HackMD/public/js/reveal-markdown.js
Sheogorath c59b94a37b
Remove the xss library from webpack
We can load the xss functions directly from the library instead of
loading them through the expose loader of webpack, this should simplify
the setup and maybe even improve speed a bit.

Signed-off-by: Sheogorath <sheogorath@shivering-isles.com>
2018-11-10 20:27:07 +01:00

355 lines
12 KiB
JavaScript

/* eslint-env browser, jquery */
import { preventXSS, escapeAttrValue } from './render'
import { md } from './extra'
/**
* The reveal.js markdown plugin. Handles parsing of
* markdown inside of presentations as well as loading
* of external markdown documents.
*/
(function (root, factory) {
if (typeof exports === 'object') {
module.exports = factory()
} else {
// Browser globals (root is window)
root.RevealMarkdown = factory()
root.RevealMarkdown.initialize()
}
}(this, function () {
var DEFAULT_SLIDE_SEPARATOR = '^\r?\n---\r?\n$'
var DEFAULT_NOTES_SEPARATOR = '^note:'
var DEFAULT_ELEMENT_ATTRIBUTES_SEPARATOR = '\\.element\\s*?(.+?)$'
var DEFAULT_SLIDE_ATTRIBUTES_SEPARATOR = '\\.slide:\\s*?(\\S.+?)$'
var SCRIPT_END_PLACEHOLDER = '__SCRIPT_END__'
/**
* Retrieves the markdown contents of a slide section
* element. Normalizes leading tabs/whitespace.
*/
function getMarkdownFromSlide (section) {
var template = section.querySelector('script')
// strip leading whitespace so it isn't evaluated as code
var text = (template || section).textContent
// restore script end tags
text = text.replace(new RegExp(SCRIPT_END_PLACEHOLDER, 'g'), '</script>')
var leadingWs = text.match(/^\n?(\s*)/)[1].length
var leadingTabs = text.match(/^\n?(\t*)/)[1].length
if (leadingTabs > 0) {
text = text.replace(new RegExp('\\n?\\t{' + leadingTabs + '}', 'g'), '\n')
} else if (leadingWs > 1) {
text = text.replace(new RegExp('\\n? {' + leadingWs + '}', 'g'), '\n')
}
return text
}
/**
* Given a markdown slide section element, this will
* return all arguments that aren't related to markdown
* parsing. Used to forward any other user-defined arguments
* to the output markdown slide.
*/
function getForwardedAttributes (section) {
var attributes = section.attributes
var result = []
for (var i = 0, len = attributes.length; i < len; i++) {
var name = attributes[i].name
var value = attributes[i].value
// disregard attributes that are used for markdown loading/parsing
if (/data-(markdown|separator|vertical|notes)/gi.test(name)) continue
if (value) {
result.push(name + '="' + value + '"')
} else {
result.push(name)
}
}
return result.join(' ')
}
/**
* Inspects the given options and fills out default
* values for what's not defined.
*/
function getSlidifyOptions (options) {
options = options || {}
options.separator = options.separator || DEFAULT_SLIDE_SEPARATOR
options.notesSeparator = options.notesSeparator || DEFAULT_NOTES_SEPARATOR
options.attributes = options.attributes || ''
return options
}
/**
* Helper function for constructing a markdown slide.
*/
function createMarkdownSlide (content, options) {
options = getSlidifyOptions(options)
var notesMatch = content.split(new RegExp(options.notesSeparator, 'mgi'))
if (notesMatch.length === 2) {
content = notesMatch[0] + '<aside class="notes" data-markdown>' + notesMatch[1].trim() + '</aside>'
}
// prevent script end tags in the content from interfering
// with parsing
content = content.replace(/<\/script>/g, SCRIPT_END_PLACEHOLDER)
return '<script type="text/template">' + content + '</script>'
}
/**
* Parses a data string into multiple slides based
* on the passed in separator arguments.
