//用于修改webpack默认配置
const { override, addWebpackAlias, fixBabelImports, addLessLoader, addBabelPlugin } = require('customize-cra')
const CompressionWebpackPlugin = require('compression-webpack-plugin')
const BundleAnalyzerPlugin = require('webpack-bundle-analyzer')
  .BundleAnalyzerPlugin
const webpack = require('webpack')
const path = require('path')
const darkThemeVars = require('antd/dist/dark-theme');

// 分析打包大小
const addAnalyze = () => (config) => {
  let plugins = [new BundleAnalyzerPlugin({ analyzerPort: 7777 })]
  config.plugins = [...config.plugins, ...plugins]
  return config
}

// 打包体积优化
const addOptimization = () => (config) => {
  if (process.env.NODE_ENV === 'production') {
    config.optimization = {
      splitChunks: {
        chunks: 'all',
        minSize: 30000,
        maxSize: 0,
        minChunks: 1,
        maxAsyncRequests: 5,
        maxInitialRequests: 3,
        automaticNameDelimiter: '~',
        name: true,
        cacheGroups: {
          vendors: {
            test: /[\\/]node_modules[\\/]/,
            priority: 10
          },
          default: {
            minChunks: 2,
            priority: -10,
            reuseExistingChunk: true
          }
        }
      }
    }

    // 关闭sourceMap
    config.devtool = false
    // 添加js打包gzip配置
    config.plugins.push(
      new CompressionWebpackPlugin({
        test: /\.js$|\.css$/,
        threshold: 1024
      }),
      new webpack.optimize.AggressiveMergingPlugin(), //合并块
      new webpack.optimize.ModuleConcatenationPlugin()
    )
  }
  return config
}

module.exports = override(
  // addAnalyze(),
  // 配置路径别名
  addWebpackAlias({
    '@': path.resolve('src')
  }),
  addOptimization(),
  // 针对antd 实现按需打包：根据import来打包 (使用babel-plugin-import)
  fixBabelImports('import', {
    libraryName: 'antd',
    libraryDirectory: 'es',
    style: true//自动打包相关的样式 默认为 style:'css'
  }),
  // 使用less-loader对源码重的less的变量进行重新制定，设置antd自定义主题
  addLessLoader({
    javascriptEnabled: true,
    modifyVars: {
      'hack': `true;@import "${require.resolve('antd/lib/style/color/colorPalette.less')}";`,
      ...darkThemeVars,
      '@primary-color': '#6e41ff',
    },
    localIdentName: '[local]--[hash:base64:5]' // use less-modules
  })
)