output.push(c),
 341            Self::Nbsp(count) => {
 342                for _ in 0..*count {
 343                    output.push('\u{00A0}');
 344                }
 345            }
 346            Self::DoubleNewline => {
 347                output.push('\n');
 348                output.push('\n');
 349            }
 350            Self::PrefixBackslash => {
 351                // '\\' is a single backslash in Rust, e.g. '|' -> '\|'
 352                output.push('\\');
 353                output.push(c);
 354            }
 355        }
 356    }
 357}
 358
 359// Valid to operate on raw bytes since multi-byte UTF-8
 360// sequences never contain ASCII-range bytes.
 361struct MarkdownEscaper {
 362    in_leading_whitespace: bool,
 363}
 364
 365impl MarkdownEscaper {
 366    const TAB_SIZE: usize = 4;
 367
 368    fn new() -> Self {
 369        Self {
 370            in_leading_whitespace: true,
 371        }
 372    }
 373
 374    fn next(&mut self, byte: u8) -> EscapeAction {
 375        let action = if self.in_leading_whitespace && byte == b'\t' {
 376            EscapeAction::Nbsp(Self::TAB_SIZE)
 377        } else if self.in_leading_whitespace && byte == b' ' {
 378            EscapeAction::Nbsp(1)
 379        } else if byte == b'\n' {
 380            EscapeAction::DoubleNewline
 381        } else if byte.is_ascii_punctuation() {
 382            EscapeAction::PrefixBackslash
 383        } else {
 384            EscapeAction::PassThrough
 385        };
 386
 387        self.in_leading_whitespace =
 388            byte == b'\n' || (self.in_leading_whitespace && (byte == b' ' || byte == b'\t'));
 389        action
 390    }
 391}
 392
 393impl Markdown {
 394    pub fn new(
 395        source: SharedString,
 396        language_registry: Option<Arc<LanguageRegistry>>,
 397        fallback_code_block_language: Option<LanguageName>,
 398        cx: &mut Context<Self>,
 399    ) -> Self {
 400        Self::new_with_options(
 401            source,
 402            language_registry,
 403            fallback_code_block_language,
 404            MarkdownOptions::default(),
 405            cx,
 406        )
 407    }
 408
 409    pub fn new_with_options(
 410        source: SharedString,
 411        language_registry: Option<Arc<LanguageRegistry>>,
 412        fallback_code_block_language: Option<LanguageName>,
 413        options: MarkdownOptions,
 414        cx: &mut Context<Self>,
 415    ) -> Self {
 416        let focus_handle = cx.focus_handle();
 417        let mut this = Self {
 418            source,
 419            selection: Selection::default(),
 420            pressed_link: None,
 421            autoscroll_request: None,
 422            active_root_block: None,
 423            should_reparse: false,
 424            images_by_source_offset: Default::default(),
 425            parsed_markdown: ParsedMarkdown::default(),
 426            pending_parse: None,
 427            focus_handle,
 428            language_registry,
 429            fallback_code_block_language,
 430            options,
 431            mermaid_state: MermaidState::default(),
 432            copied_code_blocks: HashSet::default(),
 433            code_block_scroll_handles: BTreeMap::default(),
 434            context_menu_selected_text: None,
 435            search_highlights: Vec::new(),
 436            active_search_highlight: None,
 437        };
 438        this.parse(cx);
 439        this
 440    }
 441
 442    pub fn new_text(source: SharedString, cx: &mut Context<Self>) -> Self {
 443        Self::new_with_options(
 444            source,
 445            None,
 446            None,
 447            MarkdownOptions {
 448                parse_links_only: true,
 449                ..Default::default()
 450            },
 451            cx,
 452        )
 453    }
 454
 455    fn code_block_scroll_handle(&mut self, id: usize) -> ScrollHandle {
 456        self.code_block_scroll_handles
 457            .entry(id)
 458            .or_insert_with(ScrollHandle::new)
 459            .clone()
 460    }
 461
 462    fn retain_code_block_scroll_handles(&mut self, ids: &HashSet<usize>) {
 463        self.code_block_scroll_handles
 464            .retain(|id, _| ids.contains(id));
 465    }
 466
 467    fn clear_code_block_scroll_handles(&mut self) {
 468        self.code_block_scroll_handles.clear();
 469    }
 470
 471    fn autoscroll_code_block(&self, source_index: usize, cursor_position: Point<Pixels>) {
 472        let Some((_, scroll_handle)) = self
 473            .code_block_scroll_handles
 474            .range(..=source_index)
 475            .next_back()
 476        else {
 477            return;
 478        };
 479
 480        let bounds = scroll_handle.bounds();
 481        if cursor_position.y < bounds.top() || cursor_position.y > bounds.bottom() {
 482            return;
 483        }
 484
 485        let horizontal_delta = if cursor_position.x < bounds.left() {
 486            bounds.left() - cursor_position.x
 487        } else if cursor_position.x > bounds.right() {
 488            bounds.right() - cursor_position.x
 489        } else {
 490            return;
 491        };
 492
 493        let offset = scroll_handle.offset();
 494        scroll_handle.set_offset(point(offset.x + horizontal_delta, offset.y));
 495    }
 496
 497    pub fn is_parsing(&self) -> bool {
 498        self.pending_parse.is_some()
 499    }
 500
 501    pub fn source(&self) -> &str {
 502        &self.source
 503    }
 504
 505    pub fn append(&mut self, text: &str, cx: &mut Context<Self>) {
 506        self.source = SharedString::new(self.source.to_string() + text);
 507        self.parse(cx);
 508    }
 509
 510    pub fn replace(&mut self, source: impl Into<SharedString>, cx: &mut Context<Self>) {
 511        self.source = source.into();
 512        self.parse(cx);
 513    }
 514
 515    pub fn request_autoscroll_to_source_index(
 516        &mut self,
 517        source_index: usize,
 518        cx: &mut Context<Self>,
 519    ) {
 520        self.autoscroll_request = Some(source_index);
 521        cx.refresh_windows();
 522    }
 523
 524    pub fn set_active_root_for_source_index(
 525        &mut self,
 526        source_index: Option<usize>,
 527        cx: &mut Context<Self>,
 528    ) {
 529        let active_root_block =
 530            source_index.and_then(|index| self.parsed_markdown.root_block_for_source_index(index));
 531        if self.active_root_block == active_root_block {
 532            return;
 533        }
 534
 535        self.active_root_block = active_root_block;
 536        cx.notify();
 537    }
 538
 539    pub fn reset(&mut self, source: SharedString, cx: &mut Context<Self>) {
 540        if source == self.source() {
 541            return;
 542        }
 543        self.source = source;
 544        self.selection = Selection::default();
 545        self.autoscroll_request = None;
 546        self.pending_parse = None;
 547        self.should_reparse = false;
 548        self.search_highlights.clear();
 549        self.active_search_highlight = None;
 550        // Don't clear parsed_markdown here - keep existing content visible until new parse completes
 551        self.parse(cx);
 552    }
 553
 554    #[cfg(any(test, feature = "test-support"))]
 555    pub fn parsed_markdown(&self) -> &ParsedMarkdown {
 556        &self.parsed_markdown
 557    }
 558
 559    pub fn escape(s: &str) -> Cow<'_, str> {
 560        let output_len: usize = {
 561            let mut escaper = MarkdownEscaper::new();
 562            s.bytes().map(|byte| escaper.next(byte).output_len()).sum()
 563        };
 564
 565        if output_len == s.len() {
 566            return s.into();
 567        }
 568
 569        let mut escaper = MarkdownEscaper::new();
 570        let mut output = String::with_capacity(output_len);
 571        for c in s.chars() {
 572            escaper.next(c as u8).write_to(c, &mut output);
 573        }
 574        output.into()
 575    }
 576
 577    pub fn selected_text(&self) -> Option<String> {
 578        if self.selection.end <= self.selection.start {
 579            None
 580        } else {
 581            Some(self.source[self.selection.start..self.selection.end].to_string())
 582        }
 583    }
 584
 585    pub fn set_search_highlights(
 586        &mut self,
 587        highlights: Vec<Range<usize>>,
 588        active: Option<usize>,
 589        cx: &mut Context<Self>,
 590    ) {
 591        self.search_highlights = highlights;
 592        self.active_search_highlight = active;
 593        cx.notify();
 594    }
 595
 596    pub fn clear_search_highlights(&mut self, cx: &mut Context<Self>) {
 597        if !self.search_highlights.is_empty() || self.active_search_highlight.is_some() {
 598            self.search_highlights.clear();
 599            self.active_search_highlight = None;
 600            cx.notify();
 601        }
 602    }
 603
 604    pub fn set_active_search_highlight(&mut self, active: Option<usize>, cx: &mut Context<Self>) {
 605        if self.active_search_highlight != active {
 606            self.active_search_highlight = active;
 607            cx.notify();
 608        }
 609    }
 610
 611    pub fn search_highlights(&self) -> &[Range<usize>] {
 612        &self.search_highlights
 613    }
 614
 615    pub fn active_search_highlight(&self) -> Option<usize> {
 616        self.active_search_highlight
 617    }
 618
 619    fn copy(&self, text: &RenderedText, _: &mut Window, cx: &mut Context<Self>) {
 620        if self.selection.end <= self.selection.start {
 621            return;
 622        }
 623        let text = text.text_for_range(self.selection.start..self.selection.end);
 624        cx.write_to_clipboard(ClipboardItem::new_string(text));
 625    }
 626
 627    fn copy_as_markdown(&mut self, _: &mut Window, cx: &mut Context<Self>) {
 628        if let Some(text) = self.context_menu_selected_text.take() {
 629            cx.write_to_clipboard(ClipboardItem::new_string(text));
 630            return;
 631        }
 632        if self.selection.end <= self.selection.start {
 633            return;
 634        }
 635        let text = self.source[self.selection.start..self.selection.end].to_string();
 636        cx.write_to_clipboard(ClipboardItem::new_string(text));
 637    }
 638
 639    fn capture_selection_for_context_menu(&mut self) {
 640        self.context_menu_selected_text = self.selected_text();
 641    }
 642
 643    fn parse(&mut self, cx: &mut Context<Self>) {
 644        if self.source.is_empty() {
 645            self.should_reparse = false;
 646            self.pending_parse.take();
 647            self.parsed_markdown = ParsedMarkdown {
 648                source: self.source.clone(),
 649                ..Default::default()
 650            };
 651            self.active_root_block = None;
 652            self.images_by_source_offset.clear();
 653            self.mermaid_state.clear();
 654            cx.notify();
 655            cx.refresh_windows();
 656            return;
 657        }
 658
 659        if self.pending_parse.is_some() {
 660            self.should_reparse = true;
 661            return;
 662        }
 663        self.should_reparse = false;
 664        self.pending_parse = Some(self.start_background_parse(cx));
 665    }
 666
 667    fn start_background_parse(&self, cx: &Context<Self>) -> Task<()> {
 668        let source = self.source.clone();
 669        let should_parse_links_only = self.options.parse_links_only;
 670        let should_parse_html = self.options.parse_html;
 671        let should_render_mermaid_diagrams = self.options.render_mermaid_diagrams;
 672        let language_registry = self.language_registry.clone();
 673        let fallback = self.fallback_code_block_language.clone();
 674
 675        let parsed = cx.background_spawn(async move {
 676            if should_parse_links_only {
 677                return (
 678                    ParsedMarkdown {
 679                        events: Arc::from(parse_links_only(source.as_ref())),
 680                        source,
 681                        languages_by_name: TreeMap::default(),
 682                        languages_by_path: TreeMap::default(),
 683                        root_block_starts: Arc::default(),
 684                        html_blocks: BTreeMap::default(),
 685                        mermaid_diagrams: BTreeMap::default(),
 686                    },
 687                    Default::default(),
 688                );
 689            }
 690
 691            let parsed = parse_markdown_with_options(&source, should_parse_html);
 692            let events = parsed.events;
 693            let language_names = parsed.language_names;
 694            let paths = parsed.language_paths;
 695            let root_block_starts = parsed.root_block_starts;
 696            let html_blocks = parsed.html_blocks;
 697            let mermaid_diagrams = if should_render_mermaid_diagrams {
 698                extract_mermaid_diagrams(&source, &events)
 699            } else {
 700                BTreeMap::default()
 701            };
 702            let mut images_by_source_offset = HashMap::default();
 703            let mut languages_by_name = TreeMap::default();
 704            let mut languages_by_path = TreeMap::default();
 705            if let Some(registry) = language_registry.as_ref() {
 706                for name in language_names {
 707                    let language = if !name.is_empty() {
 708                        registry.language_for_name_or_extension(&name).left_future()
 709                    } else if let Some(fallback) = &fallback {
 710                        registry.language_for_name(fallback.as_ref()).right_future()
 711                    } else {
 712                        continue;
 713                    };
 714                    if let Ok(language) = language.await {
 715                        languages_by_name.insert(name, language);
 716                    }
 717                }
 718
 719                for path in paths {
 720                    if let Ok(language) = registry
 721                        .load_language_for_file_path(Path::new(path.as_ref()))
 722                        .await
 723                    {
 724                        languages_by_path.insert(path, language);
 725                    }
 726                }
 727            }
 728
 729            for (range, event) in &events {
 730                if let MarkdownEvent::Start(MarkdownTag::Image { dest_url, .. }) = event
 731                    && let Some(data_url) = dest_url.strip_prefix("data:")
 732                {
 733                    let Some((mime_info, data)) = data_url.split_once(',') else {
 734                        continue;
 735                    };
 736                    let Some((mime_type, encoding)) = mime_info.split_once(';') else {
 737                        continue;
