447 lines
18 KiB
Rust
447 lines
18 KiB
Rust
//! An HTML renderer that takes an iterator of [`Event`]s and emits HTML.
|
|
|
|
use crate::Alignment;
|
|
use crate::Container;
|
|
use crate::Event;
|
|
use crate::LinkType;
|
|
use crate::ListKind;
|
|
use crate::OrderedListNumbering::*;
|
|
use crate::Render;
|
|
use crate::SpanLinkType;
|
|
|
|
enum Raw {
|
|
None,
|
|
Html,
|
|
Other,
|
|
}
|
|
|
|
pub struct Renderer {
|
|
raw: Raw,
|
|
img_alt_text: usize,
|
|
list_tightness: Vec<bool>,
|
|
encountered_footnote: bool,
|
|
footnote_number: Option<std::num::NonZeroUsize>,
|
|
first_line: bool,
|
|
close_para: bool,
|
|
}
|
|
|
|
impl Default for Renderer {
|
|
fn default() -> Self {
|
|
Self {
|
|
raw: Raw::None,
|
|
img_alt_text: 0,
|
|
list_tightness: Vec::new(),
|
|
encountered_footnote: false,
|
|
footnote_number: None,
|
|
first_line: true,
|
|
close_para: false,
|
|
}
|
|
}
|
|
}
|
|
|
|
impl Render for Renderer {
|
|
fn render_event<'s, W>(&mut self, e: &Event<'s>, mut out: W) -> std::fmt::Result
|
|
where
|
|
W: std::fmt::Write,
|
|
{
|
|
if matches!(&e, Event::Blankline | Event::Escape) {
|
|
return Ok(());
|
|
}
|
|
|
|
let close_para = self.close_para;
|
|
if close_para {
|
|
self.close_para = false;
|
|
if !matches!(&e, Event::End(Container::Footnote { .. })) {
|
|
// no need to add href before para close
|
|
out.write_str("</p>")?;
|
|
}
|
|
}
|
|
|
|
match e {
|
|
Event::Start(c, attrs) => {
|
|
if c.is_block() && !self.first_line {
|
|
out.write_char('\n')?;
|
|
}
|
|
if self.img_alt_text > 0 && !matches!(c, Container::Image(..)) {
|
|
return Ok(());
|
|
}
|
|
match &c {
|
|
Container::Blockquote => out.write_str("<blockquote")?,
|
|
Container::List { kind, tight } => {
|
|
self.list_tightness.push(*tight);
|
|
match kind {
|
|
ListKind::Unordered | ListKind::Task => out.write_str("<ul")?,
|
|
ListKind::Ordered {
|
|
numbering, start, ..
|
|
} => {
|
|
out.write_str("<ol")?;
|
|
if *start > 1 {
|
|
write!(out, r#" start="{}""#, start)?;
|
|
}
|
|
if let Some(ty) = match numbering {
|
|
Decimal => None,
|
|
AlphaLower => Some('a'),
|
|
AlphaUpper => Some('A'),
|
|
RomanLower => Some('i'),
|
|
RomanUpper => Some('I'),
|
|
} {
|
|
write!(out, r#" type="{}""#, ty)?;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
Container::ListItem | Container::TaskListItem { .. } => {
|
|
out.write_str("<li")?;
|
|
}
|
|
Container::DescriptionList => out.write_str("<dl")?,
|
|
Container::DescriptionDetails => out.write_str("<dd")?,
|
|
Container::Footnote { number, .. } => {
|
|
assert!(self.footnote_number.is_none());
|
|
self.footnote_number = Some((*number).try_into().unwrap());
|
|
if !self.encountered_footnote {
|
|
self.encountered_footnote = true;
|
|
out.write_str("<section role=\"doc-endnotes\">\n<hr>\n<ol>\n")?;
|
|
}
|
|
write!(out, "<li id=\"fn{}\">", number)?;
