public function send($url, $method = 'GET', $data = null, callable $callback = null)
    {
        $this->curl($url);
        $this->setDefaultOptions();

        if (is_array($this->options))
        {
            if (count($this->options) > 0)
            {
                foreach ($this->options as $key => $value)
                {
                    $this->setOption($key, $value);
                }
            }
        }

        if ($method !== self::GET)
        {
            $this->method($method);
        }

        if ($method === self::POST || $method === self::PUT || $method === self::DELETE)
        {
            $this->setOption(CURLOPT_POSTFIELDS, $data);
        }

        $response = $this->execute();

        if (!$response)
        {
            $this->error();
        }

        $this->getInfo();
        $this->close();

        if ( is_callable($callback) )
        {
            $callback($this->response, $this->info, $this->errors);
        }

        return $response;
    }