<?php

function XML_Template_process_file($filename, $obj, $clean = 1)
{
	$doc = new DOMDocument;
	$doc->load($filename);
	XML_Template_process($doc, $obj, $clean);
	return $doc;
}

function XML_Template_process($node, $obj, $clean = 1)
{
	if (is_a($obj, 'DOMNode')) {                          # overwrite
		while ($node->childNodes->length > 0) {
			$child = $node->childNodes->item(0);
			$node->removeChild($child);
		}

		if (is_a($obj, 'DOMDocument')) {
			$obj = $obj->documentElement;
		}

		$frag = $node->ownerDocument->createDocumentFragment();
		$frag->appendChild($node->ownerDocument->importNode($obj, true));
		XML_Template_process($frag, array(), $clean);
		$node->appendChild($frag);
	} else if (!is_array($obj)) {                         # overwrite
		while ($node->childNodes->length > 0) {
			$node->removeChild($node->firstChild);
		}
		$doc = $node->ownerDocument;
		$node->appendChild($doc->createTextNode($obj));
	} else if (is_associative_array($obj)) {              # substitute
		$num_children = ($node->childNodes == null) ? 0 : $node->childNodes->length;
		$children = array();
		for ($i = 0; $i < $num_children; ++$i) {
			$children[] = $node->childNodes->item($i);
		}

		for ($i = 0; $i < $num_children; ++$i) {
			$child = $children[$i];
			$processed = false;

			if ($child->nodeType == XML_ELEMENT_NODE) {
				unset($id);

				$tag = $child->localName;
				$attrs = $child->attributes;

				if (isset($attrs)) {
					$replace_child = 0;
					$id_node = $child->getAttributeNodeNS('http://template.sesse.net/', 'id');
					if (isset($id_node)) {
						$id = $id_node->value;
						if ($clean) {
							$child->removeAttributeNode($id_node);
							$replace_child = 1;
						}       
					}

					# This seems to be the only way to reliably get rid of the excess
					# XML namespace declarations.
					if ($replace_child == 1) {
						$newchild = own_clone_element($child, $child->ownerDocument);
						while ($child->childNodes->length > 0) {
							$newchild->appendChild($child->firstChild);
						}
						$node->replaceChild($newchild, $child);
						$child = $newchild;
					}
				}
			
				# check all substitutions to see if we found anything
				# appropriate
				foreach (array_keys($obj) as $key) {
					# FIXME: we would want something like \Q and \E here...
					if (preg_match('/^' . $tag . '\/(.*)$/', $key, $matches) ||
					    (isset($id) && preg_match('/^#' . $id . '\/(.*)$/', $key, $matches))) {
					    	$child->setAttribute($matches[1], $obj[$key]);
					}

					if ($processed) {
						continue;
					}
					if ($key == $tag || (isset($id) && $key == ('#'.$id))) {
						XML_Template_process($child, $obj[$key], $clean);
						$processed = true;
					}
				}
			}

			if (!$processed) {
				XML_Template_process($child, $obj, $clean);
			}
		}
	} else {						# repeat
		$doc = $node->ownerDocument;
		$frag = $doc->createDocumentFragment();

		while ($node->childNodes->length > 0) {
			$child = $node->childNodes->item(0);
			$node->removeChild($child);
			$frag->appendChild($child);
		}

		foreach ($obj as $instance) {
			if (!isset($instance)) {
				continue;
			}

			$newnode = own_clone_node($frag, $frag->ownerDocument);
			XML_Template_process($newnode, $instance, $clean);

			$node->appendChild($newnode);
			if ($clean) {
				XML_Template_clean($newnode);
			}
		}
	}

	if ($clean) {
		XML_Template_clean($node);
	}
}

function XML_Template_clean($node)
{
	if ($node->nodeType == XML_ELEMENT_NODE) {
		if ($node->namespaceURI != 'http://template.sesse.net/') {
			return;
		}

		# as this is a dummy node, we want to remove it and move everything further up
		# after we've done any required replacements
		$doc = $node->ownerDocument;
		$parent = $node->parentNode;

		while ($node->childNodes->length > 0) {
			$child = $node->childNodes->item(0);
			$node->removeChild($child);
			$parent->insertBefore(own_clone_node($child, $doc), $node);
		}
		$parent->removeChild($node);
	}
}

# FIXME: use varargs here
function XML_Template_alternate($tag, $array, $elems)
{
	$num = count($elems);

	for ($i = 0, $j = 0; $i < count($array); $i++) {
		if (isset($array[$i])) {
			$array[$i][$tag] = $elems[$j++ % $num];
		}
	}

	return $array;
}
		
# Ideally, this would be "return $obj->clone_node(true)". But surprise,
# surprise, PHP is buggy; it does not preserve the prefix information on
# attributes properly during a clone. (PHP4 and PHP5 are broken in different
# ways here...) IOW, we'll have to clone everything ourselves.
function own_clone_node($node, $doc)
{
	// we only need these two
	if ($node->nodeType == XML_DOCUMENT_FRAG_NODE) {
		$newnode = $doc->createDocumentFragment();

		for ($i = 0; $i < $node->childNodes->length; ++$i) {
			$child = $node->childNodes->item($i);
			$newnode->appendChild(own_clone_node($child, $doc));
		}
		return $newnode;
	} else if ($node->nodeType == XML_ELEMENT_NODE) {
		$newnode = own_clone_element($node, $doc);
		for ($i = 0; $i < $node->childNodes->length; ++$i) {
			$child = $node->childNodes->item($i);
			$newnode->appendChild(own_clone_node($child, $doc));
		}
		return $newnode;
	} else {
		return $node->cloneNode(true);
	}
}
		
function own_clone_element($node, $doc)
{
	$nsuri = $node->namespaceURI;
	if (isset($nsuri) && $node->prefix != "default") {
		$newnode = $doc->createElementNS($node->namespaceURI, $node->nodeName, $node->prefix);
	
		// remove useless empty text child
		$newnode->removeChild($newnode->firstChild);
	} else {
		$newnode = $doc->createElement($node->localName);
	}
	
	$attrs = $node->attributes;
	if (isset($attrs)) {
		foreach ($node->attributes as $attr) {
			$nsuri = $attr->namespaceURI;
			if (isset($nsuri) && $attr->prefix != "default") {
				$attr2 = $doc->createAttributeNS($nsuri, $attr->prefix . ":" . $attr->name);
			} else {
				$attr2 = $doc->createAttribute($attr->localName);
			}

			# You've got to be kidding me...
			$attr2->value = preg_replace("/&/", "&amp;", $attr->value);
			$newnode->appendChild($attr2);
		}
	}
	return $newnode;
}

function is_associative_array($arr)
{
	if (!is_array($arr)) {
		return false;
	}
	$diff = array_diff(range(0, count($arr) - 1), array_keys($arr));
	return (count($diff) > 0);
}
?>