ensureDirectoryExists

function ensureDirectoryExists($filePath) {
        $pathSegments = array();

        $slashPosition = 0;
        $finished = false;

        while ($finished === false) {

            $slashPosition = mb_strpos($filePath, '/', $slashPosition + 1);

            if ($slashPosition === false) {
                $finished = true;
            }
            else {
                $pathSegments[] = mb_substr($filePath, 0, $slashPosition);
            }

            $maxPaths = 20;
            if (count($pathSegments) > $maxPaths) {
                throw new \Exception("Trying to create a directory more than $maxPaths deep. What is wrong with you?");
            }
        }

        foreach ($pathSegments as $segment) {
            if (file_exists($segment) === false) {
                //echo "Had to create directory $segment";
                $result = mkdir($segment);

                if ($result == false) {
                    throw new \Exception("Failed to create segment [$segment] in ensureDirectoryExists($filePath).");
                }
            }
        }

        return true;
    }