const isProduction = process.env.NODE_ENV === 'production'
const proCDN = {
  css: [
    'https://cdn.bootcss.com/element-ui/2.13.0/theme-chalk/index.css'
  ],
  js: [
    'https://cdn.bootcss.com/babel-polyfill/6.23.0/polyfill.min.js',
    'https://cdn.bootcss.com/vue/2.6.11/vue.min.js',
    'https://cdn.jsdelivr.net/npm/vue-router@3.1.6/dist/vue-router.min.js',
    'https://cdn.bootcss.com/vuex/3.1.3/vuex.min.js'
  ]
}
const devCDN = {
  css: [
  ],
  js: [
    'https://cdn.bootcss.com/babel-polyfill/6.23.0/polyfill.min.js'
  ]
}
const path = require('path')
function resolve(dir) {
    return path.join(__dirname, dir)
}
module.exports = {
  publicPath: './',
  productionSourceMap: !isProduction,
  chainWebpack: config => {
    config.plugin('html')
          .tap(args => {
              args[0].cdn = isProduction ? proCDN : devCDN;
              return args;
          });
    // set svg-sprite-loader
    config.module
      .rule('svg')
      .exclude.add(resolve('src/icons'))
      .end()
    config.module
      .rule('icons')
      .test(/\.svg$/)
      .include.add(resolve('src/icons'))
      .end()
      .use('svg-sprite-loader')
      .loader('svg-sprite-loader')
      .options({
        symbolId: 'icon-[name]'
      })
      .end()
  },
  configureWebpack: config => {
    if (isProduction) {
        // 用cdn方式引入
        config.externals = {
          'vue': 'Vue',
          'vuex': 'Vuex',
          'element-ui': 'ELEMENT',
          'vue-router': 'VueRouter'
        }
    }
  },
  css: {
      // 向预处理器 Loader 传递选项
      loaderOptions: {
          scss: {
            // 全局变量
            prependData: `
              @import "~@/assets/css/index.scss";
            `
          }
      },
      // css 生成名称默认配置
      /* extract: {
        filename: `css/[name].[contenthash:8].css`,
        chunkFilename: `css/[name].[contenthash:8].css`
      } */
  },
  // 文件名称不需要hash
  // filenameHashing: false,
  "transpileDependencies": [
    "element-ui",
    "vuetify"
  ]
}