disable variants for sold out articles #shopware

Bootstrap.php

<?php
class Shopware_Plugins_Frontend_GlassesStockVariant_Bootstrap extends Shopware_Components_Plugin_Bootstrap {
    public function getCapabilities() {
        return array(
            'install' => true,
            'update' => true,
            'enable' => true
        );
    }
 
    public function getLabel() {
        return 'Varianten deaktivieren bei ungenügendem Lagerbestand';
    }
 
    public function getVersion() {
        return '1.0.0';
    }
 
    public function getInfo() {
        return array(
            'version' => $this->getVersion(),
            'label' => $this->getLabel(),
            'author' => 'David Vielhuber',
            'supplier' => 'David Vielhuber',
            'description' => 'Varianten deaktivieren bei ungenügendem Lagerbestand',
            'support' => 'David Vielhuber',
            'link' => 'https://vielhuber.de'
        );
    } 
 
    public function install() {
        $this->registerEvents(); 
        return array('success' => true, 'invalidateCache' => array('frontend'));
    }
     
    public function registerEvents() {
        $this->subscribeEvent(
            'Shopware_Modules_Order_SendMail_BeforeSend',
            'disable_sold_out_variants'
        );
    }
    
    public function disable_sold_out_variants(Enlight_Event_EventArgs $args) {
        // Loop through articles
        $article = Shopware()->Db()->fetchAll("SELECT * FROM s_order_details WHERE ordernumber = ?", array($args->getSubject()->sOrderNumber));
        foreach($article as $a) {            
		// Get current stock of this variant
		$instock = Shopware()->Db()->fetchOne("SELECT instock FROM s_articles_details WHERE articleID = ? AND ordernumber = ?", array($a["articleID"], $a["articleordernumber"]));
		// If stock is leq 0, set to inactive
		if($instock <= 0) {
			Shopware()->Db()->query("UPDATE s_articles_details SET active = ? WHERE articleID = ? AND ordernumber = ?", array(0,$a["articleID"],$a["articleordernumber"]));
		}     
		// If all variants are inactive, set main article inactive
		$count_active = Shopware()->Db()->fetchOne("SELECT COUNT(ID) FROM s_articles_details WHERE articleID = ? AND active = ?", array($a["articleID"],1));
		if($count_active == 0) {
			Shopware()->Db()->query("UPDATE s_articles SET active = ? WHERE ID = ?", array(0,$a["articleID"]));
		}
        }    
    }
}
?>