'use strict'
const path = require('path')
const defaultSettings = require('./src/settings.js')

const webpack = require('webpack')
const CompressionWebpackPlugin = require('compression-webpack-plugin')//这个插件可以看官网还是很好用的
const productionGzipExtensions = ['js', 'css']//对什么文件进行压缩
const Timestamp = new Date().getTime();//防止http的缓存每次打包用时间戳进行区分
const {BASE_URL }= require('./src/utils/config.js');

function resolve(dir) {
  return path.join(__dirname, dir)
}


const name = defaultSettings.title || '后台' // page title

// If your port is set to 80,
// use administrator privileges to execute the command line.
// For example, Mac: sudo npm run
// You can change the port by the following methods:
// port = 9528 npm run dev OR npm run dev --port = 9528
const port = process.env.port || process.env.npm_config_port || 9528 // dev port

// All configuration item explanations can be find in https://cli.vuejs.org/config/
module.exports = {
  /**
   * You will need to set publicPath if you plan to deploy your site under a sub path,
   * for example GitHub Pages. If you plan to deploy your site to https://foo.github.io/bar/,
   * then publicPath should be set to "/bar/".
   * In most cases please use '/' !!!
   * Detail: https://cli.vuejs.org/config/#publicpath
   */
  publicPath: '/',
  outputDir: 'dist',
  assetsDir: 'static',
  lintOnSave: false,
  productionSourceMap: false,
  devServer: {
    port: port,
    open: true,
    overlay: {
      warnings: false,
      errors: true
    },
    //	反向代理
    proxy: {
      '^/api/baidu': {
        target: 'https://api.map.baidu.com/',//代理
        changeOrigin: true,//是否跨域
        pathRewrite: {
          '^/api/baidu': ''
        }
      },
      '^/api': {
        // target: 'http://192.168.110.153:9002/',//代理
        target: BASE_URL,//代理
        changeOrigin: true,//是否跨域
        pathRewrite: {
          '^/api': ''
        }
      },
    }
    // before: require('./mock/mock-server.js')
  },
  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,
    output: { // 输出重构  打包编译后的 文件名称 
      filename: `js/[name]${Timestamp}.js`,
      chunkFilename: `js/[name]${Timestamp}.js`
    },
    plugins: [
      new webpack.IgnorePlugin(/^\.\/locale$/, /moment$/),//该插件能够使得指定目录被忽略，从而使得打包变快，文件变小
      // 下面是下载的插件的配置
      new CompressionWebpackPlugin({
        cache:false,
        algorithm: 'gzip',//压缩算法
        test: new RegExp('\\.(' + productionGzipExtensions.join('|') + ')$'),//处理所有匹配此 {RegExp} 的资源
        threshold: 512,//只处理比这个值大的资源。按字节计算
        minRatio: 0.8//只有压缩率比这个值小的资源才会被处理
      }),
      new webpack.optimize.LimitChunkCountPlugin({
        maxChunks: 15, //控制打包生成js的个数
        minChunkSize: 100
      })
    ],
    resolve: {
      alias: {
        '@': resolve('src')
      }
    }
  },
  chainWebpack(config) {
    // it can improve the speed of the first screen, it is recommended to turn on preload
    config.plugin('preload').tap(() => [
      {
        rel: 'preload',
        // to ignore runtime.js
        // https://github.com/vuejs/vue-cli/blob/dev/packages/@vue/cli-service/lib/config/app.js#L171
        fileBlacklist: [/\.map$/, /hot-update\.js$/, /runtime\..*\.js$/],
        include: 'initial'
      }
    ])

    // 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')
        }
      )
  }
}