const path = require("path");
const webpack = require("webpack");
const userscriptMeta = require("./Extensions/UserScript/userscript.meta");
const {
  USERSCRIPT_ARTIFACT_RELATIVE_PATH,
  USERSCRIPT_BUILD_RECEIPT_RELATIVE_PATH,
  USERSCRIPT_LIVE_ARTIFACT_RELATIVE_PATH,
  USERSCRIPT_LIVE_BUILD_RECEIPT_RELATIVE_PATH,
  UserscriptBuildReceiptPlugin,
} = require("./userscript-build-receipt");
const { LiveBuildMarkerPlugin, createLiveBuildId } = require("./webpack.live-build-marker");

const USERSCRIPT_ASSET_NAME = "Return Youtube Dislike.user.js";

class StripWebpackBootstrapWhitespacePlugin {
  apply(compiler) {
    compiler.hooks.thisCompilation.tap("StripWebpackBootstrapWhitespacePlugin", (compilation) => {
      compilation.hooks.processAssets.tap(
        {
          name: "StripWebpackBootstrapWhitespacePlugin",
          stage: webpack.Compilation.PROCESS_ASSETS_STAGE_OPTIMIZE,
        },
        () => {
          const asset = compilation.getAsset(USERSCRIPT_ASSET_NAME);
          if (!asset) return;

          const source = asset.source.source().toString();
          const normalized = source.replace(/^(\/\*{6}\/)[ \t]+(?=\r?$)/gm, "$1");
          if (normalized === source) return;

          compilation.updateAsset(USERSCRIPT_ASSET_NAME, new webpack.sources.RawSource(normalized));
        },
      );
    });
  }
}

function buildUserscriptBanner(liveTestBuild) {
  const metadata = [
    "// ==UserScript==",
    `// @name         ${userscriptMeta.name}${liveTestBuild ? " [Live Test]" : ""}`,
    `// @namespace    ${userscriptMeta.namespace}`,
    `// @homepage     ${userscriptMeta.homepage}`,
    `// @version      ${userscriptMeta.version}`,
    `// @encoding     ${userscriptMeta.encoding}`,
    `// @description  ${userscriptMeta.description}`,
    `// @icon         ${userscriptMeta.icon}`,
    `// @author       ${userscriptMeta.author}`,
    ...userscriptMeta.match.map((value) => `// @match        ${value}`),
    ...userscriptMeta.exclude.map((value) => `// @exclude      ${value}`),
    ...userscriptMeta.compatible.map((value) => `// @compatible   ${value}`),
    ...(liveTestBuild
      ? []
      : [`// @downloadURL  ${userscriptMeta.downloadURL}`, `// @updateURL    ${userscriptMeta.updateURL}`]),
    ...userscriptMeta.grants.map((value) => `// @grant        ${value}`),
    `// @run-at       ${userscriptMeta.runAt}`,
    "// ==/UserScript==",
    "",
    "// This file is generated by `npm run build:userscript`.",
    "// Edit Extensions/UserScript/src instead of the generated file.",
  ];

  return metadata.join("\n");
}

module.exports = (env = {}, argv = {}) => {
  const liveTestBuild = env.liveTest === true || env.liveTest === "true";
  const liveBuildId = createLiveBuildId(liveTestBuild);
  const mode = argv.mode ?? "production";
  const artifactRelativePath = liveTestBuild
    ? USERSCRIPT_LIVE_ARTIFACT_RELATIVE_PATH
    : USERSCRIPT_ARTIFACT_RELATIVE_PATH;
  const receiptRelativePath = liveTestBuild
    ? USERSCRIPT_LIVE_BUILD_RECEIPT_RELATIVE_PATH
    : USERSCRIPT_BUILD_RECEIPT_RELATIVE_PATH;

  return {
    name: "userscript",
    mode,
    entry: path.resolve(__dirname, "Extensions/UserScript/src/userscript-entry.js"),
    output: {
      path: liveTestBuild
        ? path.resolve(__dirname, "test-results/live-build/userscript")
        : path.resolve(__dirname, "Extensions/UserScript"),
      filename: USERSCRIPT_ASSET_NAME,
      clean: false,
      iife: true,
    },
    cache: false,
    optimization: {
      minimize: false,
    },
    plugins: [
      new webpack.DefinePlugin({
        __RYD_LIVE_BUILD_ID__: JSON.stringify(liveBuildId),
        __RYD_LIVE_TEST_BUILD__: JSON.stringify(liveTestBuild),
      }),
      ...(liveTestBuild ? [new LiveBuildMarkerPlugin(liveBuildId, ["live-build.json"])] : []),
      new StripWebpackBootstrapWhitespacePlugin(),
      new UserscriptBuildReceiptPlugin({
        artifactPath: path.resolve(__dirname, artifactRelativePath),
        buildId: liveBuildId,
        liveTestBuild,
        mode,
        receiptPath: path.resolve(__dirname, receiptRelativePath),
        repositoryRoot: __dirname,
      }),
      new webpack.BannerPlugin({
        banner: buildUserscriptBanner(liveTestBuild),
        raw: true,
        entryOnly: true,
      }),
    ],
    devtool: false,
    performance: {
      hints: false,
    },
  };
};