HackMD/public/vendor/markdown-it-mathjax.js

120 lines
3.7 KiB
JavaScript

// modified from https://github.com/classeur/markdown-it-mathjax
(function(root, factory) {
if (typeof exports === 'object') {
module.exports = factory()
} else {
root.markdownitMathjax = factory()
}
})(this, function() {
function math(state, silent) {
var startMathPos = state.pos
if (state.src.charCodeAt(startMathPos) !== 0x5C /* \ */) {
return false
}
var match = state.src.slice(++startMathPos).match(/^(?:\\\[|\\\(|begin\{([^}]*)\})/)
if (!match) {
return false
}
startMathPos += match[0].length
var type, endMarker, includeMarkers
if (match[0] === '\\[') {
type = 'display_math'
endMarker = '\\\\]'
} else if (match[0] === '\\(') {
type = 'inline_math'
endMarker = '\\\\)'
} else if (match[1]) {
type = 'math'
endMarker = '\\end{' + match[1] + '}'
includeMarkers = true
}
var endMarkerPos = state.src.indexOf(endMarker, startMathPos)
if (endMarkerPos === -1) {
return false
}
var nextPos = endMarkerPos + endMarker.length
if (!silent) {
var token = state.push(type + '_open', 'span', 1);
token.attrs = [ ['class', 'mathjax raw'] ];
token = state.push(type, '', 0);
token.content = includeMarkers ?
state.src.slice(state.pos, nextPos) : state.src.slice(startMathPos, endMarkerPos)
token = state.push(type + '_close', 'span', -1);
}
state.pos = nextPos
return true
}
function texMath(state, silent) {
var startMathPos = state.pos
if (state.src.charCodeAt(startMathPos) !== 0x24 /* $ */) {
return false
}
// Parse tex math according to http://pandoc.org/README.html#math
var endMarker = '$'
var afterStartMarker = state.src.charCodeAt(++startMathPos)
if (afterStartMarker === 0x24 /* $ */) {
endMarker = '$$'
if (state.src.charCodeAt(++startMathPos) === 0x24 /* $ */) {
// 3 markers are too much
return false
}
} else {
// Skip if opening $ is succeeded by a space character
if (afterStartMarker === 0x20 /* space */ || afterStartMarker === 0x09 /* \t */ || afterStartMarker === 0x0a /* \n */) {
return false
}
}
var endMarkerPos = state.src.indexOf(endMarker, startMathPos)
if (endMarkerPos === -1) {
return false
}
if (state.src.charCodeAt(endMarkerPos - 1) === 0x5C /* \ */) {
return false
}
var nextPos = endMarkerPos + endMarker.length
if (endMarker.length === 1) {
// Skip if $ is preceded by a space character
var beforeEndMarker = state.src.charCodeAt(endMarkerPos - 1)
if (beforeEndMarker === 0x20 /* space */ || beforeEndMarker === 0x09 /* \t */ || beforeEndMarker === 0x0a /* \n */) {
return false
}
// Skip if closing $ is succeeded by a digit (eg $5 $10 ...)
var suffix = state.src.charCodeAt(nextPos)
if (suffix >= 0x30 && suffix < 0x3A) {
return false
}
}
if (!silent) {
var type = endMarker.length === 1 ? 'inline_math' : 'display_math';
var token = state.push(type + '_open', 'span', 1)
token.attrs = [ ['class', 'mathjax raw'] ]
token = state.push(type, '', 0);
token.content = state.src.slice(startMathPos, endMarkerPos);
token = state.push(type + '_close', 'span', -1);
}
state.pos = nextPos
return true
}
function escapeHtml(html) {
return html.replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/\u00a0/g, ' ')
}
return function(md) {
md.inline.ruler.before('escape', 'math', math)
md.inline.ruler.push('texMath', texMath)
md.renderer.rules.math = function(tokens, idx) {
return escapeHtml(tokens[idx].content)
}
md.renderer.rules.inline_math = function(tokens, idx) {
return '\\(' + escapeHtml(tokens[idx].content) + '\\)'
}
md.renderer.rules.display_math = function(tokens, idx) {
return '\\[' + escapeHtml(tokens[idx].content) + '\\]'
}
}
})