Free Product with Purchase

I have products of specific categories set up. One is a main Membership category and the others have a category of Designation. When someone is on a membership form and they are purchasing a Membership product, they need to be able to purchase 1 or more Designation products. The First designation product they pick should be free, the others are all billed regular price. Is there a way to set this up without the user having to enter a coupon code?

Thank you, I was able to create a calculator that did what I need. But my site also uses a coupon code. Is there a way to ensure that my calculator runs AFTER the calculator for the coupon code?

I added the code to the site.php file and found my mistake, I was eliminating the coupon discount before looking to see if it exists.

This calculator checks the current date and if it's October - December, discounts the main membership item by 50%. It checks if there is already a coupon discount (which would be $25% off the membership) and then calculates 50% off that total before applying the end of year discount to the first charge.

It's important to know that for this website, all memberships go from 4/1 - 4/1. No matter what day they purchase their membership, it has to expire on 4/1 of the next year. This is why they get a 50% discount after October - The date is from the current date to 4/1 of the next year. If they purchase between January 1 and April 1, it goes from 01/01 of the current year until 4/1 of the next year (so they pay full price but get some extra months).

I have several other hooks in site.php that will update the access record dates and the invoice rebill date.

It then discounts the first Designation membership item 100%.

PHP:

Am_Di::getInstance()->hook->add('invoiceGetCalculators', 'FSGAinvoiceGetCalculators');

function FSGAinvoiceGetCalculators(Am_Event $e) {
    $vars = $e->getVars();
    $calculators = $e->getReturn();
    $calculators[] = new Am_Invoice_Calc_MemberDisc($this->vars);   
    $e->setReturn($calculators);

}

class Am_Invoice_Calc_MemberDisc extends Am_Invoice_Calc
{
    /** @var Coupon */
    protected $coupon;
    protected $user;
    protected $membership_count;
    protected $designation_count;   
    protected $designation_prods;
    //Product Category
    //  Designation = 3
    //  Membership = 1
    //  Membership Individual = 6
    //  Membership Organizational = 7
   
    public function productInCategory($category_id, $product_id){
        $rows = AM_di::getInstance()->db->query("SELECT product_id FROM ?_product_product_category
            WHERE product_category_id = ? and product_id = ?", $category_id, $product_id);
        return !empty($rows);
    }
    public function calculate(Invoice $invoiceBill)
    {
        $this->membership_count = $this->designation_count = 0;
        $this->user = $invoiceBill->getUser();
        $isFirstPayment = $invoiceBill->isFirstPayment();
        $first_discountable = $second_discountable = array();
        foreach ($invoiceBill->getItems() as $item) {
            $item->_calculateTotal();
            $month = date("n");
            $eoy_discount = false;
            if ($month >= 10) {$eoy_discount = true;}
            if ($eoy_discount) {
                if ($this->productInCategory(1, $item->item_id)) {               
                    $itemprice = $item->first_price;
                    $currentdiscount = $item->first_discount;
                    $currentprice = $itemprice - $currentdiscount;
                    $endprice = $currentprice * .5;
                    $memberdiscount = $itemprice - $endprice;
                    $item->first_discount = $memberdiscount;
                    $this->membership_count += 1;
    Am_Di::getInstance()->errorLogTable->log("price: ".$itemprice."Current Discount: ".$currentdiscount." Current Price: ".$currentprice." End Price: ".$endprice." Discount: ".$item->first_discount);               
                }
            }
                
            if ($this->productInCategory(3, $item->item_id)) {
                $this->designation_count += 1;
                $first_discountable[] = $item;
                $second_discountable[] = $item;
            }
        }               
        $discount_avail = $this->membership_count;
        if (!empty($first_discountable[1])) {
            if ($discount_avail >= 1) {
                $item = $first_discountable[1];
                $discount = $item->first_price;
                if ($discount_avail == 1) {
                    $discount_avail = 0;                       
                }
                $item->first_discount = $discount;
                $item->second_discount = $discount;
            }
        }
       
        foreach ($invoiceBill->getItems() as $item) {
            $item->_calculateTotal();
        }
    }
}


Yes, I found the error in my code. This line:

Code:

$this->membership_count = $this->designation_count = 0;

was zeroing out the coupon discount. Once I removed that line of code it did what I needed it to do.

Thanks for your help.