// setStyleByClass: given an element type and a class selector,
// style property and value, apply the style.
// args:
//  t - type of tag to check for (e.g., SPAN)
//  c - class name
//  p - CSS property
//  v - value
var ie = (document.all) ? true : false;

function setStyleByClass(t,c,p,v){
	var elements;
	if(t == '*') {
		// '*' not supported by IE/Win 5.5 and below
		elements = (ie) ? document.all : document.getElementsByTagName('*');
	} else {
		elements = document.getElementsByTagName(t);
	}
	for(var i = 0; i < elements.length; i++){
		var node = elements.item(i);
		for(var j = 0; j < node.attributes.length; j++) {
			if(node.attributes.item(j).nodeName == 'class') {
				if(node.attributes.item(j).nodeValue == c) {
					eval('node.style.' + p + " = '" +v + "'");
				}
			}
		}
	}
}

// getStyleByClass: given an element type, a class selector and a property,
// return the value of the property for that element type.
// args:
//  t - element type
//  c - class identifier
//  p - CSS property
function getStyleByClass(t, c, p) {
	// first loop over elements, because if they've been modified they
	// will contain style data more recent than that in the stylesheet
	var elements;
	if(t == '*') {
		// '*' not supported by IE/Win 5.5 and below
		elements = (ie) ? document.all : document.getElementsByTagName('*');
	} else {
		elements = document.getElementsByTagName(t);
	}
	for(var i = 0; i < elements.length; i++){
		var node = elements.item(i);
		for(var j = 0; j < node.attributes.length; j++) {
			if(node.attributes.item(j).nodeName == 'class') {
				if(node.attributes.item(j).nodeValue == c) {
					var theStyle = eval('node.style');
					return theStyle;
					//var theStyle = eval('node.style.' + p);
					//alert("searching: "+p);
					//if((theStyle != "") && (theStyle != null)) {
					//	return theStyle;
					//}
				}
			}
		}		
	}
	// if we got here it's because we didn't find anything
	// try styleSheets
	var sheets = document.styleSheets;
	if(sheets.length > 0) {
		// loop over each sheet
		for(var x = 0; x < sheets.length; x++) {
			// grab stylesheet rules
			var rules = sheets[x].cssRules;
			if(rules.length > 0) {
				// check each rule
				for(var y = 0; y < rules.length; y++) {
					var z = rules[y].style;
					// selectorText broken in NS 6/Mozilla: see
					// http://bugzilla.mozilla.org/show_bug.cgi?id=51944
					ugly_selectorText_workaround();
					if(allStyleRules) {
						if((allStyleRules[y] == c) ||
						   (allStyleRules[y] == (t + "." + c))) {
							return z[p];
						}			
					} else {
						// use the native selectorText and style stuff
						if(((z[p] != "") && (z[p] != null)) &&
						   ((rules[y].selectorText == c) ||
						    (rules[y].selectorText == (t + "." + c)))) {
							return z[p];
						}
					}
				}
			}
		}
	}

	return null;
}

function permute() {
	var r0 = Math.round(Math.random()*3);
	var r1 = (r0 + 1)%4;
	var r2 = (r0 + 2)%4;
	var r3 = (r0 + 3)%4;
	var colors = new Array("#FF0000", "#FFC000", "#0000FF", "#000080");
	setStyleByClass("td", "red", "backgroundColor", colors[r0]);
	setStyleByClass("td", "yellow", "backgroundColor", colors[r1]);
	setStyleByClass("td", "blue", "backgroundColor", colors[r2]);
	setStyleByClass("td", "darkblue", "backgroundColor", colors[r3]);
 }