/*
    Function for swapping out DOM elements with HTML stored in external XML files
*/
function DOMSwap(xmlFilename, idToReplace) {
    if (xmlFilename != null && idToReplace != null) {
        window.addEvent('domready', function() {
            domReadyCallback(xmlFilename, idToReplace);
        });
    }
}

function domReadyCallback(xmlFilename, idToReplace) {
    var elem = document.getElementById(idToReplace);
    if (elem != null) {
        // Load text ISI XML
        var request = new XHR({
            method: "get",
            onSuccess: function(responseText, responseXml) {
                // Transfer the XML DOM to the insertion point
                var html = get_html_dom(responseXml);
                
                // Insert document nodes
                if (html != null) {
                    for (i=0; i<html.childNodes.length; i++)
                        elem.parentNode.insertBefore(html.childNodes[i], elem);
                }
                
                // Remove image
                elem.parentNode.removeChild(elem);
            }
        }).send(xmlFilename + "?random=" + Math.random());
    }
}

/*
    Converts an XML DOM to an HTML DOM
*/
function get_html_dom(xmlDOM)
{
    if (xmlDOM == null)
        return null;
    
    // Create document fragment node
    var doc = document.createDocumentFragment();
    
    // Recurse through XML tree and append to the HTML document
    get_html_dom_core(xmlDOM.documentElement, doc);
    
    // Return
    return doc;
}

/*
    Recursive core for get_html_dom
*/
function get_html_dom_core(srcXMLNode, dstHTMLNode)
{
    if (srcXMLNode == null || dstHTMLNode == null)
        return;
    
    switch (srcXMLNode.nodeType) {
        case 1: //ELEMENT_NODE
            var elem = document.createElement(srcXMLNode.nodeName);
            var i;
            
            // Get attributes
            for (i=0; i<srcXMLNode.attributes.length; i++)
                get_html_dom_core(srcXMLNode.attributes[i], elem);
            
            // Recurse through child elements
            for (i=0; i<srcXMLNode.childNodes.length; i++)
                get_html_dom_core(srcXMLNode.childNodes[i], elem);
            
            // If this is a link, make it a popup
            if (elem.tagName.toLowerCase() == "a") {
                var func = function (e) {
                    e = e || event; 
                    e.preventDefault ? e.preventDefault() : e.returnValue = false; 
                    
                    window.open(e.srcElement ? e.srcElement.href : e.target.href);
                };
                
                if (elem.addEventListener)
                    elem.addEventListener("click", func, false);
                else if (elem.attachEvent)
                    elem.attachEvent("onclick", func);
                else
                    elem.onclick = func;
            }
            
            // Add to parent
            dstHTMLNode.appendChild(elem);
            break;
            
        case 2: //ATTRIBUTE_NODE
            dstHTMLNode.setAttribute(srcXMLNode.nodeName, srcXMLNode.nodeValue);
            if (srcXMLNode.nodeName == "class")
                dstHTMLNode.setAttribute("className", srcXMLNode.nodeValue);
            break;
            
        case 3: //TEXT_NODE
            // Add to parent
            dstHTMLNode.appendChild(document.createTextNode(srcXMLNode.nodeValue));
            break;
            
        case 9: //DOCUMENT_NODE
            insertHTML(srcXMLNode.documentElement, dstHTMLNode);
            break;
    };
}