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 { terser } from "rollup-plugin-terser";
import config from "sapper/config/rollup.js";
import sveltePreprocess from "svelte-preprocess";

import pkg from "./package.json";

const mode = process.env.NODE_ENV;
const dev = mode === "development";
const legacy = !!process.env.SAPPER_LEGACY_BUILD;

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

const preprocess = sveltePreprocess({ postcss: true });

export default {
  client: {
    input: config.client.input(),
    output: config.client.output(),
    plugins: [
      replace({
        "process.browser": true,
        "process.env.NODE_ENV": JSON.stringify(mode),
        preventAssignment: true
      }),
      svelte({
        preprocess,
        dev,
        hydratable: true,
        emitCss: true
      }),
      resolve({
        browser: true,
        dedupe: ["svelte"]
      }),
      commonjs(),

      legacy &&
        babel({
          extensions: [".js", ".mjs", ".html", ".svelte"],
          babelHelpers: "runtime",
          exclude: ["node_modules/@babel/**"],
          presets: [
            [
              "@babel/preset-env",
              {
                targets: "> 0.25%, not dead"
              }
            ]
          ],
          plugins: [
            "@babel/plugin-syntax-dynamic-import",
            [
              "@babel/plugin-transform-runtime",
              {
                useESModules: true
              }
            ]
          ]
        }),

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

    preserveEntrySignatures: false,
    onwarn
  },

  server: {
    input: config.server.input(),
    output: config.server.output(),
    plugins: [
      replace({
        "process.browser": false,
        "process.env.NODE_ENV": JSON.stringify(mode),
        preventAssignment: true
      }),
      svelte({
        preprocess,
        generate: "ssr",
        hydratable: true,
        dev
      }),
      resolve({
        dedupe: ["svelte"]
      }),
      commonjs()
    ],
    external: Object.keys(pkg.dependencies).concat(
      require("module").builtinModules
    ),

    preserveEntrySignatures: "strict",
    onwarn
  },

  // 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()
  //   ],

  //   preserveEntrySignatures: false,
  //   onwarn
  // }
};