 738                    };
 739                    let Some(format) = ImageFormat::from_mime_type(mime_type) else {
 740                        continue;
 741                    };
 742                    let is_base64 = encoding == "base64";
 743                    if is_base64
 744                        && let Some(bytes) = base64::prelude::BASE64_STANDARD
 745                            .decode(data)
 746                            .log_with_level(Level::Debug)
 747                    {
 748                        let image = Arc::new(Image::from_bytes(format, bytes));
 749                        images_by_source_offset.insert(range.start, image);
 750                    }
 751                }
 752            }
 753
 754            (
 755                ParsedMarkdown {
 756                    source,
 757                    events: Arc::from(events),
 758                    languages_by_name,
 759                    languages_by_path,
 760                    root_block_starts: Arc::from(root_block_starts),
 761                    html_blocks,
 762                    mermaid_diagrams,
 763                },
 764                images_by_source_offset,
 765            )
 766        });
 767
 768        cx.spawn(async move |this, cx| {
 769            let (parsed, images_by_source_offset) = parsed.await;
 770
 771            this.update(cx, |this, cx| {
 772                this.parsed_markdown = parsed;
 773                this.images_by_source_offset = images_by_source_offset;
 774                if this.active_root_block.is_some_and(|block_index| {
 775                    block_index >= this.parsed_markdown.root_block_starts.len()
 776                }) {
 777                    this.active_root_block = None;
 778                }
 779                if this.options.render_mermaid_diagrams {
 780                    let parsed_markdown = this.parsed_markdown.clone();
 781                    this.mermaid_state.update(&parsed_markdown, cx);
 782                } else {
 783                    this.mermaid_state.clear();
 784                }
 785                this.pending_parse.take();
 786                if this.should_reparse {
 787                    this.parse(cx);
 788                }
 789                cx.notify();
 790                cx.refresh_windows();
 791            })
 792            .ok();
 793        })
 794    }
 795}
 796
 797impl Focusable for Markdown {
 798    fn focus_handle(&self, _cx: &App) -> FocusHandle {
 799        self.focus_handle.clone()
 800    }
 801}
 802
 803#[derive(Debug, Default, Clone)]
 804enum SelectMode {
 805    #[default]
 806    Character,
 807    Word(Range<usize>),
 808    Line(Range<usize>),
 809    All,
 810}
 811
 812#[derive(Clone, Default)]
 813struct Selection {
 814    start: usize,
 815    end: usize,
 816    reversed: bool,
 817    pending: bool,
 818    mode: SelectMode,
 819}
 820
 821impl Selection {
 822    fn set_head(&mut self, head: usize, rendered_text: &RenderedText) {
 823        match &self.mode {
 824            SelectMode::Character => {
 825                if head < self.tail() {
 826                    if !self.reversed {
 827                        self.end = self.start;
 828                        self.reversed = true;
 829                    }
 830                    self.start = head;
 831                } else {
 832                    if self.reversed {
 833                        self.start = self.end;
 834                        self.reversed = false;
 835                    }
 836                    self.end = head;
 837                }
 838            }
 839            SelectMode::Word(original_range) | SelectMode::Line(original_range) => {
 840                let head_range = if matches!(self.mode, SelectMode::Word(_)) {
 841                    rendered_text.surrounding_word_range(head)
 842                } else {
 843                    rendered_text.surrounding_line_range(head)
 844                };
 845
 846                if head < original_range.start {
 847                    self.start = head_range.start;
 848                    self.end = original_range.end;
 849                    self.reversed = true;
 850                } else if head >= original_range.end {
 851                    self.start = original_range.start;
 852                    self.end = head_range.end;
 853                    self.reversed = false;
 854                } else {
 855                    self.start = original_range.start;
 856                    self.end = original_range.end;
 857                    self.reversed = false;
 858                }
 859            }
 860            SelectMode::All => {
 861                self.start = 0;
 862                self.end = rendered_text
 863                    .lines
 864                    .last()
 865                    .map(|line| line.source_end)
 866                    .unwrap_or(0);
 867                self.reversed = false;
 868            }
 869        }
 870    }
 871
 872    fn tail(&self) -> usize {
 873        if self.reversed { self.end } else { self.start }
 874    }
 875}
 876
 877#[derive(Debug, Clone, Default)]
 878pub struct ParsedMarkdown {
 879    pub source: SharedString,
 880    pub events: Arc<[(Range<usize>, MarkdownEvent)]>,
 881    pub languages_by_name: TreeMap<SharedString, Arc<Language>>,
 882    pub languages_by_path: TreeMap<Arc<str>, Arc<Language>>,
 883    pub root_block_starts: Arc<[usize]>,
 884    pub(crate) html_blocks: BTreeMap<usize, html::html_parser::ParsedHtmlBlock>,
 885    pub(crate) mermaid_diagrams: BTreeMap<usize, ParsedMarkdownMermaidDiagram>,
 886}
 887
 888impl ParsedMarkdown {
 889    pub fn source(&self) -> &SharedString {
 890        &self.source
 891    }
 892
 893    pub fn events(&self) -> &Arc<[(Range<usize>, MarkdownEvent)]> {
 894        &self.events
 895    }
 896
 897    pub fn root_block_starts(&self) -> &Arc<[usize]> {
 898        &self.root_block_starts
 899    }
 900
 901    pub fn root_block_for_source_index(&self, source_index: usize) -> Option<usize> {
 902        if self.root_block_starts.is_empty() {
 903            return None;
 904        }
 905
 906        let partition = self
 907            .root_block_starts
 908            .partition_point(|block_start| *block_start <= source_index);
 909
 910        Some(partition.saturating_sub(1))
 911    }
 912}
 913
 914pub enum AutoscrollBehavior {
 915    /// Propagate the request up the element tree for the nearest
 916    /// scrollable ancestor (e.g. `List`) to handle.
 917    Propagate,
 918    /// Directly control a specific scroll handle.
 919    Controlled(ScrollHandle),
 920}
 921
 922pub struct MarkdownElement {
 923    markdown: Entity<Markdown>,
 924    style: MarkdownStyle,
 925    code_block_renderer: CodeBlockRenderer,
 926    on_url_click: Option<Box<dyn Fn(SharedString, &mut Window, &mut App)>>,
 927    on_source_click: Option<SourceClickCallback>,
 928    on_checkbox_toggle: Option<CheckboxToggleCallback>,
 929    image_resolver: Option<Box<dyn Fn(&str) -> Option<ImageSource>>>,
 930    show_root_block_markers: bool,
 931    autoscroll: AutoscrollBehavior,
 932}
 933
 934impl MarkdownElement {
 935    pub fn new(markdown: Entity<Markdown>, style: MarkdownStyle) -> Self {
 936        Self {
 937            markdown,
 938            style,
 939            code_block_renderer: CodeBlockRenderer::Default {
 940                copy_button_visibility: CopyButtonVisibility::VisibleOnHover,
 941                border: false,
 942            },
 943            on_url_click: None,
 944            on_source_click: None,
 945            on_checkbox_toggle: None,
 946            image_resolver: None,
 947            show_root_block_markers: false,
 948            autoscroll: AutoscrollBehavior::Propagate,
 949        }
 950    }
 951
 952    #[cfg(any(test, feature = "test-support"))]
 953    pub fn rendered_text(
 954        markdown: Entity<Markdown>,
 955        cx: &mut gpui::VisualTestContext,
 956        style: impl FnOnce(&Window, &App) -> MarkdownStyle,
 957    ) -> String {
 958        use gpui::size;
 959
 960        let (text, _) = cx.draw(
 961            Default::default(),
 962            size(px(600.0), px(600.0)),
 963            |window, cx| Self::new(markdown, style(window, cx)),
 964        );
 965        text.text
 966            .lines
 967            .iter()
 968            .map(|line| line.layout.wrapped_text())
 969            .collect::<Vec<_>>()
 970            .join("\n")
 971    }
 972
 973    pub fn code_block_renderer(mut self, variant: CodeBlockRenderer) -> Self {
 974        self.code_block_renderer = variant;
 975        self
 976    }
 977
 978    pub fn on_url_click(
 979        mut self,
 980        handler: impl Fn(SharedString, &mut Window, &mut App) + 'static,
 981    ) -> Self {
 982        self.on_url_click = Some(Box::new(handler));
 983        self
 984    }
 985
 986    pub fn on_source_click(
 987        mut self,
 988        handler: impl Fn(usize, usize, &mut Window, &mut App) -> bool + 'static,
 989    ) -> Self {
 990        self.on_source_click = Some(Box::new(handler));
 991        self
 992    }
 993
 994    pub fn on_checkbox_toggle(
 995        mut self,
 996        handler: impl Fn(Range<usize>, bool, &mut Window, &mut App) + 'static,
 997    ) -> Self {
 998        self.on_checkbox_toggle = Some(Rc::new(handler));
 999        self
1000    }
1001
1002    pub fn image_resolver(
1003        mut self,
1004        resolver: impl Fn(&str) -> Option<ImageSource> + 'static,
1005    ) -> Self {
1006        self.image_resolver = Some(Box::new(resolver));
1007        self
1008    }
1009
1010    pub fn show_root_block_markers(mut self) -> Self {
1011        self.show_root_block_markers = true;
1012        self
1013    }
1014
1015    pub fn scroll_handle(mut self, scroll_handle: ScrollHandle) -> Self {
1016        self.autoscroll = AutoscrollBehavior::Controlled(scroll_handle);
1017        self
1018    }
1019
1020    fn push_markdown_image(
1021        &self,
1022        builder: &mut MarkdownElementBuilder,
1023        range: &Range<usize>,
1024        source: ImageSource,
1025        width: Option<DefiniteLength>,
1026        height: Option<DefiniteLength>,
1027    ) {
1028        let align = builder.text_style().text_align;
1029        builder.modify_current_div(|el| {
1030            let mut image_container = el.flex().flex_row().items_center();
1031
1032            image_container = match align {
1033                TextAlign::Left => image_container.justify_start(),
1034                TextAlign::Center => image_container.justify_center(),
1035                TextAlign::Right => image_container.justify_end(),
1036            };
1037
1038            image_container.child(
1039                img(source)
1040                    .max_w_full()
1041                    .when_some(height, |this, height| this.h(height))
1042                    .when_some(width, |this, width| this.w(width)),
1043            )
1044        });
1045        let _ = range;
1046    }
1047
1048    fn push_markdown_paragraph(
1049        &self,
1050        builder: &mut MarkdownElementBuilder,
1051        range: &Range<usize>,
1052        markdown_end: usize,
1053        text_align_override: Option<TextAlign>,
1054    ) {
1055        let align = text_align_override.unwrap_or(self.style.base_text_style.text_align);
1056        let mut paragraph = div().when(!self.style.height_is_multiple_of_line_height, |el| {
1057            el.mb_2().line_height(rems(1.3))
1058        });
1059
1060        paragraph = match align {
1061            TextAlign::Center => paragraph.text_center(),
1062            TextAlign::Left => paragraph.text_left(),
1063            TextAlign::Right => paragraph.text_right(),
1064        };
1065
1066        builder.push_text_style(TextStyleRefinement {
1067            text_align: Some(align),
1068            ..Default::default()
1069        });
1070        builder.push_div(paragraph, range, markdown_end);
1071    }
1072
1073    fn pop_markdown_paragraph(&self, builder: &mut MarkdownElementBuilder) {
1074        builder.pop_div();
1075        builder.pop_text_style();
1076    }
1077
1078    fn push_markdown_heading(
1079        &self,
1080        builder: &mut MarkdownElementBuilder,
1081        level: pulldown_cmark::HeadingLevel,
1082        range: &Range<usize>,
1083        markdown_end: usize,
1084        text_align_override: Option<TextAlign>,
1085    ) {
1086        let align = text_align_override.unwrap_or(self.style.base_text_style.text_align);
1087        let mut heading = div().mb_2();
1088        heading = apply_heading_style(heading, level, self.style.heading_level_styles.as_ref());
1089
1090        heading = match align {
1091            TextAlign::Center => heading.text_center(),
1092            TextAlign::Left => heading.text_left(),
1093            TextAlign::Right => heading.text_right(),
1094        };
1095
1096        let mut heading_style = self.style.heading.clone();
1097        let heading_text_style = heading_style.text_style().clone();
1098        heading.style().refine(&heading_style);
1099
1100        builder.push_text_style(TextStyleRefinement {
1101            text_align: Some(align),
1102            ..heading_text_style
1103        });
1104        builder.push_div(heading, range, markdown_end);
1105    }
1106
1107    fn pop_markdown_heading(&self, builder: &mut MarkdownElementBuilder) {
1108        builder.pop_div();
1109        builder.pop_text_style();
1110    }
1111
1112    fn push_markdown_block_quote(
1113        &self,
1114        builder: &mut MarkdownElementBuilder,
1115        range: &Range<usize>,
1116        markdown_end: usize,
1117    ) {
1118        builder.push_text_style(self.style.block_quote.clone());
1119        builder.push_div(
1120            div()
1121                .pl_4()
1122                .mb_2()
1123                .border_l_4()
1124                .border_color(self.style.block_quote_border_color),
1125            range,
1126            markdown_end,
1127        );
1128    }
1129
1130    fn pop_markdown_block_quote(&self, builder: &mut MarkdownElementBuilder) {
1131        builder.pop_div();
1132        builder.pop_text_style();
1133    }
1134
1135    fn push_markdown_list_item(
1136        &self,
1137        builder: &mut MarkdownElementBuilder,
1138        bullet: AnyElement,
1139        range: &Range<usize>,
1140        markdown_end: usize,
1141    ) {
1142        builder.push_div(
1143            div()
1144                .when(!self.style.height_is_multiple_of_line_height, |el| {
1145                    el.mb_1().gap_1().line_height(rems(1.3))
1146                })
1147                .h_flex()
1148                .items_start()
1149                .child(bullet),
1150            range,
1151            markdown_end,
1152        );
1153        // Without `w_0`, text doesn't wrap to the width of the container.
