import { randomBytes } from 'node:crypto';
import type { IncomingMessage } from 'node:http';

export const RENDERER_CAPABILITY_HEADER = 'x-niancode-renderer-capability';

let rendererCapability = '';

export function rotateRendererCapability(): void {
  rendererCapability = randomBytes(32).toString('hex');
}

export function getRendererCapability(): string {
  return rendererCapability;
}

export function hasRendererCapability(req: IncomingMessage): boolean {
  const value = req.headers[RENDERER_CAPABILITY_HEADER];
  return typeof value === 'string'
    && rendererCapability.length > 0
    && value === rendererCapability;
}