function SortableTable(oTable, oSortTypes) {
	this.sortTypes = oSortTypes || [];

	this.sortColumn = null;
	this.descending = null;

	var oThis = this;
	this._headerOnclick = function (e) {
		oThis.headerOnclick(e);
	};

	if (oTable) {
		this.setTable( oTable );
		this.document = oTable.ownerDocument || oTable.document;
	}
	else {
		this.document = document;
	}


	// only IE needs this
	var win = this.document.defaultView || this.document.parentWindow;
	this._onunload = function () {
		oThis.destroy();
	};
	if (win && typeof win.attachEvent != "undefined") {
		win.attachEvent("onunload", this._onunload);
	}
}

SortableTable.gecko = navigator.product == "Gecko";
SortableTable.msie = /msie/i.test(navigator.userAgent);
// Mozilla is faster when doing the DOM manipulations on
// an orphaned element. MSIE is not
SortableTable.removeBeforeSort = SortableTable.gecko;

SortableTable.prototype.onsort = function () {};

// default sort order. true -> descending, false -> ascending
SortableTable.prototype.defaultDescending = false;

// shared between all instances. This is intentional to allow external files
// to modify the prototype
SortableTable.prototype._sortTypeInfo = {};

SortableTable.prototype.setTable = function (oTable) {
	if ( this.tHead )
		this.uninitHeader();
	this.element = oTable;
	this.setTHead( oTable.tHead );
	this.setTBody( oTable.tBodies[0] );
};

SortableTable.prototype.setTHead = function (oTHead) {
	if (this.tHead && this.tHead != oTHead )
		this.uninitHeader();
	this.tHead = oTHead;
	this.initHeader( this.sortTypes );
};

SortableTable.prototype.setTBody = function (oTBody) {
	this.tBody = oTBody;
};

SortableTable.prototype.setSortTypes = function ( oSortTypes ) {
	if ( this.tHead )
		this.uninitHeader();
	this.sortTypes = oSortTypes || [];
	if ( this.tHead )
		this.initHeader( this.sortTypes );
};

// adds arrow containers and events
// also binds sort type to the header cells so that reordering columns does
// not break the sort types
SortableTable.prototype.initHeader = function (oSortTypes) {
	if (!this.tHead) return;
	var cells = this.tHead.rows[0].cells;
	var doc = this.tHead.ownerDocument || this.tHead.document;
	this.sortTypes = oSortTypes || [];
	var l = cells.length;
	var img, c;
	for (var i = 0; i < l; i++) {
		c = cells[i];
		if (this.sortTypes[i] != null && this.sortTypes[i] != "None") {
//			img = doc.createElement("IMG");
//			img.src = "images/blank.png";
//			c.appendChild(img);
			if (this.sortTypes[i] != null)
				c._sortType = this.sortTypes[i];
			if (typeof c.addEventListener != "undefined")
				c.addEventListener("click", this._headerOnclick, false);
			else if (typeof c.attachEvent != "undefined")
				c.attachEvent("onclick", this._headerOnclick);
			else
				c.onclick = this._headerOnclick;
		}
		else
		{
			c.setAttribute( "_sortType", oSortTypes[i] );
			c._sortType = "None";
		}
	}
	this.updateHeaderArrows();
};

// remove arrows and events
SortableTable.prototype.uninitHeader = function () {
	if (!this.tHead) return;
	var cells = this.tHead.rows[0].cells;
	var l = cells.length;
	var c;
	for (var i = 0; i < l; i++) {
		c = cells[i];
		if (c._sortType != null && c._sortType != "None") {
			c.removeChild(c.lastChild);
			if (typeof c.removeEventListener != "undefined")
				c.removeEventListener("click", this._headerOnclick, false);
			else if (typeof c.detachEvent != "undefined")
				c.detachEvent("onclick", this._headerOnclick);
			c._sortType = null;
			c.removeAttribute( "_sortType" );
		}
	}
};

