markdown-it/lib/rules_inline/autolink.js

// Process autolinks '<protocol:...>'

'use strict';

var url_schemas   = require('../common/url_schemas');
var normalizeLink = require('../helpers/normalize_link');


/*eslint max-len:0*/
var EMAIL_RE    = /^<([a-zA-Z0-9.!#$%&'*+\/=?^_`{|}~-]+@[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?(?:\.[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?)*)>/;
var AUTOLINK_RE = /^<([a-zA-Z.\-]{1,25}):([^<>\x00-\x20]*)>/;


module.exports = function autolink(state, silent) {
  var tail, linkMatch, emailMatch, url, fullUrl, pos = state.pos;

  if (state.src.charCodeAt(pos) !== 0x3C/* < */) { return false; }

  tail = state.src.slice(pos);

  if (tail.indexOf('>') < 0) { return false; }

  linkMatch = tail.match(AUTOLINK_RE);

  if (linkMatch) {
    if (url_schemas.indexOf(linkMatch[1].toLowerCase()) < 0) { return false; }

    url = linkMatch[0].slice(1, -1);
    fullUrl = normalizeLink(url);
    if (!state.parser.validateLink(url)) { return false; }

    if (!silent) {
      state.push({
        type: 'link_open',
        href: fullUrl,
        level: state.level
      });
      state.push({
        type: 'text',
        content: url,
        level: state.level + 1
      });
      state.push({ type: 'link_close', level: state.level });
    }

    state.pos += linkMatch[0].length;
    return true;
  }

  emailMatch = tail.match(EMAIL_RE);

  if (emailMatch) {

    url = emailMatch[0].slice(1, -1);

    fullUrl = normalizeLink('mailto:' + url);
    if (!state.parser.validateLink(fullUrl)) { return false; }

    if (!silent) {
      state.push({
        type: 'link_open',
        href: fullUrl,
        level: state.level
      });
      state.push({
        type: 'text',
        content: url,
        level: state.level + 1
      });
      state.push({ type: 'link_close', level: state.level });
    }

    state.pos += emailMatch[0].length;
    return true;
  }

  return false;
};