'use strict'
const path = require('path')
require("babel-polyfill");
const productionGzipExtensions = ['js', 'css'];
const UglifyJsPlugin = require("uglifyjs-webpack-plugin");
const CompressionWebpackPlugin = require('compression-webpack-plugin');
const isProduction = process.env.NODE_ENV === 'production';
function resolve(dir) {
  return path.join(__dirname, dir)
}


const port = process.env.port || process.env.npm_config_port || 8080 

module.exports = {
  publicPath: '/',
  outputDir: 'dist',
  assetsDir: 'static',
  lintOnSave: false,
  productionSourceMap: false,
  devServer: {
    port: port,
    open: true,
    overlay: {
      warnings: false,
      errors: true
    },
  },
  configureWebpack: config => {
    // 入口文件
    config.entry.app = ["babel-polyfill", "./src/main.js"];
    config.externals = {
      'vue': 'Vue',
      axios: "axios",
      'vue-router': 'VueRouter'
    };
    // if (isProduction) {
    config.plugins.push(new CompressionWebpackPlugin({
      algorithm: 'gzip',
      test: new RegExp('\\.(' + productionGzipExtensions.join('|') + ')$'),
      threshold: 10240,
      minRatio: 0.7
    }))
    // }
    let plugins = [
      new UglifyJsPlugin({
        uglifyOptions: {
          compress: {
            drop_console: true,
            drop_debugger: true
          },
          output: {
            comments: true
          }
        },
        cache: true,
        sourceMap: false,
        parallel: true
      })
    ];

    // if (isProduction) {
    config.plugins = [...config.plugins, ...plugins];
    // }
  },

  chainWebpack(config) {
    config.plugin('preload').tap(() => [
      {
        rel: 'preload',
        fileBlacklist: [/\.map$/, /hot-update\.js$/, /runtime\..*\.js$/],
        include: 'initial'
      }
    ])
    config.plugins.delete('prefetch')
    config.module
      .rule('svg')
      .exclude.add(resolve('src/icons'))
      .end()
    config.module
      .rule('icons')
      .test(/\.svg$/)
      .include.add(resolve('src/icons'))
      .end()
      .use('svg-sprite-loader')
      .loader('svg-sprite-loader')
      .options({
        symbolId: 'icon-[name]'
      })
      .end()
    config
      .when(true,
        config => {
          config
            .plugin('ScriptExtHtmlWebpackPlugin')
            .after('html')
            .use('script-ext-html-webpack-plugin', [{
              inline: /runtime\..*\.js$/
            }])
            .end()
          config
            .optimization.splitChunks({
              chunks: 'all',
              cacheGroups: {
                libs: {
                  name: 'chunk-libs',
                  test: /[\\/]node_modules[\\/]/,
                  priority: 10,
                  chunks: 'initial'
                },
                elementUI: {
                  name: 'chunk-elementUI',
                  priority: 20,
                  test: /[\\/]node_modules[\\/]_?element-ui(.*)/
                },
                commons: {
                  name: 'chunk-commons',
                  test: resolve('src/components'),
                  minChunks: 3,
                  priority: 5,
                  reuseExistingChunk: true
                }
              }
            })
          config.optimization.runtimeChunk('single')
        }
      )
  }
}