SortableTable.prototype.updateHeaderArrows = function () {
	if (!this.tHead) return;
	var cells = this.tHead.rows[0].cells;
	var l = cells.length;
	var img;
	for (var i = 0; i < l; i++) {
		if (cells[i]._sortType != null && cells[i]._sortType != "None") {
			img = cells[i].lastChild;
			if (i == this.sortColumn)
				img.className = "sort-arrow " + (this.descending ? "descending" : "ascending");
			else
				img.className = "sort-arrow";
		}
	}
};

SortableTable.prototype.headerOnclick = function (e) {
	// find TD element
	var el = e.target || e.srcElement;
	while (el.tagName != "TD")
		el = el.parentNode;

	this.sort(SortableTable.msie ? SortableTable.getCellIndex(el) : el.cellIndex);
};

// IE returns wrong cellIndex when columns are hidden
SortableTable.getCellIndex = function (oTd) {
	var cells = oTd.parentNode.childNodes
	var l = cells.length;
	var i;
	for (i = 0; cells[i] != oTd && i < l; i++)
		;
	return i;
};

SortableTable.prototype.getSortType = function (nColumn) {
	return this.sortTypes[nColumn] || "String";
};

// only nColumn is required
// if bDescending is left out the old value is taken into account
// if sSortType is left out the sort type is found from the sortTypes array

SortableTable.prototype.sort = function (nColumn, bDescending, sSortType) {
	if (!this.tBody) return;
	if (sSortType == null)
		sSortType = this.getSortType(nColumn);

	// exit if None
	if (sSortType == "None")
		return;

	if (bDescending == null) {
		if (this.sortColumn != nColumn)
			this.descending = this.defaultDescending;
		else
			this.descending = !this.descending;
	}
	else
		this.descending = bDescending;

	this.sortColumn = nColumn;

	if (typeof this.onbeforesort == "function")
		this.onbeforesort();

	var f = this.getSortFunction(sSortType, nColumn);
	var a = this.getCache(sSortType, nColumn);
	var tBody = this.tBody;

	a.sort(f);
	//alert(a[0].element.cells[0].innerHTML);
	if (this.descending)
		a.reverse();

	if (SortableTable.removeBeforeSort) {
		// remove from doc
		var nextSibling = tBody.nextSibling;
		var p = tBody.parentNode;
		p.removeChild(tBody);
	}
	

	// insert in the new order
	var l = a.length;
	
	
	for (var i = 0; i < l; i++){
		var cn = a[i].element.cells[0].childNodes;
		var ch = false;
		if(cn[0].checked==true){
			ch=true;
		}
		tBody.appendChild(a[i].element);
		if(ch==true){
			var cn1 = tBody.rows[(l-1)].cells[0].childNodes;
			cn1[0].checked=ch;
		}
	}

	if (SortableTable.removeBeforeSort) {
		// insert into doc
		p.insertBefore(tBody, nextSibling);
	}

	this.updateHeaderArrows();

	this.destroyCache(a);

	if (typeof this.onsort == "function")
		this.onsort();
};

SortableTable.prototype.asyncSort = function (nColumn, bDescending, sSortType) {
	var oThis = this;
	this._asyncsort = function () {
		oThis.sort(nColumn, bDescending, sSortType);
	};
	window.setTimeout(this._asyncsort, 1);
};

SortableTable.prototype.getCache = function (sType, nColumn) {
	if (!this.tBody) return [];
	var rows = this.tBody.rows;
	var l = rows.length;
	var a = new Array(l);
	var r;
	for (var i = 0; i < l; i++) {
		r = rows[i];
		a[i] = {
			value:		this.getRowValue(r, sType, nColumn),
			element:	r
		};
	};
	return a;
};

SortableTable.prototype.destroyCache = function (oArray) {
	var l = oArray.length;
	for (var i = 0; i < l; i++) {
		oArray[i].value = null;
		oArray[i].element = null;
		oArray[i] = null;
	}
};

