1 import * as MarkdownIt from 'markdown-it'
2 import MarkdownItEmoji from 'markdown-it-emoji'
3 import { buildVideoLink } from 'src/assets/player/utils'
4 import { Injectable } from '@angular/core'
5 import { HtmlRendererService } from './html-renderer.service'
7 type MarkdownParsers = {
8 textMarkdownIt: MarkdownIt
9 textWithHTMLMarkdownIt: MarkdownIt
11 enhancedMarkdownIt: MarkdownIt
12 enhancedWithHTMLMarkdownIt: MarkdownIt
14 completeMarkdownIt: MarkdownIt
17 type MarkdownConfig = {
23 type MarkdownParserConfigs = {
24 [id in keyof MarkdownParsers]: MarkdownConfig
28 export class MarkdownService {
37 static TEXT_WITH_HTML_RULES = MarkdownService.TEXT_RULES.concat([ 'html_inline', 'html_block' ])
39 static ENHANCED_RULES = MarkdownService.TEXT_RULES.concat([ 'image' ])
40 static ENHANCED_WITH_HTML_RULES = MarkdownService.TEXT_WITH_HTML_RULES.concat([ 'image' ])
42 static COMPLETE_RULES = MarkdownService.ENHANCED_WITH_HTML_RULES.concat([ 'block', 'inline', 'heading', 'paragraph' ])
44 private markdownParsers: MarkdownParsers = {
46 textWithHTMLMarkdownIt: null,
47 enhancedMarkdownIt: null,
48 enhancedWithHTMLMarkdownIt: null,
49 completeMarkdownIt: null
51 private parsersConfig: MarkdownParserConfigs = {
52 textMarkdownIt: { rules: MarkdownService.TEXT_RULES, html: false },
53 textWithHTMLMarkdownIt: { rules: MarkdownService.TEXT_WITH_HTML_RULES, html: true, escape: true },
55 enhancedMarkdownIt: { rules: MarkdownService.ENHANCED_RULES, html: false },
56 enhancedWithHTMLMarkdownIt: { rules: MarkdownService.ENHANCED_WITH_HTML_RULES, html: true, escape: true },
58 completeMarkdownIt: { rules: MarkdownService.COMPLETE_RULES, html: true }
61 constructor (private htmlRenderer: HtmlRendererService) {}
63 textMarkdownToHTML (markdown: string, withHtml = false, withEmoji = false) {
64 if (withHtml) return this.render('textWithHTMLMarkdownIt', markdown, withEmoji)
66 return this.render('textMarkdownIt', markdown, withEmoji)
69 enhancedMarkdownToHTML (markdown: string, withHtml = false, withEmoji = false) {
70 if (withHtml) return this.render('enhancedWithHTMLMarkdownIt', markdown, withEmoji)
72 return this.render('enhancedMarkdownIt', markdown, withEmoji)
75 completeMarkdownToHTML (markdown: string) {
76 return this.render('completeMarkdownIt', markdown, true)
79 async processVideoTimestamps (html: string) {
80 return html.replace(/((\d{1,2}):)?(\d{1,2}):(\d{1,2})/g, function (str, _, h, m, s) {
81 const t = (3600 * +(h || 0)) + (60 * +(m || 0)) + (+(s || 0))
82 const url = buildVideoLink({ startTime: t })
83 return `<a class="video-timestamp" href="${url}">${str}</a>`
87 private async render (name: keyof MarkdownParsers, markdown: string, withEmoji = false) {
88 if (!markdown) return ''
90 const config = this.parsersConfig[ name ]
91 if (!this.markdownParsers[ name ]) {
92 this.markdownParsers[ name ] = await this.createMarkdownIt(config)
95 this.markdownParsers[ name ].use(MarkdownItEmoji)
99 let html = this.markdownParsers[ name ].render(markdown)
100 html = this.avoidTruncatedTags(html)
102 if (config.escape) return this.htmlRenderer.toSafeHtml(html)
107 private async createMarkdownIt (config: MarkdownConfig) {
108 // FIXME: import('...') returns a struct module, containing a "default" field
109 const MarkdownItClass: typeof import ('markdown-it') = (await import('markdown-it') as any).default
111 const markdownIt = new MarkdownItClass('zero', { linkify: true, breaks: true, html: config.html })
113 for (const rule of config.rules) {
114 markdownIt.enable(rule)
117 this.setTargetToLinks(markdownIt)
122 private setTargetToLinks (markdownIt: MarkdownIt) {
123 // Snippet from markdown-it documentation: https://github.com/markdown-it/markdown-it/blob/master/docs/architecture.md#renderer
124 const defaultRender = markdownIt.renderer.rules.link_open || function (tokens, idx, options, env, self) {
125 return self.renderToken(tokens, idx, options)
128 markdownIt.renderer.rules.link_open = function (tokens, index, options, env, self) {
129 const token = tokens[index]
131 const targetIndex = token.attrIndex('target')
132 if (targetIndex < 0) token.attrPush([ 'target', '_blank' ])
133 else token.attrs[targetIndex][1] = '_blank'
135 const relIndex = token.attrIndex('rel')
136 if (relIndex < 0) token.attrPush([ 'rel', 'noopener noreferrer' ])
137 else token.attrs[relIndex][1] = 'noopener noreferrer'
139 // pass token to default renderer.
140 return defaultRender(tokens, index, options, env, self)
144 private avoidTruncatedTags (html: string) {
145 return html.replace(/\*\*?([^*]+)$/, '$1')
146 .replace(/<a[^>]+>([^<]+)<\/a>\s*...((<\/p>)|(<\/li>)|(<\/strong>))?$/mi, '$1...')
147 .replace(/\[[^\]]+\]\(([^\)]+)$/m, '$1')
148 .replace(/\s?\[[^\]]+\]?[.]{3}<\/p>$/m, '...</p>')