'use strict'
const path = require('path')
const utils = require('./utils')
const webpack = require('webpack')
const config = require('../config')
const { merge } = require('webpack-merge')
const baseWebpackConfig = require('./webpack.base.conf')
const CopyWebpackPlugin = require('copy-webpack-plugin')
const HtmlWebpackPlugin = require('html-webpack-plugin')
const ExtractTextPlugin = require('extract-text-webpack-plugin')
const OptimizeCSSPlugin = require('optimize-css-assets-webpack-plugin')
const UglifyJsPlugin = require('uglifyjs-webpack-plugin')

const env = require('../config/prod.env')

const webpackConfig = merge(baseWebpackConfig, {
  mode: 'production',
  module: {
    rules: utils.styleLoaders({
      sourceMap: config.build.productionSourceMap,
      extract: true,
      usePostCSS: true
    })
  },
  devtool: config.build.productionSourceMap ? config.build.devtool : false,
  output: {
    path: config.build.assetsRoot,
    filename: utils.assetsPath('js/[name].[chunkhash].js'),
    chunkFilename: utils.assetsPath('js/[id].[chunkhash].js')
  },
  optimization: {
    splitChunks: {
      chunks: 'all',
      cacheGroups: {
        vendors: {
          name: 'vendor',
          test: /[\\/]node_modules[\\/]/,
          priority: -10,
          chunks: 'initial'
        },
        app: {
          name: 'app',
          test: /[\\/]src[\\/]/,
          priority: -20,
          chunks: 'initial'
        },
        commons: {
          name: 'commons',
          minChunks: 2,
          priority: -30,
          chunks: 'initial',
          reuseExistingChunk: true
        }
      }
    },
    runtimeChunk: {
      name: 'manifest'
    },
    minimizer: [
      new UglifyJsPlugin({
        uglifyOptions: {
          compress: {
            warnings: false,
            drop_console: true,
            drop_debugger: true
          }
        },
        sourceMap: config.build.productionSourceMap,
        parallel: true
      })
    ]
  },
  performance: {
    hints: 'warning',
    maxAssetSize: 1024000,
    maxEntrypointSize: 2048000,
    assetFilter: function (assetFilename) {
      return assetFilename.endsWith('.js') || assetFilename.endsWith('.css')
    }
  },
  plugins: [
    new webpack.DefinePlugin({
      'process.env': env
    }),
    new ExtractTextPlugin({
      filename: utils.assetsPath('css/[name].[hash].css'),
      allChunks: true,
    }),
    new OptimizeCSSPlugin({
      cssProcessorOptions: config.build.productionSourceMap
        ? { safe: true, map: { inline: false } }
        : { safe: true }
    }),
    new HtmlWebpackPlugin({
      filename: config.build.index,
      template: 'index.html',
      inject: true,
      minify: {
        removeComments: true,
        collapseWhitespace: true,
        removeAttributeQuotes: true,
        minifyCSS: true,
        minifyJS: true
      },
      chunksSortMode: 'auto'
    }),
    new webpack.HashedModuleIdsPlugin(),
    new CopyWebpackPlugin([
      {
        from: path.resolve(__dirname, '../static'),
        to: config.build.assetsSubDirectory,
        ignore: ['.*']
      }
    ])
  ]
})

if (config.build.productionGzip) {
  const CompressionWebpackPlugin = require('compression-webpack-plugin')

  webpackConfig.plugins.push(
    new CompressionWebpackPlugin({
      asset: '[path].gz[query]',
      algorithm: 'gzip',
      test: new RegExp(
        '\\.(' +
        config.build.productionGzipExtensions.join('|') +
        ')$'
      ),
      threshold: 10240,
      minRatio: 0.8
    })
  )
}

if (config.build.bundleAnalyzerReport) {
  const BundleAnalyzerPlugin = require('webpack-bundle-analyzer').BundleAnalyzerPlugin
  webpackConfig.plugins.push(new BundleAnalyzerPlugin())
}

module.exports = webpackConfig