'use strict'

const Promise = require('bluebird')
const dust = require('dustjs-linkedin')

dust.renderPromise = Promise.promisify(dust.render, { context: dust })

module.exports = async function (template, master) {
  const locals = Object.assign({}, this.app.locals, this.locals)
  console.log(locals)

  let html

  if (this.cache) {
    html = this.cache.html
  }

  if (!html && template) {
    html = await dust.renderPromise(template, locals)
  }

  // always render master, since shim mw will add
  // scripts depending on user agent string
  if (typeof master === 'function') {
    html = master(Object.assign({ html }, locals))
  }

  this.send(html)
}