modx-evo-trees.php

<?php
if( ! function_exists('pPrint') ) {
    function pPrint($arr, $return = false){
        $output = '<pre>'.print_r($arr, TRUE).'</pre>';
        if ($return)
            return $output;
        else
            echo $output;
    }
}

$documentMap  = $modx->documentMap;

function buildStack(&$stack = array(), $level = 0)
{
  global $modx;
  
  if(empty($stack)) {
    foreach($modx->getChildIds($level, 1) as $alias => $docId)
    {
      $stack[$level][$docId] = array('id' => $docId, 'parent' => 0, 'alias' => $alias, 'level' => $level);
    }
    $level = $level + 1;
  }

  $tmp = array();
  foreach($stack[$level - 1] as $doc => $alias) {
    foreach($modx->getChildIds($doc, 1) as $alias => $docId) {
      $stack[$level][$docId] = array('id' => $docId, 'parent' => $doc, 'alias' => $alias, 'level' => $level);
    }
  }
  
  if( ! empty($stack[$level]) ) {
    buildStack($stack, $level + 1);
  }
}
$stack = array();
buildStack($stack);

$levels = count($stack);
while($levels > 1){
  $element = array_pop($stack);
  foreach($element as $doc => $attr)
  {
    $parent = $attr['parent'];
    $pLevel = $attr['level'] - 1;
  
    $stack[$pLevel][$parent]['__children'][$attr['id']] = $attr;
  }
  $levels--;
}

$stack = $stack[0];

function generateMenu($array)
{
  echo '<ul>';
  foreach($array as $doc)
  {
    echo '<li>'.$doc['alias'].'</li>';
    if( isset($doc['__children']) && ! empty($doc['__children']) )
    {
      generateMenu($doc['__children']);
    }
  }
  echo '</ul>';
}

generateMenu($stack);


$lookup = $stack;
$output = pPrint($lookup, TRUE);
$output = str_replace(array("Array", '(', ')'), '', $output);
echo $output = str_replace("\n\n", "\n", $output);