questions/30299576/build-paths-of-all-paths-of-a-tree-struct

<?php // http://stackoverflow.com/questions/30299576/build-paths-of-all-paths-of-a-tree-structured-array-in-php

$tree = Array(
0 => Array(
        "name" => 'Furniture',
        "slug" => 'furniture',
        "children" => Array(
                "0" => Array
                    (
                        "name" => 'Sofa',
                        "slug" => 'sofa',
                        "leafs" => Array
                            (
                               "0" => Array ( "name" => '3 Seater', "slug" => '3-seater'),
                               "1" => Array ( "name" => '4 Seater', "slug" => '4-seater'),
                            ),

                    ),

                "1" => Array
                    (
                        "name" => 'Chairs',
                        "slug" => 'chairs',
                        "leafs" => Array
                            (
                               "0" => Array ( "name" => '3 Seater', "slug" => '3-seater'),
                               "1" => Array ( "name" => '4 Seater', "slug" => '4-seater'),
                            )

                    )

            )

    ),

1 => Array(
        "name" => 'Furniture1',
        "slug" => 'furniture1',
        "children" => Array(
                "0" => Array(
                        "name" => 'Sofa1',
                        "slug" => 'sofa1',
                        "leafs" => Array(
                               "0" => Array ( "name" => '3 Seater1', "slug" => '3-seater1'),
                               "1" => Array ( "name" => '4 Seater1', "slug" => '4-seater1'),
                            )

                    ),

                "1" => Array(
                        "name" => 'Chairs1',
                        "slug" => 'chairs1',
                        "leafs" => Array(
                               "0" => Array ( "name" => '3 Seater1', "slug" => '3-seater1'),
                               "1" => Array ( "name" => '4 Seater1', "slug" => '4-seater1')
                            )
                    )
            )
    )
);


echo '<pre>';
print_r($tree);
echo '</pre>';

/* --------------------------------------------------------------------------
 *  Run the program
 */

// This really should be class. Later...

/* -------------------------------------
 * Store all the paths in here...
 */
$allPaths = array();

/* -------------------------------------
 * The 'current' path to the leaf node
 *
 * This is a 'stack'. The 'path' is all the entries combined.
 *
 * @var array
 */
$currentPath = array(); // this is a 'stack'

walkTree($allPaths,       // reference
         $currentPath,    // reference
         $tree,
         'children',

         /**
          * The closure that is run for each 'leaf' node only currently
          * It could be called on every node if required.
          *
          * @param array currentPath to this value
          * @param array node - the actual leaf data
          * @param string nodeType - leaf or children
          */
         function(array $currentPath,
                   $node,
                   $nodeType = 'leaf')  {
            $fullPath = '';
//            var_dump(__FILE__.__LINE__, 'closure start:',  $node);

            if ($nodeType === 'leaf') {
                $fullPath = 'path: '. implode(' / ', $currentPath)
                           .' item: '. $node['name'];
            }
            return $fullPath;
        }
);

var_dump(__FILE__.__LINE__, $allPaths);

// ----------------------------- end of processing ---------------------------
exit;

/*
 * This takes the entire `current tree state` and decides what to do with the current node.
 */

/**
 * Apply processing to the current node.
 *
 * @param array $allPaths    -- added to by the 'processNode' closure
 * @param array $currentPath -- the full path to the current data
 * @param array $nodeList    -- all the descendants from this node
 * @param string $nodeListType 'children' or 'leaf'
 * @param closure $processNode -- called to process the current node data
 *                              -- needs the full path to the current node
 * @return void This is all 'side effects'
 */
function walkTree(&$allPaths,
                   &$currentPath,
                   $nodeList,
                   $nodeListType,
                   /* closure */ $processNode)
{
//    var_dump(__FILE__.__LINE__,
//             $currentPath,
//             $nodeList,
//             $nodeListType
//            );

    foreach ($nodeList as $key => $nodeValue) {

        if ($nodeListType === 'leaf') {
            $allPaths[] = $processNode($currentPath, $nodeValue, $nodeListType);
            continue; // will not recurse again from here.
        }

        // this must happen always...
//        var_dump('before processing one node: pushed: '. $nodeValue['name'], $currentPath);
        array_push($currentPath, $nodeValue['name']);

        if (isset($nodeValue['children'])) {
            $nodeType = 'children';
            $nodeList = $nodeValue['children'];
        }
        else {
            $nodeType = 'leaf';
            $nodeList = $nodeValue['leafs'];
        }

        walkTree($allPaths,
                 $currentPath,
                 $nodeList,
                 $nodeType,
                 $processNode);

        $name = array_pop($currentPath);
  //      var_dump('after processing one node: popped: '. $name, $currentPath);
    } // end of current list
    return;
}