*/
function slidify (markdown, options) {
options = getSlidifyOptions(options)
var separatorRegex = new RegExp(options.separator + (options.verticalSeparator ? '|' + options.verticalSeparator : ''), 'mg')
var horizontalSeparatorRegex = new RegExp(options.separator)
var matches
var lastIndex = 0
var isHorizontal
var wasHorizontal = true
var content
var sectionStack = []
// iterate until all blocks between separators are stacked up
while ((matches = separatorRegex.exec(markdown)) !== null) {
// determine direction (horizontal by default)
isHorizontal = horizontalSeparatorRegex.test(matches[0])
if (!isHorizontal && wasHorizontal) {
// create vertical stack
sectionStack.push([])
}
// pluck slide content from markdown input
content = markdown.substring(lastIndex, matches.index)
if (isHorizontal && wasHorizontal) {
// add to horizontal stack
sectionStack.push(content)
} else {
// add to vertical stack
sectionStack[sectionStack.length - 1].push(content)
}
lastIndex = separatorRegex.lastIndex
wasHorizontal = isHorizontal
}
// add the remaining slide
(wasHorizontal ? sectionStack : sectionStack[sectionStack.length - 1]).push(markdown.substring(lastIndex))
var markdownSections = ''
// flatten the hierarchical stack, and insert <section data-markdown> tags
for (var i = 0, len = sectionStack.length; i < len; i++) {
// vertical
if (sectionStack[i] instanceof Array) {
markdownSections += '<section ' + options.attributes + '>'
sectionStack[i].forEach(function (child) {
markdownSections += '<section data-markdown>' + createMarkdownSlide(child, options) + '</section>'
})
markdownSections += '</section>'
} else {
markdownSections += '<section ' + options.attributes + ' data-markdown>' + createMarkdownSlide(sectionStack[i], options) + '</section>'
}
}
return markdownSections
}
/**
* Parses any current data-markdown slides, splits
* multi-slide markdown into separate sections and
* handles loading of external markdown.
*/
function processSlides () {
var sections = document.querySelectorAll('[data-markdown]')
var section
for (var i = 0, len = sections.length; i < len; i++) {
section = sections[i]
if (section.getAttribute('data-markdown').length) {
var xhr = new XMLHttpRequest()
var url = section.getAttribute('data-markdown')
var datacharset = section.getAttribute('data-charset')
// see https://developer.mozilla.org/en-US/docs/Web/API/element.getAttribute#Notes
if (datacharset !== null && datacharset !== '') {
xhr.overrideMimeType('text/html; charset=' + datacharset)
}
xhr.onreadystatechange = function () {
if (xhr.readyState === 4) {
// file protocol yields status code 0 (useful for local debug, mobile applications etc.)
if ((xhr.status >= 200 && xhr.status < 300) || xhr.status === 0) {
section.outerHTML = slidify(xhr.responseText, {
separator: section.getAttribute('data-separator'),
verticalSeparator: section.getAttribute('data-separator-vertical'),
notesSeparator: section.getAttribute('data-separator-notes'),
attributes: getForwardedAttributes(section)
})
} else {
section.outerHTML = '<section data-state="alert">' +
'ERROR: The attempt to fetch ' + url + ' failed with HTTP status ' + xhr.status + '.' +
'Check your browser\'s JavaScript console for more details.' +
'<p>Remember that you need to serve the presentation HTML from a HTTP server.</p>' +
'</section>'
}
}
}
xhr.open('GET', url, false)
try {
xhr.send()
} catch (e) {
alert('Failed to get the Markdown file ' + url + '. Make sure that the presentation and the file are served by a HTTP server and the file can be found there. ' + e)
}
} else if (section.getAttribute('data-separator') || section.getAttribute('data-separator-vertical') || section.getAttribute('data-separator-notes')) {
section.outerHTML = slidify(getMarkdownFromSlide(section), {
separator: section.getAttribute('data-separator'),
verticalSeparator: section.getAttribute('data-separator-vertical'),
notesSeparator: section.getAttribute('data-separator-notes'),
attributes: getForwardedAttributes(section)
})
} else {
section.innerHTML = createMarkdownSlide(getMarkdownFromSlide(section))
}
}
}
/**
* Check if a node value has the attributes pattern.
