How to get folders and their subfolders with their paths?

// data fetched from database, it's dynamic
$treeData = [
    ['id' => 1, 'name' => 'Root A', 'parent_id' => 0],
    ['id' => 2, 'name' => 'Child A', 'parent_id' => 1],
    ['id' => 3, 'name' => 'Grandchild A1', 'parent_id' => 2],
    ['id' => 4, 'name' => 'Grandchild A2', 'parent_id' => 2],
    ['id' => 5, 'name' => 'Child B', 'parent_id' => 1],
    ['id' => 6, 'name' => 'Root B', 'parent_id' => 0],
    ['id' => 7, 'name' => 'Root C', 'parent_id' => 0],
];

// Function to build the hierarchical array from flat data
function buildTree(array &$elements, $parentId = 0) {
    $branch = [];
    foreach ($elements as $element) {
        if ($element['parent_id'] == $parentId) {
            $children = buildTree($elements, $element['id']);
            if ($children) {
                $element['children'] = $children;
            }
            $branch[] = $element;
        }
    }
    return $branch;
}

// Build the hierarchical tree structure
$hierarchicalTree = buildTree($treeData);

i would like to get all the parents and children with their parent path in array as

$output = [
 'Root A',
 'Root A/Child A',
 'Root A/Child A/Grandchild A1',
 'Root A/Child A/Grandchild A2',
 'Root A/Child B',
 'Root B',
 'Root C'
];

I actual task is to create these folders and subfolders dynamically to new users created in my system i was following this answer in stackoverflow

Please try below code:

<?php

// Original flat data (from DB)
$treeData = [
    ['id' => 1, 'name' => 'Root A', 'parent_id' => 0],
    ['id' => 2, 'name' => 'Child A', 'parent_id' => 1],
    ['id' => 3, 'name' => 'Grandchild A1', 'parent_id' => 2],
    ['id' => 4, 'name' => 'Grandchild A2', 'parent_id' => 2],
    ['id' => 5, 'name' => 'Child B', 'parent_id' => 1],
    ['id' => 6, 'name' => 'Root B', 'parent_id' => 0],
    ['id' => 7, 'name' => 'Root C', 'parent_id' => 0],
];

// Step 1: Build tree structure
function buildTree(array &$elements, $parentId = 0) {
    $branch = [];
    foreach ($elements as $element) {
        if ($element['parent_id'] == $parentId) {
            $children = buildTree($elements, $element['id']);
            if ($children) {
                $element['children'] = $children;
            }
            $branch[] = $element;
        }
    }
    return $branch;
}

// Step 2: Build flat path list
function buildPaths(array $tree, string $parentPath = ''): array {
    $paths = [];

    foreach ($tree as $node) {
        $currentPath = $parentPath === '' ? $node['name'] : $parentPath . '/' . $node['name'];
        $paths[] = $currentPath;

        if (isset($node['children'])) {
            $childPaths = buildPaths($node['children'], $currentPath);
            $paths = array_merge($paths, $childPaths);
        }
    }

    return $paths;
}

// Build the hierarchical tree
$hierarchicalTree = buildTree($treeData);

// Get the output paths
$output = buildPaths($hierarchicalTree);

// Debug: print the output
print_r($output);

You can now loop over $output to dynamically create directories for each user, for example:

foreach ($output as $folderPath) {
    $fullPath = "/users/{$userId}/" . $folderPath;
    if (!is_dir($fullPath)) {
        mkdir($fullPath, 0777, true); // 'true' allows recursive directory creation
    }
}