var bustcachevar = 1 //bust potential caching of external pages after initial request? (1=yes, 0=no)
var loadstatustext = "<img src='/images/loading.gif' /> Đang tải dữ liệu"

var loadedobjects = ""
var defaultcontentarray = new Object()
var bustcacheparameter = ""

function ajaxpage(url, containerid, targetobj) {
    var page_request = false
    if (window.XMLHttpRequest) // if Mozilla, Safari etc
    {
        page_request = new XMLHttpRequest()
    }
    else if (window.ActiveXObject) { // if IE
        try {
            page_request = new ActiveXObject("Msxml2.XMLHTTP")
        }
        catch (e) {
            try {
                page_request = new ActiveXObject("Microsoft.XMLHTTP")
            }
            catch (e) { }
        }
    }
    else
        return false
    
    var ullist = targetobj.parentNode.parentNode.getElementsByTagName("li")
    for (var i = 0; i < ullist.length; i++)
        ullist[i].className = ""  //deselect all tabs
    targetobj.parentNode.className = "selected"  //highlight currently clicked on tab
    if (url.indexOf("#default") != -1) { //if simply show default content within container (verus fetch it via ajax)
        document.getElementById(containerid).innerHTML = defaultcontentarray[containerid]
        return
    }   
    document.getElementById(containerid).innerHTML = loadstatustext
    page_request.onreadystatechange = function() {
        loadpage(page_request, containerid)
    }
    if (bustcachevar) //if bust caching of external page
        bustcacheparameter = (url.indexOf("?") != -1) ? "&" + new Date().getTime() : "?" + new Date().getTime()
    page_request.open('GET', url + bustcacheparameter, true)
    page_request.send(null)
}

function loadpage(page_request, containerid) {
    if (page_request.readyState == 4 && (page_request.status == 200 || window.location.href.indexOf("http") == -1)) {
        
        document.getElementById(containerid).innerHTML = page_request.responseText
    }
}

function loadobjs(revattribute) {
    if (revattribute != null && revattribute != "") { //if "rev" attribute is defined (load external .js or .css files)
        var objectlist = revattribute.split(/\s*,\s*/) //split the files and store as array
        for (var i = 0; i < objectlist.length; i++) {
            var file = objectlist[i]
            var fileref = ""
            if (loadedobjects.indexOf(file) == -1) { //Check to see if this object has not already been added to page before proceeding
                if (file.indexOf(".js") != -1) { //If object is a js file
                    fileref = document.createElement('script')
                    fileref.setAttribute("type", "text/javascript");
                    fileref.setAttribute("src", file);
                }
                else if (file.indexOf(".css") != -1) { //If object is a css file
                    fileref = document.createElement("link")
                    fileref.setAttribute("rel", "stylesheet");
                    fileref.setAttribute("type", "text/css");
                    fileref.setAttribute("href", file);
                }
            }
            if (fileref != "") {
                document.getElementsByTagName("head").item(0).appendChild(fileref)
                loadedobjects += file + " " //Remember this object as being already added to page
            }
        }
    }
}

function expandtab(tabcontentid, tabnumber) { //interface for selecting a tab (plus expand corresponding content)
    var thetab = document.getElementById(tabcontentid).getElementsByTagName("a")[tabnumber]
    if (thetab.getAttribute("rel")) {
        ajaxpage(thetab.getAttribute("href"), thetab.getAttribute("rel"), thetab)
        loadobjs(thetab.getAttribute("rev"))
    }
}

function savedefaultcontent(contentid) {// save default ajax tab content
    if (typeof defaultcontentarray[contentid] == "undefined") //if default content hasn't already been saved
        defaultcontentarray[contentid] = document.getElementById(contentid).innerHTML
}

function startajaxtabs() {
    for (var i = 0; i < arguments.length; i++) { //loop through passed UL ids
        var ulobj = document.getElementById(arguments[i])
        var ulist = ulobj.getElementsByTagName("li") //array containing the LI elements within UL
        for (var x = 0; x < ulist.length; x++) { //loop through each LI element
            var ulistlink = ulist[x].getElementsByTagName("a")[0]
            if (ulistlink.getAttribute("rel")) {
                //var modifiedurl = ulistlink.getAttribute("href").replace(/^http:\/\/[^\/]+\//i, "http://" + window.location.hostname + "/")
                //ulistlink.setAttribute("href", modifiedurl) //replace URL's root domain with dynamic root domain, for ajax security sake
                savedefaultcontent(ulistlink.getAttribute("rel")) //save default ajax tab content
                ulistlink.onclick = function() {
                    ajaxpage(this.getAttribute("href"), this.getAttribute("rel"), this)
                    loadobjs(this.getAttribute("rev"))
                    return false
                }
                if (ulist[x].className == "selected") {
                    ajaxpage(ulistlink.getAttribute("href"), ulistlink.getAttribute("rel"), ulistlink) //auto load currenly selected tab content
                    loadobjs(ulistlink.getAttribute("rev")) //auto load any accompanying .js and .css files
                }
            }
        }
    }
}