How to set value in nested array PHP - php

Question

I would like to set level to each array that has children key in nested array. More deep that array then more big the level value.
Here's what I'm expected:
<?php
$array = array(
array(
'id' => 1,
'children' => array(
array(
'id' => 6,
'children' => array(
array(
'id' => 7,
),
array(
'id' => 8,
)
),
// Expected
'level' => '2',
),
array(
'id' => 9,
)
),
// Expected
'level' => '1'
),
array(
'id' => 2,
'children' => array(
array(
'id' => 10,
),
array(
'id' => 13,
'children' => array(
array(
'id' => 14,
),
array(
'id' => 19,
'children' => array(
array(
'id' => 20,
),
array(
'id' => 21,
),
array(
'id' => 22,
),
array(
'id' => 23,
),
)
// Expected
'level' => '3'
)
),
// Expected
'level' => '2'
),
),
// Expected
'level' => '1'
)
);
So far I make a function to set the level that has children key in nested array. But, the result is not what I'm expected.
<?php
$array = array(
array(
'id' => 1,
'children' => array(
array(
'id' => 6,
'children' => array(
array(
'id' => 7,
),
array(
'id' => 8,
)
),
// Expected
// 'level' => '2',
),
array(
'id' => 9,
)
),
// Expected
// 'level' => '1'
),
array(
'id' => 2,
'children' => array(
array(
'id' => 10,
),
array(
'id' => 13,
'children' => array(
array(
'id' => 14,
),
array(
'id' => 19,
'children' => array(
array(
'id' => 20,
),
array(
'id' => 21,
),
array(
'id' => 22,
),
array(
'id' => 23,
),
)
// Reality result
// 'level' => '4'
)
),
// Reality result
// 'level' => '3'
),
),
// Reality result
// 'level' => '2'
)
);
As you can see in Reality result comment is level 2, level 3, and level 4. What I'm expected the result is level 1, level 2, level 3, level (n+1). When there's not any children in the deeper array then the level value must be reset to level 1.
Here's my code that get the reality result:
<?php
function updateTreeArray(&$array, $level = 1) {
foreach ($array as $key => &$value) {
if (isset($value['children'])) {
$value['level'] = $level;
$level = setLevel($value['children'], $level);
}
if (is_array($value)) {
updateTreeArray($value, $level);
}
}
return $array;
}
function setLevel($array, $level) {
foreach ($array as $key => &$value) {
if (isset($value['children'])) {
$level += 1;
setLevel($value['children'], $level);
}
}
return $level;
}
print_r(updateTreeArray($array));
Could you please help me what should I do to achieve the expected result? Thanks.

Answer 1

One recursive function is enough.
function updateTreeArray(&$array, $level = 1)
{
foreach($array as &$item) {
if (array_key_exists('children', $item) && is_array($item['children'])) {
$item['level'] = $level;
updateTreeArray($item['children'], $level + 1);
}
}
}
updateTreeArray($array);
print_r($array);
fiddle