Tracker field relations and sorting selectable objects

$format = $this->trackerField->getOption('format');
        $sort = 'title_asc';
        if (! empty($format)) {
            if (preg_match('/\{(.*?)\}/', $format, $m)) {
                $sort = $m[1] . '_asc';
            }
        }

        $params = [
            'existing' => $data['value'],
            'relations' => $data['relations'],
            'meta' => json_encode($data['meta']),
            'filter' => $filter,
            'sort' => $sort,
            'format' => $format,
            'parent' => $this->trackerField->getOption('parentFilter'),
            'parentkey' => $this->trackerField->getOption('parentFilterKey'),
        ];

$sort = 'title_asc';

// First, check if sort is explicitly provided in filter
if (!empty($filter)) {
    // Check if $filter is already an array or needs parsing
    if (is_array($filter)) {
        $filterParams = $filter;
    } else {
        parse_str($filter, $filterParams);
        $filter = $filterParams; // Update $filter to be the array
    }
    
    if (!empty($filterParams['_sort'])) {
        // Use the sort directly from filter (already includes _asc or _desc)
        $sort = $filterParams['_sort'];
        // REMOVE _sort from filter array as it's handled separately
        unset($filterParams['_sort']);
        $filter = $filterParams;
    }
}

// If no sort in filter, derive from format
if ($sort === 'title_asc' && !empty($format)) {
    if (preg_match('/\{(.*?)\}/', $format, $m)) {
        $sort = $m[1] . '_asc';
    }
}


$params = [
    'existing' => $data['value'],
    'relations' => $data['relations'],
    'meta' => json_encode($data['meta']),
    'filter' => $filter,  // Pass as array WITHOUT _sort
    'sort' => $sort,      // Sort is passed separately
    'format' => $format,
    'parent' => $this->trackerField->getOption('parentFilter'),
    'parentkey' => $this->trackerField->getOption('parentFilterKey'),
];