private function processFile($filePath, $group = null, $baseDir = null)
    {
        if (is_null($baseDir)) {
            $baseDir = $this->baseDirectory;
        }
        if ( ! is_string($baseDir)) {
            $baseDir = '';
        }
        if ($baseDir) {
            $baseDir = rtrim($baseDir, '/').'/';
        }
        $content = $this->findAndParseFile($baseDir.$filePath);
        if (empty($content)) {
            return null;
        }
        if (is_null($group)) {
            $fileNameBase = $this->extractFileNameBase($filePath);
            if ('config' === strtolower($fileNameBase)) {
                $group = false;
            } else {
                $group = $fileNameBase;
            }
        } elseif (true === $group) {
            $fileNameBase = $this->extractFileNameBase($filePath);
            $group = $fileNameBase;
        }
        if ($group) {
            $result = array($group => $content);
        } else {
            $result = $content;
        }
        return $result;
    }