1154        builder.push_div(div().flex_1().w_0(), range, markdown_end);
1155    }
1156
1157    fn pop_markdown_list_item(&self, builder: &mut MarkdownElementBuilder) {
1158        builder.pop_div();
1159        builder.pop_div();
1160    }
1161
1162    fn paint_highlight_range(
1163        bounds: Bounds<Pixels>,
1164        start: usize,
1165        end: usize,
1166        color: Hsla,
1167        rendered_text: &RenderedText,
1168        window: &mut Window,
1169    ) {
1170        let start_pos = rendered_text.position_for_source_index(start);
1171        let end_pos = rendered_text.position_for_source_index(end);
1172        if let Some(((start_position, start_line_height), (end_position, end_line_height))) =
1173            start_pos.zip(end_pos)
1174        {
1175            if start_position.y == end_position.y {
1176                window.paint_quad(quad(
1177                    Bounds::from_corners(
1178                        start_position,
1179                        point(end_position.x, end_position.y + end_line_height),
1180                    ),
1181                    Pixels::ZERO,
1182                    color,
1183                    Edges::default(),
1184                    Hsla::transparent_black(),
1185                    BorderStyle::default(),
1186                ));
1187            } else {
1188                window.paint_quad(quad(
1189                    Bounds::from_corners(
1190                        start_position,
1191                        point(bounds.right(), start_position.y + start_line_height),
1192                    ),
1193                    Pixels::ZERO,
1194                    color,
1195                    Edges::default(),
1196                    Hsla::transparent_black(),
1197                    BorderStyle::default(),
1198                ));
1199
1200                if end_position.y > start_position.y + start_line_height {
1201                    window.paint_quad(quad(
1202                        Bounds::from_corners(
1203                            point(bounds.left(), start_position.y + start_line_height),
1204                            point(bounds.right(), end_position.y),
1205                        ),
1206                        Pixels::ZERO,
1207                        color,
1208                        Edges::default(),
1209                        Hsla::transparent_black(),
1210                        BorderStyle::default(),
1211                    ));
1212                }
1213
1214                window.paint_quad(quad(
1215                    Bounds::from_corners(
1216                        point(bounds.left(), end_position.y),
1217                        point(end_position.x, end_position.y + end_line_height),
1218                    ),
1219                    Pixels::ZERO,
1220                    color,
1221                    Edges::default(),
1222                    Hsla::transparent_black(),
1223                    BorderStyle::default(),
1224                ));
1225            }
1226        }
1227    }
1228
1229    fn paint_selection(
1230        &self,
1231        bounds: Bounds<Pixels>,
1232        rendered_text: &RenderedText,
1233        window: &mut Window,
1234        cx: &mut App,
1235    ) {
1236        let selection = self.markdown.read(cx).selection.clone();
1237        Self::paint_highlight_range(
1238            bounds,
1239            selection.start,
1240            selection.end,
1241            self.style.selection_background_color,
1242            rendered_text,
1243            window,
1244        );
1245    }
1246
1247    fn paint_search_highlights(
1248        &self,
1249        bounds: Bounds<Pixels>,
1250        rendered_text: &RenderedText,
1251        window: &mut Window,
1252        cx: &mut App,
1253    ) {
1254        let markdown = self.markdown.read(cx);
1255        let active_index = markdown.active_search_highlight;
1256        let colors = cx.theme().colors();
1257
1258        for (i, highlight_range) in markdown.search_highlights.iter().enumerate() {
1259            let color = if Some(i) == active_index {
1260                colors.search_active_match_background
1261            } else {
1262                colors.search_match_background
1263            };
1264            Self::paint_highlight_range(
1265                bounds,
1266                highlight_range.start,
1267                highlight_range.end,
1268                color,
1269                rendered_text,
1270                window,
1271            );
1272        }
1273    }
1274
1275    fn paint_mouse_listeners(
1276        &mut self,
1277        hitbox: &Hitbox,
1278        rendered_text: &RenderedText,
1279        window: &mut Window,
1280        cx: &mut App,
1281    ) {
1282        if self.style.prevent_mouse_interaction {
1283            return;
1284        }
1285
1286        let is_hovering_link = hitbox.is_hovered(window)
1287            && !self.markdown.read(cx).selection.pending
1288            && rendered_text
1289                .link_for_position(window.mouse_position())
1290                .is_some();
1291
1292        if !self.style.prevent_mouse_interaction {
1293            if is_hovering_link {
1294                window.set_cursor_style(CursorStyle::PointingHand, hitbox);
1295            } else {
1296                window.set_cursor_style(CursorStyle::IBeam, hitbox);
1297            }
1298        }
1299
1300        let on_open_url = self.on_url_click.take();
1301        let on_source_click = self.on_source_click.take();
1302
1303        self.on_mouse_event(window, cx, {
1304            let hitbox = hitbox.clone();
1305            move |markdown, event: &MouseDownEvent, phase, window, _| {
1306                if phase.capture()
1307                    && event.button == MouseButton::Right
1308                    && hitbox.is_hovered(window)
1309                {
1310                    // Capture selected text so it survives until menu item is clicked
1311                    markdown.capture_selection_for_context_menu();
1312                }
1313            }
1314        });
1315
1316        self.on_mouse_event(window, cx, {
1317            let rendered_text = rendered_text.clone();
1318            let hitbox = hitbox.clone();
1319            move |markdown, event: &MouseDownEvent, phase, window, cx| {
1320                if hitbox.is_hovered(window) {
1321                    if phase.bubble() {
1322                        if let Some(link) = rendered_text.link_for_position(event.position) {
1323                            markdown.pressed_link = Some(link.clone());
1324                        } else {
1325                            let source_index =
1326                                match rendered_text.source_index_for_position(event.position) {
1327                                    Ok(ix) | Err(ix) => ix,
1328                                };
1329                            if let Some(handler) = on_source_click.as_ref() {
1330                                let blocked = handler(source_index, event.click_count, window, cx);
1331                                if blocked {
1332                                    markdown.selection = Selection::default();
1333                                    markdown.pressed_link = None;
1334                                    window.prevent_default();
1335                                    cx.notify();
1336                                    return;
1337                                }
1338                            }
1339                            let (range, mode) = match event.click_count {
1340                                1 => {
1341                                    let range = source_index..source_index;
1342                                    (range, SelectMode::Character)
1343                                }
1344                                2 => {
1345                                    let range = rendered_text.surrounding_word_range(source_index);
1346                                    (range.clone(), SelectMode::Word(range))
1347                                }
1348                                3 => {
1349                                    let range = rendered_text.surrounding_line_range(source_index);
1350                                    (range.clone(), SelectMode::Line(range))
1351                                }
1352                                _ => {
1353                                    let range = 0..rendered_text
1354                                        .lines
1355                                        .last()
1356                                        .map(|line| line.source_end)
1357                                        .unwrap_or(0);
1358                                    (range, SelectMode::All)
1359                                }
1360                            };
1361                            markdown.selection = Selection {
1362                                start: range.start,
1363                                end: range.end,
1364                                reversed: false,
1365                                pending: true,
1366                                mode,
1367                            };
1368                            window.focus(&markdown.focus_handle, cx);
1369                        }
1370
1371                        window.prevent_default();
1372                        cx.notify();
1373                    }
1374                } else if phase.capture() && event.button == MouseButton::Left {
1375                    markdown.selection = Selection::default();
1376                    markdown.pressed_link = None;
1377                    cx.notify();
1378                }
1379            }
1380        });
1381        self.on_mouse_event(window, cx, {
1382            let rendered_text = rendered_text.clone();
1383            let hitbox = hitbox.clone();
1384            let was_hovering_link = is_hovering_link;
1385            move |markdown, event: &MouseMoveEvent, phase, window, cx| {
1386                if phase.capture() {
1387                    return;
1388                }
1389
1390                if markdown.selection.pending {
1391                    let source_index = match rendered_text.source_index_for_position(event.position)
1392                    {
1393                        Ok(ix) | Err(ix) => ix,
1394                    };
1395                    markdown.selection.set_head(source_index, &rendered_text);
1396                    markdown.autoscroll_code_block(source_index, event.position);
1397                    markdown.autoscroll_request = Some(source_index);
1398                    cx.notify();
1399                } else {
1400                    let is_hovering_link = hitbox.is_hovered(window)
1401                        && rendered_text.link_for_position(event.position).is_some();
1402                    if is_hovering_link != was_hovering_link {
1403                        cx.notify();
1404                    }
1405                }
1406            }
1407        });
1408        self.on_mouse_event(window, cx, {
1409            let rendered_text = rendered_text.clone();
1410            move |markdown, event: &MouseUpEvent, phase, window, cx| {
1411                if phase.bubble() {
1412                    if let Some(pressed_link) = markdown.pressed_link.take()
1413                        && Some(&pressed_link) == rendered_text.link_for_position(event.position)
1414                    {
1415                        if let Some(open_url) = on_open_url.as_ref() {
1416                            open_url(pressed_link.destination_url, window, cx);
1417                        } else {
1418                            cx.open_url(&pressed_link.destination_url);
1419                        }
1420                    }
1421                } else if markdown.selection.pending {
1422                    markdown.selection.pending = false;
1423                    #[cfg(any(target_os = "linux", target_os = "freebsd"))]
1424                    {
1425                        let text = rendered_text
1426                            .text_for_range(markdown.selection.start..markdown.selection.end);
1427                        cx.write_to_primary(ClipboardItem::new_string(text))
1428                    }
1429                    cx.notify();
1430                }
1431            }
1432        });
1433    }
1434
1435    fn autoscroll(
1436        &self,
1437        rendered_text: &RenderedText,
1438        window: &mut Window,
1439        cx: &mut App,
1440    ) -> Option<()> {
1441        let autoscroll_index = self
1442            .markdown
1443            .update(cx, |markdown, _| markdown.autoscroll_request.take())?;
1444        let (position, line_height) = rendered_text.position_for_source_index(autoscroll_index)?;
1445
1446        match &self.autoscroll {
1447            AutoscrollBehavior::Controlled(scroll_handle) => {
1448                let viewport = scroll_handle.bounds();
1449                let margin = line_height * 3.;
1450                let top_goal = viewport.top() + margin;
1451                let bottom_goal = viewport.bottom() - margin;
1452                let current_offset = scroll_handle.offset();
1453
1454                let new_offset_y = if position.y < top_goal {
1455                    current_offset.y + (top_goal - position.y)
1456                } else if position.y + line_height > bottom_goal {
1457                    current_offset.y + (bottom_goal - (position.y + line_height))
1458                } else {
1459                    current_offset.y
1460                };
1461
1462                scroll_handle.set_offset(point(
1463                    current_offset.x,
1464                    new_offset_y.clamp(-scroll_handle.max_offset().y, Pixels::ZERO),
1465                ));
1466            }
1467            AutoscrollBehavior::Propagate => {
1468                let text_style = self.style.base_text_style.clone();
1469                let font_id = window.text_system().resolve_font(&text_style.font());
1470                let font_size = text_style.font_size.to_pixels(window.rem_size());
1471                let em_width = window.text_system().em_width(font_id, font_size).unwrap();
1472                window.request_autoscroll(Bounds::from_corners(
1473                    point(position.x - 3. * em_width, position.y - 3. * line_height),
1474                    point(position.x + 3. * em_width, position.y + 3. * line_height),
1475                ));
1476            }
1477        }
1478        Some(())
1479    }
1480
1481    fn on_mouse_event<T: MouseEvent>(
1482        &self,
1483        window: &mut Window,
1484        _cx: &mut App,
1485        mut f: impl 'static
1486        + FnMut(&mut Markdown, &T, DispatchPhase, &mut Window, &mut Context<Markdown>),
1487    ) {
1488        window.on_mouse_event({
1489            let markdown = self.markdown.downgrade();
1490            move |event, phase, window, cx| {
1491                markdown
1492                    .update(cx, |markdown, cx| f(markdown, event, phase, window, cx))
1493                    .log_err();
1494            }
1495        });
1496    }
1497}
1498
1499impl Styled for MarkdownElement {
1500    fn style(&mut self) -> &mut StyleRefinement {
1501        &mut self.style.container_style
1502    }
1503}
1504
1505impl Element for MarkdownElement {
1506    type RequestLayoutState = RenderedMarkdown;
1507    type PrepaintState = Hitbox;
1508
1509    fn id(&self) -> Option<ElementId> {
1510        None
1511    }
1512
1513    fn source_location(&self) -> Option<&'static core::panic::Location<'static>> {
1514        None
1515    }
1516
1517    fn request_layout(
1518        &mut self,
1519        _id: Option<&GlobalElementId>,
1520        _inspector_id: Option<&gpui::InspectorElementId>,
1521        window: &mut Window,
1522        cx: &mut App,
1523    ) -> (gpui::LayoutId, Self::RequestLayoutState) {
1524        let mut builder = MarkdownElementBuilder::new(
1525            &self.style.container_style,
1526            self.style.base_text_style.clone(),
1527            self.style.syntax.clone(),
1528        );
1529        let (parsed_markdown, images, active_root_block, render_mermaid_diagrams, mermaid_state) = {
1530            let markdown = self.markdown.read(cx);
1531            (
1532                markdown.parsed_markdown.clone(),
1533                markdown.images_by_source_offset.clone(),
1534                markdown.active_root_block,
1535                markdown.options.render_mermaid_diagrams,
1536                markdown.mermaid_state.clone(),
1537            )
1538        };
1539        let markdown_end = if let Some(last) = parsed_markdown.events.last() {
1540            last.0.end
1541        } else {
1542            0
1543        };
1544        let mut code_block_ids = HashSet::default();
1545
1546        let mut current_img_block_range: Option<Range<usize>> = None;
1547        let mut handled_html_block = false;
1548        let mut rendered_mermaid_block = false;
1549        for (index, (range, event)) in parsed_markdown.events.iter().enumerate() {
1550            // Skip alt text for images that rendered
1551            if let Some(current_img_block_range) = &current_img_block_range
1552                && current_img_block_range.end > range.end
1553            {
1554                continue;
1555            }
1556
1557            if handled_html_block {
1558                if let MarkdownEvent::End(MarkdownTagEnd::HtmlBlock) = event {
1559                    handled_html_block = false;
1560                } else {
1561                    continue;
1562                }
1563            }
1564
1565            if rendered_mermaid_block {
1566                if matches!(event, MarkdownEvent::End(MarkdownTagEnd::CodeBlock)) {
1567                    rendered_mermaid_block = false;
1568                }
1569                continue;
1570            }
1571
1572            match event {
1573                MarkdownEvent::RootStart => {
1574                    if self.show_root_block_markers {
1575                        builder.push_root_block(range, markdown_end);
1576                    }
1577                }
1578                MarkdownEvent::RootEnd(root_block_index) => {
1579                    if self.show_root_block_markers {
1580                        builder.pop_root_block(
1581                            active_root_block == Some(*root_block_index),
1582                            cx.theme().colors().border,
1583                            cx.theme().colors().border_variant,
1584                        );
1585                    }
1586                }
1587                MarkdownEvent::Start(tag) => {
1588                    match tag {
1589                        MarkdownTag::Image { dest_url, .. } => {
1590                            if let Some(image) = images.get(&range.start) {
1591                                current_img_block_range = Some(range.clone());
1592                                self.push_markdown_image(
1593                                    &mut builder,
1594                                    range,
1595                                    image.clone().into(),
1596                                    None,
1597                                    None,
1598                                );
