'use strict';

const path = require('path');
const webpack = require('webpack');
const PnpWebpackPlugin = require('pnp-webpack-plugin');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const InlineChunkHtmlPlugin = require('react-dev-utils/InlineChunkHtmlPlugin');
const TerserPlugin = require('terser-webpack-plugin');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const OptimizeCSSAssetsPlugin = require('optimize-css-assets-webpack-plugin');
const safePostCssParser = require('postcss-safe-parser');
const ManifestPlugin = require('webpack-manifest-plugin');
const InterpolateHtmlPlugin = require('react-dev-utils/InterpolateHtmlPlugin');
const WorkboxWebpackPlugin = require('workbox-webpack-plugin');
const ModuleScopePlugin = require('react-dev-utils/ModuleScopePlugin');
const getCSSModuleLocalIdent = require('react-dev-utils/getCSSModuleLocalIdent');
const paths = require('./paths');
const getClientEnvironment = require('./env');
const getCacheIdentifier = require('react-dev-utils/getCacheIdentifier');
const ModuleNotFoundPlugin = require('react-dev-utils/ModuleNotFoundPlugin');

// Webpack uses `publicPath` to determine where the app is being served from.
// It requires a trailing slash, or the file assets will get an incorrect path.
const publicPath = paths.servedPath;
// Some apps do not use client-side routing with pushState.
// For these, "homepage" can be set to "." to enable relative asset paths.
const shouldUseRelativeAssetPaths = publicPath === './';
// Source maps are resource heavy and can cause out of memory issue for large source files.
const shouldUseSourceMap = process.env.GENERATE_SOURCEMAP !== 'false';
// `publicUrl` is just like `publicPath`, but we will provide it to our app
// as %PUBLIC_URL% in `index.html` and `process.env.PUBLIC_URL` in JavaScript.
// Omit trailing slash as %PUBLIC_URL%/xyz looks better than %PUBLIC_URL%xyz.
const publicUrl = publicPath.slice(0, -1);
// Get environment variables to inject into our app.
const env = getClientEnvironment(publicUrl);

// Assert this just to be safe.
// Development builds of React are slow and not intended for production.
if (env.stringified['process.env'].NODE_ENV !== '"production"') {
	throw new Error('Production builds must have NODE_ENV=production.');
}

// style files regexes
const cssRegex = /\.css$/;
const cssModuleRegex = /\.module\.css$/;
const sassRegex = /\.(scss|sass)$/;
const sassModuleRegex = /\.module\.(scss|sass)$/;
const lessRegex = /\.less$/;
const lessModuleRegex = /\.module\.less/;

// common function to get style loaders
const getStyleLoaders = (cssOptions, preProcessor) => {
	const loaders = [
		{
			loader: MiniCssExtractPlugin.loader,
			options: Object.assign(
				{},
				shouldUseRelativeAssetPaths ? { publicPath: '../../' } : undefined
			),
		},
		{
			loader: require.resolve('css-loader'),
			options: cssOptions,
		},
		{
			// Options for PostCSS as we reference these options twice
			// Adds vendor prefixing based on your specified browser support in
			// package.json
			loader: require.resolve('postcss-loader'),
			options: {
				// Necessary for external CSS imports to work
				// https://github.com/facebook/create-react-app/issues/2677
				ident: 'postcss',
				plugins: () => [
					require('postcss-flexbugs-fixes'),
					require('postcss-preset-env')({
						autoprefixer: {
							flexbox: 'no-2009',
						},
						stage: 3,
					}),
				],
				sourceMap: shouldUseSourceMap,
			},
		},
	];
	if (preProcessor) {
		loaders.push({
			loader: require.resolve(preProcessor),
			options: {
				sourceMap: shouldUseSourceMap,
			},
		});
	}
	return loaders;
};

