forked from Mirrors/elk
361 lines
9.5 KiB
TypeScript
361 lines
9.5 KiB
TypeScript
// @unimport-disable
|
|
import type { mastodon } from 'masto'
|
|
import type { Node } from 'ultrahtml'
|
|
import { DOCUMENT_NODE, ELEMENT_NODE, TEXT_NODE, h, parse, render } from 'ultrahtml'
|
|
import { findAndReplaceEmojisInText } from '@iconify/utils'
|
|
import { emojiRegEx, getEmojiAttributes } from '../config/emojis'
|
|
|
|
export interface ContentParseOptions {
|
|
emojis?: Record<string, mastodon.v1.CustomEmoji>
|
|
markdown?: boolean
|
|
replaceUnicodeEmoji?: boolean
|
|
astTransforms?: Transform[]
|
|
}
|
|
|
|
const sanitizerBasicClasses = filterClasses(/^(h-\S*|p-\S*|u-\S*|dt-\S*|e-\S*|mention|hashtag|ellipsis|invisible)$/u)
|
|
const sanitizer = sanitize({
|
|
// Allow basic elements as seen in https://github.com/mastodon/mastodon/blob/17f79082b098e05b68d6f0d38fabb3ac121879a9/lib/sanitize_ext/sanitize_config.rb
|
|
br: {},
|
|
p: {},
|
|
a: {
|
|
href: filterHref(),
|
|
class: sanitizerBasicClasses,
|
|
rel: set('nofollow noopener noreferrer'),
|
|
target: set('_blank'),
|
|
},
|
|
span: {
|
|
class: sanitizerBasicClasses,
|
|
},
|
|
// Allow elements potentially created for Markdown code blocks above
|
|
pre: {},
|
|
code: {
|
|
class: filterClasses(/^language-\w+$/),
|
|
},
|
|
})
|
|
|
|
const decoder = process.client ? document.createElement('textarea') : null
|
|
export function decodeHtml(text: string) {
|
|
if (!decoder)
|
|
// not available when SSR
|
|
return text
|
|
decoder.innerHTML = text
|
|
return decoder.value
|
|
}
|
|
|
|
/**
|
|
* Parse raw HTML form Mastodon server to AST,
|
|
* with interop of custom emojis and inline Markdown syntax
|
|
*/
|
|
export function parseMastodonHTML(
|
|
html: string,
|
|
options: ContentParseOptions = {},
|
|
) {
|
|
const {
|
|
markdown = true,
|
|
replaceUnicodeEmoji = true,
|
|
} = options
|
|
|
|
if (markdown) {
|
|
// Handle code blocks
|
|
html = html
|
|
.replace(/>(```|~~~)(\w*)([\s\S]+?)\1/g, (_1, _2, lang: string, raw: string) => {
|
|
const code = htmlToText(raw)
|
|
const classes = lang ? ` class="language-${lang}"` : ''
|
|
return `><pre><code${classes}>${code}</code></pre>`
|
|
})
|
|
}
|
|
|
|
// Always sanitize the raw HTML data *after* it has been modified
|
|
const transforms: Transform[] = [
|
|
sanitizer,
|
|
...options.astTransforms || [],
|
|
]
|
|
|
|
if (replaceUnicodeEmoji)
|
|
transforms.push(transformUnicodeEmoji)
|
|
|
|
if (markdown)
|
|
transforms.push(transformMarkdown)
|
|
|
|
transforms.push(replaceCustomEmoji(options.emojis || {}))
|
|
|
|
transforms.push(transformParagraphs)
|
|
|
|
return transformSync(parse(html), transforms)
|
|
}
|
|
|
|
/**
|
|
* Converts raw HTML form Mastodon server to HTML for Tiptap editor
|
|
*/
|
|
export function convertMastodonHTML(html: string, customEmojis: Record<string, mastodon.v1.CustomEmoji> = {}) {
|
|
const tree = parseMastodonHTML(html, {
|
|
emojis: customEmojis,
|
|
markdown: true,
|
|
replaceUnicodeEmoji: false,
|
|
})
|
|
return render(tree)
|
|
}
|
|
|
|
export function htmlToText(html: string) {
|
|
const tree = parse(html)
|
|
return (tree.children as Node[]).map(n => treeToText(n)).join('').trim()
|
|
}
|
|
|
|
export function treeToText(input: Node): string {
|
|
let pre = ''
|
|
let body = ''
|
|
let post = ''
|
|
|
|
if (input.type === TEXT_NODE)
|
|
return decodeHtml(input.value)
|
|
|
|
if (input.name === 'br')
|
|
return '\n'
|
|
|
|
if (['p', 'pre'].includes(input.name))
|
|
pre = '\n'
|
|
|
|
if (input.name === 'code') {
|
|
if (input.parent?.name === 'pre') {
|
|
const lang = input.attributes.class?.replace('language-', '')
