test.js

var mdIt = require('markdown-it'),
    MarkdownItVideo =require('markdown-it-video')
    md = new mdIt();
md.use(MarkdownItVideo);
md.use(videoPlugin);

console.log(md.render('$[video](https://videos.contentful.com/9sf2shpojqu3/4lW8CjEX2UsYuMeKY2eo4k/8445be5ffdc2eb10650bdd9560a24215/675_DieterBlum_Trailer_en.mp4 https://images.contentful.com/9sf2shpojqu3/1lmIs3xvpKYikwAOAe0kiK/3ebec843171ad8f4c1735526c2bb7816/677-337224-12__2_.jpg)'))



//The implementation is taken from
//https://github.com/brianjgeiger/markdown-it-video/blob/master/index.js
// Process $[video](contentful-video-url)
/*
  API:
  $[video](https://videos.contentful.com/vpx322qexe3h/1kvcghNoxauKoYSk6gWIAI/16868f3923186fa49325a2343e498240/431_435_Supersale_final.mp4)
  $[video](https://videos.contentful.com/ loop autoplay)
  $[video](https://videos.contentful.com/ loop)
*/
'use strict';

const videoTypes = {
  'mp4': 'video/mp4',
  'webm': 'video/webm',
  'ogv': 'video/ogg'
};
var players = {};
var videoRegex = /^https:\/\/videos.contentful.com\/(.+)$/;
var imageRegex = /^(https:\/\/[^\s]*\.jpe?g|png|gif|bmp)$/i;

var EMBED_REGEX = /\$\[([a-zA-Z].+)\]\([\s]*([^)]*?)[\s]*[\)]/im;
var defaults = {
  url: videoUrl,
  video: {},
};

function videoPlugin(md, options = {}) {
var _extends = Object.assign || function (target) { for (var i = 1; i < arguments.length; i++) { var source = arguments[i]; for (var key in source) { if (Object.prototype.hasOwnProperty.call(source, key)) { target[key] = source[key]; } } } return target; };

var opts = _extends({}, options, defaults);
  md.renderer.rules.video = tokenizeVideo(md, opts);
  console.log('i1', md.renderer.rules.video);
  md.inline.ruler.before('emphasis', 'video', videoEmbed(md, opts));
  console.log('i2');
};

function init(el) {
  const videPlaceholder = el.querySelector('[data-video-src]');
  const src = videPlaceholder && videPlaceholder.getAttribute('data-video-src');
  const id = videPlaceholder && videPlaceholder.getAttribute('id');
  const options = videPlaceholder && videPlaceholder.getAttribute('options');
  if (!videPlaceholder || !src) return;

  if (!window.flowplayer) {
    const script = document.createElement('script');
    script.setAttribute('async', true);
    script.onload = playVideo.bind(this, videPlaceholder, src, id, options);
    script.src = '/_assets/flow-player/flowplayer.min.js';
    document.body.appendChild(script);
    const style = document.createElement('link');
    style.setAttribute('async', true);
    style.rel = 'stylesheet';
    style.href = '/_assets/flow-player/skin/minimalist.css';

    document.querySelector('head').appendChild(style);
  }
  else {
    playVideo(videPlaceholder, src, id, options);
  }
};

function destroy(el) {
  const videPlaceholder = el.querySelector('[data-video-src]');
  const id = videPlaceholder && videPlaceholder.getAttribute('id');
  if (players[id]) {
    players[id].unload();
    delete players[id];
  }
};

function playVideo(videPlaceholder, src, id, options) {
  const videoExtension = src.split('.').pop().toLowerCase();

  var config = {
      embed: false,
      swf: '/_assets/flow-player/flowplayer.swf',
      muted: true,
      ratio: 9 / 16,
      key: window.conf.flowPlayerLicense || '$127465123735801',
      onBeforeUnload: ()=>true,
      clip:  {
        sources: [{
          type: videoTypes[videoExtension],
          src: src
        }]
      }
    },
    listOfOptionsToApply = options.split(','),
    videoPreviewNode = document.getElementById(`${id}-preview`);
  if (videoPreviewNode) {
    videoPreviewNode.onclick = function() {
      players[id].play();
      videoPreviewNode.className += ' playing';
    };
  }
  config = listOfOptionsToApply.reduce((conf, option) => {
    conf[option] = true;
    return conf;
  }, config);

  players[id] = window.flowplayer(videPlaceholder,  config);
  players[id].one('ready', () => {
    if (config.autoplay) players[id].play();
  });

