index.js

'use strict';

const {join} = require('path');
const {readFileSync} = require('fs');

const docinfoFunctions = require('./src/docinfo.js');
const css = readFileSync(join(__dirname, 'src', 'style.css')).toString();

// The default version of the runner is based on the version of Node running this code
const DEFAULT_NODE_VERSION = process.version.split('.').shift();

const isInteractive = (type) => {
  return (block) => block.isAttribute('language', type) && block.isOption('interactive');
};

const interactiveRunnerTreeProcessor = function(){
  const self = this;
  self.process(function(doc){
    doc.findBy({ context: 'listing' }, isInteractive('javascript'))
      .forEach(block => {
        const nodeVersion = doc.getAttribute('runner-node') || DEFAULT_NODE_VERSION;

        block.addRole('interactive');
        block.addRole('interactive--javascript');
        block.addRole(`interactive--runtime--node-${nodeVersion}`);
        block.setAttribute('runtime', 'runkit');

        if (block.isOption('endpoint')) {
          block.addRole('interactive--endpoint');
        }
      });
  });
};

const interactiveRunnerDocinfoProcessor = function(){
  const self = this;
  self.process(function(doc){
    const blocks = doc.findBy({ context: 'listing' }, b => b.isAttribute('runtime', 'runkit'));

    if (blocks.length === 0 || doc.backend !== 'html5') {
      return '';
    }

    return `<style type="text/css" class="extension-interactive-runner">${css}</style>
<script class="extension-interactive-runner">
(function(d){
  document.addEventListener('DOMContentLoaded', function(){
    const script = d.createElement('script');
    script.src = 'https://embed.runkit.com/';
    script.async = true;
    script.onload = function(){
      ${docinfoFunctions.map(f => f.toString()).join('\n')}
      installEvents();
      document.body.dataset.interactiveRuntime = 'loaded';
    };
    document.body.appendChild(script);
  });
})(document);</script>`;
  });
};

module.exports = function (registry) {
  registry.treeProcessor(interactiveRunnerTreeProcessor)
  registry.docinfoProcessor(interactiveRunnerDocinfoProcessor)
}

module.exports.register = function register (registry) {
  if (typeof registry.register === 'function') {
    registry.register(function () {
      this.treeProcessor(interactiveRunnerTreeProcessor)
      this.docinfoProcessor(interactiveRunnerDocinfoProcessor)
    })
  }

  return registry
};