// Copyright 2005 Google Inc.
// All Rights Reserved
//
// An XML parse and a minimal DOM implementation that just supportes
// the subset of the W3C DOM that is used in the XSLT implementation.
//
// References:
//
// [DOM] W3C DOM Level 3 Core Specification
// .
//
//
// Author: Steffen Meschkat
// NOTE: The split() method in IE omits empty result strings. This is
// utterly annoying. So we don't use it here.
// Resolve entities in XML text fragments. According to the DOM
// specification, the DOM is supposed to resolve entity references at
// the API level. I.e. no entity references are passed through the
// API. See "Entities and the DOM core", p.12, DOM 2 Core
// Spec. However, different browsers actually pass very different
// values at the API.
//
function xmlResolveEntities(s) {
var parts = stringSplit(s, '&');
var ret = parts[0];
for (var i = 1; i < parts.length; ++i) {
var rp = stringSplit(parts[i], ';');
if (rp.length == 1) {
// no entity reference: just a & but no ;
ret += parts[i];
continue;
}
var ch;
switch (rp[0]) {
case 'lt':
ch = '<';
break;
case 'gt':
ch = '>';
break;
case 'amp':
ch = '&';
break;
case 'quot':
ch = '"';
break;
case 'apos':
ch = '\'';
break;
case 'nbsp':
ch = String.fromCharCode(160);
break;
default:
// Cool trick: let the DOM do the entity decoding. We assign
// the entity text through non-W3C DOM properties and read it
// through the W3C DOM. W3C DOM access is specified to resolve
// entities.
var span = window.document.createElement('span');
span.innerHTML = '&' + rp[0] + '; ';
ch = span.childNodes[0].nodeValue.charAt(0);
}
ret += ch + rp[1];
}
return ret;
}
// Parses the given XML string with our custom, JavaScript XML parser. Written
// by Steffen Meschkat (mesch@google.com).
function xmlParse(xml) {
Timer.start('xmlparse');
var regex_empty = /\/$/;
// See also for
// allowed chars in a tag and attribute name. TODO(mesch): the
// following is still not completely correct.
var regex_tagname = /^([\w:-]*)/;
var regex_attribute = /([\w:-]+)\s?=\s?('([^\']*)'|"([^\"]*)")/g;
var xmldoc = new XDocument();
var root = xmldoc;
// For the record: in Safari, we would create native DOM nodes, but
// in Opera that is not possible, because the DOM only allows HTML
// element nodes to be created, so we have to do our own DOM nodes.
// xmldoc = document.implementation.createDocument('','',null);
// root = xmldoc; // .createDocumentFragment();
// NOTE(mesch): using the DocumentFragment instead of the Document
// crashes my Safari 1.2.4 (v125.12).
var stack = [];
var parent = root;
stack.push(parent);
var x = stringSplit(xml, '<');
for (var i = 1; i < x.length; ++i) {
var xx = stringSplit(x[i], '>');
var tag = xx[0];
var text = xmlResolveEntities(xx[1] || '');
if (tag.charAt(0) == '/') {
stack.pop();
parent = stack[stack.length-1];
} else if (tag.charAt(0) == '?') {
// Ignore XML declaration and processing instructions
} else if (tag.charAt(0) == '!') {
// Ignore notation and comments
} else {
var empty = tag.match(regex_empty);
var tagname = regex_tagname.exec(tag)[1];
var node = xmldoc.createElement(tagname);
var att;
while (att = regex_attribute.exec(tag)) {
var val = xmlResolveEntities(att[3] || att[4] || '');
node.setAttribute(att[1], val);
}
if (empty) {
parent.appendChild(node);
} else {
parent.appendChild(node);
parent = node;
stack.push(node);
}
}
if (text && parent != root) {
parent.appendChild(xmldoc.createTextNode(text));
}
}
Timer.end('xmlparse');
return root;
}
// Our W3C DOM Node implementation. Note we call it XNode because we
// can't define the identifier Node. We do this mostly for Opera,
// where we can't reuse the HTML DOM for parsing our own XML, and for
// Safari, where it is too expensive to have the template processor
// operate on native DOM nodes.
function XNode(type, name, value, owner) {
this.attributes = [];
this.childNodes = [];
XNode.init.call(this, type, name, value, owner);
}
// Don't call as method, use apply() or call().