1599                            } else if let Some(source) = self
1600                                .image_resolver
1601                                .as_ref()
1602                                .and_then(|resolve| resolve(dest_url.as_ref()))
1603                            {
1604                                current_img_block_range = Some(range.clone());
1605                                self.push_markdown_image(&mut builder, range, source, None, None);
1606                            }
1607                        }
1608                        MarkdownTag::Paragraph => {
1609                            self.push_markdown_paragraph(&mut builder, range, markdown_end, None);
1610                        }
1611                        MarkdownTag::Heading { level, .. } => {
1612                            self.push_markdown_heading(
1613                                &mut builder,
1614                                *level,
1615                                range,
1616                                markdown_end,
1617                                None,
1618                            );
1619                        }
1620                        MarkdownTag::BlockQuote => {
1621                            self.push_markdown_block_quote(&mut builder, range, markdown_end);
1622                        }
1623                        MarkdownTag::CodeBlock { kind, .. } => {
1624                            if render_mermaid_diagrams
1625                                && let Some(mermaid_diagram) =
1626                                    parsed_markdown.mermaid_diagrams.get(&range.start)
1627                            {
1628                                builder.push_sourced_element(
1629                                    mermaid_diagram.content_range.clone(),
1630                                    render_mermaid_diagram(
1631                                        mermaid_diagram,
1632                                        &mermaid_state,
1633                                        &self.style,
1634                                    ),
1635                                );
1636                                rendered_mermaid_block = true;
1637                                continue;
1638                            }
1639
1640                            let language = match kind {
1641                                CodeBlockKind::Fenced => None,
1642                                CodeBlockKind::FencedLang(language) => {
1643                                    parsed_markdown.languages_by_name.get(language).cloned()
1644                                }
1645                                CodeBlockKind::FencedSrc(path_range) => parsed_markdown
1646                                    .languages_by_path
1647                                    .get(&path_range.path)
1648                                    .cloned(),
1649                                _ => None,
1650                            };
1651
1652                            let is_indented = matches!(kind, CodeBlockKind::Indented);
1653                            let scroll_handle = if self.style.code_block_overflow_x_scroll {
1654                                code_block_ids.insert(range.start);
1655                                Some(self.markdown.update(cx, |markdown, _| {
1656                                    markdown.code_block_scroll_handle(range.start)
1657                                }))
1658                            } else {
1659                                None
1660                            };
1661
1662                            match (&self.code_block_renderer, is_indented) {
1663                                (CodeBlockRenderer::Default { .. }, _) | (_, true) => {
1664                                    // This is a parent container that we can position the copy button inside.
1665                                    let parent_container =
1666                                        div().group("code_block").relative().w_full();
1667
1668                                    let mut parent_container: AnyDiv = if let Some(scroll_handle) =
1669                                        scroll_handle.as_ref()
1670                                    {
1671                                        let scrollbars = Scrollbars::new(ScrollAxes::Horizontal)
1672                                            .id(("markdown-code-block-scrollbar", range.start))
1673                                            .tracked_scroll_handle(scroll_handle)
1674                                            .with_track_along(
1675                                                ScrollAxes::Horizontal,
1676                                                cx.theme().colors().editor_background,
1677                                            )
1678                                            .notify_content();
1679
1680                                        parent_container
1681                                            .rounded_lg()
1682                                            .custom_scrollbars(scrollbars, window, cx)
1683                                            .into()
1684                                    } else {
1685                                        parent_container.into()
1686                                    };
1687
1688                                    if let CodeBlockRenderer::Default { border: true, .. } =
1689                                        &self.code_block_renderer
1690                                    {
1691                                        parent_container = parent_container
1692                                            .rounded_md()
1693                                            .border_1()
1694                                            .border_color(cx.theme().colors().border_variant);
1695                                    }
1696
1697                                    parent_container.style().refine(&self.style.code_block);
1698                                    builder.push_div(parent_container, range, markdown_end);
1699
1700                                    let code_block = div()
1701                                        .id(("code-block", range.start))
1702                                        .rounded_lg()
1703                                        .map(|mut code_block| {
1704                                            if let Some(scroll_handle) = scroll_handle.as_ref() {
1705                                                code_block.style().restrict_scroll_to_axis =
1706                                                    Some(true);
1707                                                code_block
1708                                                    .flex()
1709                                                    .overflow_x_scroll()
1710                                                    .track_scroll(scroll_handle)
1711                                            } else {
1712                                                code_block.w_full()
1713                                            }
1714                                        });
1715
1716                                    builder.push_text_style(self.style.code_block.text.to_owned());
1717                                    builder.push_code_block(language);
1718                                    builder.push_div(code_block, range, markdown_end);
1719                                }
1720                                (CodeBlockRenderer::Custom { .. }, _) => {}
1721                            }
1722                        }
1723                        MarkdownTag::HtmlBlock => {
1724                            builder.push_div(div(), range, markdown_end);
1725                            if let Some(block) = parsed_markdown.html_blocks.get(&range.start) {
1726                                self.render_html_block(block, &mut builder, markdown_end, cx);
1727                                handled_html_block = true;
1728                            }
1729                        }
1730                        MarkdownTag::List(bullet_index) => {
1731                            builder.push_list(*bullet_index);
1732                            builder.push_div(div().pl_2p5(), range, markdown_end);
1733                        }
1734                        MarkdownTag::Item => {
1735                            let bullet =
1736                                if let Some((task_range, MarkdownEvent::TaskListMarker(checked))) =
1737                                    parsed_markdown.events.get(index.saturating_add(1))
1738                                {
1739                                    let source = &parsed_markdown.source()[range.clone()];
1740                                    let checked = *checked;
1741                                    let toggle_state = if checked {
1742                                        ToggleState::Selected
1743                                    } else {
1744                                        ToggleState::Unselected
1745                                    };
1746
1747                                    let checkbox = Checkbox::new(
1748                                        ElementId::Name(source.to_string().into()),
1749                                        toggle_state,
1750                                    )
1751                                    .fill();
1752
1753                                    if let Some(on_toggle) = self.on_checkbox_toggle.clone() {
1754                                        let task_source_range = task_range.clone();
1755                                        checkbox
1756                                            .on_click(move |_state, window, cx| {
1757                                                on_toggle(
1758                                                    task_source_range.clone(),
1759                                                    !checked,
1760                                                    window,
1761                                                    cx,
1762                                                );
1763                                            })
1764                                            .into_any_element()
1765                                    } else {
1766                                        checkbox.visualization_only(true).into_any_element()
1767                                    }
1768                                } else if let Some(bullet_index) = builder.next_bullet_index() {
1769                                    div().child(format!("{}.", bullet_index)).into_any_element()
1770                                } else {
1771                                    div().child("").into_any_element()
1772                                };
1773                            self.push_markdown_list_item(&mut builder, bullet, range, markdown_end);
1774                        }
1775                        MarkdownTag::Emphasis => builder.push_text_style(TextStyleRefinement {
1776                            font_style: Some(FontStyle::Italic),
1777                            ..Default::default()
1778                        }),
1779                        MarkdownTag::Strong => builder.push_text_style(TextStyleRefinement {
1780                            font_weight: Some(FontWeight::BOLD),
1781                            ..Default::default()
1782                        }),
1783                        MarkdownTag::Strikethrough => {
1784                            builder.push_text_style(TextStyleRefinement {
1785                                strikethrough: Some(StrikethroughStyle {
1786                                    thickness: px(1.),
1787                                    color: None,
1788                                }),
1789                                ..Default::default()
1790                            })
1791                        }
1792                        MarkdownTag::Link { dest_url, .. } => {
1793                            if builder.code_block_stack.is_empty() {
1794                                builder.push_link(dest_url.clone(), range.clone());
1795                                let style = self
1796                                    .style
1797                                    .link_callback
1798                                    .as_ref()
1799                                    .and_then(|callback| callback(dest_url, cx))
1800                                    .unwrap_or_else(|| self.style.link.clone());
1801                                builder.push_text_style(style)
1802                            }
1803                        }
1804                        MarkdownTag::MetadataBlock(_) => {}
1805                        MarkdownTag::Table(alignments) => {
1806                            builder.table.start(alignments.clone());
1807
1808                            let column_count = alignments.len();
1809                            builder.push_div(
1810                                div()
1811                                    .id(("table", range.start))
1812                                    .grid()
1813                                    .grid_cols(column_count as u16)
1814                                    .when(self.style.table_columns_min_size, |this| {
1815                                        this.grid_cols_min_content(column_count as u16)
1816                                    })
1817                                    .when(!self.style.table_columns_min_size, |this| {
1818                                        this.grid_cols(column_count as u16)
1819                                    })
1820                                    .w_full()
1821                                    .mb_2()
1822                                    .border(px(1.5))
1823                                    .border_color(cx.theme().colors().border)
1824                                    .rounded_sm()
1825                                    .overflow_hidden(),
1826                                range,
1827                                markdown_end,
1828                            );
1829                        }
1830                        MarkdownTag::TableHead => {
1831                            builder.table.start_head();
1832                            builder.push_text_style(TextStyleRefinement {
1833                                font_weight: Some(FontWeight::SEMIBOLD),
1834                                ..Default::default()
1835                            });
1836                        }
1837                        MarkdownTag::TableRow => {
1838                            builder.table.start_row();
1839                        }
1840                        MarkdownTag::TableCell => {
1841                            let is_header = builder.table.in_head;
1842                            let row_index = builder.table.row_index;
1843                            let col_index = builder.table.col_index;
1844
1845                            builder.push_div(
1846                                div()
1847                                    .when(col_index > 0, |this| this.border_l_1())
1848                                    .when(row_index > 0, |this| this.border_t_1())
1849                                    .border_color(cx.theme().colors().border)
1850                                    .px_1()
1851                                    .py_0p5()
1852                                    .when(is_header, |this| {
1853                                        this.bg(cx.theme().colors().title_bar_background)
1854                                    })
1855                                    .when(!is_header && row_index % 2 == 1, |this| {
1856                                        this.bg(cx.theme().colors().panel_background)
1857                                    }),
1858                                range,
1859                                markdown_end,
1860                            );
1861                        }
1862                        _ => log::debug!("unsupported markdown tag {:?}", tag),
1863                    }
1864                }
1865                MarkdownEvent::End(tag) => match tag {
1866                    MarkdownTagEnd::Image => {
1867                        current_img_block_range.take();
1868                    }
1869                    MarkdownTagEnd::Paragraph => {
1870                        self.pop_markdown_paragraph(&mut builder);
1871                    }
1872                    MarkdownTagEnd::Heading(_) => {
1873                        self.pop_markdown_heading(&mut builder);
1874                    }
1875                    MarkdownTagEnd::BlockQuote(_kind) => {
1876                        self.pop_markdown_block_quote(&mut builder);
1877                    }
1878                    MarkdownTagEnd::CodeBlock => {
1879                        builder.trim_trailing_newline();
1880
1881                        builder.pop_div();
1882                        builder.pop_code_block();
1883                        builder.pop_text_style();
1884
1885                        if let CodeBlockRenderer::Default {
1886                            copy_button_visibility,
1887                            ..
1888                        } = &self.code_block_renderer
1889                            && *copy_button_visibility != CopyButtonVisibility::Hidden
1890                        {
1891                            builder.modify_current_div(|el| {
1892                                let content_range = parser::extract_code_block_content_range(
1893                                    &parsed_markdown.source()[range.clone()],
1894                                );
1895                                let content_range = content_range.start + range.start
1896                                    ..content_range.end + range.start;
1897
1898                                let code = parsed_markdown.source()[content_range].to_string();
1899                                let codeblock = render_copy_code_block_button(
1900                                    range.end,
1901                                    code,
1902                                    self.markdown.clone(),
1903                                );
1904                                el.child(
1905                                    h_flex()
1906                                        .w_4()
1907                                        .absolute()
1908                                        .justify_end()
1909                                        .when_else(
1910                                            *copy_button_visibility
1911                                                == CopyButtonVisibility::VisibleOnHover,
1912                                            |this| {
1913                                                this.top_0()
1914                                                    .right_0()
1915                                                    .visible_on_hover("code_block")
1916                                            },
1917                                            |this| this.top_1p5().right_1p5(),
1918                                        )
1919                                        .child(codeblock),
1920                                )
1921                            });
1922                        }
1923
1924                        // Pop the parent container.
