import { createHash, randomBytes } from "node:crypto";
import { cookies } from "next/headers";
import { redirect } from "next/navigation";
import { db } from "./db";

const COOKIE = "kibu_session";
export const tokenHash = (token: string) => createHash("sha256").update(token).digest("hex");
export type Staff = { id: string; email: string; name: string };

export async function currentStaff(): Promise<Staff | null> {
  const token = (await cookies()).get(COOKIE)?.value;
  if (!token || !/^[a-f0-9]{64}$/.test(token)) return null;
  const result = await db.query<Staff>(
    `SELECT s.id, s.email, s.name FROM sessions t JOIN staff s ON s.id = t.staff_id
     WHERE t.token_hash = $1 AND t.expires_at > now()`, [tokenHash(token)],
  );
  return result.rows[0] ?? null;
}

export async function requireStaff() {
  const staff = await currentStaff();
  if (!staff) redirect("/login");
  return staff;
}

export async function createSession(staffId: string) {
  const token = randomBytes(32).toString("hex");
  const expires = new Date(Date.now() + 12 * 60 * 60 * 1000);
  await db.query("DELETE FROM sessions WHERE expires_at <= now()");
  await db.query("INSERT INTO sessions(token_hash, staff_id, expires_at) VALUES ($1, $2, $3)",
    [tokenHash(token), staffId, expires]);
  (await cookies()).set(COOKIE, token, {
    httpOnly: true, sameSite: "lax", secure: process.env.SESSION_SECURE === "true",
    path: "/", expires,
  });
}

export async function deleteSession() {
  const jar = await cookies();
  const token = jar.get(COOKIE)?.value;
  if (token) await db.query("DELETE FROM sessions WHERE token_hash = $1", [tokenHash(token)]);
  jar.delete(COOKIE);
}