}

function videoParser(url) {
  var match = url.match(videoRegex);
  return match ? match[1] : url;
}
function videoEmbed(md, options) {
  function videoReturn(state, silent) {
    var serviceEnd,
      serviceStart,
      token,
      oldPos = state.pos,
      match,
      service,
      videoID,
      optsID,
      firstImage,
      serviceLower,
      newState;

    if (state.src.charAt(oldPos) !== '$'/* @ */ ||
        state.src.charCodeAt(oldPos + 1) !== 0x5B/* [ */) {
      return false;
    }

    match = /\$\[([a-zA-Z].+)\]\([\s]*([^)]*?)[\s]*[\)]/im.exec(state.src);
console.log(match)
    if (!match || match.length < 3) {
      return false;
    }

    service = match[1];
    videoID = match[2];
    optsID = videoID.split(' ');
    if (Array.isArray(optsID)) {
      videoID = optsID.shift();
      firstImage = optsID.reduce((result, opt) => {
        if (result) return result;
        if (imageRegex.test(opt)) return opt;
        return null;
      }, null);
    }
    else {
      optsID = null;
    }
    console.log(1)
    serviceLower = service.toLowerCase();

    if (serviceLower === 'video') {
      videoID = videoParser(videoID);
    }
    else if (!options[serviceLower]) {
      return false;
    }
console.log(2)
    // If the videoID field is empty, regex currently make it the close parenthesis.
    if (videoID === ')') {
      videoID = '';
    }
console.log(3)
    serviceStart = oldPos + 2;
    serviceEnd = md.helpers.parseLinkLabel(state, oldPos + 1, false);

    //
    // We found the end of the link, and know for a fact it's a valid link;
    // so all that's left to do is to call tokenizer.
    //
    console.log(4)
    if (!silent) {
      state.pos = serviceStart;
      state.posMax = serviceEnd;
      state.service = state.src.slice(serviceStart, serviceEnd);
      newState = new state.md.inline.State(service, state.md, state.env, []);
      newState.md.inline.tokenize(newState);

      token = state.push('video', '');
      token.videoID = videoID;
      token.optsID = optsID;
      token.firstImage = firstImage;
      token.service = service;
      token.level = state.level;
    }
console.log(5)
    state.pos = state.pos + state.src.indexOf(')', state.pos);
    state.posMax = state.tokens.length;
    return true;
  }

  return videoReturn;
}

function videoUrl(service, videoID) {
  switch (service) {
  case 'video':
    return '//videos.contentful.com/' + videoID;
  }
}

function tokenizeVideo(md, options) {
  function tokenizeReturn(tokens, idx) {
    console.log('i6');
    const videoID = md.utils.escapeHtml(tokens[idx].videoID);
    const service = md.utils.escapeHtml(tokens[idx].service).toLowerCase();
    const videoOpts = tokens[idx].optsID && tokens[idx].optsID.join(',');
    const uniqueId = Math.floor(Math.random()*999999);
    console.log('i5');
    const firstImageBlock = tokens[idx].firstImage ? `<div class="md-video__preview" id="${uniqueId}-preview"><img src="${tokens[idx].firstImage}" class="md-video__preview-image"/>
      <div class="md-video__preview-play-button">
        <div class="md-video__preview-circle">
        </div>
        <div class="md-video__preview-inner-circle">
        </div>
      </div>
    </div>` : '';
    return videoID === '' ? '' :
      `<div class="flow-player-wrapper">
        <div id="${uniqueId}" data-video-src="${videoUrl(service, videoID, options)}" options="${videoOpts || ''}"></div>
        ${firstImageBlock}
      </div>`;
  }
  return tokenizeReturn;
}