const TerserPlugin = require('terser-webpack-plugin');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const CssMinimizerPlugin = require('css-minimizer-webpack-plugin');
const BundleAnalyzerPlugin = require('webpack-bundle-analyzer').BundleAnalyzerPlugin;

const webpackBaseConfig = require('./webpack.base.config');
const { toProjectRoot, isAnalyze } = require('./utils');

webpackBaseConfig.mode = 'production';
webpackBaseConfig.optimization = {
    runtimeChunk: {
        name: 'runtime',
    },
    moduleIds: 'deterministic',
    minimize: true,
    minimizer: [
        // For webpack@5 you can use the `...` syntax to extend existing minimizers (i.e. `terser-webpack-plugin`), uncomment the next line
        `...`,
        new CssMinimizerPlugin({
            parallel: true,
        }),
        new TerserPlugin({
            include: [toProjectRoot('/src')],
            exclude: [/\/node_modules/],
            // default parallel nums：os.cpus().length - 1
            parallel: true,
            terserOptions: {
                ecma: 5,
                sourceMap: false,
            },
        }),
    ],
    splitChunks: {
        chunks: 'async',
        minSize: 20000,
        minRemainingSize: 0,
        minChunks: 1,
        maxAsyncRequests: 30,
        maxInitialRequests: 30,
        enforceSizeThreshold: 50000,
        cacheGroups: {
            defaultVendors: {
                test: /[\\/]node_modules[\\/]/,
                priority: -10,
                reuseExistingChunk: true,
            },
            default: {
                minChunks: 2,
                priority: -20,
                reuseExistingChunk: true,
            },
        },
    },
};
webpackBaseConfig.module.rules = webpackBaseConfig.module.rules.concat([
    {
        test: /\.css$/,
        use: [
            MiniCssExtractPlugin.loader,
            {
                loader: 'css-loader',
                options: {
                    sourceMap: false,
                },
            },
            'postcss-loader',
        ],
        include: [/node_modules[\\/]element-ui/, toProjectRoot('/src')],
    },
    {
        test: /\.scss$/,
        use: [
            MiniCssExtractPlugin.loader,
            {
                loader: 'css-loader',
                options: {
                    sourceMap: false,
                },
            },
            'postcss-loader',
            {
                loader: 'sass-loader',
                options: {
                    sourceMap: false,
                },
            },
        ],
        include: [/node_modules[\\/]element-ui/, toProjectRoot('/src')],
    },
]);
webpackBaseConfig.plugins = webpackBaseConfig.plugins.concat(
    [
        new MiniCssExtractPlugin({
            filename: 'css/[name].[contenthash:8].css',
        }),
        isAnalyze && new BundleAnalyzerPlugin(),
    ].filter(Boolean)
);

module.exports = webpackBaseConfig;