SortableTable.prototype.getRowValue = function (oRow, sType, nColumn) {
	// if we have defined a custom getRowValue use that

	if (this._sortTypeInfo[sType] && this._sortTypeInfo[sType].getRowValue)
	{
		return this._sortTypeInfo[sType].getRowValue(oRow, nColumn);
	}
		

	var s;
	var c = oRow.cells[nColumn];
	if (typeof c.innerText != "undefined"){
		s = c.innerText;
	}else{
		s = SortableTable.getInnerText(c);
	}
	return this.getValueFromString(s, sType);
};

SortableTable.getInnerText = function (oNode) {
	var s = "";
	var cs = oNode.childNodes;
	var l = cs.length;
	for (var i = 0; i < l; i++) {
		switch (cs[i].nodeType) {
			case 1: //ELEMENT_NODE
				s += SortableTable.getInnerText(cs[i]);
				break;
			case 3:	//TEXT_NODE
				s += cs[i].nodeValue;
				break;
		}
	}
	return s;
};

SortableTable.prototype.getValueFromString = function (sText, sType) {
	if (this._sortTypeInfo[sType]){
		return this._sortTypeInfo[sType].getValueFromString( sText );
	}
	return sText;
	/*
	switch (sType) {
		case "Number":
			return Number(sText);
		case "CaseInsensitiveString":
			return sText.toUpperCase();
		case "Date":
			var parts = sText.split("-");
			var d = new Date(0);
			d.setFullYear(parts[0]);
			d.setDate(parts[2]);
			d.setMonth(parts[1] - 1);
			return d.valueOf();
	}
	return sText;
	*/
	};

SortableTable.prototype.getSortFunction = function (sType, nColumn) {
	if (this._sortTypeInfo[sType])
		return this._sortTypeInfo[sType].compare;
	return SortableTable.basicCompare;
};

SortableTable.prototype.destroy = function () {
	this.uninitHeader();
	var win = this.document.parentWindow;
	if (win && typeof win.detachEvent != "undefined") {	// only IE needs this
		win.detachEvent("onunload", this._onunload);
	}
	this._onunload = null;
	this.element = null;
	this.tHead = null;
	this.tBody = null;
	this.document = null;
	this._headerOnclick = null;
	this.sortTypes = null;
	this._asyncsort = null;
	this.onsort = null;
};

// Adds a sort type to all instance of SortableTable
// sType : String - the identifier of the sort type
// fGetValueFromString : function ( s : string ) : T - A function that takes a
//    string and casts it to a desired format. If left out the string is just
//    returned
// fCompareFunction : function ( n1 : T, n2 : T ) : Number - A normal JS sort
//    compare function. Takes two values and compares them. If left out less than,
//    <, compare is used
// fGetRowValue : function( oRow : HTMLTRElement, nColumn : int ) : T - A function
//    that takes the row and the column index and returns the value used to compare.
//    If left out then the innerText is first taken for the cell and then the
//    fGetValueFromString is used to convert that string the desired value and type

SortableTable.prototype.addSortType = function (sType, fGetValueFromString, fCompareFunction, fGetRowValue) {
	this._sortTypeInfo[sType] = {
		type:				sType,
		getValueFromString:	fGetValueFromString || SortableTable.idFunction,
		compare:			fCompareFunction || SortableTable.basicCompare,
		getRowValue:		fGetRowValue
	};
};

// this removes the sort type from all instances of SortableTable
SortableTable.prototype.removeSortType = function (sType) {
	delete this._sortTypeInfo[sType];
};

SortableTable.basicCompare = function compare(n1, n2) {
	if (n1.value < n2.value)
		return -1;
	if (n2.value < n1.value)
		return 1;
	return 0;
};

SortableTable.idFunction = function (x) {
	return x;
};

SortableTable.toUpperCase = function (s) {
	return s.toUpperCase();
};

SortableTable.toDate = function (s) {
	var parts = s.split("-");
	var d = new Date(0);
	d.setFullYear(parts[0]);
	d.setDate(parts[2]);
	d.setMonth(parts[1] - 1);
	return d.valueOf();
};


