import { one } from '../db.js';

export type AppRole = 'admin' | 'moderator' | 'user';

/** Reimplements public.has_role(uuid, app_role). */
export async function hasRole(userId: string, role: AppRole): Promise<boolean> {
  const row = await one<{ exists: boolean }>(
    `SELECT EXISTS (SELECT 1 FROM public.user_roles WHERE user_id = $1 AND role = $2) AS exists`,
    [userId, role]
  );
  return !!row?.exists;
}

/** Reimplements public.get_user_role(uuid). Returns null if none. */
export async function getUserRole(userId: string): Promise<AppRole | null> {
  const row = await one<{ role: AppRole }>(
    `SELECT role FROM public.user_roles WHERE user_id = $1 LIMIT 1`,
    [userId]
  );
  return row?.role ?? null;
}

/** Reimplements public.no_admin_exists(). */
export async function noAdminExists(): Promise<boolean> {
  const row = await one<{ exists: boolean }>(
    `SELECT NOT EXISTS (SELECT 1 FROM public.user_roles WHERE role = 'admin') AS exists`
  );
  return !!row?.exists;
}