/** 这是用于开发环境的webpack配置文件 **/

const path = require("path"); // 获取绝对路径用
const webpack = require("webpack"); // webpack核心
const { CleanWebpackPlugin } = require("clean-webpack-plugin"); // 每次打包前清除旧的build文件夹
const VueLoaderPlugin = require("vue-loader/lib/plugin");
const TerserPlugin = require("terser-webpack-plugin"); // 优化js
const OptimizeCSSAssetsPlugin = require("optimize-css-assets-webpack-plugin"); // 压缩CSS
module.exports = {
  mode: "production",
  entry: [
    "./src/index.js", // 项目入口
  ],
  output: {
    path: path.resolve(__dirname, "dist"), // 将打包好的文件放在此路径下，dev模式中，只会在内存中存在，不会真正的打包到此路径
    filename: "[name].js", //编译后的文件名字
    library: ["vue-flip-down"],
    libraryTarget: "umd",
  },
  externals: {
    vue: "vue",
  },
  optimization: {
    minimizer: [
      new TerserPlugin({
        parallel: true, // 多线程并行构建
        terserOptions: {
          // https://github.com/terser/terser#minify-options
          compress: {
            warnings: false, // 删除无用代码时是否给出警告
            drop_console: true, // 删除所有的console.*
            drop_debugger: true, // 删除所有的debugger
          },
        },
      }),
      new OptimizeCSSAssetsPlugin({}),
    ],
    splitChunks: {
      chunks: "all",
    },
  },
  module: {
    rules: [
      {
        test: /\.vue$/,
        use: ["vue-loader"],
        include: path.resolve(__dirname, "src"),
      },
      {
        // .js .jsx用babel解析
        test: /\.js?$/,
        use: ["babel-loader"],
        include: path.resolve(__dirname, "src"),
      },
      {
        // .css 解析
        test: /\.css$/,
        use: ["style-loader", "css-loader", "postcss-loader"],
        include: path.resolve(__dirname, "src"),
      },
      {
        // .less 解析
        test: /\.less$/,
        use: ["style-loader", "css-loader", "postcss-loader", "less-loader"],
        include: path.resolve(__dirname, "src"),
      },
      {
        // 文件解析
        test: /\.(eot|woff|otf|svg|ttf|woff2|appcache|mp3|mp4|pdf)(\?|$)/,
        include: path.resolve(__dirname, "src"),
        use: ["file-loader?name=assets/[name].[ext]"],
      },
      {
        // 图片解析
        test: /\.(png|jpg|gif)(\?|$)/,
        include: path.resolve(__dirname, "src"),
        use: ["url-loader?limit=8192&name=assets/[name].[ext]"],
      },
    ],
  },
  plugins: [new VueLoaderPlugin(), new CleanWebpackPlugin()],
  resolve: {
    extensions: [".js", ".vue", ".less", ".css"], //后缀名自动补全
    alias: {
      "@": path.resolve(__dirname, "src"),
    },
  },
};