1925                        builder.pop_div();
1926                    }
1927                    MarkdownTagEnd::HtmlBlock => builder.pop_div(),
1928                    MarkdownTagEnd::List(_) => {
1929                        builder.pop_list();
1930                        builder.pop_div();
1931                    }
1932                    MarkdownTagEnd::Item => {
1933                        self.pop_markdown_list_item(&mut builder);
1934                    }
1935                    MarkdownTagEnd::Emphasis => builder.pop_text_style(),
1936                    MarkdownTagEnd::Strong => builder.pop_text_style(),
1937                    MarkdownTagEnd::Strikethrough => builder.pop_text_style(),
1938                    MarkdownTagEnd::Link => {
1939                        if builder.code_block_stack.is_empty() {
1940                            builder.pop_text_style()
1941                        }
1942                    }
1943                    MarkdownTagEnd::Table => {
1944                        builder.pop_div();
1945                        builder.table.end();
1946                    }
1947                    MarkdownTagEnd::TableHead => {
1948                        builder.pop_text_style();
1949                        builder.table.end_head();
1950                    }
1951                    MarkdownTagEnd::TableRow => {
1952                        builder.table.end_row();
1953                    }
1954                    MarkdownTagEnd::TableCell => {
1955                        builder.replace_pending_checkbox(range);
1956                        builder.pop_div();
1957                        builder.table.end_cell();
1958                    }
1959                    _ => log::debug!("unsupported markdown tag end: {:?}", tag),
1960                },
1961                MarkdownEvent::Text => {
1962                    builder.push_text(&parsed_markdown.source[range.clone()], range.clone());
1963                }
1964                MarkdownEvent::SubstitutedText(text) => {
1965                    builder.push_text(text, range.clone());
1966                }
1967                MarkdownEvent::Code => {
1968                    builder.push_text_style(self.style.inline_code.clone());
1969                    builder.push_text(&parsed_markdown.source[range.clone()], range.clone());
1970                    builder.pop_text_style();
1971                }
1972                MarkdownEvent::Html => {
1973                    let html = &parsed_markdown.source[range.clone()];
1974                    if html.starts_with("<!--") {
1975                        builder.html_comment = true;
1976                    }
1977                    if html.trim_end().ends_with("-->") {
1978                        builder.html_comment = false;
1979                        continue;
1980                    }
1981                    if builder.html_comment {
1982                        continue;
1983                    }
1984                    builder.push_text(html, range.clone());
1985                }
1986                MarkdownEvent::InlineHtml => {
1987                    let html = &parsed_markdown.source[range.clone()];
1988                    if html.starts_with("<code>") {
1989                        builder.push_text_style(self.style.inline_code.clone());
1990                        continue;
1991                    }
1992                    if html.trim_end().starts_with("</code>") {
1993                        builder.pop_text_style();
1994                        continue;
1995                    }
1996                    builder.push_text(&parsed_markdown.source[range.clone()], range.clone());
1997                }
1998                MarkdownEvent::Rule => {
1999                    builder.push_div(
2000                        div()
2001                            .border_b_1()
2002                            .my_2()
2003                            .border_color(self.style.rule_color),
2004                        range,
2005                        markdown_end,
2006                    );
2007                    builder.pop_div()
2008                }
2009                MarkdownEvent::SoftBreak => builder.push_text(" ", range.clone()),
2010                MarkdownEvent::HardBreak => builder.push_text("\n", range.clone()),
2011                MarkdownEvent::TaskListMarker(_) => {
2012                    // handled inside the `MarkdownTag::Item` case
2013                }
2014                _ => log::debug!("unsupported markdown event {:?}", event),
2015            }
2016        }
2017        if self.style.code_block_overflow_x_scroll {
2018            let code_block_ids = code_block_ids;
2019            self.markdown.update(cx, move |markdown, _| {
2020                markdown.retain_code_block_scroll_handles(&code_block_ids);
2021            });
2022        } else {
2023            self.markdown
2024                .update(cx, |markdown, _| markdown.clear_code_block_scroll_handles());
2025        }
2026        let mut rendered_markdown = builder.build();
2027        let child_layout_id = rendered_markdown.element.request_layout(window, cx);
2028        let layout_id = window.request_layout(gpui::Style::default(), [child_layout_id], cx);
2029        (layout_id, rendered_markdown)
2030    }
2031
2032    fn prepaint(
2033        &mut self,
2034        _id: Option<&GlobalElementId>,
2035        _inspector_id: Option<&gpui::InspectorElementId>,
2036        bounds: Bounds<Pixels>,
2037        rendered_markdown: &mut Self::RequestLayoutState,
2038        window: &mut Window,
2039        cx: &mut App,
2040    ) -> Self::PrepaintState {
2041        let focus_handle = self.markdown.read(cx).focus_handle.clone();
2042        window.set_focus_handle(&focus_handle, cx);
2043        window.set_view_id(self.markdown.entity_id());
2044
2045        let hitbox = window.insert_hitbox(bounds, HitboxBehavior::Normal);
2046        rendered_markdown.element.prepaint(window, cx);
2047        self.autoscroll(&rendered_markdown.text, window, cx);
2048        hitbox
2049    }
2050
2051    fn paint(
2052        &mut self,
2053        _id: Option<&GlobalElementId>,
2054        _inspector_id: Option<&gpui::InspectorElementId>,
2055        bounds: Bounds<Pixels>,
2056        rendered_markdown: &mut Self::RequestLayoutState,
2057        hitbox: &mut Self::PrepaintState,
2058        window: &mut Window,
2059        cx: &mut App,
2060    ) {
2061        let mut context = KeyContext::default();
2062        context.add("Markdown");
2063        window.set_key_context(context);
2064        window.on_action(std::any::TypeId::of::<crate::Copy>(), {
2065            let entity = self.markdown.clone();
2066            let text = rendered_markdown.text.clone();
2067            move |_, phase, window, cx| {
2068                let text = text.clone();
2069                if phase == DispatchPhase::Bubble {
2070                    entity.update(cx, move |this, cx| this.copy(&text, window, cx))
2071                }
2072            }
2073        });
2074        window.on_action(std::any::TypeId::of::<crate::CopyAsMarkdown>(), {
2075            let entity = self.markdown.clone();
2076            move |_, phase, window, cx| {
2077                if phase == DispatchPhase::Bubble {
2078                    entity.update(cx, move |this, cx| this.copy_as_markdown(window, cx))
2079                }
2080            }
2081        });
2082
2083        self.paint_mouse_listeners(hitbox, &rendered_markdown.text, window, cx);
2084        rendered_markdown.element.paint(window, cx);
2085        self.paint_search_highlights(bounds, &rendered_markdown.text, window, cx);
2086        self.paint_selection(bounds, &rendered_markdown.text, window, cx);
2087    }
2088}
2089
2090fn apply_heading_style(
2091    mut heading: Div,
2092    level: pulldown_cmark::HeadingLevel,
2093    custom_styles: Option<&HeadingLevelStyles>,
2094) -> Div {
2095    heading = match level {
2096        pulldown_cmark::HeadingLevel::H1 => heading.text_3xl(),
2097        pulldown_cmark::HeadingLevel::H2 => heading.text_2xl(),
2098        pulldown_cmark::HeadingLevel::H3 => heading.text_xl(),
2099        pulldown_cmark::HeadingLevel::H4 => heading.text_lg(),
2100        pulldown_cmark::HeadingLevel::H5 => heading.text_base(),
2101        pulldown_cmark::HeadingLevel::H6 => heading.text_sm(),
2102    };
2103
2104    if let Some(styles) = custom_styles {
2105        let style_opt = match level {
2106            pulldown_cmark::HeadingLevel::H1 => &styles.h1,
2107            pulldown_cmark::HeadingLevel::H2 => &styles.h2,
2108            pulldown_cmark::HeadingLevel::H3 => &styles.h3,
2109            pulldown_cmark::HeadingLevel::H4 => &styles.h4,
2110            pulldown_cmark::HeadingLevel::H5 => &styles.h5,
2111            pulldown_cmark::HeadingLevel::H6 => &styles.h6,
2112        };
2113
2114        if let Some(style) = style_opt {
2115            heading.style().text = style.clone();
2116        }
2117    }
2118
2119    heading
2120}
2121
2122fn render_copy_code_block_button(
2123    id: usize,
2124    code: String,
2125    markdown: Entity<Markdown>,
2126) -> impl IntoElement {
2127    let id = ElementId::named_usize("copy-markdown-code", id);
2128
2129    CopyButton::new(id.clone(), code.clone()).custom_on_click({
2130        let markdown = markdown;
2131        move |_window, cx| {
2132            let id = id.clone();
2133            markdown.update(cx, |this, cx| {
2134                this.copied_code_blocks.insert(id.clone());
2135
2136                cx.write_to_clipboard(ClipboardItem::new_string(code.clone()));
2137
2138                cx.spawn(async move |this, cx| {
2139                    cx.background_executor().timer(Duration::from_secs(2)).await;
2140
2141                    cx.update(|cx| {
2142                        this.update(cx, |this, cx| {
2143                            this.copied_code_blocks.remove(&id);
2144                            cx.notify();
2145                        })
2146                    })
2147                    .ok();
2148                })
2149                .detach();
2150            });
2151        }
2152    })
2153}
2154
2155impl IntoElement for MarkdownElement {
2156    type Element = Self;
2157
2158    fn into_element(self) -> Self::Element {
2159        self
2160    }
2161}
2162
2163pub enum AnyDiv {
2164    Div(Div),
2165    Stateful(Stateful<Div>),
2166}
2167
2168impl AnyDiv {
2169    fn into_any_element(self) -> AnyElement {
2170        match self {
2171            Self::Div(div) => div.into_any_element(),
2172            Self::Stateful(div) => div.into_any_element(),
2173        }
2174    }
2175}
2176
2177impl From<Div> for AnyDiv {
2178    fn from(value: Div) -> Self {
2179        Self::Div(value)
2180    }
2181}
2182
2183impl From<Stateful<Div>> for AnyDiv {
2184    fn from(value: Stateful<Div>) -> Self {
2185        Self::Stateful(value)
2186    }
2187}
2188
2189impl Styled for AnyDiv {
2190    fn style(&mut self) -> &mut StyleRefinement {
2191        match self {
2192            Self::Div(div) => div.style(),
2193            Self::Stateful(div) => div.style(),
2194        }
2195    }
2196}
2197
2198impl ParentElement for AnyDiv {
2199    fn extend(&mut self, elements: impl IntoIterator<Item = AnyElement>) {
2200        match self {
2201            Self::Div(div) => div.extend(elements),
2202            Self::Stateful(div) => div.extend(elements),
2203        }
2204    }
2205}
2206
2207#[derive(Default)]
2208struct TableState {
2209    alignments: Vec<Alignment>,
2210    in_head: bool,
2211    row_index: usize,
2212    col_index: usize,
2213}
2214
2215impl TableState {
2216    fn start(&mut self, alignments: Vec<Alignment>) {
2217        self.alignments = alignments;
2218        self.in_head = false;
2219        self.row_index = 0;
2220        self.col_index = 0;
2221    }
2222
2223    fn end(&mut self) {
2224        self.alignments.clear();
2225        self.in_head = false;
2226        self.row_index = 0;
2227        self.col_index = 0;
2228    }
2229
2230    fn start_head(&mut self) {
2231        self.in_head = true;
2232    }
2233
2234    fn end_head(&mut self) {
2235        self.in_head = false;
2236    }
2237
2238    fn start_row(&mut self) {
2239        self.col_index = 0;
2240    }
2241
2242    fn end_row(&mut self) {
2243        self.row_index += 1;
2244    }
2245
2246    fn end_cell(&mut self) {
2247        self.col_index += 1;
2248    }
2249}
2250
2251struct MarkdownElementBuilder {
2252    div_stack: Vec<AnyDiv>,
2253    rendered_lines: Vec<RenderedLine>,
2254    pending_line: PendingLine,
2255    rendered_links: Vec<RenderedLink>,
2256    current_source_index: usize,
2257    html_comment: bool,
2258    base_text_style: TextStyle,
2259    text_style_stack: Vec<TextStyleRefinement>,
2260    code_block_stack: Vec<Option<Arc<Language>>>,
2261    list_stack: Vec<ListStackEntry>,
2262    table: TableState,
2263    syntax_theme: Arc<SyntaxTheme>,
2264}
2265
2266#[derive(Default)]
2267struct PendingLine {
2268    text: String,
2269    runs: Vec<TextRun>,
2270    source_mappings: Vec<SourceMapping>,
2271}
2272
2273struct ListStackEntry {
2274    bullet_index: Option<u64>,
2275}
2276
2277impl MarkdownElementBuilder {
2278    fn new(
2279        container_style: &StyleRefinement,
2280        base_text_style: TextStyle,
2281        syntax_theme: Arc<SyntaxTheme>,
2282    ) -> Self {
2283        Self {
2284            div_stack: vec![{
2285                let mut base_div = div();
2286                base_div.style().refine(container_style);
2287                base_div.debug_selector(|| "inner".into()).into()
2288            }],
2289            rendered_lines: Vec::new(),
2290            pending_line: PendingLine::default(),
2291            rendered_links: Vec::new(),
2292            current_source_index: 0,
2293            html_comment: false,
2294            base_text_style,
2295            text_style_stack: Vec::new(),
2296            code_block_stack: Vec::new(),
2297            list_stack: Vec::new(),
2298            table: TableState::default(),
2299            syntax_theme,
2300        }
2301    }
2302
2303    fn push_text_style(&mut self, style: TextStyleRefinement) {
2304        self.text_style_stack.push(style);
2305    }
2306
2307    fn text_style(&self) -> TextStyle {
2308        let mut style = self.base_text_style.clone();
2309        for refinement in &self.text_style_stack {
2310            style.refine(refinement);
2311        }
2312        style
2313    }
2314
2315    fn pop_text_style(&mut self) {
2316        self.text_style_stack.pop();
2317    }
2318
2319    fn push_div(&mut self, div: impl Into<AnyDiv>, range: &Range<usize>, markdown_end: usize) {
2320        let mut div = div.into();
2321        self.flush_text();
2322
2323        if range.start == 0 {
2324            // Remove the top margin on the first element.
