+import { Injectable } from '@angular/core'
+
+import * as MarkdownIt from 'markdown-it'
+
+@Injectable()
+export class MarkdownService {
+ private markdownIt: MarkdownIt.MarkdownIt
+
+ constructor () {
+ this.markdownIt = new MarkdownIt('zero', { linkify: true })
+ .enable('linkify')
+ .enable('autolink')
+ .enable('emphasis')
+ .enable('link')
+ .enable('newline')
+
+ // Snippet from markdown-it documentation: https://github.com/markdown-it/markdown-it/blob/master/docs/architecture.md#renderer
+ const defaultRender = this.markdownIt.renderer.rules.link_open || function (tokens, idx, options, env, self) {
+ return self.renderToken(tokens, idx, options)
+ }
+
+ this.markdownIt.renderer.rules.link_open = function (tokens, idx, options, env, self) {
+ // If you are sure other plugins can't add `target` - drop check below
+ const aIndex = tokens[idx].attrIndex('target')
+
+ if (aIndex < 0) {
+ tokens[idx].attrPush(['target', '_blank']) // add new attribute
+ } else {
+ tokens[idx].attrs[aIndex][1] = '_blank' // replace value of existing attr
+ }
+
+ // pass token to default renderer.
+ return defaultRender(tokens, idx, options, env, self)
+ }
+ }
+
+ markdownToHTML (markdown: string) {
+ return this.markdownIt.render(markdown)
+ }
+}