const path = require('path')
const CompressionPlugin = require('compression-webpack-plugin');

const resolve = dir => {
    return path.join(__dirname, dir)
}

module.exports = {
    css: {
        loaderOptions: { // 向 CSS 相关的 loader 传递选项
          less: {
            lessOptions: {
              javascriptEnabled: true
            }
          }
        }
      },
    devServer: {
        port: 9998,
    },

    chainWebpack: config => {
      //  @ 对应 src目录
        config.resolve.alias.set('@', resolve('src'))
    },

    // 打包时不生成.map文件 避免看到源码
    productionSourceMap: false,

    // 部署优化
    configureWebpack: {
        // 使用CDN
        externals: {
            vue: 'Vue',
            'vue-i18n': 'VueI18n',
            axios: 'axios',
            'vue-router': 'VueRouter',
            vuex: 'Vuex',
            'view-design': 'iview',
            'vue-apexcharts': 'VueApexCharts',
            xlsx: 'XLSX',
            dplayer: 'DPlayer',
            'print-js': 'printJS',
            html2canvas: 'html2canvas',
            'vue-json-pretty': 'VueJsonPretty',
            'vue-lazyload': 'VueLazyload',
            gitalk: 'Gitalk',
            'js-cookie': 'Cookies',
            wangEditor: 'wangEditor',
            quill: 'Quill',
            stompjs: 'Stomp',
            'sockjs-client': 'SockJS',
            vuedraggable: 'vuedraggable'
        },
        // GZIP压缩
        plugins: [
            new CompressionPlugin({
                test: /\.js$|\.html$|\.css/, // 匹配文件
                threshold: 10240 // 对超过10k文件压缩
            })
        ],
        optimization: {
          runtimeChunk: "single",
          splitChunks: {
            chunks: "all",
            maxInitialRequests: Infinity,
            minSize: 20000,
            cacheGroups: {
              vendor: {
                test: /[\\/]node_modules[\\/]/,
                name(module) {
                  const packageName = module.context.match(
                    /[\\/]node_modules[\\/](.*?)([\\/]|$)/
                  )[1];
                  return `npm.${packageName.replace("@", "")}`;
                }
              }
            }
          }
        }
    },
    pluginOptions: {
      'style-resources-loader': {
        preProcessor: 'scss',
        patterns: [path.resolve(__dirname, './src/styles/common.scss')]
      }
    }
}