// add sort types
SortableTable.prototype.addSortType("Number", Number);
SortableTable.prototype.addSortType("CaseInsensitiveString", SortableTable.toUpperCase);
SortableTable.prototype.addSortType("Date", SortableTable.toDate);
SortableTable.prototype.addSortType("String");
// None is a special case






















/*

addEvent(window, "load", sortables_init);

var SORT_COLUMN_INDEX;

function sortables_init() {
    // Find all tables with class sortable and make them sortable
    if (!document.getElementsByTagName) return;
    tbls = document.getElementsByTagName("table");
    for (ti=0;ti<tbls.length;ti++) {
        thisTbl = tbls[ti];
        if (((' '+thisTbl.className+' ').indexOf("sortable") != -1) && (thisTbl.id)) {
            //initTable(thisTbl.id);
            ts_makeSortable(thisTbl);
        }
    }
}

function ts_makeSortable(table) {
    if (table.rows && table.rows.length > 0) {
        var firstRow = table.rows[0];
    }
    if (!firstRow) return;
    
    // We have a first row: assume it's the header, and make its contents clickable links
    for (var i=0;i<firstRow.cells.length;i++) {
        var cell = firstRow.cells[i];
        var txt = ts_getInnerText(cell);
        cell.innerHTML = '<a href="#" class="sortheader" '+ 
        'onclick="ts_resortTable(this, '+i+');return false;">' + 
        txt+'<span class="sortarrow">&nbsp;&nbsp;&nbsp;</span></a>';
    }
}

function ts_getInnerText(el) {
	if (typeof el == "string") return el;
	if (typeof el == "undefined") { return el };
	if (el.innerText) return el.innerText;	//Not needed but it is faster
	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 += ts_getInnerText(cs[i]);
				break;
			case 3:	//TEXT_NODE
				str += cs[i].nodeValue;
				break;
		}
	}
	return str;
}

function ts_resortTable(lnk,clid) {
    // get the span
    var span;
    for (var ci=0;ci<lnk.childNodes.length;ci++) {
        if (lnk.childNodes[ci].tagName && lnk.childNodes[ci].tagName.toLowerCase() == 'span') span = lnk.childNodes[ci];
    }
    var spantext = ts_getInnerText(span);
    var td = lnk.parentNode;
    var column = clid || td.cellIndex;
    var table = getParent(td,'TABLE');
    
    // Work out a type for the column
    if (table.rows.length <= 1) return;
    var itm = ts_getInnerText(table.rows[1].cells[column]);
    sortfn = ts_sort_caseinsensitive;
    if (itm.match(/^\d\d[\/-]\d\d[\/-]\d\d\d\d$/)) sortfn = ts_sort_date;
    if (itm.match(/^\d\d[\/-]\d\d[\/-]\d\d$/)) sortfn = ts_sort_date;
    if (itm.match(/^[£$]/)) sortfn = ts_sort_currency;
    if (itm.match(/^[\d\.]+$/)) sortfn = ts_sort_numeric;
    SORT_COLUMN_INDEX = column;
    var firstRow = new Array();
    var newRows = new Array();
    for (i=0;i<table.rows[0].length;i++) { firstRow[i] = table.rows[0][i]; }
    for (j=1;j<table.rows.length;j++) { newRows[j-1] = table.rows[j]; }

    newRows.sort(sortfn);

    if (span.getAttribute("sortdir") == 'down') {
        ARROW = '&nbsp;&nbsp;&uarr;';
        newRows.reverse();
        span.setAttribute('sortdir','up');
    } else {
        ARROW = '&nbsp;&nbsp;&darr;';
        span.setAttribute('sortdir','down');
    }
    
    // We appendChild rows that already exist to the tbody, so it moves them rather than creating new ones
    // don't do sortbottom rows
    for (i=0;i<newRows.length;i++) { if (!newRows[i].className || (newRows[i].className && (newRows[i].className.indexOf('sortbottom') == -1))) table.tBodies[0].appendChild(newRows[i]);}
    // do sortbottom rows only
    for (i=0;i<newRows.length;i++) { if (newRows[i].className && (newRows[i].className.indexOf('sortbottom') != -1)) table.tBodies[0].appendChild(newRows[i]);}
    