XNode.init = function(type, name, value, owner) {
this.nodeType = type - 0;
this.nodeName = '' + name;
this.nodeValue = '' + value;
this.ownerDocument = owner;
this.firstChild = null;
this.lastChild = null;
this.nextSibling = null;
this.previousSibling = null;
this.parentNode = null;
}
XNode.unused_ = [];
XNode.recycle = function(node) {
if (!node) {
return;
}
if (node.constructor == XDocument) {
XNode.recycle(node.documentElement);
return;
}
if (node.constructor != this) {
return;
}
XNode.unused_.push(node);
for (var a = 0; a < node.attributes.length; ++a) {
XNode.recycle(node.attributes[a]);
}
for (var c = 0; c < node.childNodes.length; ++c) {
XNode.recycle(node.childNodes[c]);
}
node.attributes.length = 0;
node.childNodes.length = 0;
XNode.init.call(node, 0, '', '', null);
}
XNode.create = function(type, name, value, owner) {
if (XNode.unused_.length > 0) {
var node = XNode.unused_.pop();
XNode.init.call(node, type, name, value, owner);
return node;
} else {
return new XNode(type, name, value, owner);
}
}
XNode.prototype.appendChild = function(node) {
// firstChild
if (this.childNodes.length == 0) {
this.firstChild = node;
}
// previousSibling
node.previousSibling = this.lastChild;
// nextSibling
node.nextSibling = null;
if (this.lastChild) {
this.lastChild.nextSibling = node;
}
// parentNode
node.parentNode = this;
// lastChild
this.lastChild = node;
// childNodes
this.childNodes.push(node);
}
XNode.prototype.replaceChild = function(newNode, oldNode) {
if (oldNode == newNode) {
return;
}
for (var i = 0; i < this.childNodes.length; ++i) {
if (this.childNodes[i] == oldNode) {
this.childNodes[i] = newNode;
var p = oldNode.parentNode;
oldNode.parentNode = null;
newNode.parentNode = p;
p = oldNode.previousSibling;
oldNode.previousSibling = null;
newNode.previousSibling = p;
if (newNode.previousSibling) {
newNode.previousSibling.nextSibling = newNode;
}
p = oldNode.nextSibling;
oldNode.nextSibling = null;
newNode.nextSibling = p;
if (newNode.nextSibling) {
newNode.nextSibling.previousSibling = newNode;
}
if (this.firstChild == oldNode) {
this.firstChild = newNode;
}
if (this.lastChild == oldNode) {
this.lastChild = newNode;
}
break;
}
}
}
XNode.prototype.insertBefore = function(newNode, oldNode) {
if (oldNode == newNode) {
return;
}
if (oldNode.parentNode != this) {
return;
}
if (newNode.parentNode) {
newNode.parentNode.removeChild(newNode);
}
var newChildren = [];
for (var i = 0; i < this.childNodes.length; ++i) {
var c = this.childNodes[i];
if (c == oldNode) {
newChildren.push(newNode);
newNode.parentNode = this;
newNode.previousSibling = oldNode.previousSibling;
oldNode.previousSibling = newNode;
if (newNode.previousSibling) {
newNode.previousSibling.nextSibling = newNode;
}
newNode.nextSibling = oldNode;
if (this.firstChild == oldNode) {
this.firstChild = newNode;
}
}
newChildren.push(c);
}
this.childNodes = newChildren;
}
XNode.prototype.removeChild = function(node) {
var newChildren = [];
for (var i = 0; i < this.childNodes.length; ++i) {
var c = this.childNodes[i];
if (c != node) {
newChildren.push(c);
} else {
if (c.previousSibling) {
c.previousSibling.nextSibling = c.nextSibling;
}
if (c.nextSibling) {
c.nextSibling.previousSibling = c.previousSibling;
}
if (this.firstChild == c) {
this.firstChild = c.nextSibling;
}
if (this.lastChild == c) {
this.lastChild = c.previousSibling;
}
}
}
this.childNodes = newChildren;
}
XNode.prototype.hasAttributes = function() {
return this.attributes.length > 0;
}
XNode.prototype.setAttribute = function(name, value) {
for (var i = 0; i < this.attributes.length; ++i) {
if (this.attributes[i].nodeName == name) {
this.attributes[i].nodeValue = '' + value;
return;
}
}
this.attributes.push(new XNode(DOM_ATTRIBUTE_NODE, name, value));
}
XNode.prototype.getAttribute = function(name) {
for (var i = 0; i < this.attributes.length; ++i) {
if (this.attributes[i].nodeName == name) {
return this.attributes[i].nodeValue;
}
}
return null;
}
XNode.prototype.removeAttribute = function(name) {
var a = [];
for (var i = 0; i < this.attributes.length; ++i) {
if (this.attributes[i].nodeName != name) {
a.push(this.attributes[i]);
}
}
this.attributes = a;
}
function XDocument() {
XNode.call(this, DOM_DOCUMENT_NODE, '#document', null, this);
this.documentElement = null;
}
XDocument.prototype = new XNode(DOM_DOCUMENT_NODE, '#document');
XDocument.prototype.clear = function() {
XNode.recycle(this.documentElement);
this.documentElement = null;
}
XDocument.prototype.appendChild = function(node) {
XNode.prototype.appendChild.call(this, node);
this.documentElement = this.childNodes[0];
}
XDocument.prototype.createElement = function(name) {
return XNode.create(DOM_ELEMENT_NODE, name, null, this);
}
XDocument.prototype.createDocumentFragment = function() {
return XNode.create(DOM_DOCUMENT_FRAGMENT_NODE, '#document-fragment',
null, this);
}
XDocument.prototype.createTextNode = function(value) {
return XNode.create(DOM_TEXT_NODE, '#text', value, this);
}
XDocument.prototype.createAttribute = function(name) {
return XNode.create(DOM_ATTRIBUTE_NODE, name, null, this);
}
XDocument.prototype.createComment = function(data) {
return XNode.create(DOM_COMMENT_NODE, '#comment', data, this);
}
XNode.prototype.getElementsByTagName = function(name, list) {
if (!list) {
list = [];
}
if (this.nodeName == name) {
list.push(this);
}
for (var i = 0; i < this.childNodes.length; ++i) {
this.childNodes[i].getElementsByTagName(name, list);
}
return list;
}