import MarkdownIt from "markdown-it";
import type { MarkdownIt as MarkdownRenderer, StateCore } from "markdown-it";
import { highlight } from "sugar-high";
import { FilterXSS, safeAttrValue } from "xss";
import { linkTextReferences } from "./references";
export type MarkdownContext = {
owner: string;
repo: string;
ref: string;
/** Directory of the document inside the repo, used to resolve relative links. */
basePath: string;
};
const ATTACHMENT_PREFIX = "/attachments/";
const ABSOLUTE_URL = /^(?:[a-z][a-z0-9+.-]*:|\/\/|#)/i;
function createRenderer(): MarkdownRenderer {
const md = new MarkdownIt({
html: true,
linkify: true,
typographer: false,
highlight: (code) => `<pre class="sh-code"><code>${highlight(code)}</code></pre>`,
});
md.validateLink = (url) =>
!/^(javascript|vbscript|data):/i.test(url.trim()) || /^data:image\/(png|gif|jpe?g|webp);/i.test(url.trim());
return md;
}
const renderer = createRenderer();
const ALIGNED = ["align"];
const CELL = ["align", "colspan", "rowspan"];
const HEADING = ["align", "id"];
/** The raw HTML subset GitHub permits in markdown; everything else (scripts, styles, handlers) is stripped. */
const ALLOWED_HTML: Record<string, string[]> = {
a: ["href", "title", "name", "id"],
img: ["src", "alt", "title", "width", "height", "align"],
picture: [],