ZIm/crates/rich_text/src/rich_text.rs
2024-01-19 16:59:17 -07:00

336 lines
12 KiB
Rust

use futures::FutureExt;
use gpui::{
AnyElement, ElementId, FontStyle, FontWeight, HighlightStyle, InteractiveText, IntoElement,
SharedString, StyledText, UnderlineStyle, WindowContext,
};
use language::{HighlightId, Language, LanguageRegistry};
use std::{ops::Range, sync::Arc};
use theme::ActiveTheme;
use ui::LinkPreview;
use util::RangeExt;
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum Highlight {
Code,
Id(HighlightId),
Highlight(HighlightStyle),
Mention,
SelfMention,
}
impl From<HighlightStyle> for Highlight {
fn from(style: HighlightStyle) -> Self {
Self::Highlight(style)
}
}
impl From<HighlightId> for Highlight {
fn from(style: HighlightId) -> Self {
Self::Id(style)
}
}
#[derive(Debug, Clone)]
pub struct RichText {
pub text: SharedString,
pub highlights: Vec<(Range<usize>, Highlight)>,
pub link_ranges: Vec<Range<usize>>,
pub link_urls: Arc<[String]>,
}
/// Allows one to specify extra links to the rendered markdown, which can be used
/// for e.g. mentions.
#[derive(Debug)]
pub struct Mention {
pub range: Range<usize>,
pub is_self_mention: bool,
}
impl RichText {
pub fn element(&self, id: ElementId, cx: &mut WindowContext) -> AnyElement {
let theme = cx.theme();
let code_background = theme.colors().surface_background;
InteractiveText::new(
id,
StyledText::new(self.text.clone()).with_highlights(
&cx.text_style(),
self.highlights.iter().map(|(range, highlight)| {
(
range.clone(),
match highlight {
Highlight::Code => HighlightStyle {
background_color: Some(code_background),
..Default::default()
},
Highlight::Id(id) => HighlightStyle {
background_color: Some(code_background),
..id.style(&theme.syntax()).unwrap_or_default()
},
Highlight::Highlight(highlight) => *highlight,
Highlight::Mention => HighlightStyle {
font_weight: Some(FontWeight::BOLD),
..Default::default()
},
Highlight::SelfMention => HighlightStyle {
font_weight: Some(FontWeight::BOLD),
..Default::default()
},
},
)
}),
),
)
.on_click(self.link_ranges.clone(), {
let link_urls = self.link_urls.clone();
move |ix, cx| cx.open_url(&link_urls[ix])
})
.tooltip({
let link_ranges = self.link_ranges.clone();
let link_urls = self.link_urls.clone();
move |idx, cx| {
for (ix, range) in link_ranges.iter().enumerate() {
if range.contains(&idx) {
return Some(LinkPreview::new(&link_urls[ix], cx));
}
}
None
}
})
.into_any_element()
}
}
pub fn render_markdown_mut(
block: &str,
mut mentions: &[Mention],
language_registry: &Arc<LanguageRegistry>,
language: Option<&Arc<Language>>,
text: &mut String,
highlights: &mut Vec<(Range<usize>, Highlight)>,
link_ranges: &mut Vec<Range<usize>>,
link_urls: &mut Vec<String>,
) {
use pulldown_cmark::{CodeBlockKind, Event, Options, Parser, Tag};
let mut bold_depth = 0;
let mut italic_depth = 0;
let mut link_url = None;
let mut current_language = None;
let mut list_stack = Vec::new();
let options = Options::all();
for (event, source_range) in Parser::new_ext(&block, options).into_offset_iter() {
let prev_len = text.len();
match event {
Event::Text(t) => {
if let Some(language) = &current_language {
render_code(text, highlights, t.as_ref(), language);
} else {
while let Some(mention) = mentions.first() {
if !source_range.contains_inclusive(&mention.range) {
break;
}
mentions = &mentions[1..];
let range = (prev_len + mention.range.start - source_range.start)
..(prev_len + mention.range.end - source_range.start);
highlights.push((
range.clone(),
if mention.is_self_mention {
Highlight::SelfMention
} else {
Highlight::Mention
},
));
}
text.push_str(t.as_ref());
let mut style = HighlightStyle::default();
if bold_depth > 0 {
style.font_weight = Some(FontWeight::BOLD);
}
if italic_depth > 0 {
style.font_style = Some(FontStyle::Italic);
}
if let Some(link_url) = link_url.clone() {
link_ranges.push(prev_len..text.len());
link_urls.push(link_url);
