// webapck打包的配置文件
'use strict' // 开启严格模式
const path = require('path') // nodejs遵循 CommonJS规范  导入和导出
const defaultSettings = require('./src/settings.js')

// 将传入的相对路径变成绝对路径
function resolve(dir) {
  // 获取当前文件所在的绝对路径
  return path.join(__dirname, dir)
}

// 设置网页的标题
const name = defaultSettings.title || 'vue Admin Template' // page title

// 设置项目的端口号
const port = process.env.port || process.env.npm_config_port || 9528 // dev port
let externals = {}
let cdn = { css: [], js: [] }
const isProduction = process.env.NODE_ENV === 'production' // 判断是否是生产环境
if (isProduction) {
  externals = {
    /**
      * externals 对象属性解析：
      * '包名' : '在项目中引入的名字'
    */
    'vue': 'Vue',
    'element-ui': 'ELEMENT',
    'xlsx': 'XLSX'
  }
  cdn = {
    css: [
      'https://lib.baomitu.com/element-ui/2.13.2/theme-chalk/index.css' // element-ui css 样式表
    ],
    js: [
      // vue must at first!
      'https://lib.baomitu.com/vue/2.6.10/vue.min.js', // vuejs
      'https://lib.baomitu.com/element-ui/2.13.2/index.js', // element-ui js
      'https://lib.baomitu.com/xlsx/0.16.0/xlsx.min.js' // xlsx
    ]
  }
}
// vue-cli 进行配置 https://cli.vuejs.org/config/
module.exports = {
  // 设置打包输出的静态资源在任何环境下打开 '' 获取 './'  默认是'/'只能在服务器的环境运行
  publicPath: './',
  // 设置打包输出目录的名称
  outputDir: 'dist',
  // 设置打包输出目录里静态资源的目录名称
  assetsDir: 'static',
  // 是否打开eslint检查
  lintOnSave: process.env.NODE_ENV === 'development',
  // 是否开启映射
  productionSourceMap: false,
  // 设置脚手架提供的devServer
  devServer: {
    port: port, // 设置端口号
    open: true, // 浏览器是否自动打开
    // 设置在浏览器显示的错误等级
    overlay: {
      warnings: false,
      errors: true
    },
    proxy: {
      '/api': {
        target: 'http://192.168.74.59:3000'
      }
    }
    // before: require('./mock/mock-server.js')
  },
  // webpack配置【对象配置】
  configureWebpack: {
    // provide the app's title in webpack's name field, so that
    // it can be accessed in index.html to inject the correct title.
    name: name,
    externals: externals,
    resolve: {
      alias: {
        '@': resolve('src')
      }
    }
  },
  // webpack配置【函数配置】
  chainWebpack(config) {
    // it can improve the speed of the first screen, it is recommended to turn on preload
    // 去除log
    config.optimization.minimizer('terser').tap((args) => {
      args[0].terserOptions.compress.drop_console = true
      return args
    })

    config.plugin('preload').tap(() => [
      {
        rel: 'preload',
        // to ignore runtime.js
        // https://github.com/vuejs/vue-cli/blob/dev/packages/@vue/cli-service/lib/config/app.js#L171
        fileBlacklist: [/\.map$/, /hot-update\.js$/, /runtime\..*\.js$/],
        include: 'initial'
      }
    ])

    // 注入cdn变量 (打包时会执行)
    config.plugin('html').tap(args => {
      args[0].cdn = cdn // 配置cdn给插件
      return args
    })
    // 省略其他...

    // when there are many pages, it will cause too many meaningless requests
    config.plugins.delete('prefetch')

    // 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()

    config
      .when(process.env.NODE_ENV !== 'development',
        config => {
          config
            .plugin('ScriptExtHtmlWebpackPlugin')
            .after('html')
            .use('script-ext-html-webpack-plugin', [{
            // `runtime` must same as runtimeChunk name. default is `runtime`
              inline: /runtime\..*\.js$/
            }])
            .end()
          config
            .optimization.splitChunks({
              chunks: 'all',
              cacheGroups: {
                libs: {
                  name: 'chunk-libs',
                  test: /[\\/]node_modules[\\/]/,
                  priority: 10,
                  chunks: 'initial' // only package third parties that are initially dependent
                },
                elementUI: {
                  name: 'chunk-elementUI', // split elementUI into a single package
                  priority: 20, // the weight needs to be larger than libs and app or it will be packaged into libs or app
                  test: /[\\/]node_modules[\\/]_?element-ui(.*)/ // in order to adapt to cnpm
                },
                commons: {
                  name: 'chunk-commons',
                  test: resolve('src/components'), // can customize your rules
                  minChunks: 3, //  minimum common number
                  priority: 5,
                  reuseExistingChunk: true
                }
              }
            })
          // https:// webpack.js.org/configuration/optimization/#optimizationruntimechunk
          config.optimization.runtimeChunk('single')
        }
      )
  }
}