2325            div.style().refine(&StyleRefinement {
2326                margin: gpui::EdgesRefinement {
2327                    top: Some(Length::Definite(px(0.).into())),
2328                    left: None,
2329                    right: None,
2330                    bottom: None,
2331                },
2332                ..Default::default()
2333            });
2334        }
2335
2336        if range.end == markdown_end {
2337            div.style().refine(&StyleRefinement {
2338                margin: gpui::EdgesRefinement {
2339                    top: None,
2340                    left: None,
2341                    right: None,
2342                    bottom: Some(Length::Definite(rems(0.).into())),
2343                },
2344                ..Default::default()
2345            });
2346        }
2347
2348        self.div_stack.push(div);
2349    }
2350
2351    fn push_root_block(&mut self, range: &Range<usize>, markdown_end: usize) {
2352        self.push_div(
2353            div().group("markdown-root-block").relative(),
2354            range,
2355            markdown_end,
2356        );
2357        self.push_div(div().pl_4(), range, markdown_end);
2358    }
2359
2360    fn modify_current_div(&mut self, f: impl FnOnce(AnyDiv) -> AnyDiv) {
2361        self.flush_text();
2362        if let Some(div) = self.div_stack.pop() {
2363            self.div_stack.push(f(div));
2364        }
2365    }
2366
2367    fn pop_root_block(
2368        &mut self,
2369        is_active: bool,
2370        active_gutter_color: Hsla,
2371        hovered_gutter_color: Hsla,
2372    ) {
2373        self.pop_div();
2374        self.modify_current_div(|el| {
2375            el.child(
2376                div()
2377                    .h_full()
2378                    .w(px(4.0))
2379                    .when(is_active, |this| this.bg(active_gutter_color))
2380                    .group_hover("markdown-root-block", |this| {
2381                        if is_active {
2382                            this
2383                        } else {
2384                            this.bg(hovered_gutter_color)
2385                        }
2386                    })
2387                    .rounded_xs()
2388                    .absolute()
2389                    .left_0()
2390                    .top_0(),
2391            )
2392        });
2393        self.pop_div();
2394    }
2395
2396    fn pop_div(&mut self) {
2397        self.flush_text();
2398        let div = self.div_stack.pop().unwrap().into_any_element();
2399        self.div_stack.last_mut().unwrap().extend(iter::once(div));
2400    }
2401
2402    fn push_sourced_element(&mut self, source_range: Range<usize>, element: impl Into<AnyElement>) {
2403        self.flush_text();
2404        let anchor = self.render_source_anchor(source_range);
2405        self.div_stack.last_mut().unwrap().extend([{
2406            div()
2407                .relative()
2408                .child(anchor)
2409                .child(element.into())
2410                .into_any_element()
2411        }]);
2412    }
2413
2414    fn push_list(&mut self, bullet_index: Option<u64>) {
2415        self.list_stack.push(ListStackEntry { bullet_index });
2416    }
2417
2418    fn next_bullet_index(&mut self) -> Option<u64> {
2419        self.list_stack.last_mut().and_then(|entry| {
2420            let item_index = entry.bullet_index.as_mut()?;
2421            *item_index += 1;
2422            Some(*item_index - 1)
2423        })
2424    }
2425
2426    fn pop_list(&mut self) {
2427        self.list_stack.pop();
2428    }
2429
2430    fn push_code_block(&mut self, language: Option<Arc<Language>>) {
2431        self.code_block_stack.push(language);
2432    }
2433
2434    fn pop_code_block(&mut self) {
2435        self.code_block_stack.pop();
2436    }
2437
2438    fn push_link(&mut self, destination_url: SharedString, source_range: Range<usize>) {
2439        self.rendered_links.push(RenderedLink {
2440            source_range,
2441            destination_url,
2442        });
2443    }
2444
2445    fn push_text(&mut self, text: &str, source_range: Range<usize>) {
2446        self.pending_line.source_mappings.push(SourceMapping {
2447            rendered_index: self.pending_line.text.len(),
2448            source_index: source_range.start,
2449        });
2450        self.pending_line.text.push_str(text);
2451        self.current_source_index = source_range.end;
2452
2453        if let Some(Some(language)) = self.code_block_stack.last() {
2454            let mut offset = 0;
2455            for (range, highlight_id) in language.highlight_text(&Rope::from(text), 0..text.len()) {
2456                if range.start > offset {
2457                    self.pending_line
2458                        .runs
2459                        .push(self.text_style().to_run(range.start - offset));
2460                }
2461
2462                let mut run_style = self.text_style();
2463                if let Some(highlight) = self.syntax_theme.get(highlight_id).cloned() {
2464                    run_style = run_style.highlight(highlight);
2465                }
2466
2467                self.pending_line.runs.push(run_style.to_run(range.len()));
2468                offset = range.end;
2469            }
2470
2471            if offset < text.len() {
2472                self.pending_line
2473                    .runs
2474                    .push(self.text_style().to_run(text.len() - offset));
2475            }
2476        } else {
2477            self.pending_line
2478                .runs
2479                .push(self.text_style().to_run(text.len()));
2480        }
2481    }
2482
2483    fn trim_trailing_newline(&mut self) {
2484        if self.pending_line.text.ends_with('\n') {
2485            self.pending_line
2486                .text
2487                .truncate(self.pending_line.text.len() - 1);
2488            self.pending_line.runs.last_mut().unwrap().len -= 1;
2489            self.current_source_index -= 1;
2490        }
2491    }
2492
2493    fn replace_pending_checkbox(&mut self, source_range: &Range<usize>) {
2494        let trimmed = self.pending_line.text.trim();
2495        if trimmed == "[x]" || trimmed == "[X]" || trimmed == "[ ]" {
2496            let checked = trimmed != "[ ]";
2497            self.pending_line = PendingLine::default();
2498            let checkbox = Checkbox::new(
2499                ElementId::Name(
2500                    format!("table_checkbox_{}_{}", source_range.start, source_range.end).into(),
2501                ),
2502                if checked {
2503                    ToggleState::Selected
2504                } else {
2505                    ToggleState::Unselected
2506                },
2507            )
2508            .fill()
2509            .visualization_only(true)
2510            .into_any_element();
2511            self.div_stack.last_mut().unwrap().extend([checkbox]);
2512        }
2513    }
2514
2515    fn render_source_anchor(&mut self, source_range: Range<usize>) -> AnyElement {
2516        let mut text_style = self.base_text_style.clone();
2517        text_style.color = Hsla::transparent_black();
2518        let text = "\u{200B}";
2519        let styled_text = StyledText::new(text).with_runs(vec![text_style.to_run(text.len())]);
2520        self.rendered_lines.push(RenderedLine {
2521            layout: styled_text.layout().clone(),
2522            source_mappings: vec![SourceMapping {
2523                rendered_index: 0,
2524                source_index: source_range.start,
2525            }],
2526            source_end: source_range.end,
2527            language: None,
2528        });
2529        div()
2530            .absolute()
2531            .top_0()
2532            .left_0()
2533            .opacity(0.)
2534            .child(styled_text)
2535            .into_any_element()
2536    }
2537
2538    fn flush_text(&mut self) {
2539        let line = mem::take(&mut self.pending_line);
2540        if line.text.is_empty() {
2541            return;
2542        }
2543
2544        let text = StyledText::new(line.text).with_runs(line.runs);
2545        self.rendered_lines.push(RenderedLine {
2546            layout: text.layout().clone(),
2547            source_mappings: line.source_mappings,
2548            source_end: self.current_source_index,
2549            language: self.code_block_stack.last().cloned().flatten(),
2550        });
2551        self.div_stack.last_mut().unwrap().extend([text.into_any()]);
2552    }
2553
2554    fn build(mut self) -> RenderedMarkdown {
2555        debug_assert_eq!(self.div_stack.len(), 1);
2556        self.flush_text();
2557        RenderedMarkdown {
2558            element: self.div_stack.pop().unwrap().into_any_element(),
2559            text: RenderedText {
2560                lines: self.rendered_lines.into(),
2561                links: self.rendered_links.into(),
2562            },
2563        }
2564    }
2565}
2566
2567struct RenderedLine {
2568    layout: TextLayout,
2569    source_mappings: Vec<SourceMapping>,
2570    source_end: usize,
2571    language: Option<Arc<Language>>,
2572}
2573
2574impl RenderedLine {
2575    fn rendered_index_for_source_index(&self, source_index: usize) -> usize {
2576        if source_index >= self.source_end {
2577            return self.layout.len();
2578        }
2579
2580        let mapping = match self
2581            .source_mappings
2582            .binary_search_by_key(&source_index, |probe| probe.source_index)
2583        {
2584            Ok(ix) => &self.source_mappings[ix],
2585            Err(ix) => &self.source_mappings[ix - 1],
2586        };
2587        (mapping.rendered_index + (source_index - mapping.source_index)).min(self.layout.len())
2588    }
2589
2590    fn source_index_for_rendered_index(&self, rendered_index: usize) -> usize {
2591        if rendered_index >= self.layout.len() {
2592            return self.source_end;
2593        }
2594
2595        let mapping = match self
2596            .source_mappings
2597            .binary_search_by_key(&rendered_index, |probe| probe.rendered_index)
2598        {
2599            Ok(ix) => &self.source_mappings[ix],
2600            Err(ix) => &self.source_mappings[ix - 1],
2601        };
2602        mapping.source_index + (rendered_index - mapping.rendered_index)
2603    }
2604
2605    /// Returns the source index for use as an exclusive range end at a word/selection boundary.
2606    /// When the rendered index is exactly at the start of a segment with a gap from the previous
2607    /// segment (e.g., after stripped markdown syntax like backticks), this returns the end of the
2608    /// previous segment rather than the start of the current one.
2609    fn source_index_for_exclusive_rendered_end(&self, rendered_index: usize) -> usize {
2610        if rendered_index >= self.layout.len() {
2611            return self.source_end;
2612        }
2613
2614        let ix = match self
2615            .source_mappings
2616            .binary_search_by_key(&rendered_index, |probe| probe.rendered_index)
2617        {
2618            Ok(ix) => ix,
2619            Err(ix) => {
2620                return self.source_mappings[ix - 1].source_index
2621                    + (rendered_index - self.source_mappings[ix - 1].rendered_index);
2622            }
2623        };
2624
2625        // Exact match at the start of a segment. Check if there's a gap from the previous segment.
