Restrict custom field to product variant

<?php
/**
 * @package	HikaShop for Joomla!
 * @version	5.1.5
 * @author	hikashop.com
 * @copyright	(C) 2010-2025 HIKARI SOFTWARE. All rights reserved.
 * @license	GNU/GPLv3 http://www.gnu.org/licenses/gpl-3.0.html
 */
defined('_JEXEC') or die('Restricted access');

$cart = $this->checkoutHelper->getCart();
if(!hikashop_level(2)) {
	$this->emptyBlocksCount++;
	return;
}

// Check wheather there is products 78 or 79 in cart
$target_ids = array(78, 79);
$found = false;
if (!empty($cart->products) && is_array($cart->products)) {
	foreach ($cart->products as $product) {
		if (in_array((int)$product->product_id, $target_ids)) {
			$found = true;
			break;
		}
	}
}

$fields = null;
if (!empty($cart->order_fields)) {
    $fields = hikashop_copy($cart->order_fields);
}

// If there are none of products 78 or 79 in cart we hide field "sleepwith" 
if (!$found && !empty($fields)) {
	foreach ($fields as $k => $field) {
		if (isset($field->field_namekey) && $field->field_namekey === 'sleepwith') {
			unset($fields[$k]); // Pašalina tik "sleepwith" lauką
			break;
		}
	}
}

// If there is 78 or 79 in cart, make "sleepwith" field reguired
if ($found && !empty($fields)) {
	foreach ($fields as $k => $field) {
		if (isset($field->field_namekey) && $field->field_namekey === 'sleepwith') {
			$field->field_required = 1; // Padarome lauką privalomu
			break;
		}
	}
}

$labelcolumnclass = 'hkc-sm-4';
$inputcolumnclass = 'hkc-sm-8';

if(empty($this->ajax)) {
?>
<div id="hikashop_checkout_fields_<?php echo $this->step; ?>_<?php echo $this->module_position; ?>" data-checkout-step="<?php echo $this->step; ?>" data-checkout-pos="<?php echo $this->module_position; ?>" class="hikashop_checkout_fields">
<?php } ?>
	<div class="hikashop_checkout_loading_elem"></div>
	<div class="hikashop_checkout_loading_spinner"></div>

<?php
	$this->checkoutHelper->displayMessages('fields');
?>
<fieldset class="hkform-horizontal">
<?php
	if(!empty($fields)) {
		if(!empty($this->options['show_title'])) {
?>
	<legend><?php echo JText::_('ADDITIONAL_INFORMATION'); ?></legend>
<?php
		}
		$after = array();
		foreach($fields as $fieldName => $oneExtraField) {
			$oneExtraField->registration_page = @$this->registration_page;
			if(isset($_SESSION['hikashop_order_data']) && is_object($_SESSION['hikashop_order_data']) && isset($_SESSION['hikashop_order_data']->$fieldName) && !is_null($_SESSION['hikashop_order_data']->$fieldName)) {
				$element = $_SESSION['hikashop_order_data'];
			} else {
				$element = $cart->cart_fields;
			}
			$value = @$element->$fieldName;

			if(empty($value) && !empty($this->options['read_only']))
				continue;

			if(empty($this->options['read_only'])) {
				$onWhat = ($oneExtraField->field_type == 'radio') ? 'onclick' : 'onchange';
				$html = $this->fieldClass->display(
					$oneExtraField,
					$value,
					'data[order_' . $this->step . '_' . $this->module_position.']['.$fieldName.']',
					false,
					' class="'.HK_FORM_CONTROL_CLASS.'" '.$onWhat.'="window.hikashop.toggleField(this,\''.$fieldName.'\',\'order_' . $this->step . '_' . $this->module_position.'\',0,\'hikashop_\');"',
					false,
					$fields,
					$cart->cart_fields,
					false
				);
				if($oneExtraField->field_type == 'hidden') {
					$after[] = $html;
					continue;
				}
			}else{
				$oneExtraField->currentElement = $element;
				$html = $this->fieldClass->show($oneExtraField, $value);
			}
?>
	<div class="hkform-group control-group hikashop_checkout_<?php echo $fieldName;?>_line" id="hikashop_order_<?php echo $this->step . '_' . $this->module_position . '_' . $oneExtraField->field_namekey; ?>">
<?php
			$requiredDisplay = true;
			if(!empty($this->options['read_only'])) {
				$requiredDisplay = false;
			}
			$label =  $this->fieldClass->getFieldName($oneExtraField, $requiredDisplay, $labelcolumnclass.' hkcontrol-label');
			if(!empty($this->options['read_only'])) {
				$label = str_replace('</label>',' :</label>',$label);
			}
			echo $label;
?>
		<div class="<?php echo $inputcolumnclass;?>">
<?php
			echo $html;
?>
		</div>
	</div>
<?php
		}
		if(count($after)) {
			echo implode("\r\n", $after);
		}
		if(!empty($this->options['show_submit'])) {
?>
	<div class="hkform-group control-group hikashop_fields_button_line">
		<div class="<?php echo $labelcolumnclass;?> hkcontrol-label"></div>
		<div class=" <?php echo $inputcolumnclass;?>">
			<button type="submit" onclick="return window.checkout.submitFields(<?php echo $this->step.','.$this->module_position; ?>);" class="<?php echo $this->config->get('css_button','hikabtn'); ?> hikabtn_checkout_fields_submit">
				<?php echo JText::_('HIKA_SUBMIT_FIELDS'); ?>
			</button>
		</div>
	</div>
<?php
		}
	} else {
		$this->emptyBlocksCount++;
	}
?>
</fieldset>
<?php
	if(!empty($this->options['js'])) {
?>
<script type="text/javascript">
<?php echo $this->options['js']; ?>
</script>
<?php
	}
	if(empty($this->ajax)) { ?>
</div>
<script type="text/javascript">
if(!window.checkout) window.checkout = {};
window.Oby.registerAjax(['checkout.fields.updated','cart.updated','checkout.shipping.changed','checkout.payment.changed'], function(params){
	window.checkout.refreshFields(<?php echo (int)$this->step; ?>, <?php echo (int)$this->module_position; ?>);
});
window.checkout.refreshFields = function(step, id) { return window.checkout.refreshBlock('fields', step, id); };

// make sure field is filled 
window.checkout.submitFields = function(step, id) {
	// Check weather "sleepwith" is fiiled if products 78 or 79 is in cart
	var sleepwithField = document.querySelector('[name="data[order_<?php echo $this->step; ?>_<?php echo $this->module_position; ?>][sleepwith]"]');
	if (sleepwithField && sleepwithField.value == "" && <?php echo $found ? 'true' : 'false'; ?>) {
		alert("Please fill this field");
		return false; // Stops if its empty
	}
	return window.checkout.submitBlock('fields', step, id);
};
</script>
<?php } ?>