function missingYears(){
	if(document.getElementsByTagName){
		var cells = document.getElementsByTagName("td");
		for (var i = 0; i < cells.length; i++){
			if(cells[i].innerHTML ==''){
				cells[i].parentNode.style.color='red';
				cells[i].appendChild(document.createTextNode('Fall 2222'));
				cells[i].style.fontSize='0px';
				cells[i].style.color='white';
			}
		}
	}
}

function alternate(id){
	if(document.getElementsByTagName){
		var rows = document.getElementById(id).getElementsByTagName("tr");
		for(var i = 0; i < rows.length; i++){
			if(i % 2 == 0)
				rows[i].className = "shadedRow";
			else
				rows[i].className = "nonShadedRow";
		}
	}
}


//based on code from http://www.kryogenix.org/code/browser/sorttable/

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 sortBy(columnID){
	if (document.getElementById && document.getElementById(columnID).firstChild.onclick())
		document.getElementById(columnID).firstChild.onclick();
}

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;
	if (itm.match(/^(Fall|Spring) \d\d\d\d$/)) sortfn = ts_sort_semester;
	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 that may be showing
	var allspans = document.getElementsByTagName("span");
	for (var ci2=0;ci2<allspans.length;ci2++) {
		if (allspans[ci2].className == 'sortarrow') {
			if (getParent(allspans[ci2],"table") == getParent(lnk,"table")) { // in the same table as us?
				allspans[ci2].innerHTML = '&nbsp;&nbsp;&nbsp;';
			}
		}
	}
	span.innerHTML = ARROW;
*/

   if (document.getElementById('sortedBy'))
      document.getElementById('sortedBy').id='';
	lnk.id='sortedBy';
	
  //redo row shading
	alternate(thisTbl.id);
}

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_semester(a,b) {
	aa = ts_getInnerText(a.cells[SORT_COLUMN_INDEX]);
	bb = ts_getInnerText(b.cells[SORT_COLUMN_INDEX]);
	
	aYear = parseInt(aa.match(/\d\d\d\d/));
	bYear = parseInt(bb.match(/\d\d\d\d/));
	aSem = aa.match(/Spring|Fall/);
	bSem = bb.match(/Spring|Fall/);
	
	if(aYear == bYear && aSem == bSem) return 0; //both blank or both same semester
	if(aYear == bYear && aSem == "Spring") return 1; //same year, a=spring
	if(aYear == bYear && aSem == "Fall") return -1; //same year, a=spring
	return bYear-aYear; //different years
}

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;
}