// This is the production configuration.
// It compiles slowly and is focused on producing a fast and minimal bundle.
// The development configuration is different and lives in a separate file.
module.exports = {
	mode: 'production',
	// Don't attempt to continue if there are any errors.
	bail: true,
	// We generate sourcemaps in production. This is slow but gives good results.
	// You can exclude the *.map files from the build during deployment.
	devtool: shouldUseSourceMap ? 'source-map' : false,
	// In production, we only want to load the app code.
	entry: [paths.appIndexJs],
	output: {
		// The build folder.
		path: paths.appBuild,
		// Generated JS file names (with nested folders).
		// There will be one main bundle, and one file per asynchronous chunk.
		// We don't currently advertise code splitting but Webpack supports it.
		filename: 'static/js/[name].[chunkhash:8].js',
		chunkFilename: 'static/js/[name].[chunkhash:8].chunk.js',
		// We inferred the "public path" (such as / or /my-project) from homepage.
		publicPath: publicPath,
		// Point sourcemap entries to original disk location (format as URL on Windows)
		devtoolModuleFilenameTemplate: info =>
			path
				.relative(paths.appSrc, info.absoluteResourcePath)
				.replace(/\\/g, '/'),
	},
	optimization: {
		minimizer: [
			new TerserPlugin({
				terserOptions: {
					parse: {
						// we want terser to parse ecma 8 code. However, we don't want it
						// to apply any minfication steps that turns valid ecma 5 code
						// into invalid ecma 5 code. This is why the 'compress' and 'output'
						// sections only apply transformations that are ecma 5 safe
						// https://github.com/facebook/create-react-app/pull/4234
						ecma: 8,
					},
					compress: {
						ecma: 5,
						warnings: false,
						// Disabled because of an issue with Uglify breaking seemingly valid code:
						// https://github.com/facebook/create-react-app/issues/2376
						// Pending further investigation:
						// https://github.com/mishoo/UglifyJS2/issues/2011
						comparisons: false,
						// Disabled because of an issue with Terser breaking valid code:
						// https://github.com/facebook/create-react-app/issues/5250
						// Pending futher investigation:
						// https://github.com/terser-js/terser/issues/120
						inline: 2,
					},
					mangle: {
						safari10: true,
					},
					output: {
						ecma: 5,
						comments: false,
						// Turned on because emoji and regex is not minified properly using default
						// https://github.com/facebook/create-react-app/issues/2488
						ascii_only: true,
					},
				},
				// Use multi-process parallel running to improve the build speed
				// Default number of concurrent runs: os.cpus().length - 1
				parallel: true,
				// Enable file caching
				cache: true,
				sourceMap: shouldUseSourceMap,
			}),
			new OptimizeCSSAssetsPlugin({
				cssProcessorOptions: {
					parser: safePostCssParser,
					map: shouldUseSourceMap
						? {
							// `inline: false` forces the sourcemap to be output into a
							// separate file
							inline: false,
							// `annotation: true` appends the sourceMappingURL to the end of
							// the css file, helping the browser find the sourcemap
							annotation: true,
						}
						: false,
				},
			}),
		],
		// Automatically split vendor and commons
		// https://twitter.com/wSokra/status/969633336732905474
		// https://medium.com/webpack/webpack-4-code-splitting-chunk-graph-and-the-splitchunks-optimization-be739a861366
		splitChunks: {
			chunks: 'all',
			name: false,
		},
		// Keep the runtime chunk seperated to enable long term caching
		// https://twitter.com/wSokra/status/969679223278505985
		runtimeChunk: true,
	},
	resolve: {
		// This allows you to set a fallback for where Webpack should look for modules.
		// We placed these paths second because we want `node_modules` to "win"
		// if there are any conflicts. This matches Node resolution mechanism.
		// https://github.com/facebook/create-react-app/issues/253
		modules: ['node_modules'].concat(
			// It is guaranteed to exist because we tweak it in `env.js`
			process.env.NODE_PATH.split(path.delimiter).filter(Boolean)
		),
		// These are the reasonable defaults supported by the Node ecosystem.
		// We also include JSX as a common component filename extension to support
		// some tools, although we do not recommend using it, see:
		// https://github.com/facebook/create-react-app/issues/290
		// `web` extension prefixes have been added for better support
		// for React Native Web.
		extensions: ['.mjs', '.web.js', '.js', '.json', '.web.jsx', '.jsx'],
		alias: {
			// Support React Native Web
			// https://www.smashingmagazine.com/2016/08/a-glimpse-into-the-future-with-react-native-for-web/
			'react-native': 'react-native-web',
			// 全局相对路径别名，处理相对路径过长和繁琐问题
			'@': paths.appSrc
		},
		plugins: [
			// Adds support for installing with Plug'n'Play, leading to faster installs and adding
			// guards against forgotten dependencies and such.
			PnpWebpackPlugin,
			// Prevents users from importing files from outside of src/ (or node_modules/).
			// This often causes confusion because we only process files within src/ with babel.
			// To fix this, we prevent you from importing files out of src/ -- if you'd like to,
			// please link the files into your node_modules/ and let module-resolution kick in.
			// Make sure your source files are compiled, as they will not be processed in any way.
			new ModuleScopePlugin(paths.appSrc, [paths.appPackageJson]),
		],
	},
	resolveLoader: {
		plugins: [
			// Also related to Plug'n'Play, but this time it tells Webpack to load its loaders
			// from the current package.
			PnpWebpackPlugin.moduleLoader(module),
		],
	},
	module: {
		strictExportPresence: true,
		rules: [
			// Disable require.ensure as it's not a standard language feature.
			{ parser: { requireEnsure: false } },