    // Delete any other arrows there may be showing
    var allspans = document.getElementsByTagName("span");
    for (var ci=0;ci<allspans.length;ci++) {
        if (allspans[ci].className == 'sortarrow') {
            if (getParent(allspans[ci],"table") == getParent(lnk,"table")) { // in the same table as us?
                allspans[ci].innerHTML = '&nbsp;&nbsp;&nbsp;';
            }
        }
    }
        
    span.innerHTML = ARROW;
}

function getParent(el, pTagName) {
	if (el == null) return null;
	else if (el.nodeType == 1 && el.tagName.toLowerCase() == pTagName.toLowerCase())	// Gecko bug, supposed to be uppercase
		return el;
	else
		return getParent(el.parentNode, pTagName);
}
function ts_sort_date(a,b) {
    // y2k notes: two digit years less than 50 are treated as 20XX, greater than 50 are treated as 19XX
    aa = ts_getInnerText(a.cells[SORT_COLUMN_INDEX]);
    bb = ts_getInnerText(b.cells[SORT_COLUMN_INDEX]);
    if (aa.length == 10) {
        dt1 = aa.substr(6,4)+aa.substr(3,2)+aa.substr(0,2);
    } else {
        yr = aa.substr(6,2);
        if (parseInt(yr) < 50) { yr = '20'+yr; } else { yr = '19'+yr; }
        dt1 = yr+aa.substr(3,2)+aa.substr(0,2);
    }
    if (bb.length == 10) {
        dt2 = bb.substr(6,4)+bb.substr(3,2)+bb.substr(0,2);
    } else {
        yr = bb.substr(6,2);
        if (parseInt(yr) < 50) { yr = '20'+yr; } else { yr = '19'+yr; }
        dt2 = yr+bb.substr(3,2)+bb.substr(0,2);
    }
    if (dt1==dt2) return 0;
    if (dt1<dt2) return -1;
    return 1;
}

function ts_sort_currency(a,b) { 
    aa = ts_getInnerText(a.cells[SORT_COLUMN_INDEX]).replace(/[^0-9.]/g,'');
    bb = ts_getInnerText(b.cells[SORT_COLUMN_INDEX]).replace(/[^0-9.]/g,'');
    return parseFloat(aa) - parseFloat(bb);
}

function ts_sort_numeric(a,b) { 
    aa = parseFloat(ts_getInnerText(a.cells[SORT_COLUMN_INDEX]));
    if (isNaN(aa)) aa = 0;
    bb = parseFloat(ts_getInnerText(b.cells[SORT_COLUMN_INDEX])); 
    if (isNaN(bb)) bb = 0;
    return aa-bb;
}

function ts_sort_caseinsensitive(a,b) {
    aa = ts_getInnerText(a.cells[SORT_COLUMN_INDEX]).toLowerCase();
    bb = ts_getInnerText(b.cells[SORT_COLUMN_INDEX]).toLowerCase();
    if (aa==bb) return 0;
    if (aa<bb) return -1;
    return 1;
}

function ts_sort_default(a,b) {
    aa = ts_getInnerText(a.cells[SORT_COLUMN_INDEX]);
    bb = ts_getInnerText(b.cells[SORT_COLUMN_INDEX]);
    if (aa==bb) return 0;
    if (aa<bb) return -1;
    return 1;
}


function addEvent(elm, evType, fn, useCapture)
// addEvent and removeEvent
// cross-browser event handling for IE5+,  NS6 and Mozilla
// By Scott Andrew
{
  if (elm.addEventListener){
    elm.addEventListener(evType, fn, useCapture);
    return true;
  } else if (elm.attachEvent){
    var r = elm.attachEvent("on"+evType, fn);
    return r;
  } else {
    alert("Handler could not be removed");
  }
} 
*/