2626        if ix > 0 {
2627            let prev_mapping = &self.source_mappings[ix - 1];
2628            let mapping = &self.source_mappings[ix];
2629            let prev_segment_len = mapping.rendered_index - prev_mapping.rendered_index;
2630            let prev_source_end = prev_mapping.source_index + prev_segment_len;
2631            if prev_source_end < mapping.source_index {
2632                return prev_source_end;
2633            }
2634        }
2635
2636        self.source_mappings[ix].source_index
2637    }
2638
2639    fn source_index_for_position(&self, position: Point<Pixels>) -> Result<usize, usize> {
2640        let line_rendered_index;
2641        let out_of_bounds;
2642        match self.layout.index_for_position(position) {
2643            Ok(ix) => {
2644                line_rendered_index = ix;
2645                out_of_bounds = false;
2646            }
2647            Err(ix) => {
2648                line_rendered_index = ix;
2649                out_of_bounds = true;
2650            }
2651        };
2652        let source_index = self.source_index_for_rendered_index(line_rendered_index);
2653        if out_of_bounds {
2654            Err(source_index)
2655        } else {
2656            Ok(source_index)
2657        }
2658    }
2659}
2660
2661#[derive(Copy, Clone, Debug, Default)]
2662struct SourceMapping {
2663    rendered_index: usize,
2664    source_index: usize,
2665}
2666
2667pub struct RenderedMarkdown {
2668    element: AnyElement,
2669    text: RenderedText,
2670}
2671
2672#[derive(Clone)]
2673struct RenderedText {
2674    lines: Rc<[RenderedLine]>,
2675    links: Rc<[RenderedLink]>,
2676}
2677
2678#[derive(Debug, Clone, Eq, PartialEq)]
2679struct RenderedLink {
2680    source_range: Range<usize>,
2681    destination_url: SharedString,
2682}
2683
2684impl RenderedText {
2685    fn source_index_for_position(&self, position: Point<Pixels>) -> Result<usize, usize> {
2686        let mut lines = self.lines.iter().peekable();
2687        let mut fallback_line: Option<&RenderedLine> = None;
2688
2689        while let Some(line) = lines.next() {
2690            let line_bounds = line.layout.bounds();
2691
2692            // Exact match: position is within bounds (handles overlapping bounds like table columns)
2693            if line_bounds.contains(&position) {
2694                return line.source_index_for_position(position);
2695            }
2696
2697            // Track fallback for Y-coordinate based matching
2698            if position.y <= line_bounds.bottom() && fallback_line.is_none() {
2699                fallback_line = Some(line);
2700            }
2701
2702            // Handle gap between lines
2703            if position.y > line_bounds.bottom() {
2704                if let Some(next_line) = lines.peek()
2705                    && position.y < next_line.layout.bounds().top()
2706                {
2707                    return Err(line.source_end);
2708                }
2709            }
2710        }
2711
2712        // Fall back to Y-coordinate matched line
2713        if let Some(line) = fallback_line {
2714            return line.source_index_for_position(position);
2715        }
2716
2717        Err(self.lines.last().map_or(0, |line| line.source_end))
2718    }
2719
2720    fn position_for_source_index(&self, source_index: usize) -> Option<(Point<Pixels>, Pixels)> {
2721        for line in self.lines.iter() {
2722            let line_source_start = line.source_mappings.first().unwrap().source_index;
2723            if source_index < line_source_start {
2724                break;
2725            } else if source_index > line.source_end {
2726                continue;
2727            } else {
2728                let line_height = line.layout.line_height();
2729                let rendered_index_within_line = line.rendered_index_for_source_index(source_index);
2730                let position = line.layout.position_for_index(rendered_index_within_line)?;
2731                return Some((position, line_height));
2732            }
2733        }
2734        None
2735    }
2736
2737    fn surrounding_word_range(&self, source_index: usize) -> Range<usize> {
2738        for line in self.lines.iter() {
2739            if source_index > line.source_end {
2740                continue;
2741            }
2742
2743            let line_rendered_start = line.source_mappings.first().unwrap().rendered_index;
2744            let rendered_index_in_line =
2745                line.rendered_index_for_source_index(source_index) - line_rendered_start;
2746            let text = line.layout.text();
2747
2748            let scope = line.language.as_ref().map(|l| l.default_scope());
2749            let classifier = CharClassifier::new(scope);
2750
2751            let mut prev_chars = text[..rendered_index_in_line].chars().rev().peekable();
2752            let mut next_chars = text[rendered_index_in_line..].chars().peekable();
2753
2754            let word_kind = std::cmp::max(
2755                prev_chars.peek().map(|&c| classifier.kind(c)),
2756                next_chars.peek().map(|&c| classifier.kind(c)),
2757            );
2758
2759            let mut start = rendered_index_in_line;
2760            for c in prev_chars {
2761                if Some(classifier.kind(c)) == word_kind {
2762                    start -= c.len_utf8();
2763                } else {
2764                    break;
2765                }
2766            }
2767
2768            let mut end = rendered_index_in_line;
2769            for c in next_chars {
2770                if Some(classifier.kind(c)) == word_kind {
2771                    end += c.len_utf8();
2772                } else {
2773                    break;
2774                }
2775            }
2776
2777            return line.source_index_for_rendered_index(line_rendered_start + start)
2778                ..line.source_index_for_exclusive_rendered_end(line_rendered_start + end);
2779        }
2780
2781        source_index..source_index
2782    }
2783
2784    fn surrounding_line_range(&self, source_index: usize) -> Range<usize> {
2785        for line in self.lines.iter() {
2786            if source_index > line.source_end {
2787                continue;
2788            }
2789            let line_source_start = line.source_mappings.first().unwrap().source_index;
2790            return line_source_start..line.source_end;
2791        }
2792
2793        source_index..source_index
2794    }
2795
2796    fn text_for_range(&self, range: Range<usize>) -> String {
2797        let mut accumulator = String::new();
2798
2799        for line in self.lines.iter() {
2800            if range.start > line.source_end {
2801                continue;
2802            }
2803            let line_source_start = line.source_mappings.first().unwrap().source_index;
2804            if range.end < line_source_start {
2805                break;
2806            }
2807
2808            let text = line.layout.text();
2809
2810            let start = if range.start < line_source_start {
2811                0
2812            } else {
2813                line.rendered_index_for_source_index(range.start)
2814            };
2815            let end = if range.end > line.source_end {
2816                line.rendered_index_for_source_index(line.source_end)
2817            } else {
2818                line.rendered_index_for_source_index(range.end)
2819            }
2820            .min(text.len());
2821
2822            accumulator.push_str(&text[start..end]);
2823            accumulator.push('\n');
2824        }
2825        // Remove trailing newline
2826        accumulator.pop();
2827        accumulator
2828    }
2829
2830    fn link_for_position(&self, position: Point<Pixels>) -> Option<&RenderedLink> {
2831        let source_index = self.source_index_for_position(position).ok()?;
2832        self.links
2833            .iter()
2834            .find(|link| link.source_range.contains(&source_index))
2835    }
2836}
2837
2838#[cfg(test)]
2839mod tests {
2840    use super::*;
2841    use gpui::{TestAppContext, size};
2842    use language::{Language, LanguageConfig, LanguageMatcher};
2843    use std::sync::Arc;
2844
2845    fn ensure_theme_initialized(cx: &mut TestAppContext) {
2846        cx.update(|cx| {
2847            if !cx.has_global::<settings::SettingsStore>() {
2848                settings::init(cx);
2849            }
2850            if !cx.has_global::<theme::GlobalTheme>() {
2851                theme_settings::init(theme::LoadThemes::JustBase, cx);
2852            }
2853        });
2854    }
2855
2856    #[gpui::test]
2857    fn test_mappings(cx: &mut TestAppContext) {
2858        // Formatting.
2859        assert_mappings(
2860            &render_markdown("He*l*lo", cx),
2861            vec![vec![(0, 0), (1, 1), (2, 3), (3, 5), (4, 6), (5, 7)]],
2862        );
2863
2864        // Multiple lines.
2865        assert_mappings(
2866            &render_markdown("Hello\n\nWorld", cx),
2867            vec![
2868                vec![(0, 0), (1, 1), (2, 2), (3, 3), (4, 4), (5, 5)],
2869                vec![(0, 7), (1, 8), (2, 9), (3, 10), (4, 11), (5, 12)],
2870            ],
2871        );
2872
2873        // Multi-byte characters.
2874        assert_mappings(
2875            &render_markdown("αβγ\n\nδεζ", cx),
2876            vec![
2877                vec![(0, 0), (2, 2), (4, 4), (6, 6)],
2878                vec![(0, 8), (2, 10), (4, 12), (6, 14)],
2879            ],
2880        );
2881
2882        // Smart quotes.
2883        assert_mappings(&render_markdown("\"", cx), vec![vec![(0, 0), (3, 1)]]);
2884        assert_mappings(
2885            &render_markdown("\"hey\"", cx),
2886            vec![vec![(0, 0), (3, 1), (4, 2), (5, 3), (6, 4), (9, 5)]],
2887        );
2888
2889        // HTML Comments are ignored
2890        assert_mappings(
2891            &render_markdown(
2892                "<!--\nrdoc-file=string.c\n- str.intern   -> symbol\n- str.to_sym   -> symbol\n-->\nReturns",
2893                cx,
2894            ),
2895            vec![vec![
2896                (0, 78),
2897                (1, 79),
2898                (2, 80),
2899                (3, 81),
2900                (4, 82),
2901                (5, 83),
2902                (6, 84),
2903            ]],
2904        );
2905    }
2906
2907    fn render_markdown(markdown: &str, cx: &mut TestAppContext) -> RenderedText {
2908        render_markdown_with_language_registry(markdown, None, cx)
2909    }
2910
2911    fn render_markdown_with_language_registry(
2912        markdown: &str,
2913        language_registry: Option<Arc<LanguageRegistry>>,
2914        cx: &mut TestAppContext,
2915    ) -> RenderedText {
2916        render_markdown_with_options(markdown, language_registry, MarkdownOptions::default(), cx)
2917    }
2918
2919    fn render_markdown_with_options(
2920        markdown: &str,
2921        language_registry: Option<Arc<LanguageRegistry>>,
2922        options: MarkdownOptions,
2923        cx: &mut TestAppContext,
2924    ) -> RenderedText {
2925        struct TestWindow;
2926
2927        impl Render for TestWindow {
2928            fn render(&mut self, _: &mut Window, _: &mut Context<Self>) -> impl IntoElement {
2929                div()
2930            }
2931        }
2932
2933        ensure_theme_initialized(cx);
2934
2935        let (_, cx) = cx.add_window_view(|_, _| TestWindow);
2936        let markdown = cx.new(|cx| {
2937            Markdown::new_with_options(
2938                markdown.to_string().into(),
2939                language_registry,
2940                None,
2941                options,
2942                cx,
2943            )
2944        });
2945        cx.run_until_parked();
2946        let (rendered, _) = cx.draw(
2947            Default::default(),
2948            size(px(600.0), px(600.0)),
2949            |_window, _cx| {
2950                MarkdownElement::new(markdown, MarkdownStyle::default()).code_block_renderer(
2951                    CodeBlockRenderer::Default {
2952                        copy_button_visibility: CopyButtonVisibility::Hidden,
2953                        border: false,
2954                    },
2955                )
2956            },
2957        );
2958        rendered.text
2959    }
2960
2961    #[gpui::test]
2962    fn test_surrounding_word_range(cx: &mut TestAppContext) {
2963        let rendered = render_markdown("Hello world tesεζ", cx);
2964
2965        // Test word selection for "Hello"
2966        let word_range = rendered.surrounding_word_range(2); // Simulate click on 'l' in "Hello"
2967        let selected_text = rendered.text_for_range(word_range);
2968        assert_eq!(selected_text, "Hello");
2969
2970        // Test word selection for "world"
2971        let word_range = rendered.surrounding_word_range(7); // Simulate click on 'o' in "world"
2972        let selected_text = rendered.text_for_range(word_range);
2973        assert_eq!(selected_text, "world");
2974
2975        // Test word selection for "tesεζ"
2976        let word_range = rendered.surrounding_word_range(14); // Simulate click on 's' in "tesεζ"
2977        let selected_text = rendered.text_for_range(word_range);
2978        assert_eq!(selected_text, "tesεζ");
2979
2980        // Test word selection at word boundary (space)
2981        let word_range = rendered.surrounding_word_range(5); // Simulate click on space between "Hello" and "world", expect highlighting word to the left
2982        let selected_text = rendered.text_for_range(word_range);
2983        assert_eq!(selected_text, "Hello");
2984    }
2985
2986    #[gpui::test]
2987    fn test_surrounding_line_range(cx: &mut TestAppContext) {
2988        let rendered = render_markdown("First line\n\nSecond line\n\nThird lineεζ", cx);
2989
2990        // Test getting line range for first line
2991        let line_range = rendered.surrounding_line_range(5); // Simulate click somewhere in first line
2992        let selected_text = rendered.text_for_range(line_range);
2993        assert_eq!(selected_text, "First line");
2994
2995        // Test getting line range for second line
2996        let line_range = rendered.surrounding_line_range(13); // Simulate click at beginning in second line
2997        let selected_text = rendered.text_for_range(line_range);
2998        assert_eq!(selected_text, "Second line");
2999
3000        // Test getting line range for third line
3001        let line_range = rendered.surrounding_line_range(37); // Simulate click at end of third line with multi-byte chars
3002        let selected_text = rendered.text_for_range(line_range);
3003        assert_eq!(selected_text, "Third lineεζ");
3004    }
3005
3006    #[gpui::test]
3007    fn test_selection_head_movement(cx: &mut TestAppContext) {
3008        let rendered = render_markdown("Hello world test", cx);
3009
3010        let mut selection = Selection {
3011            start: 5,
3012            end: 5,
3013            reversed: false,
3014            pending: false,
3015            mode: SelectMode::Character,
3016        };
3017
3018        // Test forward selection
3019        selection.set_head(10, &rendered);
3020        assert_eq!(selection.start, 5);
3021        assert_eq!(selection.end, 10);
3022        assert!(!selection.reversed);
3023        assert_eq!(selection.tail(), 5);
3024
3025        // Test backward selection
3026        selection.set_head(2, &rendered);
3027        assert_eq!(selection.start, 2);
3028        assert_eq!(selection.end, 5);
3029        assert!(selection.reversed);
3030        assert_eq!(selection.tail(), 5);
3031
3032        // Test forward selection again from reversed state
3033        selection.set_head(15, &rendered);
3034        assert_eq!(selection.start, 5);
3035        assert_eq!(selection.end, 15);
3036        assert!(!selection.reversed);
3037        assert_eq!(selection.tail(), 5);
3038    }
3039
3040    #[gpui::test]
3041    fn test_word_selection_drag(cx: &mut TestAppContext) {
3042        let rendered = render_markdown("Hello world test", cx);
3043
3044        // Start with a simulated double-click on "world" (index 6-10)
3045        let word_range = rendered.surrounding_word_range(7); // Click on 'o' in "world"
3046        let mut selection = Selection {
3047            start: word_range.start,
3048            end: word_range.end,
3049            reversed: false,
3050            pending: true,
3051            mode: SelectMode::Word(word_range),
3052        };
3053
3054        // Drag forward to "test" - should expand selection to include "test"
3055        selection.set_head(13, &rendered); // Index in "test"
3056        assert_eq!(selection.start, 6); // Start of "world"
3057        assert_eq!(selection.end, 16); // End of "test"
3058        assert!(!selection.reversed);
3059        let selected_text = rendered.text_for_range(selection.start..selection.end);
3060        assert_eq!(selected_text, "world test");
3061
3062        // Drag backward to "Hello" - should expand selection to include "Hello"
3063        selection.set_head(2, &rendered); // Index in "Hello"
3064        assert_eq!(selection.start, 0); // Start of "Hello"
3065        assert_eq!(selection.end, 11); // End of "world" (original selection)
3066        assert!(selection.reversed);
3067        let selected_text = rendered.text_for_range(selection.start..selection.end);
3068        assert_eq!(selected_text, "Hello world");
3069
3070        // Drag back within original word - should revert to original selection
3071        selection.set_head(8, &rendered); // Back within "world"
3072        assert_eq!(selection.start, 6); // Start of "world"
3073        assert_eq!(selection.end, 11); // End of "world"
3074        assert!(!selection.reversed);
3075        let selected_text = rendered.text_for_range(selection.start..selection.end);
3076        assert_eq!(selected_text, "world");
3077    }
3078
3079    #[gpui::test]
3080    fn test_selection_with_markdown_formatting(cx: &mut TestAppContext) {
3081        let rendered = render_markdown(
3082            "This is **bold** text, this is *italic* text, use `code` here",
3083            cx,
3084        );
3085        let word_range = rendered.surrounding_word_range(10); // Inside "bold"
3086        let selected_text = rendered.text_for_range(word_range);
3087        assert_eq!(selected_text, "bold");
3088
3089        let word_range = rendered.surrounding_word_range(32); // Inside "italic"
3090        let selected_text = rendered.text_for_range(word_range);
3091        assert_eq!(selected_text, "italic");
3092
3093        let word_range = rendered.surrounding_word_range(51); // Inside "code"
3094        let selected_text = rendered.text_for_range(word_range);
3095        assert_eq!(selected_text, "code");
3096    }
3097
3098    #[gpui::test]
3099    fn test_table_column_selection(cx: &mut TestAppContext) {
3100        let rendered = render_markdown("| a | b |\n|---|---|\n| c | d |", cx);
3101
3102        assert!(rendered.lines.len() >= 2);
3103        let first_bounds = rendered.lines[0].layout.bounds();
3104        let second_bounds = rendered.lines[1].layout.bounds();
3105
3106        let first_index = match rendered.source_index_for_position(first_bounds.center()) {
3107            Ok(index) | Err(index) => index,
3108        };
3109        let second_index = match rendered.source_index_for_position(second_bounds.center()) {
3110            Ok(index) | Err(index) => index,
3111        };
3112
3113        let first_word = rendered.text_for_range(rendered.surrounding_word_range(first_index));
3114        let second_word = rendered.text_for_range(rendered.surrounding_word_range(second_index));
3115
3116        assert_eq!(first_word, "a");
3117        assert_eq!(second_word, "b");
3118    }
3119
3120    #[test]
3121    fn test_table_checkbox_detection() {
3122        let md = "| Done |\n|------|\n| [x] |\n| [ ] |";
3123        let events = crate::parser::parse_markdown_with_options(md, false).events;
3124
3125        let mut in_table = false;
3126        let mut cell_texts: Vec<String> = Vec::new();
3127        let mut current_cell = String::new();
3128
3129        for (range, event) in &events {
3130            match event {
3131                MarkdownEvent::Start(MarkdownTag::Table(_)) => in_table = true,
3132                MarkdownEvent::End(MarkdownTagEnd::Table) => in_table = false,
3133                MarkdownEvent::Start(MarkdownTag::TableCell) => current_cell.clear(),
3134                MarkdownEvent::End(MarkdownTagEnd::TableCell) => {
3135                    if in_table {
3136                        cell_texts.push(current_cell.clone());
3137                    }
3138                }
3139                MarkdownEvent::Text if in_table => {
3140                    current_cell.push_str(&md[range.clone()]);
3141                }
3142                _ => {}
3143            }
3144        }
3145
3146        let checkbox_cells: Vec<&String> = cell_texts
3147            .iter()
3148            .filter(|t| {
3149                let trimmed = t.trim();
3150                trimmed == "[x]" || trimmed == "[X]" || trimmed == "[ ]"
3151            })
3152            .collect();
3153        assert_eq!(
3154            checkbox_cells.len(),
3155            2,
3156            "Expected 2 checkbox cells, got: {cell_texts:?}"
3157        );
3158        assert_eq!(checkbox_cells[0].trim(), "[x]");
3159        assert_eq!(checkbox_cells[1].trim(), "[ ]");
3160    }
3161
3162    #[gpui::test]
3163    fn test_inline_code_word_selection_excludes_backticks(cx: &mut TestAppContext) {
3164        // Test that double-clicking on inline code selects just the code content,
3165        // not the backticks. This verifies the fix for the bug where selecting
3166        // inline code would include the trailing backtick.
