"use server";

import { cookies } from "next/headers";
import { revalidatePath } from "next/cache";

const WEEK_COOKIE = "tcWeek";
const MAX_AGE = 60 * 60 * 24 * 30; // 30 days

/**
 * Persist the selected week start (YYYY-MM-DD) in a server-readable cookie
 * and revalidate the home page so the new week renders.
 */
export async function setWeek(weekStart: string): Promise<void> {
  if (!/^\d{4}-\d{2}-\d{2}$/.test(weekStart)) return;
  const cookieStore = await cookies();
  cookieStore.set(WEEK_COOKIE, weekStart, {
    path: "/",
    maxAge: MAX_AGE,
    sameSite: "lax",
  });
  revalidatePath("/");
}

/** Clear the saved week — used by the "Today" button to jump back to current. */
export async function clearWeek(): Promise<void> {
  const cookieStore = await cookies();
  cookieStore.delete(WEEK_COOKIE);
  revalidatePath("/");
}