// require() of an ES module (sketches/require-esm.md). The goldens under
// tests/goldens/guests/require-esm are what Node v24.16 printed for the guests in
// tests/fixtures/guests/require-esm; each must match or be a known divergence,
// asserted as what the kernel prints instead.
import { readFileSync } from "node:fs";
import { test, expect, type Page } from "@playwright/test";
import type { Kernel } from "../src/host/index";
import { listGoldens, readGolden } from "../scripts/golden-files.ts";
import { goldenTest, runGoldenGuest } from "./guest";
import { cacheTarballs } from "./tarball-cache";

declare global {
  interface Window { __runtime?: Kernel }
}

const DIVERGES: Record<string, { why: string; stdout: string }> = {
  "require-esm/esm-cycle.cjs": {
    why: "a named import read inside a cycle before its exporter ran is undefined, not a TDZ ReferenceError",
    stdout: '["A","B","A"] undefined:undefined\n',
  },
  "require-esm/live-binding.cjs": {
    why: "a named import is a snapshot taken as the graph evaluates, so its exporter's later reassignment is not seen",
    stdout: '[[0,"f"],[0,"f"]]\n',
  },
  "require-esm/strict-write.cjs": {
    why: "the namespace is a Proxy, so a strict-mode write throws V8's Proxy message",
    stdout: "TypeError 'set' on proxy: trap returned falsish for property 'n'\n",
  },
};

const guests = listGoldens("guests", "require-esm/");
test("every listed guest has a golden", () => {
  expect(Object.keys(DIVERGES).filter((g) => !guests.includes(g))).toEqual([]);
});
for (const guest of guests) {
  const g = readGolden("guests", guest);
  const diverges = DIVERGES[guest];
  if (diverges === undefined) goldenTest(g);
  else {
    test(`golden ${guest} diverges: ${diverges.why}`, async ({ page }) => {
      const out = await runGoldenGuest(page, g);
      expect(out.stdout).not.toBe(g.stdout);
      expect(out).toEqual({ code: g.code, signal: null, stdout: diverges.stdout, stderr: g.stderr });
    });
  }
}

/** `npm ci` from the fixture's lockfile in /app, then `node <entry>` there. */
async function installAndRun(page: Page, dir: string, entry: string): Promise<{ code: number; stdout: string; stderr: string }> {
  await page.goto("/demo/fixture.html");
  await page.waitForFunction(() => window.__runtime !== undefined, undefined, { timeout: 20_000 });
  const files = Object.fromEntries(["package.json", "package-lock.json", entry].map((f) => [`/app/${f}`, readFileSync(`${dir}/${f}`, "utf8")]));
  return page.evaluate(async ({ files, entry }) => {
    const runtime = window.__runtime!;
    runtime.writeTree(files);
    await runtime.install();
    const proc = runtime.exec(`/app/${entry}`, { cwd: "/app" });
    const dec = new TextDecoder();
    let stdout = "";
    let stderr = "";
    await Promise.all([
      proc.stdout.pipeTo(new WritableStream({ write: (c) => { stdout += dec.decode(c); } })),
      proc.stderr.pipeTo(new WritableStream({ write: (c) => { stderr += dec.decode(c); } })),
      proc.exited,
    ]);
    return { code: await proc.exited, stdout, stderr };
  }, { files, entry });
}

test.describe("rolldown's wasm32-wasi binding", () => {
  test.beforeEach(async ({ context }) => cacheTarballs(context));

  // tests/fixtures/require-esm-emnapi pins the graph rolldown's binding loads:
  // @napi-rs/wasm-runtime's runtime.cjs requires @emnapi/core, which is ESM only at
  // 2.0.0-beta.2. node.txt is `npm ci && node main.cjs` there under Node v24.16.
  test("require('@napi-rs/wasm-runtime') loads @emnapi/core v2 as Node does", async ({ page }) => {
    const dir = "tests/fixtures/require-esm-emnapi";
    expect(await installAndRun(page, dir, "main.cjs")).toEqual({ code: 0, stdout: readFileSync(`${dir}/node.txt`, "utf8"), stderr: "" });
  });

  // The installer adds @rolldown/binding-wasm32-wasi, which rolldown's loader falls
  // back to. node.txt is what Node v24.16 printed for main.mjs with only that binding
  // installed and NAPI_RS_FORCE_WASI=1; the lockfile is npm 11.7's.
  test("rolldown parses and bundles through its wasm binding as Node does", async ({ page }) => {
    test.setTimeout(120_000);
    const dir = "tests/fixtures/rolldown-wasi";
    const res = await installAndRun(page, dir, "main.mjs");
    const warning = "(node:PID) ExperimentalWarning: WASI is an experimental feature and might change at any time\n"
      + "(Use `node --trace-warnings ...` to show where the warning was created)\n";
    expect({ ...res, stderr: res.stderr.replace(/\(node:\d+\)/g, "(node:PID)") })
      .toEqual({ code: 0, stdout: readFileSync(`${dir}/node.txt`, "utf8"), stderr: warning + warning });
  });
});