			// First, run the linter.
			// It's important to do this before Babel processes the JS.
			{
				test: /\.(js|mjs|jsx)$/,
				enforce: 'pre',
				use: [
					{
						options: {
							formatter: require.resolve('react-dev-utils/eslintFormatter'),
							eslintPath: require.resolve('eslint'),

						},
						loader: require.resolve('eslint-loader'),
					},
				],
				include: paths.appSrc,
			},
			{
				// "oneOf" will traverse all following loaders until one will
				// match the requirements. When no loader matches it will fall
				// back to the "file" loader at the end of the loader list.
				oneOf: [
					// "url" loader works just like "file" loader but it also embeds
					// assets smaller than specified size as data URLs to avoid requests.
					{
						test: [/\.bmp$/, /\.gif$/, /\.jpe?g$/, /\.png$/],
						loader: require.resolve('url-loader'),
						options: {
							limit: 10000,
							name: 'static/media/[name].[hash:8].[ext]',
						},
					},
					// Process application JS with Babel.
					// The preset includes JSX, Flow, and some ESnext features.
					{
						test: /\.(js|mjs|jsx)$/,
						include: paths.appSrc,

						loader: require.resolve('babel-loader'),
						options: {
							customize: require.resolve(
								'babel-preset-react-app/webpack-overrides'
							),

							plugins: [
								[
									require.resolve('babel-plugin-named-asset-import'),
									{
										loaderMap: {
											svg: {
												ReactComponent: '@svgr/webpack?-prettier,-svgo![path]',
											},
										},
									},
								],
								['import', { libraryName: 'antd', libraryDirectory: 'es', style: true }],
							],
							cacheDirectory: true,
							// Save disk space when time isn't as important
							cacheCompression: true,
							compact: true,
						},
					},
					// Process any JS outside of the app with Babel.
					// Unlike the application JS, we only compile the standard ES features.
					{
						test: /\.(js|mjs)$/,
						exclude: /@babel(?:\/|\\{1,2})runtime/,
						loader: require.resolve('babel-loader'),
						options: {
							babelrc: false,
							configFile: false,
							compact: false,
							presets: [
								[
									require.resolve('babel-preset-react-app/dependencies'),
									{ helpers: true },
								],
							],
							cacheDirectory: true,
							// Save disk space when time isn't as important
							cacheCompression: true,

