|
|
const md = require('markdown-it')
|
|
|
const mdAttrs = require('markdown-it-attrs')
|
|
|
const mdDecorate = require('markdown-it-decorate')
|
|
|
const _ = require('lodash')
|
|
|
const underline = require('./underline')
|
|
|
|
|
|
const quoteStyles = {
|
|
|
Chinese: '””‘’',
|
|
|
English: '“”‘’',
|
|
|
French: ['«\xA0', '\xA0»', '‹\xA0', '\xA0›'],
|
|
|
German: '„“‚‘',
|
|
|
Greek: '«»‘’',
|
|
|
Japanese: '「」「」',
|
|
|
Hungarian: '„”’’',
|
|
|
Polish: '„”‚‘',
|
|
|
Portuguese: '«»‘’',
|
|
|
Russian: '«»„“',
|
|
|
Spanish: '«»‘’',
|
|
|
Swedish: '””’’'
|
|
|
}
|
|
|
|
|
|
// Unicode Private Use Area characters to temporarily replace special
|
|
|
// characters inside math expressions:
|
|
|
// - pipe (|): prevent markdown table parser from interpreting them as cell
|
|
|
// delimiters.
|
|
|
// - ampersand (&): prevent markdown table parser from interpreting them
|
|
|
// as cell delimiters in multiline tables.
|
|
|
const PIPE_PLACEHOLDER = '\uE002'
|
|
|
const AMPERSAND_PLACEHOLDER = '\uE003'
|
|
|
|
|
|
/**
|
|
|
* Replace pipe and ampersand characters inside inline ($...$) and block
|
|
|
* ($$...$$) math expressions with placeholders to prevent markdown table
|
|
|
* parsers from splitting formulas containing | (e.g., |x|) or &
|
|
|
* (e.g., \begin{cases} ... & ... \\ ... \end{cases}).
|
|
|
*/
|
|
|
function protectMathPipes (text) {
|
|
|
let result = ''
|
|
|
let i = 0
|
|
|
while (i < text.length) {
|
|
|
// Check for block math ($$...$$)
|
|
|
if (text.slice(i, i + 2) === '$$') {
|
|
|
const end = text.indexOf('$$', i + 2)
|
|
|
if (end !== -1) {
|
|
|
result += text.slice(i, end + 2)
|
|
|
.replace(/\|/g, PIPE_PLACEHOLDER)
|
|
|
.replace(/&/g, AMPERSAND_PLACEHOLDER)
|
|
|
i = end + 2
|
|
|
continue
|
|
|
}
|
|
|
}
|
|
|
// Check for inline math ($...$)
|
|
|
if (text[i] === '$' && text[i + 1] !== '$') {
|
|
|
const end = text.indexOf('$', i + 1)
|
|
|
if (end !== -1) {
|
|
|
result += text.slice(i, end + 1)
|
|
|
.replace(/\|/g, PIPE_PLACEHOLDER)
|
|
|
.replace(/&/g, AMPERSAND_PLACEHOLDER)
|
|
|
i = end + 1
|
|
|
continue
|
|
|
}
|
|
|
}
|
|
|
result += text[i]
|
|
|
i++
|
|
|
}
|
|
|
return result
|
|
|
}
|
|
|
|
|
|
module.exports = {
|
|
|
async render() {
|
|
|
const mkdown = md({
|
|
|
html: this.config.allowHTML,
|
|
|
breaks: this.config.linebreaks,
|
|
|
linkify: this.config.linkify,
|
|
|
typographer: this.config.typographer,
|
|
|
quotes: _.get(quoteStyles, this.config.quotes, quoteStyles.English),
|
|
|
highlight(str, lang) {
|
|
|
if (lang === 'diagram') {
|
|
|
return `<pre class="diagram">` + Buffer.from(str, 'base64').toString() + `</pre>`
|
|
|
} else {
|
|
|
return `<pre><code class="language-${lang}">${_.escape(str)}</code></pre>`
|
|
|
}
|
|
|
}
|
|
|
})
|
|
|
|
|
|
if (this.config.underline) {
|
|
|
mkdown.use(underline)
|
|
|
}
|
|
|
|
|
|
mkdown.use(mdAttrs, {
|
|
|
allowedAttributes: ['id', 'class', 'target']
|
|
|
})
|
|
|
mkdown.use(mdDecorate)
|
|
|
|
|
|
for (let child of this.children) {
|
|
|
const renderer = require(`../${_.kebabCase(child.key)}/renderer.js`)
|
|
|
await renderer.init(mkdown, child.config)
|
|
|
}
|
|
|
|
|
|
// Protect pipe characters inside math expressions before markdown parsing
|
|
|
const protectedInput = protectMathPipes(this.input)
|
|
|
return mkdown.render(protectedInput)
|
|
|
}
|
|
|
}
|