|
|
return Ok(());
|
|
}
|
|
Container::Table => out.write_str("<table")?,
|
|
Container::TableRow { .. } => out.write_str("<tr")?,
|
|
Container::Section { .. } => out.write_str("<section")?,
|
|
Container::Div { .. } => out.write_str("<div")?,
|
|
Container::Paragraph => {
|
|
if matches!(self.list_tightness.last(), Some(true)) {
|
|
return Ok(());
|
|
}
|
|
out.write_str("<p")?;
|
|
}
|
|
Container::Heading { level, .. } => write!(out, "<h{}", level)?,
|
|
Container::TableCell { head: false, .. } => out.write_str("<td")?,
|
|
Container::TableCell { head: true, .. } => out.write_str("<th")?,
|
|
Container::Caption => out.write_str("<caption")?,
|
|
Container::DescriptionTerm => out.write_str("<dt")?,
|
|
Container::CodeBlock { .. } => out.write_str("<pre")?,
|
|
Container::Span | Container::Math { .. } => out.write_str("<span")?,
|
|
Container::Link(dst, ty) => {
|
|
if matches!(ty, LinkType::Span(SpanLinkType::Unresolved)) {
|
|
out.write_str("<a")?;
|
|
} else {
|
|
out.write_str(r#"<a href=""#)?;
|
|
if matches!(ty, LinkType::Email) {
|
|
out.write_str("mailto:")?;
|
|
}
|
|
write_attr(dst, &mut out)?;
|
|
out.write_char('"')?;
|
|
}
|
|
}
|
|
Container::Image(..) => {
|
|
self.img_alt_text += 1;
|
|
if self.img_alt_text == 1 {
|
|
out.write_str("<img")?;
|
|
} else {
|
|
return Ok(());
|
|
}
|
|
}
|
|
Container::Verbatim => out.write_str("<code")?,
|
|
Container::RawBlock { format } | Container::RawInline { format } => {
|
|
self.raw = if format == &"html" {
|
|
Raw::Html
|
|
} else {
|
|
Raw::Other
|
|
};
|
|
return Ok(());
|
|
}
|
|
Container::Subscript => out.write_str("<sub")?,
|
|
Container::Superscript => out.write_str("<sup")?,
|
|
Container::Insert => out.write_str("<ins")?,
|
|
Container::Delete => out.write_str("<del")?,
|
|
Container::Strong => out.write_str("<strong")?,
|
|
Container::Emphasis => out.write_str("<em")?,
|
|
Container::Mark => out.write_str("<mark")?,
|
|
}
|
|
|
|
for (a, v) in attrs.iter().filter(|(a, _)| *a != "class") {
|
|
write!(out, r#" {}=""#, a)?;
|
|
v.parts().try_for_each(|part| write_attr(part, &mut out))?;
|
|
out.write_char('"')?;
|
|
}
|
|
|
|
if let Container::Heading {
|
|
id,
|
|
has_section: false,
|
|
..
|
|
}
|
|
| Container::Section { id } = &c
|
|
{
|
|
if !attrs.iter().any(|(a, _)| a == "id") {
|
|
out.write_str(r#" id=""#)?;
|
|
write_attr(id, &mut out)?;
|
|
out.write_char('"')?;
|
|
}
|
|
}
|
|
|
|
if attrs.iter().any(|(a, _)| a == "class")
|
|
|| matches!(
|
|
c,
|
|
Container::Div { class: Some(_) }
|
|
| Container::Math { .. }
|
|
| Container::List {
|
|
kind: ListKind::Task,
|
|
..
|
|
}
|
|
| Container::TaskListItem { .. }
|
|
)
|
|
{
|
|
out.write_str(r#" class=""#)?;
|
|
let mut first_written = false;
|
|
if let Some(cls) = match c {
|
|
Container::List {
|
|
kind: ListKind::Task,
|
|
..
