import { sha256Hex } from "@/worker/auth/crypto";

export function clientIp(request: Request): string | null {
  const forwardedFor = request.headers.get("x-forwarded-for")?.split(",")[0]?.trim();
  return request.headers.get("cf-connecting-ip") ?? forwardedFor ?? request.headers.get("x-real-ip") ?? null;
}

export async function hashNullable(value: string | null | undefined): Promise<string | null> {
  return value ? await sha256Hex(value) : null;
}

export function pathPrefix(pathname: string): string {
  const segment = pathname.split("/").filter(Boolean)[0];
  return segment ? `/${segment}` : "/";
}

export function destinationHost(request: Request): string | null {
  const destination = request.headers.get("destination");
  if (!destination) return null;
  try {
    return new URL(destination).host;
  } catch {
    return null;
  }
}