aff.php

<?php
/**
 * Affiliate Cookie Tracking + Redirection Handler
 *
 * @package    WHMCS
 * @author     WHMCS Limited <development@whmcs.com>
 * @copyright  Copyright (c) WHMCS Limited 2005-2018
 * @license    https://www.whmcs.com/license/ WHMCS Eula
 * @version    $Id$
 * @link       https://www.whmcs.com/
 */

use WHMCS\Affiliate\Referrer;
use WHMCS\Carbon;
use WHMCS\Cookie;

define("CLIENTAREA",true);

require("init.php");

// if affiliate id is present, update visitor count & set cookie
if ($aff = $whmcs->get_req_var('aff')) {
    update_query("tblaffiliates",array("visitors"=>"+1"),array("id"=>$aff));
    Cookie::set('AffiliateID',$aff,'3m');

    $referrer = trim($_SERVER['HTTP_REFERER']);
    Referrer::firstOrCreate([
        'affiliate_id' => $aff,
        'referrer' => $referrer,
    ])->hits()->create([
        'affiliate_id' => $aff,
        'created_at' => Carbon::now()->toDateTimeString(),
    ]);

}

/**
 * Executes when a user has clicked an affiliate referral link.
 *
 * @param int $affiliateId The unique id of the affiliate that the link belongs to
 */
run_hook("AffiliateClickthru", array(
    'affiliateId' => $aff,
));

// if product id passed in, redirect to order form
if ($pid = $whmcs->get_req_var('pid')) redir("a=add&pid=".(int)$pid,"cart.php");

// if product group id passed in, redirect to product group
if ($gid = $whmcs->get_req_var('gid')) redir("gid=".(int)$gid,"cart.php");

// if register = true, redirect to registration form
if ($whmcs->get_req_var('register')) redir("","register.php");

// if gocart = true, redirect to cart with request params
if ($whmcs->get_req_var('gocart')) {
    $reqvars = '';
    foreach ($_GET AS $k=>$v) $reqvars .= $k.'='.urlencode($v).'&';
    redir($reqvars,"cart.php");
}

// perform redirect
header("HTTP/1.1 301 Moved Permanently");
header("Location: ".$whmcs->get_config('Domain'),true,301);