Method getRandomImageRecursive

/*
 * RANDOM IMAGE OR IMAGE ORDERED BY PARAM - CATEGORIES VIEW, CATEGORY VIEW
 * $extImage - for example Picasa image
 * $extImageSize - 1 - small, 2 - medium, 3 - large
 * Is called random but the ordering can be set
 */
public static function getRandomImageRecursive($categoryid, $categoryImageOrdering = '', $extImage = 0, $extImageSize = 1)
{
    $db = Factory::getDBO();
    $user = Factory::getUser();
    $image = new stdClass();
    if (!is_array($categoryImageOrdering) && is_numeric($categoryImageOrdering)) {
        $categoryImageOrdering = PhocaGalleryOrdering::getOrderingString($categoryImageOrdering);
    }
    // We need to get a list of all subcategories in the given category
    if ($categoryImageOrdering['column'] == '') {
        $ordering = $orderingRandomCat = ' ORDER BY RAND()';
    } else {
        // This is special case where we change category to image
        $ordering = ' ORDER BY a.' . $categoryImageOrdering['column'] . ' ' . $categoryImageOrdering['sort'];
        $orderingRandomCat = ' ORDER BY c.ordering';
        //TO DO - can be changed to category_ordering parameter
    }
    $query = 'SELECT a.id, a.filename, a.exts, a.extm, a.extw, a.exth, a.extid, c.accessuserid as cataccessuserid, c.access as cataccess' . ' FROM #__phocagallery AS a' . ' LEFT JOIN #__phocagallery_categories AS c ON a.catid = c.id' . ' WHERE a.catid = ' . (int) $categoryid . ' AND a.published = 1' . ' AND a.approved = 1' . $ordering . ' LIMIT 0,1';
    $db->setQuery($query);
    $images = $db->loadObjectList();
    // Test the user rights to display random image as category image
    $rightDisplay = 1;
    //default is set to 1 (all users can see the category)
    if (isset($images[0]->cataccessuserid) && isset($images[0]->cataccess)) {
        $rightDisplay = PhocaGalleryAccess::getUserRight('accessuserid', $images[0]->cataccessuserid, $images[0]->cataccess, $user->getAuthorisedViewLevels(), $user->get('id', 0), 0);
    }
    if ($rightDisplay == 0) {
        $images = array();
    }
    if (!isset($images) || empty($images)) {
        $image->exts = '';
        $image->extm = '';
        $image->exth = '';
        $image->extw = '';
        $image->filename = '';
        // TO DO, if we find no image in subcategory we look at its subcategory (subcategory of subcategory)
        // no to look if there is some subcategory on the same level
        $subCategories = PhocaGalleryImageFront::getRandomCategory($categoryid, $ordering);
        foreach ($subCategories as $subCategory) {
            $image = PhocaGalleryImageFront::getRandomImageRecursive($subCategory->id, $categoryImageOrdering, $extImage, $extImageSize);
            // external image - e.g. Picasa
            if ($extImage == 1) {
                if ($extImageSize == 2) {
                    if (isset($image->extm) && $image->extm != '') {
                        break;
                    }
                } else {
                    if (isset($image->exts) && $image->exts != '') {
                        break;
                    }
                }
            } else {
                if (isset($image->filename) && $image->filename != '') {
                    break;
                }
            }
        }
    } else {
        $image = $images[0];
    }
    if ($extImage == 1) {
        return $image;
    } else {
        if (isset($image->filename)) {
            return $image->filename;
        } else {
            return $image;
        }
    }
}