const path = require('path')

module.exports = async (env) => {
	if (!env.ROOT) throw new Error(`Missing ROOT`)
	if (!env.MODULETYPE) throw new Error(`Missing MODULETYPE`)

	const pkgJson = require(path.join(env.ROOT, 'package.json'))

	if (!pkgJson.main) throw new Error(`Missing main in package.json`)

	let webpackExt = {}
	try {
		webpackExt = require(path.join(env.ROOT, 'build-config.cjs'))

		console.log('Found additional webpack configuration')
	} catch (e) {
		// Ignore
	}

	let externalsExt = []
	if (Array.isArray(webpackExt.externals)) externalsExt = webpackExt.externals
	else if (webpackExt.externals) externalsExt = [webpackExt.externals]

	return {
		entry: {
			main: './' + pkgJson.main, // path.join(frameworkDir, 'dist/entrypoint.js'),
			// Allow for custom entrypoints
			...webpackExt.entry,
		},
		mode: env.dev ? 'development' : 'production',
		output:
			env.MODULETYPE === 'connection'
				? {
						path: path.resolve(env.ROOT, 'pkg'),
					}
				: {
						path: path.resolve(env.ROOT, 'pkg'),
						filename: 'main.js',
						library: {
							type: 'commonjs2',
							// Avoid producing a double default in the bundle
							export: 'default',
						},
					},
		context: path.resolve(env.ROOT, '.'),
		target: 'node',
		externals: [
			// Allow for custom externals
			...externalsExt,
		],
		experiments: {
			topLevelAwait: true,
		},
		optimization: {
			minimize: !webpackExt.disableMinifier,
		},
		module: {
			rules: [
				// {
				// 	test: /\.json$/,
				// 	type: 'asset/source',
				// },
				// {
				// 	test: /BUILD$/,
				// 	type: 'asset/resource',
				// 	generator: {
				// 		filename: 'BUILD',
				// 	},
				// },
			],
		},
		plugins: [
			// Let modules define additional plugins. Hopefully this won't conflict with anything we add
			...(webpackExt.plugins || []),
		],
		node: webpackExt.useOriginalStructureDirname
			? {
					__dirname: true,
				}
			: undefined,
	}
}