|
|
|
|
pre = `\`\`\`${lang || ''}\n`
|
|
post = '\n```'
|
|
}
|
|
else {
|
|
pre = '`'
|
|
post = '`'
|
|
}
|
|
}
|
|
else if (input.name === 'b' || input.name === 'strong') {
|
|
pre = '**'
|
|
post = '**'
|
|
}
|
|
else if (input.name === 'i' || input.name === 'em') {
|
|
pre = '*'
|
|
post = '*'
|
|
}
|
|
else if (input.name === 'del') {
|
|
pre = '~~'
|
|
post = '~~'
|
|
}
|
|
|
|
if ('children' in input)
|
|
body = (input.children as Node[]).map(n => treeToText(n)).join('')
|
|
|
|
if (input.name === 'img') {
|
|
if (input.attributes.class?.includes('custom-emoji'))
|
|
return `:${input.attributes['data-emoji-id']}:`
|
|
if (input.attributes.class?.includes('iconify-emoji'))
|
|
return input.attributes.alt
|
|
}
|
|
|
|
return pre + body + post
|
|
}
|
|
|
|
// A tree transform function takes an ultrahtml Node object and returns
|
|
// new content that will replace the given node in the tree.
|
|
// Returning a null removes the node from the tree.
|
|
// Strings get converted to text nodes.
|
|
// The input node's children have been transformed before the node itself
|
|
// gets transformed.
|
|
type Transform = (node: Node) => (Node | string)[] | Node | string | null
|
|
|
|
// Helpers for transforming (filtering, modifying, ...) a parsed HTML tree
|
|
// by running the given chain of transform functions one-by-one.
|
|
function transformSync(doc: Node, transforms: Transform[]) {
|
|
function visit(node: Node, transform: Transform, isRoot = false) {
|
|
if (Array.isArray(node.children)) {
|
|
const children = [] as (Node | string)[]
|
|
for (let i = 0; i < node.children.length; i++) {
|
|
const result = visit(node.children[i], transform)
|
|
if (Array.isArray(result))
|
|
children.push(...result)
|
|
|
|
else if (result)
|
|
children.push(result)
|
|
}
|
|
|
|
node.children = children.map((value) => {
|
|
if (typeof value === 'string')
|
|
return { type: TEXT_NODE, value, parent: node }
|
|
value.parent = node
|
|
return value
|
|
})
|
|
}
|
|
return isRoot ? node : transform(node)
|
|
}
|
|
|
|
for (const transform of transforms)
|
|
doc = visit(doc, transform, true) as Node
|
|
|
|
return doc
|
|
}
|
|
|
|
// A tree transform for sanitizing elements & their attributes.
|
|
type AttrSanitizers = Record<string, (value: string | undefined) => string | undefined>
|
|
function sanitize(allowedElements: Record<string, AttrSanitizers>): Transform {
|
|
return (node) => {
|
|
if (node.type !== ELEMENT_NODE)
|
|
return node
|
|
|
|
if (!Object.prototype.hasOwnProperty.call(allowedElements, node.name))
|
|
return null
|
|
|
|
const attrSanitizers = allowedElements[node.name]
|
|
const attrs = {} as Record<string, string>
|
|
for (const [name, func] of Object.entries(attrSanitizers)) {
|
|
const value = func(node.attributes[name])
|
|
if (value !== undefined)
|
|
attrs[name] = value
|
|
}
|
|
node.attributes = attrs
|
|
return node
|
|
}
|
|
}
|
|
|
|
function filterClasses(allowed: RegExp) {
|
|
return (c: string | undefined) => {
|
|
if (!c)
|
|
return undefined
|
|
|
|
return c.split(/\s/g).filter(cls => allowed.test(cls)).join(' ')
|
|
}
|
|
}
|
|
|
|
function set(value: string) {
|
|
return () => value
|
|
}
|
|
|
|
function filterHref() {
|
|
const LINK_PROTOCOLS = new Set([
|
|
'http:',
|
|
'https:',
|
|
'dat:',
|
|
'dweb:',
|
|
'ipfs:',
|
|
'ipns:',
|
|
'ssb:',
|
|
'gopher:',
|
|
'xmpp:',
|
|
'magnet:',
|
|
'gemini:',
|
|
])
|
|
|
|
return (href: string | undefined) => {
|
|
if (href === undefined)
|
|
return undefined
|
|
|
|
// Allow relative links
|
|
if (href.startsWith('/') || href.startsWith('.'))
