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Diffstat (limited to 'helix-term/src/ui/markdown.rs')
| -rw-r--r-- | helix-term/src/ui/markdown.rs | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/helix-term/src/ui/markdown.rs b/helix-term/src/ui/markdown.rs new file mode 100644 index 00000000..8456ef74 --- /dev/null +++ b/helix-term/src/ui/markdown.rs @@ -0,0 +1,137 @@ +use crate::compositor::{Component, Compositor, Context, EventResult}; +use crossterm::event::{Event, KeyCode, KeyEvent, KeyModifiers}; +use tui::buffer::Buffer as Surface; +use tui::{ + layout::Rect, + style::{Color, Style}, + text::Text, +}; + +use std::borrow::Cow; + +use helix_core::Position; +use helix_view::Editor; + +pub struct Markdown { + contents: String, +} + +impl Markdown { + pub fn new(contents: String) -> Self { + Self { contents } + } +} +impl Component for Markdown { + fn render(&self, area: Rect, surface: &mut Surface, cx: &mut Context) { + use tui::widgets::{Paragraph, Widget, Wrap}; + + use pulldown_cmark::{CodeBlockKind, CowStr, Event, Options, Parser, Tag}; + use tui::text::{Span, Spans, Text}; + + // 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(&self.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.into(), + 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 => { + // whenever paragraph closes, new line + let spans = std::mem::replace(&mut spans, Vec::new()); + lines.push(Spans::from(spans)); + lines.push(Spans::default()); + } + Tag::CodeBlock(CodeBlockKind::Fenced(_)) => { + let spans = std::mem::replace(&mut spans, Vec::new()); + lines.push(Spans::from(spans)); + } + _ => (), + } + } + Event::Text(text) => { + if let Some(Tag::CodeBlock(CodeBlockKind::Fenced(_))) = tags.last() { + for line in text.lines() { + let mut 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 + _ => (), + } + // build up a vec of Paragraph tui widgets + } + + if !spans.is_empty() { + lines.push(Spans::from(spans)); + } + + let contents = Text::from(lines); + + let par = Paragraph::new(contents).wrap(Wrap { trim: false }); + // .scroll(x, y) offsets + + // padding on all sides + let area = Rect::new(area.x + 1, area.y + 1, area.width - 2, area.height - 2); + par.render(area, surface); + } + + fn size_hint(&self, area: Rect) -> Option<(usize, usize)> { + let contents = tui::text::Text::from(self.contents.clone()); + Some((contents.width(), contents.height())) + } +} + +#[cfg(test)] +mod test { + use super::*; + + #[test] + fn it_works() {} +} |