+use pulldown_cmark::{CodeBlockKind, CowStr, Event, Options, Parser, Tag};

+ syntax::{self, HighlightEvent, Syntax},

+ Rope,

+ graphics::{Color, Margin, Rect, Style},

+ config_loader: Arc<syntax::Loader>,

+ pub fn new(contents: String, config_loader: Arc<syntax::Loader>) -> Self {

+}

+fn parse<'a>(

+ contents: &'a str,

+ theme: Option<&Theme>,

+ loader: &syntax::Loader,

+) -> tui::text::Text<'a> {

+ // // also 2021-03-04T16:33:58.553 helix_lsp::transport [INFO] <- {"contents":{"kind":"markdown","value":"\n```rust\ncore::num\n```\n\n```rust\npub const fn saturating_sub(self, rhs:Self) ->Self\n```\n\n---\n\n```rust\n```"},"range":{"end":{"character":61,"line":101},"start":{"character":47,"line":101}}}

+ // let text = "\n```rust\ncore::iter::traits::iterator::Iterator\n```\n\n```rust\nfn collect<B: FromIterator<Self::Item>>(self) -> B\nwhere\n Self: Sized,\n```\n\n---\n\nTransforms an iterator into a collection.\n\n`collect()` can take anything iterable, and turn it into a relevant\ncollection. This is one of the more powerful methods in the standard\nlibrary, used in a variety of contexts.\n\nThe most basic pattern in which `collect()` is used is to turn one\ncollection into another. You take a collection, call [`iter`](https://doc.rust-lang.org/nightly/core/iter/traits/iterator/trait.Iterator.html) on it,\ndo a bunch of transformations, and then `collect()` at the end.\n\n`collect()` can also create instances of types that are not typical\ncollections. For example, a [`String`](https://doc.rust-lang.org/nightly/core/iter/std/string/struct.String.html) can be built from [`char`](type@char)s,\nand an iterator of [`Result<T, E>`](https://doc.rust-lang.org/nightly/core/result/enum.Result.html) items can be collected\ninto `Result<Collection<T>, E>`. See the examples below for more.\n\nBecause `collect()` is so general, it can cause problems with type\ninference. As such, `collect()` is one of the few times you'll see\nthe syntax affectionately known as the 'turbofish': `::<>`. This\nhelps the inference algorithm understand specifically which collection\nyou're trying to collect into.\n\n# Examples\n\nBasic usage:\n\n```rust\nlet a = [1, 2, 3];\n\nlet doubled: Vec<i32> = a.iter()\n .map(|&x| x * 2)\n .collect();\n\nassert_eq!(vec![2, 4, 6], doubled);\n```\n\nNote that we needed the `: Vec<i32>` on the left-hand side. This is because\nwe could collect into, for example, a [`VecDeque<T>`](https://doc.rust-lang.org/nightly/core/iter/std/collections/struct.VecDeque.html) instead:\n\n```rust\nuse std::collections::VecDeque;\n\nlet a = [1, 2, 3];\n\nlet doubled: VecDeque<i32> = a.iter().map(|&x| x * 2).collect();\n\nassert_eq!(2, doubled[0]);\nassert_eq!(4, doubled[1]);\nassert_eq!(6, doubled[2]);\n```\n\nUsing the 'turbofish' instead of annotating `doubled`:\n\n```rust\nlet a = [1, 2, 3];\n\nlet doubled = a.iter().map(|x| x * 2).collect::<Vec<i32>>();\n\nassert_eq!(vec![2, 4, 6], doubled);\n```\n\nBecause `collect()` only cares about what you're collecting into, you can\nstill use a partial type hint, `_`, with the turbofish:\n\n```rust\nlet a = [1, 2, 3];\n\nlet doubled = a.iter().map(|x| x * 2).collect::<Vec<_>>();\n\nassert_eq!(vec![2, 4, 6], doubled);\n```\n\nUsing `collect()` to make a [`String`](https://doc.rust-lang.org/nightly/core/iter/std/string/struct.String.html):\n\n```rust\nlet chars = ['g', 'd', 'k', 'k', 'n'];\n\nlet hello: String = chars.iter()\n .map(|&x| x as u8)\n .map(|x| (x + 1) as char)\n .collect();\n\nassert_eq!(\"hello\", hello);\n```\n\nIf you have a list of [`Result<T, E>`](https://doc.rust-lang.org/nightly/core/result/enum.Result.html)s, you can use `collect()` to\nsee if any of them failed:\n\n```rust\nlet results = [Ok(1), Err(\"nope\"), Ok(3), Err(\"bad\")];\n\nlet result: Result<Vec<_>, &str> = results.iter().cloned().collect();\n\n// gives us the first error\nassert_eq!(Err(\"nope\"), result);\n\nlet results = [Ok(1), Ok(3)];\n\nlet result: Result<Vec<_>, &str> = results.iter().cloned().collect();\n\n// gives us the list of answers\nassert_eq!(Ok(vec![1, 3]), result);\n```";

+ let mut options = Options::empty();

+ options.insert(Options::ENABLE_STRIKETHROUGH);

+ let parser = Parser::new_ext(contents, options);

+ // TODO: if possible, render links as terminal hyperlinks: https://gist.github.com/egmontkob/eb114294efbcd5adb1944c9f3cb5feda

+ let mut tags = Vec::new();

+ let mut spans = Vec::new();

+ let mut lines = Vec::new();

+ fn to_span(text: pulldown_cmark::CowStr) -> Span {

+ use std::ops::Deref;

