function validateForm(whichform) {
	for (var i=0; i<whichform.elements.length; i++) {
		var element = whichform.elements[i];
		if (element.className.indexOf("required") != -1) {
			if(!isFilled(element)) {
				alert("Please fill in the "+element.name+" field.");
				return false;
			}
		}
		
		if (element.className.indexOf("email") != -1) {
			if(!isEmail(element)) {
				alert("Please enter a valid email address.");
				return false;
			}
		} 
		if (element.className.indexOf("confirm") != -1) {
			if(!confirmEmail(element)) {
				alert("Please make sure email addresses match.");
				return false;
			}
		}		
	}
	
	return true;
}

function isFilled(field) {
	if (field.value == '') {
		return false;
	}
	
	return true;
}

function isEmail(field) {
	if (field.value.indexOf("@") == -1 || field.value.indexOf(".") == -1) {
		return false;
	}
	
	return true;
}  

function confirmEmail() {
	if (document.getElementById('confirm_email').value != document.getElementById('email').value) {
		return false;
	}
	
	return true;
}

function prepareForms() {
  for (var i=0; i<document.forms.length; i++) {
    var thisform = document.forms[i];
    thisform.onsubmit = function() {
      return validateForm(this);
    }
  }
}

addLoadEvent(prepareForms);