import { ChildProcess } from "node:child_process";

/**
 * Tiered exit strategy for child processes:
 * 1. Send SIGTERM and wait for a grace period
 * 2. Send SIGKILL if still running after the grace period
 *
 * NOTE: This is forward-looking scaffolding for when the codebase
 * manages async child processes directly. Currently process lifecycle
 * is managed through pi-coding-agent internals.
 */
export async function terminateWithGrace(
  child: ChildProcess,
  graceMs: number = 1000
): Promise<void> {
  if (child.killed || child.exitCode !== null) return;

  // 1. Send SIGTERM
  child.kill("SIGTERM");

  // 2. Wait for grace period
  const exitPromise = new Promise<void>((resolve) => {
    child.on("exit", () => resolve());
  });

  const timeoutPromise = new Promise<void>((resolve) => {
    setTimeout(resolve, graceMs);
  });

  await Promise.race([exitPromise, timeoutPromise]);

  // 3. If timeout won, send SIGKILL
  if (child.exitCode === null && !child.killed) {
    child.kill("SIGKILL");
  }
}