+ Span::raw::<std::borrow::Cow<_>>(match text {

+ CowStr::Borrowed(s) => s.to_string().into(), // could retain borrow

+ CowStr::Boxed(s) => s.to_string().into(),

+ CowStr::Inlined(s) => s.deref().to_owned().into(),

+ })

+ }

+ let text_style = Style::default().fg(Color::Rgb(164, 160, 232)); // lavender

+ let code_style = Style::default().fg(Color::Rgb(255, 255, 255)); // white

+ let heading_style = Style::default().fg(Color::Rgb(219, 191, 239)); // lilac

+

+ for event in parser {

+ match event {

+ Event::Start(tag) => tags.push(tag),

+ Event::End(tag) => {

+ tags.pop();

+ match tag {

+ Tag::Heading(_) | Tag::Paragraph | Tag::CodeBlock(CodeBlockKind::Fenced(_)) => {

+ // whenever code block or paragraph closes, new line

+ let spans = std::mem::take(&mut spans);

+ if !spans.is_empty() {

+ lines.push(Spans::from(spans));

+ }

+ _ => (),

+ }

+ Event::Text(text) => {

+ // TODO: temp workaround

+ if let Some(Tag::CodeBlock(CodeBlockKind::Fenced(language))) = tags.last() {

+ if let Some(theme) = theme {

+ let rope = Rope::from(text.as_ref());

+ let syntax = loader

+ .language_configuration_for_injection_string(language)

+ .and_then(|config| config.highlight_config(theme.scopes()))

+ .map(|config| Syntax::new(&rope, config));

+

+ if let Some(syntax) = syntax {

+ // if we have a syntax available, highlight_iter and generate spans

+ let mut highlights = Vec::new();

+

+ for event in syntax.highlight_iter(rope.slice(..), None, None, |_| None)

+ {

+ match event.unwrap() {

+ HighlightEvent::HighlightStart(span) => {

+ highlights.push(span);

+ }

+ HighlightEvent::HighlightEnd => {

+ highlights.pop();

+ }

+ HighlightEvent::Source { start, end } => {

+ let style = match highlights.first() {

+ Some(span) => theme.get(&theme.scopes()[span.0]),

+ None => text_style,

+ };

+

+ // TODO: replace tabs with indentation

+

+ let mut slice = &text[start..end];

+ // TODO: do we need to handle all unicode line endings

+ // here, or is just '\n' okay?

+ while let Some(end) = slice.find('\n') {

+ // emit span up to newline

+ let text = &slice[..end];

+ let text = text.replace('\t', " "); // replace tabs

+ let span = Span::styled(text, style);

+ spans.push(span);

+

+ // truncate slice to after newline

+ slice = &slice[end + 1..];

+

+ // make a new line

+ let spans = std::mem::take(&mut spans);

+ lines.push(Spans::from(spans));

+ }

+

+ // if there's anything left, emit it too

+ if !slice.is_empty() {

+ let span =

+ Span::styled(slice.replace('\t', " "), style);

+ spans.push(span);

+ }

+ }

+ }

+ }

+ } else {

+ for line in text.lines() {

+ let span = Span::styled(line.to_string(), code_style);

+ lines.push(Spans::from(span));

+ }

+ for line in text.lines() {

+ let span = Span::styled(line.to_string(), code_style);

+ lines.push(Spans::from(span));

+ }

+ } else if let Some(Tag::Heading(_)) = tags.last() {

+ let mut span = to_span(text);

+ span.style = heading_style;

+ spans.push(span);

+ } else {

+ let mut span = to_span(text);

+ span.style = text_style;

+ spans.push(span);

+ Event::Code(text) | Event::Html(text) => {

+ let mut span = to_span(text);

+ span.style = code_style;

+ spans.push(span);

+ }

+ Event::SoftBreak | Event::HardBreak => {

+ // let spans = std::mem::replace(&mut spans, Vec::new());

+ // lines.push(Spans::from(spans));

+ spans.push(Span::raw(" "));

+ }

+ Event::Rule => {

+ lines.push(Spans::from("---"));

+ lines.push(Spans::default());

+ }

+ // TaskListMarker(bool) true if checked

+ _ => {

+ log::warn!("unhandled markdown event {:?}", event);

+ }

+ // build up a vec of Paragraph tui widgets

+ }

+ if !spans.is_empty() {

+ lines.push(Spans::from(spans));

+ }

+ // if last line is empty, remove it

+ if let Some(line) = lines.last() {

+ if line.0.is_empty() {

+ lines.pop();

+ Text::from(lines)

+}

+ let text = parse(&self.contents, Some(&cx.editor.theme), &self.config_loader);

+ let par = Paragraph::new(text)

+ let margin = Margin {

+ vertical: 1,

+ horizontal: 1,

+ };

+ par.render(area.inner(&margin), surface);

+ if padding >= viewport.1 || padding >= viewport.0 {

+ return None;

+ }

+ let contents = parse(&self.contents, None, &self.config_loader);

+ let max_text_width = (viewport.0 - padding).min(120);

+ let mut text_width = 0;

+ let mut height = padding;

+ for content in contents {

+ height += 1;

+ let content_width = content.width() as u16;

+ if content_width > max_text_width {

+ text_width = max_text_width;

+ height += content_width / max_text_width;

+ } else if content_width > text_width {

+ text_width = content_width;

+ }

+ if height >= viewport.1 {

+ height = viewport.1;

+ break;

+ }

+ }

+ Some((text_width + padding, height))