style.underline = Some(UnderlineStyle {
thickness: 1.0.into(),
..Default::default()
});
}
if style != HighlightStyle::default() {
let mut new_highlight = true;
if let Some((last_range, last_style)) = highlights.last_mut() {
if last_range.end == prev_len
&& last_style == &Highlight::Highlight(style)
{
last_range.end = text.len();
new_highlight = false;
}
}
if new_highlight {
highlights.push((prev_len..text.len(), Highlight::Highlight(style)));
}
}
}
}
Event::Code(t) => {
text.push_str(t.as_ref());
if link_url.is_some() {
highlights.push((
prev_len..text.len(),
Highlight::Highlight(HighlightStyle {
underline: Some(UnderlineStyle {
thickness: 1.0.into(),
..Default::default()
}),
..Default::default()
}),
));
}
if let Some(link_url) = link_url.clone() {
link_ranges.push(prev_len..text.len());
link_urls.push(link_url);
}
}
Event::Start(tag) => match tag {
Tag::Paragraph => new_paragraph(text, &mut list_stack),
Tag::Heading(_, _, _) => {
new_paragraph(text, &mut list_stack);
bold_depth += 1;
}
Tag::CodeBlock(kind) => {
new_paragraph(text, &mut list_stack);
current_language = if let CodeBlockKind::Fenced(language) = kind {
language_registry
.language_for_name(language.as_ref())
.now_or_never()
.and_then(Result::ok)
} else {
language.cloned()
}
}
Tag::Emphasis => italic_depth += 1,
Tag::Strong => bold_depth += 1,
Tag::Link(_, url, _) => link_url = Some(url.to_string()),
Tag::List(number) => {
list_stack.push((number, false));
}
Tag::Item => {
let len = list_stack.len();
if let Some((list_number, has_content)) = list_stack.last_mut() {
*has_content = false;
if !text.is_empty() && !text.ends_with('\n') {
text.push('\n');
}
for _ in 0..len - 1 {
text.push_str(" ");
}
if let Some(number) = list_number {
text.push_str(&format!("{}. ", number));
*number += 1;
*has_content = false;
} else {
text.push_str("- ");
}
}
}
_ => {}
},
Event::End(tag) => match tag {
Tag::Heading(_, _, _) => bold_depth -= 1,
Tag::CodeBlock(_) => current_language = None,
Tag::Emphasis => italic_depth -= 1,
Tag::Strong => bold_depth -= 1,
Tag::Link(_, _, _) => link_url = None,
Tag::List(_) => drop(list_stack.pop()),
_ => {}
},
Event::HardBreak => text.push('\n'),
Event::SoftBreak => text.push(' '),
_ => {}
}
}
}
pub fn render_markdown(
block: String,
mentions: &[Mention],
language_registry: &Arc<LanguageRegistry>,
language: Option<&Arc<Language>>,
) -> RichText {
let mut text = String::new();
let mut highlights = Vec::new();
let mut link_ranges = Vec::new();
let mut link_urls = Vec::new();
render_markdown_mut(
&block,
mentions,
language_registry,
language,
&mut text,
&mut highlights,
&mut link_ranges,
&mut link_urls,
);
text.truncate(text.trim_end().len());
RichText {
text: SharedString::from(text),
link_urls: link_urls.into(),
link_ranges,
highlights,
}
}
pub fn render_code(
text: &mut String,
highlights: &mut Vec<(Range<usize>, Highlight)>,
content: &str,
language: &Arc<Language>,
) {
let prev_len = text.len();
text.push_str(content);
let mut offset = 0;
for (range, highlight_id) in language.highlight_text(&content.into(), 0..content.len()) {
if range.start > offset {
highlights.push((prev_len + offset..prev_len + range.start, Highlight::Code));
}
highlights.push((
prev_len + range.start..prev_len + range.end,
Highlight::Id(highlight_id),
));
offset = range.end;
}
if offset < content.len() {
highlights.push((prev_len + offset..prev_len + content.len(), Highlight::Code));
}
}
pub fn new_paragraph(text: &mut String, list_stack: &mut Vec<(Option<u64>, bool)>) {
let mut is_subsequent_paragraph_of_list = false;
if let Some((_, has_content)) = list_stack.last_mut() {
if *has_content {
is_subsequent_paragraph_of_list = true;
} else {
*has_content = true;
return;
}
}
if !text.is_empty() {
if !text.ends_with('\n') {
text.push('\n');
}
text.push('\n');
}
for _ in 0..list_stack.len().saturating_sub(1) {
text.push_str(" ");
}
if is_subsequent_paragraph_of_list {
text.push_str(" ");
}
}