class Time

class Time implements TimeInterface {
    
    /**
     * The request stack.
     */
    protected ?RequestStack $requestStack;
    
    /**
     * A proxied request time if the request time is not available.
     */
    protected float $proxyRequestTime;
    
    /**
     * Constructs a Time object.
     *
     * @param \Symfony\Component\HttpFoundation\RequestStack|null $request_stack
     *   (Optional) The request stack.
     */
    public function __construct(?RequestStack $request_stack = NULL) {
        $this->requestStack = $request_stack;
    }
    
    /**
     * {@inheritdoc}
     */
    public function getRequestTime() {
        $request = $this->requestStack ? $this->requestStack
            ->getCurrentRequest() : NULL;
        if ($request) {
            return $request->server
                ->get('REQUEST_TIME');
        }
        // If this is called prior to the request being pushed to the stack fallback
        // to built-in globals (if available) or the system time.
        return $_SERVER['REQUEST_TIME'] ?? $this->getProxyRequestTime();
    }
    
    /**
     * {@inheritdoc}
     */
    public function getRequestMicroTime() {
        $request = $this->requestStack ? $this->requestStack
            ->getCurrentRequest() : NULL;
        if ($request) {
            return $request->server
                ->get('REQUEST_TIME_FLOAT');
        }
        // If this is called prior to the request being pushed to the stack fallback
        // to built-in globals (if available) or the system time.
        return $_SERVER['REQUEST_TIME_FLOAT'] ?? $this->getProxyRequestMicroTime();
    }
    
    /**
     * {@inheritdoc}
     */
    public function getCurrentTime() {
        return time();
    }
    
    /**
     * {@inheritdoc}
     */
    public function getCurrentMicroTime() {
        return microtime(TRUE);
    }
    
    /**
     * Returns a mimic of the timestamp of the current request.
     *
     * @return int
     *   A value returned by time().
     */
    protected function getProxyRequestTime() : int {
        if (!isset($this->proxyRequestTime)) {
            $this->proxyRequestTime = $this->getCurrentMicroTime();
        }
        return (int) $this->proxyRequestTime;
    }
    
    /**
     * Returns a mimic of the timestamp of the current request.
     *
     * @return float
     *   A value returned by microtime().
     */
    protected function getProxyRequestMicroTime() : float {
        if (!isset($this->proxyRequestTime)) {
            $this->proxyRequestTime = $this->getCurrentMicroTime();
        }
        return $this->proxyRequestTime;
    }

}