// Event-loop behaviors a guest can observe.
import { test, expect } from "@playwright/test";

test("process.nextTick from an async continuation runs without another event", async ({ page }) => {
  await page.goto("/demo/fixture.html");
  await page.waitForFunction(() => window.__runtime !== undefined, undefined, { timeout: 20_000 });
  const text = await page.evaluate(async () => {
    const runtime = window.__runtime!;
    runtime.writeTree({
      "/app/tick.cjs": [
        'require("node:http").createServer(async (req, res) => {',
        "  await new Promise((resolve) => setTimeout(resolve, 5));",
        '  process.nextTick(() => res.end("ticked"));',
        "}).listen(3100);",
      ].join("\n"),
    });
    runtime.exec("/app/tick.cjs");
    const url = await runtime.waitForPort(3100);
    return await (await fetch(url)).text();
  });
  expect(text).toBe("ticked");
});

test("a fetch started from a callback keeps the process alive until its answer", async ({ page, context }) => {
  // Answered late, so a loop that ignored the fetch would exit first.
  await context.route("**/slow-answer.txt", async (route) => {
    await new Promise((resolve) => setTimeout(resolve, 300));
    await route.fulfill({ status: 200, contentType: "text/plain", body: "late answer" });
  });
  const { runGuest } = await import("./guest");
  const out = await runGuest(page, {
    "/app/main.cjs": 'setTimeout(async () => console.log((await fetch(new URL("/slow-answer.txt", location.origin))).status, "fetched"), 1);',
  }, "/app/main.cjs");
  expect(out).toEqual({ code: 0, signal: null, stdout: "200 fetched\n", stderr: "" });
});