|
|
} => Some("task-list"),
|
|
Container::TaskListItem { checked: false } => Some("unchecked"),
|
|
Container::TaskListItem { checked: true } => Some("checked"),
|
|
Container::Math { display: false } => Some("math inline"),
|
|
Container::Math { display: true } => Some("math display"),
|
|
_ => None,
|
|
} {
|
|
first_written = true;
|
|
out.write_str(cls)?;
|
|
}
|
|
for cls in attrs
|
|
.iter()
|
|
.filter(|(a, _)| a == &"class")
|
|
.map(|(_, cls)| cls)
|
|
{
|
|
if first_written {
|
|
out.write_char(' ')?;
|
|
}
|
|
first_written = true;
|
|
cls.parts()
|
|
.try_for_each(|part| write_attr(part, &mut out))?;
|
|
}
|
|
// div class goes after classes from attrs
|
|
if let Container::Div { class: Some(cls) } = c {
|
|
if first_written {
|
|
out.write_char(' ')?;
|
|
}
|
|
out.write_str(cls)?;
|
|
}
|
|
out.write_char('"')?;
|
|
}
|
|
|
|
match c {
|
|
Container::TableCell { alignment, .. }
|
|
if !matches!(alignment, Alignment::Unspecified) =>
|
|
{
|
|
let a = match alignment {
|
|
Alignment::Unspecified => unreachable!(),
|
|
Alignment::Left => "left",
|
|
Alignment::Center => "center",
|
|
Alignment::Right => "right",
|
|
};
|
|
write!(out, r#" style="text-align: {};">"#, a)?;
|
|
}
|
|
Container::CodeBlock { lang } => {
|
|
if let Some(l) = lang {
|
|
out.write_str(r#"><code class="language-"#)?;
|
|
write_attr(l, &mut out)?;
|
|
out.write_str(r#"">"#)?;
|
|
} else {
|
|
out.write_str("><code>")?;
|
|
}
|
|
}
|
|
Container::Image(..) => {
|
|
if self.img_alt_text == 1 {
|
|
out.write_str(r#" alt=""#)?;
|
|
}
|
|
}
|
|
Container::Math { display } => {
|
|
out.write_str(if *display { r#">\["# } else { r#">\("# })?;
|
|
}
|
|
_ => out.write_char('>')?,
|
|
}
|
|
}
|
|
Event::End(c) => {
|
|
if c.is_block_container() && !matches!(c, Container::Footnote { .. }) {
|
|
out.write_char('\n')?;
|
|
}
|
|
if self.img_alt_text > 0 && !matches!(c, Container::Image(..)) {
|
|
return Ok(());
|
|
}
|
|
match c {
|
|
Container::Blockquote => out.write_str("</blockquote>")?,
|
|
Container::List {
|
|
kind: ListKind::Unordered | ListKind::Task,
|
|
..
|
|
} => {
|
|
self.list_tightness.pop();
|
|
out.write_str("</ul>")?;
|
|
}
|
|
Container::List {
|
|
kind: ListKind::Ordered { .. },
|
|
..
|
|
} => out.write_str("</ol>")?,
|
|
Container::ListItem | Container::TaskListItem { .. } => {
|
|
out.write_str("</li>")?;
|
|
}
|
|
Container::DescriptionList => out.write_str("</dl>")?,
|
|
Container::DescriptionDetails => out.write_str("</dd>")?,
|
|
Container::Footnote { number, .. } => {
|
|
if !close_para {
|
|
// create a new paragraph
|
|
out.write_str("\n<p>")?;
|
|
}
|
|
write!(
|
|
out,
|
|
r##"<a href="#fnref{}" role="doc-backlink">↩︎︎</a></p>"##,
|
|
number,
|
|
)?;
|
|
out.write_str("\n</li>")?;
|
|
self.footnote_number = None;
|
|
}
|
|
Container::Table => out.write_str("</table>")?,
|
|
Container::TableRow { .. } => out.write_str("</tr>")?,
|
|
Container::Section { .. } => out.write_str("</section>")?,
|
|
Container::Div { .. } => out.write_str("</div>")?,
|
|
Container::Paragraph => {
|
|
if matches!(self.list_tightness.last(), Some(true)) {
|
|
return Ok(());
|
|
}
|
|
if self.footnote_number.is_none() {
|
|
out.write_str("</p>")?;
|
|
} else {
|
|
self.close_para = true;
|
|
}
|
|
}
|
|
Container::Heading { level, .. } => write!(out, "</h{}>", level)?,
|
|
Container::TableCell { head: false, .. } => out.write_str("</td>")?,
|
|
Container::TableCell { head: true, .. } => out.write_str("</th>")?,
|
|
Container::Caption => out.write_str("</caption>")?,
|
|
