var dom = (document.getElementsByTagName) ? true : false;
var ie5 = (document.getElementsByTagName && document.all) ? true : false;
var arrowUp, arrowDown;
if (ie5 || dom)
    initSortTable();
function initSortTable() {
    arrowUp = document.createElement("span");
    var tn = document.createTextNode("↓");
    arrowUp.appendChild(tn);
    arrowUp.className = "arrowUp";
    arrowDown = document.createElement("span");
    var tn = document.createTextNode("↑");
    arrowDown.appendChild(tn);
    arrowDown.className = "arrowDown";
}

function sortTable(tableNode, nCol, bDesc, sType) {
    var tBody = tableNode.tBodies[0];
    var trs = tBody.rows;
    var a = new Array();

    for (var i = 0; i < trs.length; i++) {
        a[i] = trs[i];
    }

    a.sort(compareByColumn(nCol, bDesc, sType));

    for (var i = 0; i < a.length; i++) {
        tBody.appendChild(a[i]);
    }
}
function CaseInsensitiveString(s) {
    return String(s).toUpperCase();
}
function parseDate(s) {
    return Date.parse(s.replace(/\-/g, '/'));
}
function toNumber(s) {
    return Number(s.replace(/[^0-9\.]/g, ""));
}
function compareByColumn(nCol, bDescending, sType) {
    var c = nCol;
    var d = bDescending;

    var fTypeCast = String;

    if (sType == "Number")
        fTypeCast = Number;
    else if (sType == "Date")
        fTypeCast = parseDate;
    else if (sType == "CaseInsensitiveString")
        fTypeCast = CaseInsensitiveString;
    return function(n1, n2) {
        if (fTypeCast(getInnerText(n1.cells[c])) < fTypeCast(getInnerText(n2.cells[c])))
            return d ? -1 : +1;
        if (fTypeCast(getInnerText(n1.cells[c])) > fTypeCast(getInnerText(n2.cells[c])))
            return d ? +1 : -1;
        return 0;
    };
}

function sortColumn(e) {
    var tmp, el, tHeadParent;
    if (ie5)
        tmp = e.srcElement;
    else if (dom)
        tmp = e.target;
    tHeadParent = getParent(tmp, "thead");
    el = getParent(tmp, "th");
    if (tHeadParent == null)
        return;

    if (el != null) {
        var p = el.parentNode;
        var i;
        if (el._descending) // catch the null
            el._descending = false;
        else
            el._descending = true;

        if (tHeadParent.arrow != null) {
            if (tHeadParent.arrow.parentNode != el) {
                tHeadParent.arrow.parentNode._descending = null;
            }
            tHeadParent.arrow.parentNode.removeChild(tHeadParent.arrow);
        }
        if (el._descending)
            tHeadParent.arrow = arrowDown.cloneNode(true);
        else
            tHeadParent.arrow = arrowUp.cloneNode(true);
        el.appendChild(tHeadParent.arrow);

        // get the index of the td
        for (i = 0; i < p.cells.length; i++) {
            if (p.cells[i] == el) break;
        }
        var table = getParent(el, "table");
        // can't fail
        //alert(el.getAttribute("type"));
        sortTable(table, i, el._descending, el.getAttribute("type"));
    }
}

function getInnerText(el) {
    if (ie5) return el.innerText; //Not needed but it is faster

    var str = "";

    for (var i = 0; i < el.childNodes.length; i++) {
        switch (el.childNodes.item(i).nodeType) {
            case 1: //ELEMENT_NODE
                str += getInnerText(el.childNodes.item(i));
                break;
            case 3: //TEXT_NODE
                str += el.childNodes.item(i).nodeValue;
                break;
        }

    }

    return str;
}
function getParent(el, pTagName) {
    if (el == null) return null;
    else if (el.nodeType == 1 && el.tagName.toLowerCase() == pTagName.toLowerCase())
        return el;
    else
        return getParent(el.parentNode, pTagName);
}