ForNick.php

<?php

setup();

$t = new Tree('top', 'T');
$t->append(new TreeNode('one', 1));
$t->append($x = new TreeNode('two', 2));
$t->append(new TreeNode('three', 3));
$t->append(new TreeNode('foo', 'foo'));

$x->append(new TreeNode('a', 'a'));
$x->append(new TreeNode('b', 'b'));

    //$r = new RecursiveIteratorIterator($t, RecursiveIteratorIterator::CHILD_FIRST);
    //
    //foreach ($r as $s) {
    //    
    //    
    //}

$renderer = new TreeRendererXML($t);
$renderer->render();



function setup() {
    
    
    abstract class TreeContainer implements RecursiveIterator, Countable
    {
        protected $_name = '';
        protected $_branches = array();

        public function __construct($name, $value = null)
        {
            $this->setName($name);
            if ($value) {
                $this->setValue($value);
            }
        }

        public function setName($name)
        {
            $this->_name = $name;
        }
        
        public function getName()
        {
            return $this->_name;
        }
        
        public function getValue()
        {
            return $this->_value;
        }

        public function setValue($value)
        {
            $this->_value = $value;
        }
        
        public function append(TreeContainer $node)
        {
            array_push($this->_branches, $node);
        }

        public function current()
        {
            return current($this->_branches);
        }

        public function key()
        {
            return key($this->_branches);
        }

        public function next()
        {
            return next($this->_branches);
        }

        public function rewind()
        {
            return reset($this->_branches);
        }

        public function valid()
        {
            return (bool) $this->current();
        }

        public function hasChildren()
        {
            return (count($this->_branches > 0)) ? true : false;

        }

        public function getChildren()
        {
            return $this->current();
        }

        public function count()
        {
            return count($this->_branches);
        }
        
        public function __toString()
        {
            return $this->_name;
        }
           
    }

    
    class Tree extends TreeContainer
    {
        public function setValue($value)
        {
            if ($value == 'foo') {
                $this->_value = 'BIG FUCKING FOO';
            } else {
                parent::setValue($value);
            }
        }
    }

    class TreeNode extends TreeContainer
    {

    }

    
    interface Renderer
    {
        public function render();
    }
    
    class TreeRendererHtml implements Renderer
    {
        protected $_node = null;
        
        public function __construct(TreeContainer $treeNode)
        {
            $this->_node = $treeNode;
        }
        
        public function render()
        {
            $rii = new RecursiveIteratorIterator($this->_node, RecursiveIteratorIterator::SELF_FIRST);
            
            foreach ($rii as $i) {
                echo str_repeat('    ', $rii->getDepth());
                echo $i->getName() . PHP_EOL;
            }
        }
        
    }
    
    class TreeRendererXML extends TreeRendererHtml
    {
        public function render()
        {
            $rii = new RecursiveIteratorIterator($this->_node, RecursiveIteratorIterator::SELF_FIRST);
            
            $xmlWriter = new XMLWriter();
            $xmlWriter->openURI('php://stdout');
            $xmlWriter->setIndent(true);
            $xmlWriter->setIndentString('   ');
            $xmlWriter->startDocument('1.0');
            
            $lastDepth = 0;
            
            foreach ($rii as $i) {
                
                
                if ($i->getValue()) {
                    $xmlWriter->writeElement($i->getName(), $i->getValue());
                }
                
                if ($rii->getDepth() >= $lastDepth) {
                    $xmlWriter->startElement($i->getName());
                } elseif ($rii->getDepth() < $lastDeth) {
                    $xmlWRtier->endElement();
                }
                
                
                $lastDepth = $rii->getDepth();
            }
            
            $xmlWriter->endElement();
            $xmlWriter->endDocument();
            $xmlWriter->flush();
        }
    }

    
}