							// If an error happens in a package, it's possible to be
							// because it was compiled. Thus, we don't want the browser
							// debugger to show the original code. Instead, the code
							// being evaluated would be much more helpful.
							sourceMaps: false,
						},
					},
					// "postcss" loader applies autoprefixer to our CSS.
					// "css" loader resolves paths in CSS and adds assets as dependencies.
					// `MiniCSSExtractPlugin` extracts styles into CSS
					// files. If you use code splitting, async bundles will have their own separate CSS chunk file.
					// By default we support CSS Modules with the extension .module.css
					{
						test: cssRegex,
						exclude: cssModuleRegex,
						loader: getStyleLoaders({
							importLoaders: 1,
							sourceMap: shouldUseSourceMap,
						}),
						// Don't consider CSS imports dead code even if the
						// containing package claims to have no side effects.
						// Remove this when webpack adds a warning or an error for this.
						// See https://github.com/webpack/webpack/issues/6571
						sideEffects: true,
					},
					// Adds support for CSS Modules (https://github.com/css-modules/css-modules)
					// using the extension .module.css
					{
						test: cssModuleRegex,
						loader: getStyleLoaders({
							importLoaders: 1,
							sourceMap: shouldUseSourceMap,
							modules: true,
							getLocalIdent: getCSSModuleLocalIdent,
						}),
					},
					// Opt-in support for SASS. The logic here is somewhat similar
					// as in the CSS routine, except that "sass-loader" runs first
					// to compile SASS files into CSS.
					// By default we support SASS Modules with the
					// extensions .module.scss or .module.sass
					{
						test: sassRegex,
						exclude: sassModuleRegex,
						loader: getStyleLoaders(
							{
								importLoaders: 2,
								sourceMap: shouldUseSourceMap,
							},
							'sass-loader'
						),
						// Don't consider CSS imports dead code even if the
						// containing package claims to have no side effects.
						// Remove this when webpack adds a warning or an error for this.
						// See https://github.com/webpack/webpack/issues/6571
						sideEffects: true,
					},
					// Adds support for CSS Modules, but using SASS
					// using the extension .module.scss or .module.sass
					{
						test: sassModuleRegex,
						loader: getStyleLoaders(
							{
								importLoaders: 2,
								sourceMap: shouldUseSourceMap,
								modules: true,
								getLocalIdent: getCSSModuleLocalIdent,
							},
							'sass-loader'
						),
					},
					// Opt-in support for LESS (using .less extensions).
					{
						test: lessRegex,
						exclude: lessModuleRegex,
						loader: getStyleLoaders({ 
							importLoaders: 2,
							sourceMap: shouldUseSourceMap,
						}, 'less-loader'),
					},
					// Adds support for CSS Modules, but using LESS
					// using the extension .module.scss or .module.sass
					{
						test: lessModuleRegex,
						loader: getStyleLoaders(
							{
								importLoaders: 2,
								sourceMap: shouldUseSourceMap,
								modules: true,
								getLocalIdent: getCSSModuleLocalIdent,
							},
							'less-loader'
						),
					},
					// "file" loader makes sure assets end up in the `build` folder.
					// When you `import` an asset, you get its filename.
					// This loader doesn't use a "test" so it will catch all modules
					// that fall through the other loaders.
					{
						loader: require.resolve('file-loader'),
						// Exclude `js` files to keep "css" loader working as it injects
						// it's runtime that would otherwise be processed through "file" loader.
						// Also exclude `html` and `json` extensions so they get processed
						// by webpacks internal loaders.
						exclude: [/\.(js|mjs|jsx)$/, /\.html$/, /\.json$/],
						options: {
							name: 'static/media/[name].[hash:8].[ext]',
						},
					},
					// ** STOP ** Are you adding a new loader?
					// Make sure to add the new loader(s) before the "file" loader.
				],
			},
		],
	},
	plugins: [
		// Generates an `index.html` file with the <script> injected.
		new HtmlWebpackPlugin({
			inject: true,
			template: paths.appHtml,
			minify: {
				removeComments: true,
				collapseWhitespace: true,
				removeRedundantAttributes: true,
				useShortDoctype: true,
				removeEmptyAttributes: true,
				removeStyleLinkTypeAttributes: true,
				keepClosingSlash: true,
				minifyJS: true,
				minifyCSS: true,
				minifyURLs: true,
			},
		}),
		// Inlines the webpack runtime script. This script is too small to warrant
		// a network request.
		new InlineChunkHtmlPlugin(HtmlWebpackPlugin, [/runtime~.+[.]js/]),
		// Makes some environment variables available in index.html.
		// The public URL is available as %PUBLIC_URL% in index.html, e.g.:
		// <link rel="shortcut icon" href="%PUBLIC_URL%/favicon.ico">
		// In production, it will be an empty string unless you specify "homepage"
		// in `package.json`, in which case it will be the pathname of that URL.
		new InterpolateHtmlPlugin(HtmlWebpackPlugin, env.raw),
		// This gives some necessary context to module not found errors, such as
		// the requesting resource.
		new ModuleNotFoundPlugin(paths.appPath),
		// Makes some environment variables available to the JS code, for example:
		// if (process.env.NODE_ENV === 'production') { ... }. See `./env.js`.
		// It is absolutely essential that NODE_ENV was set to production here.
		// Otherwise React will be compiled in the very slow development mode.
		new webpack.DefinePlugin(env.stringified),
		new MiniCssExtractPlugin({
			// Options similar to the same options in webpackOptions.output
			// both options are optional
			filename: 'static/css/[name].[contenthash:8].css',
			chunkFilename: 'static/css/[name].[contenthash:8].chunk.css',
		}),
		// Generate a manifest file which contains a mapping of all asset filenames
		// to their corresponding output file so that tools can pick it up without
		// having to parse `index.html`.
		new ManifestPlugin({
			fileName: 'asset-manifest.json',
			publicPath: publicPath,
		}),
		// Moment.js is an extremely popular library that bundles large locale files
		// by default due to how Webpack interprets its code. This is a practical
		// solution that requires the user to opt into importing specific locales.
		// https://github.com/jmblog/how-to-optimize-momentjs-with-webpack
		// You can remove this if you don't use Moment.js:
		new webpack.IgnorePlugin(/^\.\/locale$/, /moment$/),
		// Generate a service worker script that will precache, and keep up to date,
		// the HTML & assets that are part of the Webpack build.
		new WorkboxWebpackPlugin.GenerateSW({
			clientsClaim: true,
			exclude: [/\.map$/, /asset-manifest\.json$/],
			importWorkboxFrom: 'cdn',
			navigateFallback: publicUrl + '/index.html',
			navigateFallbackBlacklist: [
				// Exclude URLs starting with /_, as they're likely an API call
				new RegExp('^/_'),
				// Exclude URLs containing a dot, as they're likely a resource in
				// public/ and not a SPA route
				new RegExp('/[^/]+\\.[^/]+$'),
			],
		}),
	],
	// Some libraries import Node modules but don't use them in the browser.
	// Tell Webpack to provide empty mocks for them so importing them works.
	node: {
		dgram: 'empty',
		fs: 'empty',
		net: 'empty',
		tls: 'empty',
		child_process: 'empty',
	},
	// Turn off performance processing because we utilize
	// our own hints via the FileSizeReporter
	performance: false,
};