Backend\Modules\Extensions\Engine\Model::validateThemeInformation PHP Method

    public static function validateThemeInformation($information)
    {
        // set default thumbnail if not sets
        if (!$information['thumbnail']) {
            $information['thumbnail'] = 'thumbnail.png';
        }
        // check if there are templates
        if (isset($information['templates']) && $information['templates']) {
            foreach ($information['templates'] as $i => $template) {
                if (!isset($template['label']) || !$template['label'] || !isset($template['path']) || !$template['path'] || !isset($template['format']) || !$template['format']) {
                    unset($information['templates'][$i]);
                    continue;
                }
                // if there are no positions we should continue with the next item
                if (!isset($template['positions']) && $template['positions']) {
                    continue;
                }
                // loop positions
                foreach ($template['positions'] as $j => $position) {
                    if (!isset($position['name']) || !$position['name']) {
                        unset($information['templates'][$i]['positions'][$j]);
                        continue;
                    }
                    // ensure widgets are well-formed
                    if (!isset($position['widgets']) || !$position['widgets']) {
                        $information['templates'][$i]['positions'][$j]['widgets'] = array();
                    }
                    // ensure editors are well-formed
                    if (!isset($position['editors']) || !$position['editors']) {
                        $information['templates'][$i]['positions'][$j]['editors'] = array();
                    }
                    // loop widgets
                    foreach ($position['widgets'] as $k => $widget) {
                        // check if widget is valid
                        if (!isset($widget['module']) || !$widget['module'] || !isset($widget['action']) || !$widget['action']) {
                            unset($information['templates'][$i]['positions'][$j]['widgets'][$k]);
                            continue;
                        }
                    }
                }
                // check if there still are valid positions
                if (!isset($information['templates'][$i]['positions']) || !$information['templates'][$i]['positions']) {
                    return;
                }
            }
            // check if there still are valid templates
            if (!isset($information['templates']) || !$information['templates']) {
                return;
            }
        }
        return $information;
    }