Nested array, replace alphabetical keys with numeric and keep structure

Question

I have a nested array who is 4 levels deep.

I would like to replace the keys by numerical ones but not the meta level, this array should keep the alphabetical keys.

The array will have a lot of values and there will be more accounts like Marco Mueller, this is just a short example. It is important that it will keep the same nested structure, after its replaced by numerical keys.

$array = array (
    'Marco Mueller' =>
        array (
            'meta' =>
                array (
                    'accountName' => 'Marco Mueller',
                    'accountId' => '1',
                    'sum' => '3,659.06',
                ),
            'Conrad, Ute' =>
                array (
                    'meta' =>
                        array (
                            'customerName' => 'Conrad, Ute',
                            'customerId' => '8391',
                            'sum' => '457.59',
                        ),
                    'Fidor Bank' =>
                        array (
                            'meta' =>
                                array (
                                    'bankName' => 'Fidor Bank',
                                    'bankKey' => 'FID',
                                    'sum' => '457.59',
                                ),
                            'H1-2019' =>
                                array (
                                    'meta' =>
                                        array (
                                            'periodName' => 'H1-2019',
                                            'periodId' => '5',
                                            'sum' => '457.59',
                                        ),
                                ),
                        ),
                ),
        ),
);

The result should be

$array = array (
        array (
            'meta' =>
                array (
                    'accountName' => 'Marco Mueller',
                    'accountId' => '1',
                    'sum' => '3,659.06',
                ),
             'items' => array (
                    'meta' =>
                        array (
                            'customerName' => 'Conrad, Ute',
                            'customerId' => '8391',
                            'sum' => '457.59',
                        ),
                     'items' => 
                           array (
                               'meta' =>
                                   array (
                                    'bankName' => 'Fidor Bank',
                                    'bankKey' => 'FID',
                                    'sum' => '457.59',
                                   ),
                                'items' => array (
                                    'meta' =>
                                        array (
                                            'periodName' => 'H1-2019',
                                            'periodId' => '5',
                                            'sum' => '457.59',
                                        ),
                                ),
                            ),

                            array (
                                    'meta' =>
                                        array (
                                            'periodName' => 'H2-2019',
                                            'periodId' => '6',
                                            'sum' => '600',
                                        ),
                                ),
                           ),
                ),
        ),
);

Answer 1

I solved my problem with this function, if anyone has an idea how to make this more elegant and efficient, your welcome!

private function getValues(array $array)
    {
        $newArray = [];
        foreach ($array as $item) {
            $meta = $item['meta'];
            unset($item['meta']);

            $arrayValues = array_values($item);

            if (count($arrayValues) > 1 || count($arrayValues[0]) > 1) {
                $arrayValues = $this->getValues($arrayValues);
            }

            if (!$arrayValues) {
                $values = [
                    'meta' => $meta,
                ];
            } else {
                $values = [
                    'meta' => $meta,
                    'items' => $arrayValues,
                ];
            }

            $newArray[] = $values;


        }

        return $newArray;
    }