const { readFileSync } = require("fs");
const { resolve } = require("path");

const { BannerPlugin, EnvironmentPlugin } = require("webpack");
const WorkerPlugin = require("worker-plugin");

const { merge } = require("webpack-merge");
const {
	argv: { mode },
} = require("yargs");

const { name: filename, version } = require("./package.json");

const banner = readFileSync(resolve("./_includes/header.txt"), "utf-8");

const ASSET_PATH = "/assets/js/";

const envConfig = (() => {
	switch (mode) {
		case "production":
			return {
				devtool: false,
				plugins: [
					new WorkerPlugin({ globalObject: "self" }),
					new BannerPlugin({ banner, raw: true }),
					new EnvironmentPlugin({
						DEBUG: false,
						ASSET_PATH,
						GET_CLAPS_API: "https://worker.getclaps.app",
					}),
				],
			};

		default:
			return {
				devtool: "source-map",
				plugins: [
					new WorkerPlugin({ globalObject: "self" }),
					new EnvironmentPlugin({
						DEBUG: true,
						ASSET_PATH,
						GET_CLAPS_API: "https://worker.getclaps.dev",
					}),
				],
			};
	}
})();

const sharedPreset = {
	modules: false,
	useBuiltIns: "entry",
	corejs: 2,
};

const babelPresetLegacy = {
	babelrc: false,
	presets: [
		[
			"@babel/preset-env",
			{
				...sharedPreset,
				targets: {
					ie: "11",
				},
			},
		],
	],
};

const babelPresetModern = {
	babelrc: false,
	presets: [
		[
			"@babel/preset-env",
			{
				...sharedPreset,
				targets: {
					esmodules: true,
				},
			},
		],
	],
};

const sharedConfig = {
	entry: resolve("./_js/src/entry.js"),

	output: {
		path: resolve("./assets/js"),
		publicPath: ASSET_PATH,
	},
	resolve: {
		modules: [
			resolve("./_js"),
			resolve("./node_modules"),
			...(process.env.NODE_PATH ? [resolve(process.env.NODE_PATH)] : []),
		],
		extensions: [".json", ".js"],
		symlinks: true,
	},
	optimization: {
		splitChunks: {
			// chunks: 'all',
			// minSize: 30000,
			// maxSize: 0,
			// minChunks: 1,
			// maxAsyncRequests: 5,
			// maxInitialRequests: 3,
			// automaticNameDelimiter: '~',
			// automaticNameMaxLength: 30,
			// name: true,
			// cacheGroups: {
			//   vendors: {
			//     test: /[\\/]node_modules[\\/]/,
			//     priority: -10
			//   },
			//   default: {
			//     minChunks: 2,
			//     priority: -20,
			//     reuseExistingChunk: true
			//   }
			// }
		},
	},
	performance: {
		hints: "warning",
		maxEntrypointSize: 512000,
		maxAssetSize: 512000,
	},
};

module.exports = [
	merge(envConfig, sharedConfig, {
		output: {
			filename: `${filename}-${version}.js`,
			chunkFilename: `[name]-${filename}-${version}.js`,
		},
		module: {
			rules: [
				{
					test: /(\.jsx|\.js)$/,
					loader: "babel-loader",
					options: babelPresetModern,
				},
				{
					test: /modernizr-custom/,
					use: "null-loader",
				},
				{
					test: /@webcomponents\/(template|url|webcomponents-platform)/,
					use: "null-loader",
				},
			],
		},
	}),
	merge(envConfig, sharedConfig, {
		output: {
			filename: `LEGACY-${filename}-${version}.js`,
			chunkFilename: `LEGACY-[name]-${filename}-${version}.js`,
		},
		module: {
			rules: [
				{
					test: /(\.jsx|\.js)$/,
					loader: "babel-loader",
					options: babelPresetLegacy,
				},
			],
		},
	}),
];