// tablesort.js
// Functions to perform the sorting of the table when the <thead> element is
// clicked.
// Function works with both ie and netscape DOM
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.createElement("IMG");
	tn.setAttribute('src', 'pixel.gif');
	tn.setAttribute('width','20');
	tn.setAttribute('height','10');
	arrowUp.appendChild(tn);
	arrowUp.className = "arrow_up";
	arrowDown = document.createElement("SPAN");
	var tn = document.createElement("IMG");
	tn.setAttribute('src', 'pixel.gif');
	tn.setAttribute('width','20');
	tn.setAttribute('height','10');
	arrowDown.appendChild(tn);
	arrowDown.className = "arrow_down";
}
function sortTable(tableNode, nCol, bDesc, sType) {
	var tBody = tableNode.tBodies[0];
	var trs = tBody.rows;
	var trl= trs.length;
	var a = new Array();
	
	for (var i = 0; i < trl; i++) {
		a[i] = trs[i];
	}
	
	var start = new Date;
	window.status = "Sorting data...";
	a.sort(compareByColumn(nCol,bDesc,sType));

	
	for (var i = 0; i < trl; i++) {
		tBody.appendChild(a[i]);
		window.status = "Updating row " + (i + 1) + " of " + trl +
						" (Time spent: " + (new Date - start) + "ms)";
	}
	// check for onsort
	if (typeof tableNode.onsort == "string")
		tableNode.onsort = new Function("", tableNode.onsort);
	if (typeof tableNode.onsort == "function")
		tableNode.onsort();
	window.status = "Sorting Complete.";
}
function CaseInsensitiveString(s) {
	return String(s).toUpperCase();
}
function parseDate(s) {
	var dt = Date.parse(s.replace(/\-/g, '/'));
	return new Date(dt ? dt : 0);
}
function toNumber(s) {
    var nm = Number(s.replace(/[^0-9\.]/g, ""));
    return (nm ? nm : 0);
}
function compareByColumn(nCol, bDescending, sType) {
	var c = nCol;
	var d = bDescending;
	
	var fTypeCast = CaseInsensitiveString;
	
	if (sType == "Number")
		fTypeCast = toNumber;
	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 = e.target ? e.target : e.srcElement;
	var tHeadParent = getParent(tmp, "THEAD");
	var el = getParent(tmp, "TD");
	if (tHeadParent == null)
		return;
		
	if (el != null) {
		var p = el.parentNode;
		var i;
		// typecast to Boolean
		el._descending = !Boolean(el._descending);
		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 = arrowUp.cloneNode(true);
		else
			tHeadParent.arrow = arrowDown.cloneNode(true);
		el.appendChild(tHeadParent.arrow);
			
		// get the index of the td
		var cells = p.cells;
		var l = cells.length;
		for (i = 0; i < l; i++) {
			if (cells[i] == el) break;
		}
		var table = getParent(el, "TABLE");
		// can't fail
		
		sortTable(table,i,el._descending, el.getAttribute("type"));
	}
}
function getInnerText(el) {
	if (ie5) return el.innerText;
	
	var str = "";
	
	var cs = el.childNodes;
	var l = cs.length;
	for (var i = 0; i < l; i++) {
		switch (cs[i].nodeType) {
			case 1: //ELEMENT_NODE
				str += getInnerText(cs[i]);
				break;
			case 3:	//TEXT_NODE
				str += cs[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);
}