Container::DescriptionTerm => out.write_str("</dt>")?,
|
|
Container::CodeBlock { .. } => out.write_str("</code></pre>")?,
|
|
Container::Span => out.write_str("</span>")?,
|
|
Container::Link(..) => out.write_str("</a>")?,
|
|
Container::Image(src, ..) => {
|
|
if self.img_alt_text == 1 {
|
|
if !src.is_empty() {
|
|
out.write_str(r#"" src=""#)?;
|
|
write_attr(src, &mut out)?;
|
|
}
|
|
out.write_str(r#"">"#)?;
|
|
}
|
|
self.img_alt_text -= 1;
|
|
}
|
|
Container::Verbatim => out.write_str("</code>")?,
|
|
Container::Math { display } => {
|
|
out.write_str(if *display {
|
|
r#"\]</span>"#
|
|
} else {
|
|
r#"\)</span>"#
|
|
})?;
|
|
}
|
|
Container::RawBlock { .. } | Container::RawInline { .. } => {
|
|
self.raw = Raw::None;
|
|
}
|
|
Container::Subscript => out.write_str("</sub>")?,
|
|
Container::Superscript => out.write_str("</sup>")?,
|
|
Container::Insert => out.write_str("</ins>")?,
|
|
Container::Delete => out.write_str("</del>")?,
|
|
Container::Strong => out.write_str("</strong>")?,
|
|
Container::Emphasis => out.write_str("</em>")?,
|
|
Container::Mark => out.write_str("</mark>")?,
|
|
}
|
|
}
|
|
Event::Str(s) => match self.raw {
|
|
Raw::None if self.img_alt_text > 0 => write_attr(s, &mut out)?,
|
|
Raw::None => write_text(s, &mut out)?,
|
|
Raw::Html => out.write_str(s)?,
|
|
Raw::Other => {}
|
|
},
|
|
Event::FootnoteReference(_tag, number) => {
|
|
if self.img_alt_text == 0 {
|
|
write!(
|
|
out,
|
|
r##"<a id="fnref{}" href="#fn{}" role="doc-noteref"><sup>{}</sup></a>"##,
|
|
number, number, number
|
|
)?;
|
|
}
|
|
}
|
|
Event::Symbol(sym) => write!(out, ":{}:", sym)?,
|
|
Event::LeftSingleQuote => out.write_str("‘")?,
|
|
Event::RightSingleQuote => out.write_str("’")?,
|
|
Event::LeftDoubleQuote => out.write_str("“")?,
|
|
Event::RightDoubleQuote => out.write_str("”")?,
|
|
Event::Ellipsis => out.write_str("…")?,
|
|
Event::EnDash => out.write_str("–")?,
|
|
Event::EmDash => out.write_str("—")?,
|
|
Event::NonBreakingSpace => out.write_str(" ")?,
|
|
Event::Hardbreak => out.write_str("<br>\n")?,
|
|
Event::Softbreak => out.write_char('\n')?,
|
|
Event::Escape | Event::Blankline => unreachable!("filtered out"),
|
|
Event::ThematicBreak(attrs) => {
|
|
out.write_str("\n<hr")?;
|
|
for (a, v) in attrs.iter() {
|
|
write!(out, r#" {}=""#, a)?;
|
|
v.parts().try_for_each(|part| write_attr(part, &mut out))?;
|
|
out.write_char('"')?;
|
|
}
|
|
out.write_str(">")?;
|
|
}
|
|
}
|
|
self.first_line = false;
|
|
|
|
Ok(())
|
|
}
|
|
|
|
fn render_epilogue<W>(&mut self, mut out: W) -> std::fmt::Result
|
|
where
|
|
W: std::fmt::Write,
|
|
{
|
|
if self.encountered_footnote {
|
|
out.write_str("\n</ol>\n</section>")?;
|
|
}
|
|
out.write_char('\n')?;
|
|
|
|
Ok(())
|
|
}
|
|
}
|
|
|
|
fn write_text<W>(s: &str, out: W) -> std::fmt::Result
|
|
where
|
|
W: std::fmt::Write,
|
|
{
|
|
write_escape(s, false, out)
|
|
}
|
|
|
|
fn write_attr<W>(s: &str, out: W) -> std::fmt::Result
|
|
where
|
|
W: std::fmt::Write,
|
|
{
|
|
write_escape(s, true, out)
|
|
}
|
|
|
|
fn write_escape<W>(mut s: &str, escape_quotes: bool, mut out: W) -> std::fmt::Result
|
|
where
|
|
W: std::fmt::Write,
|
|
{
|
|
let mut ent = "";
|
|
while let Some(i) = s.find(|c| {
|
|
match c {
|
|
'<' => Some("<"),
|
|
'>' => Some(">"),
|
|
'&' => Some("&"),
|
|
'"' if escape_quotes => Some("""),
|
|
_ => None,
|
|
}
|
|
.map_or(false, |s| {
|
|
ent = s;
|
|
true
|
|
})
|
|
}) {
|
|
out.write_str(&s[..i])?;
|
|
out.write_str(ent)?;
|
|
s = &s[i + 1..];
|
|
}
|
|
out.write_str(s)
|
|
}
|