|
|
return href
|
|
|
|
let url
|
|
try {
|
|
url = new URL(href)
|
|
}
|
|
catch (err) {
|
|
if (err instanceof TypeError)
|
|
return undefined
|
|
throw err
|
|
}
|
|
|
|
if (LINK_PROTOCOLS.has(url.protocol))
|
|
return url.toString()
|
|
return '#'
|
|
}
|
|
}
|
|
|
|
function transformUnicodeEmoji(node: Node) {
|
|
if (node.type !== TEXT_NODE)
|
|
return node
|
|
|
|
let start = 0
|
|
|
|
const matches = [] as (string | Node)[]
|
|
findAndReplaceEmojisInText(emojiRegEx, node.value, (match, result) => {
|
|
const attrs = getEmojiAttributes(match)
|
|
matches.push(result.slice(start))
|
|
matches.push(h('img', { src: attrs.src, alt: attrs.alt, class: attrs.class }))
|
|
start = result.length + match.match.length
|
|
return undefined
|
|
})
|
|
if (matches.length === 0)
|
|
return node
|
|
|
|
matches.push(node.value.slice(start))
|
|
return matches.filter(Boolean)
|
|
}
|
|
|
|
function replaceCustomEmoji(customEmojis: Record<string, mastodon.v1.CustomEmoji>): Transform {
|
|
return (node) => {
|
|
if (node.type !== TEXT_NODE)
|
|
return node
|
|
|
|
const split = node.value.split(/:([\w-]+?):/g)
|
|
if (split.length === 1)
|
|
return node
|
|
|
|
return split.map((name, i) => {
|
|
if (i % 2 === 0)
|
|
return name
|
|
|
|
const emoji = customEmojis[name]
|
|
if (!emoji)
|
|
return `:${name}:`
|
|
|
|
return h('img', { 'src': emoji.url, 'alt': `:${name}:`, 'class': 'custom-emoji', 'data-emoji-id': name })
|
|
}).filter(Boolean)
|
|
}
|
|
}
|
|
|
|
const _markdownReplacements: [RegExp, (c: (string | Node)[]) => Node][] = [
|
|
[/\*\*\*(.*?)\*\*\*/g, c => h('b', null, [h('em', null, c)])],
|
|
[/\*\*(.*?)\*\*/g, c => h('b', null, c)],
|
|
[/\*(.*?)\*/g, c => h('em', null, c)],
|
|
[/~~(.*?)~~/g, c => h('del', null, c)],
|
|
[/`([^`]+?)`/g, c => h('code', null, c)],
|
|
]
|
|
|
|
function _markdownProcess(value: string) {
|
|
const results = [] as (string | Node)[]
|
|
|
|
let start = 0
|
|
while (true) {
|
|
let found: { match: RegExpMatchArray; replacer: (c: (string | Node)[]) => Node } | undefined
|
|
|
|
for (const [re, replacer] of _markdownReplacements) {
|
|
re.lastIndex = start
|
|
|
|
const match = re.exec(value)
|
|
if (match) {
|
|
if (!found || match.index < found.match.index!)
|
|
found = { match, replacer }
|
|
}
|
|
}
|
|
|
|
if (!found)
|
|
break
|
|
|
|
results.push(value.slice(start, found.match.index))
|
|
results.push(found.replacer(_markdownProcess(found.match[1])))
|
|
start = found.match.index! + found.match[0].length
|
|
}
|
|
|
|
results.push(value.slice(start))
|
|
return results.filter(Boolean)
|
|
}
|
|
|
|
function transformMarkdown(node: Node) {
|
|
if (node.type !== TEXT_NODE)
|
|
return node
|
|
return _markdownProcess(node.value)
|
|
}
|
|
|
|
function transformParagraphs(node: Node): Node | Node[] {
|
|
// For top level paragraphs, inject an empty <p> to preserve status paragraphs in our editor (except for the last one)
|
|
if (node.parent?.type === DOCUMENT_NODE && node.name === 'p' && node.parent.children.at(-1) !== node)
|
|
return [node, h('p')]
|
|
return node
|
|
}
|