* If yes, extract it and add that value as one or several attributes
* the the terget element.
*
* You need Cache Killer on Chrome to see the effect on any FOM transformation
* directly on refresh (F5)
* http://stackoverflow.com/questions/5690269/disabling-chrome-cache-for-website-development/7000899#answer-11786277
*/
function addAttributeInElement (node, elementTarget, separator) {
var mardownClassesInElementsRegex = new RegExp(separator, 'mg')
var mardownClassRegex = new RegExp('([^"= ]+?)="([^"=]+?)"', 'mg')
var nodeValue = node.nodeValue
var matches
var matchesClass
if ((matches = mardownClassesInElementsRegex.exec(nodeValue))) {
var classes = matches[1]
nodeValue = nodeValue.substring(0, matches.index) + nodeValue.substring(mardownClassesInElementsRegex.lastIndex)
node.nodeValue = nodeValue
while ((matchesClass = mardownClassRegex.exec(classes))) {
var name = matchesClass[1]
var value = matchesClass[2]
if (name.substr(0, 5) === 'data-' || window.whiteListAttr.indexOf(name) !== -1) { elementTarget.setAttribute(name, escapeAttrValue(value)) }
}
return true
}
return false
}
/**
* Add attributes to the parent element of a text node,
* or the element of an attribute node.
*/
function addAttributes (section, element, previousElement, separatorElementAttributes, separatorSectionAttributes) {
if (element != null && element.childNodes !== undefined && element.childNodes.length > 0) {
var previousParentElement = element
for (var i = 0; i < element.childNodes.length; i++) {
var childElement = element.childNodes[i]
if (i > 0) {
let j = i - 1
while (j >= 0) {
var aPreviousChildElement = element.childNodes[j]
if (typeof aPreviousChildElement.setAttribute === 'function' && aPreviousChildElement.tagName !== 'BR') {
previousParentElement = aPreviousChildElement
break
}
j = j - 1
}
}
var parentSection = section
if (childElement.nodeName === 'section') {
parentSection = childElement
previousParentElement = childElement
}
if (typeof childElement.setAttribute === 'function' || childElement.nodeType === Node.COMMENT_NODE) {
addAttributes(parentSection, childElement, previousParentElement, separatorElementAttributes, separatorSectionAttributes)
}
}
}
if (element.nodeType === Node.COMMENT_NODE) {
if (addAttributeInElement(element, previousElement, separatorElementAttributes) === false) {
addAttributeInElement(element, section, separatorSectionAttributes)
}
}
}
/**
* Converts any current data-markdown slides in the
* DOM to HTML.
*/
function convertSlides () {
var sections = document.querySelectorAll('[data-markdown]')
for (var i = 0, len = sections.length; i < len; i++) {
var section = sections[i]
// Only parse the same slide once
if (!section.getAttribute('data-markdown-parsed')) {
section.setAttribute('data-markdown-parsed', true)
var notes = section.querySelector('aside.notes')
var markdown = getMarkdownFromSlide(section)
markdown = markdown.replace(/&lt;/g, '<').replace(/&gt;/g, '>')
var rendered = md.render(markdown)
rendered = preventXSS(rendered)
var result = window.postProcess(rendered)
section.innerHTML = result[0].outerHTML
addAttributes(section, section, null, section.getAttribute('data-element-attributes') ||
section.parentNode.getAttribute('data-element-attributes') ||
DEFAULT_ELEMENT_ATTRIBUTES_SEPARATOR,
section.getAttribute('data-attributes') ||
section.parentNode.getAttribute('data-attributes') ||
DEFAULT_SLIDE_ATTRIBUTES_SEPARATOR)
// If there were notes, we need to re-add them after
// having overwritten the section's HTML
if (notes) {
section.appendChild(notes)
}
}
}
}
// API
return {
initialize: function () {
processSlides()
convertSlides()
},
// TODO: Do these belong in the API?
processSlides: processSlides,
convertSlides: convertSlides,
slidify: slidify
}
}))