/**
 * Running a command and waiting for a condition — the two things every step below needs.
 *
 * The waiting matters more than it looks. Every readiness check here polls for an OBSERVABLE FACT rather
 * than trusting a live pid, because each of these processes can be alive and not yet usable: Xvfb forks
 * before its socket answers, wine returns while the window is still being created, and x11vnc exits after
 * printing an error if the display went away. A pid check passes for all three and the next step then fails
 * in a way that reads as the game being broken.
 */

export type RunResult = { ok: boolean; stdout: string; stderr: string; code: number };

export async function run(cmd: string[], env: Record<string, string> = {}, timeoutMs = 30_000): Promise<RunResult> {
  const proc = Bun.spawn(cmd, {
    env: { ...process.env, ...env },
    stdout: 'pipe',
    stderr: 'pipe',
    stdin: 'ignore',
  });

  const killer = setTimeout(() => proc.kill('SIGKILL'), timeoutMs);
  try {
    const [stdout, stderr] = await Promise.all([new Response(proc.stdout).text(), new Response(proc.stderr).text()]);
    const code = await proc.exited;
    return { ok: code === 0, stdout, stderr, code };
  } finally {
    clearTimeout(killer);
  }
}

/** Poll `check` until it is true. Resolves false on timeout rather than throwing — every caller reports. */
export async function waitFor(check: () => boolean | Promise<boolean>, timeoutMs: number, everyMs = 250) {
  const deadline = Date.now() + timeoutMs;
  for (;;) {
    if (await check()) return true;
    if (Date.now() >= deadline) return false;
    await Bun.sleep(everyMs);
  }
}