import { createHash, timingSafeEqual } from "node:crypto";

export function hashToken(token: string): Buffer {
  return createHash("sha256").update(token, "utf8").digest();
}

export function safeTokenEqual(actual: string, expected: string): boolean {
  return timingSafeEqual(hashToken(actual), hashToken(expected));
}

export function shortHash(token: string): string {
  return hashToken(token).toString("hex").slice(0, 12);
}

export function extractBearer(headerValue: string | undefined | null): string | null {
  if (!headerValue || typeof headerValue !== "string") return null;
  const m = /^Bearer\s+(.+)$/i.exec(headerValue.trim());
  return m ? m[1] : null;
}