function isValidEmail(email, required) {
    if (required==undefined) {   // if not specified, assume it's required
        required=true;
    }
    if (email==null) {
        if (required) {
            return false;
        }
        return true;
    }
    if (email.length==0) {  
        if (required) {
            return false;
        }
        return true;
    }
    if (! allValidChars(email)) {  // check to make sure all characters are valid
        return false;
    }
    if (email.indexOf("@") < 1) { //  must contain @, and it must not be the first character
        return false;
    } else if (email.lastIndexOf(".") <= email.indexOf("@")) {  // last dot must be after the @
        return false;
    } else if (email.indexOf("@") == email.length) {  // @ must not be the last character
        return false;
    }
	
    return true;
}

function allValidChars(email) {
  var parsed = true;
  var validchars = "abcdefghijklmnopqrstuvwxyz0123456789@.-_";
  for (var i=0; i < email.length; i++) {
    var letter = email.charAt(i).toLowerCase();
    if (validchars.indexOf(letter) != -1)
      continue;
    parsed = false;
    break;
  }
  return parsed;
}

function valcontact() {
	if (document.contactform.name.value == '' || document.contactform.email.value == '') {
		alert("Please fill in your name and email address");
		return false;
	}else{
		if (! isValidEmail(document.contactform.email.value)) {
        	alert("Please enter a valid email address");
        	return false;
    	}else{
			return true;
		}
	}
}

function popup(thepage,thewidth,theheight) {
	window.open(thepage, "popup", "width="+thewidth+",height="+theheight+",toolbars=no,scrollbars=yes")
}

function switchProd(prodnum) {
	//turn off other link rollover styles and other image divs
	document.getElementById("prodPic").style.display = "none";
	for (i=1;i<=6;i++) {
		if (i != prodnum) {
			document.getElementById("prodPic"+i).style.display = "none";
			document.getElementById("prodlink"+i).className = "";
		}
	}
	
	//show pic & link div
	document.getElementById("prodPic"+prodnum).style.display = "block";
	//keep rollover style
	document.getElementById("prodlink"+prodnum).className = "hoverLink";
}