import resolve from '@rollup/plugin-node-resolve'
import replace from '@rollup/plugin-replace'
import commonjs from '@rollup/plugin-commonjs'
import svelte from 'rollup-plugin-svelte'
import babel from 'rollup-plugin-babel'
// import { eslint } from 'rollup-plugin-eslint'
// import browsersync from 'rollup-plugin-browsersync'
import autoPreprocess from 'svelte-preprocess'
import { terser } from 'rollup-plugin-terser'
import config from 'sapper/config/rollup'
import pkg from './package.json'

// Define environment and things
const mode = process.env.NODE_ENV
const dev = mode === 'development'
const legacy = !!process.env.SAPPER_LEGACY_BUILD

// Svelte
const onwarn = (warning, onwarn) => (warning.code === 'CIRCULAR_DEPENDENCY' && /[/\\]@sapper[/\\]/.test(warning.message)) || onwarn(warning)

// Preprocessors
const preprocess = autoPreprocess({
	scss: {
		includePaths: ['src', 'node_modules'],
	},
	postcss: true
})


export default {
	/*
	** Client
	*/
	client: {
		input: config.client.input(),
		output: {
			...config.client.output(),
			// ...dev && { exports: 'named' }
		},
		// experimentalCodeSplitting: true,
		plugins: [
			// Javascript
			replace({
				'process.browser': true,
				'process.env.NODE_ENV': JSON.stringify(mode)
			}),
			svelte({
				dev,
				hydratable: true,
				emitCss: true,
				// css: css => css.write('static/bundle.css'),
				preprocess
			}),
			resolve({
				browser: true,
				extensions: ['.mjs', '.js', '.svelte', '.scss', '.json', '.html'],
				dedupe: ['svelte']
			}),
			commonjs(),
			// dev && eslint(),
			legacy && babel({
				extensions: ['.js', '.mjs', '.html', '.svelte'],
				exclude: ['*.scss', '*.css', 'node_modules/@babel/**'],
				runtimeHelpers: true
			}),

			// Compress Javascript
			!dev && terser({
				module: true
			}),
		],

		onwarn,
	},


	/*
	** Server
	*/
	server: {
		input: config.server.input(),
		output: config.server.output(),
		plugins: [
			replace({
				'process.browser': false,
				'process.env.NODE_ENV': JSON.stringify(mode)
			}),
			svelte({
				dev,
				generate: 'ssr',
				preprocess
			}),
			resolve({
				browser: true,
				extensions: ['.mjs', '.js', '.json', '.html', '.svelte', '.scss'],
				dedupe: ['svelte']
			}),
			commonjs(),
		],
		external: Object.keys(pkg.dependencies).concat(
			require('module').builtinModules || Object.keys(process.binding('natives'))
		),

		onwarn,
	},


	/*
	** Service worker
	*/
	// serviceworker: {
	// 	input: config.serviceworker.input(),
	// 	output: config.serviceworker.output(),
	// 	plugins: [
	// 		resolve(),
	// 		replace({
	// 			'process.browser': true,
	// 			'process.env.NODE_ENV': JSON.stringify(mode)
	// 		}),
	// 		commonjs(),
	// 		!dev && terser()
	// 	],

	// 	onwarn,
	// }
}