3167        let rendered = render_markdown("use `blah` here", cx);
3168
3169        // Source layout: "use `blah` here"
3170        //                 0123456789...
3171        // The inline code "blah" is at source positions 5-8 (content range 5..9)
3172
3173        // Click inside "blah" - should select just "blah", not "blah`"
3174        let word_range = rendered.surrounding_word_range(6); // 'l' in "blah"
3175
3176        // text_for_range extracts from the rendered text (without backticks), so it
3177        // would return "blah" even with a wrong source range. We check it anyway.
3178        let selected_text = rendered.text_for_range(word_range.clone());
3179        assert_eq!(selected_text, "blah");
3180
3181        // The source range is what matters for copy_as_markdown and selected_text,
3182        // which extract directly from the source. With the bug, this would be 5..10
3183        // which includes the closing backtick at position 9.
3184        assert_eq!(word_range, 5..9);
3185    }
3186
3187    #[gpui::test]
3188    fn test_surrounding_word_range_respects_word_characters(cx: &mut TestAppContext) {
3189        let rendered = render_markdown("foo.bar() baz", cx);
3190
3191        // Double clicking on 'f' in "foo" - should select just "foo"
3192        let word_range = rendered.surrounding_word_range(0);
3193        let selected_text = rendered.text_for_range(word_range);
3194        assert_eq!(selected_text, "foo");
3195
3196        // Double clicking on 'b' in "bar" - should select just "bar"
3197        let word_range = rendered.surrounding_word_range(4);
3198        let selected_text = rendered.text_for_range(word_range);
3199        assert_eq!(selected_text, "bar");
3200
3201        // Double clicking on 'b' in "baz" - should select "baz"
3202        let word_range = rendered.surrounding_word_range(10);
3203        let selected_text = rendered.text_for_range(word_range);
3204        assert_eq!(selected_text, "baz");
3205
3206        // Double clicking selects word characters in code blocks
3207        let javascript_language = Arc::new(Language::new(
3208            LanguageConfig {
3209                name: "JavaScript".into(),
3210                matcher: LanguageMatcher {
3211                    path_suffixes: vec!["js".to_string()],
3212                    ..Default::default()
3213                },
3214                word_characters: ['$', '#'].into_iter().collect(),
3215                ..Default::default()
3216            },
3217            None,
3218        ));
3219
3220        let language_registry = Arc::new(LanguageRegistry::test(cx.executor()));
3221        language_registry.add(javascript_language);
3222
3223        let rendered = render_markdown_with_language_registry(
3224            "```javascript\n$foo #bar\n```",
3225            Some(language_registry),
3226            cx,
3227        );
3228
3229        let word_range = rendered.surrounding_word_range(14);
3230        let selected_text = rendered.text_for_range(word_range);
3231        assert_eq!(selected_text, "$foo");
3232
3233        let word_range = rendered.surrounding_word_range(19);
3234        let selected_text = rendered.text_for_range(word_range);
3235        assert_eq!(selected_text, "#bar");
3236    }
3237
3238    #[gpui::test]
3239    fn test_all_selection(cx: &mut TestAppContext) {
3240        let rendered = render_markdown("Hello world\n\nThis is a test\n\nwith multiple lines", cx);
3241
3242        let total_length = rendered
3243            .lines
3244            .last()
3245            .map(|line| line.source_end)
3246            .unwrap_or(0);
3247
3248        let mut selection = Selection {
3249            start: 0,
3250            end: total_length,
3251            reversed: false,
3252            pending: true,
3253            mode: SelectMode::All,
3254        };
3255
3256        selection.set_head(5, &rendered); // Try to set head in middle
3257        assert_eq!(selection.start, 0);
3258        assert_eq!(selection.end, total_length);
3259        assert!(!selection.reversed);
3260
3261        selection.set_head(25, &rendered); // Try to set head near end
3262        assert_eq!(selection.start, 0);
3263        assert_eq!(selection.end, total_length);
3264        assert!(!selection.reversed);
3265
3266        let selected_text = rendered.text_for_range(selection.start..selection.end);
3267        assert_eq!(
3268            selected_text,
3269            "Hello world\nThis is a test\nwith multiple lines"
3270        );
3271    }
3272
3273    fn nbsp(n: usize) -> String {
3274        "\u{00A0}".repeat(n)
3275    }
3276
3277    #[test]
3278    fn test_escape_plain_text() {
3279        assert_eq!(Markdown::escape("hello world"), "hello world");
3280        assert_eq!(Markdown::escape(""), "");
3281        assert_eq!(Markdown::escape("café ☕ naïve"), "café ☕ naïve");
3282    }
3283
3284    #[test]
3285    fn test_escape_punctuation() {
3286        assert_eq!(Markdown::escape("hello `world`"), r"hello \`world\`");
3287        assert_eq!(Markdown::escape("a|b"), r"a\|b");
3288    }
3289
3290    #[test]
3291    fn test_escape_leading_spaces() {
3292        assert_eq!(Markdown::escape("    hello"), [&nbsp(4), "hello"].concat());
3293        assert_eq!(
3294            Markdown::escape("    | { a: string }"),
3295            [&nbsp(4), r"\| \{ a\: string \}"].concat()
3296        );
3297        assert_eq!(
3298            Markdown::escape("  first\n  second"),
3299            [&nbsp(2), "first\n\n", &nbsp(2), "second"].concat()
3300        );
3301        assert_eq!(Markdown::escape("hello   world"), "hello   world");
3302    }
3303
3304    #[test]
3305    fn test_escape_leading_tabs() {
3306        assert_eq!(Markdown::escape("\thello"), [&nbsp(4), "hello"].concat());
3307        assert_eq!(
3308            Markdown::escape("hello\n\t\tindented"),
3309            ["hello\n\n", &nbsp(8), "indented"].concat()
3310        );
3311        assert_eq!(
3312            Markdown::escape(" \t hello"),
3313            [&nbsp(1 + 4 + 1), "hello"].concat()
3314        );
3315        assert_eq!(Markdown::escape("hello\tworld"), "hello\tworld");
3316    }
3317
3318    #[test]
3319    fn test_escape_newlines() {
3320        assert_eq!(Markdown::escape("a\nb"), "a\n\nb");
3321        assert_eq!(Markdown::escape("a\n\nb"), "a\n\n\n\nb");
3322        assert_eq!(Markdown::escape("\nhello"), "\n\nhello");
3323    }
3324
3325    #[test]
3326    fn test_escape_multiline_diagnostic() {
3327        assert_eq!(
3328            Markdown::escape("    | { a: string }\n    | { b: number }"),
3329            [
3330                &nbsp(4),
3331                r"\| \{ a\: string \}",
3332                "\n\n",
3333                &nbsp(4),
3334                r"\| \{ b\: number \}",
3335            ]
3336            .concat()
3337        );
3338    }
3339
3340    fn has_code_block(markdown: &str) -> bool {
3341        let parsed_data = parse_markdown_with_options(markdown, false);
3342        parsed_data
3343            .events
3344            .iter()
3345            .any(|(_, event)| matches!(event, MarkdownEvent::Start(MarkdownTag::CodeBlock { .. })))
3346    }
3347
3348    #[test]
3349    fn test_escape_output_len_matches_precomputed() {
3350        let cases = [
3351            "",
3352            "hello world",
3353            "hello `world`",
3354            "    hello",
3355            "    | { a: string }",
3356            "\thello",
3357            "hello\n\t\tindented",
3358            " \t hello",
3359            "hello\tworld",
3360            "a\nb",
3361            "a\n\nb",
3362            "\nhello",
3363            "    | { a: string }\n    | { b: number }",
3364            "café ☕ naïve",
3365        ];
3366        for input in cases {
3367            let mut escaper = MarkdownEscaper::new();
3368            let precomputed: usize = input.bytes().map(|b| escaper.next(b).output_len()).sum();
3369
3370            let mut escaper = MarkdownEscaper::new();
3371            let mut output = String::new();
3372            for c in input.chars() {
3373                escaper.next(c as u8).write_to(c, &mut output);
3374            }
3375
3376            assert_eq!(precomputed, output.len(), "length mismatch for {:?}", input);
3377        }
3378    }
3379
3380    #[test]
3381    fn test_escape_prevents_code_block() {
3382        let diagnostic = "    | { a: string }";
3383        assert!(has_code_block(diagnostic));
3384        assert!(!has_code_block(&Markdown::escape(diagnostic)));
3385    }
3386
3387    #[track_caller]
3388    fn assert_mappings(rendered: &RenderedText, expected: Vec<Vec<(usize, usize)>>) {
3389        assert_eq!(rendered.lines.len(), expected.len(), "line count mismatch");
3390        for (line_ix, line_mappings) in expected.into_iter().enumerate() {
3391            let line = &rendered.lines[line_ix];
3392
3393            assert!(
3394                line.source_mappings.windows(2).all(|mappings| {
3395                    mappings[0].source_index < mappings[1].source_index
3396                        && mappings[0].rendered_index < mappings[1].rendered_index
3397                }),
3398                "line {} has duplicate mappings: {:?}",
3399                line_ix,
3400                line.source_mappings
3401            );
3402
3403            for (rendered_ix, source_ix) in line_mappings {
3404                assert_eq!(
3405                    line.source_index_for_rendered_index(rendered_ix),
3406                    source_ix,
3407                    "line {}, rendered_ix {}",
3408                    line_ix,
3409                    rendered_ix
3410                );
3411
3412                assert_eq!(
3413                    line.rendered_index_for_source_index(source_ix),
3414                    rendered_ix,
3415                    "line {}, source_ix {}",
3416                    line_ix,
3417                    source_ix
3418                );
3419            }
3420        }
3421    }
3422}