// runtime.onProcesses / runtime.kill(pid): an embedder sees the processes a guest spawns
// (npm run dev, then its server) and which of them owns each port.
import { test, expect } from "@playwright/test";
import "./guest";

const PARENT = `
const { spawn } = require("node:child_process");
const child = spawn("node", ["child.cjs", "--flag"], { cwd: "/app/srv", stdio: "inherit" });
child.on("exit", (code, signal) => console.log("child", code, signal));
`;

const CHILD = `
const http = require("node:http");
http.createServer((req, res) => res.end("ok")).listen(4600, () => {
  const extra = http.createServer((req, res) => res.end());
  extra.listen(4601, () => setTimeout(() => extra.close(), 50));
});
`;

test("the table tracks a guest's child, its ports, and its end by kill(pid)", async ({ page }) => {
  await page.goto("/demo/fixture.html");
  await page.waitForFunction(() => window.__runtime !== undefined, undefined, { timeout: 20_000 });
  const result = await page.evaluate(async ({ parent, child }) => {
    const runtime = window.__runtime!;
    runtime.writeTree({ "/app/parent.cjs": parent, "/app/srv/child.cjs": child });
    const tables: unknown[] = [];
    runtime.onProcesses((table) => tables.push(table));
    const proc = runtime.exec("/app/parent.cjs", { argv: ["a"] });
    const pid = await proc.pid;
    const url = await runtime.waitForPort(4600);
    await new Promise<void>((resolve) => {
      const off = runtime.onUnlistening((port) => { if (port === 4601) { off(); resolve(); } });
    });
    runtime.kill(pid + 1);
    const code = await proc.exited;
    const status = (await fetch(url)).status;
    let out = "";
    const reader = proc.stdout.getReader();
    for (let r = await reader.read(); !r.done; r = await reader.read()) out += new TextDecoder().decode(r.value);
    return { pid, tables, code, status, out };
  }, { parent: PARENT, child: CHILD });
  const parentRow = { pid: 1, ppid: null, argv: ["node", "/app/parent.cjs", "a"], cwd: "/app", ports: [] };
  const childRow = (ports: number[]) => ({ pid: 2, ppid: 1, argv: ["node", "/app/srv/child.cjs", "--flag"], cwd: "/app/srv", ports });
  expect(result.pid).toBe(1);
  expect(result.tables).toEqual([
    [],
    [parentRow],
    [parentRow, childRow([])],
    [parentRow, childRow([4600])],
    [parentRow, childRow([4600, 4601])],
    [parentRow, childRow([4600])],
    [parentRow, childRow([])],
    [parentRow],
    [],
  ]);
  expect(result.out).toBe("child null SIGTERM\n");
  expect(result.code).toBe(0);
  expect(result.status).toBe(502);
});

test("a late subscriber gets the current table, and kill(pid) takes a signal", async ({ page }) => {
  await page.goto("/demo/fixture.html");
  await page.waitForFunction(() => window.__runtime !== undefined, undefined, { timeout: 20_000 });
  const result = await page.evaluate(async () => {
    const runtime = window.__runtime!;
    runtime.writeTree({ "/app/srv.cjs": 'require("node:http").createServer((q, s) => s.end()).listen(4602);' });
    const proc = runtime.exec("/app/srv.cjs");
    await runtime.waitForPort(4602);
    const first = await new Promise((resolve) => {
      const off = runtime.onProcesses((table) => { off(); resolve(table); });
    });
    runtime.kill(await proc.pid, "SIGINT");
    runtime.kill(99);
    return { first, code: await proc.exited, signal: await proc.signal };
  });
  expect(result).toEqual({
    first: [{ pid: 1, ppid: null, argv: ["node", "/app/srv.cjs"], cwd: "/app", ports: [4602] }],
    code: 130,
    signal: "SIGINT",
  });
});