const path = require("path");
// const BundleAnalyzerPlugin = require("webpack-bundle-analyzer").BundleAnalyzerPlugin;

module.exports = {
  publicPath: "/admin/",
  lintOnSave: process.env.NODE_ENV === "development",
  productionSourceMap: false,
  devServer: {
    open: false,
    // proxy: {
    //   [process.env.VUE_APP_BASE_API]: {
    //     target: process.env.VUE_APP_REMOTE_URL,
    //     changeOrigin: true,
    //     pathRewrite: {
    //       ["^" + process.env.VUE_APP_BASE_API]: ""
    //     }
    //   }
    // },
    // overlay: {
    //   errors: true,
    //   warnings: false
    // }
  },
  configureWebpack: {
    // plugins: [new BundleAnalyzerPlugin()],
  },
  chainWebpack(config) {
    // it can improve the speed of the first screen, it is recommended to turn on preload
    // 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");

    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: path.join(__dirname, "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");
    });
  },
};