[Plugin: WP User Frontend] i try to add some errors on meta in add-post.php

Hi,

Thank you for your great plugins.

I try to add a function since some days on special meta and before the line 221 in wpfu-add-post.php

i desire to create a function to test some new meta in new custom field created with wpfu and to verify if a shortened link exist on my installation of yourls but i don’t understand what happens and how to hack lightly your code without i make a bug

$shortend = trim( strip_tags( $_POST[$fiels['cf_shortend']] ) );
    $longurl = trim( strip_tags( $_POST[$fiels['cf_longurl']] ) );

	if( (empty( $shortend )) ) {
        $errors[] = "No ending link selected";
    }
	if( (preg_match('#^\/#', $shortend )) ) {
        $errors[] = "No trailing slash please";
    }
	if( (preg_match('#^http:\/\/#', $shortend )) ) {
        $errors[] = "Just the end please after ".$dom."";
    }
	if( (empty( $longurl )) ) {
        $errors[] = "No long url selected to make shortened";
    }
	else{
    //var_dump( $_POST ); die();

		$dom = 'domain.tld';
		$url = ''.$dom.'/'.$shortend.'';
		$format = 'json';
		$api_url = ''.$domain.'/yourls-api.php';
		require_once(dirname(__FILE__).'/jssec.php');

		// Init the CURL session
		$ch = curl_init();
		curl_setopt($ch, CURLOPT_URL, $api_url);
		curl_setopt($ch, CURLOPT_HEADER, 0);            // No header in the result
		curl_setopt($ch, CURLOPT_RETURNTRANSFER, true); // Return, do not echo result
		curl_setopt($ch, CURLOPT_POST, 1);              // This is a POST request
		curl_setopt($ch, CURLOPT_POSTFIELDS, array(     // Data to POST
				'timestamp' => $timestamp,
				'signature' => $signature,
				'url'  		=> $longurl,
				'keyword'	=> $short,
				'format'    => $format,
				'action'    => 'shorturl'
			));

		// Fetch and return content
		$apinegoce = curl_exec($ch);
		curl_close($ch);

			if (!$apinegoce)
			{
				$errors[] = "Shortener services is on maintenance actually."; //if in Maintenance
			}
			else
			{
				// Do something with the result.
				$recho = json_decode($apinegoce, true);
				// Process data
				$ggstatus = $recho['statusCode'];

				if($ggstatus = '200'){}
				else{
						$errors[] = "A shortener link exist with this shortened. Please choose another one.";
						$errors[] = ''.$apinegoce.'';
					}
			}
		}
    } //is_array

https://www.ads-software.com/extend/plugins/wp-user-frontend/