import { createHash, randomBytes, timingSafeEqual } from "node:crypto";
import type { FastifyRequest } from "fastify";

export const SESSION_COOKIE = "companion_session";
export const CSRF_COOKIE = "companion_csrf";

export function randomToken(bytes = 32): string {
  return randomBytes(bytes).toString("base64url");
}

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

export function safeEqual(left: string, right: string): boolean {
  const leftBuffer = Buffer.from(left);
  const rightBuffer = Buffer.from(right);
  return leftBuffer.length === rightBuffer.length && timingSafeEqual(leftBuffer, rightBuffer);
}

export function clientAddress(request: FastifyRequest): string {
  return request.ip.slice(0, 64);
}