text: 'use strict'
  
  const fs = require('fs')
  const path = require('path')
  const swBuild = require('workbox-build')
  const config = require('./workbox.config.json')
  
  const buildPrefix = '_gh_pages/'
  
  const workboxSWSrcPath = require.resolve('workbox-sw')
  const wbFileName = path.basename(workboxSWSrcPath)
  const workboxSWDestPath = `${buildPrefix}assets/js/vendor/${wbFileName}`
  const workboxSWSrcMapPath = `${workboxSWSrcPath}.map`
  const workboxSWDestMapPath = `${workboxSWDestPath}.map`
  
  fs.createReadStream(workboxSWSrcPath).pipe(fs.createWriteStream(workboxSWDestPath))
  fs.createReadStream(workboxSWSrcMapPath).pipe(fs.createWriteStream(workboxSWDestMapPath))
  
  const updateUrl = (manifestEntries) => {
    const manifest = manifestEntries.map((entry) => {
      if (entry.url.startsWith(buildPrefix)) {
        const regex = new RegExp(buildPrefix, 'g')
        entry.url = entry.url.replace(regex, '')
      }
      return entry
    })
    return {
      manifest,
      warnings: []
    }
  }
  
  config.manifestTransforms = [updateUrl]
  
  swBuild.injectManifest(config).then(({
    count,
    size
  }) => {
    const wbSwRegex = /{fileName}/g
    fs.readFile(config.swDest, 'utf8', (err, data) => {
      if (err) {
        throw err
      }
      const swFileContents = data.replace(wbSwRegex, wbFileName)
      fs.writeFile(config.swDest, swFileContents, () => {
        console.log(`Pre-cache Manifest generated. Pre-cached ${count} files, totalling ${size} bytes.`)
      })
    })
  }).catch((error) => {
    console.error(`Something went wrong: ${error}`)
  })
  