/*****************************************
 * VALIDATION FUNCTION
 * Arguments:
 * str requirements: a string listing the names of all required form fields
 * str form: a string of the form id
*****************************************/
function validate(requirements, form, error_message) {
	var submitform = true;
	if (!error_message) {
		error_message = 'There are errors with your information.  Please submit all required fields.';
	}

	for (var i=0; i < document.getElementById(form).elements.length; i++) { // iterate over all form fields
		if (requirements.match(document.getElementById(form).elements[i].name)) { // if the current field is in the required string, check it
			if (!document.getElementById(form).elements[i].value) { // there is nothing in that field, so show errors, and do not submit form
				if (document.getElementById(document.getElementById(form).elements[i].name + '_error')) { // check if there's an error message to display
					document.getElementById(document.getElementById(form).elements[i].name + '_error').style.visibility = 'visible';
				}
				submitform = false;
			} // closes if empty
		} // closes if required
	} // closes for loop
	
	if (submitform) {
		document.getElementById(form).submit();
	} else {
		alert (error_message);
		return false;
	}
}

function validate_email(field_name, error_message) {
	if (!error_message) {	error_message = 'Please enter a valid email address.';	} // set default error message
	
	email_address = document.getElementsByName(field_name)[0].value; // get the submitted email address

	if (email_address.indexOf('@') && email_address.indexOf('.')) { // check to see if it has both an @ and a .
		if (email_address.indexOf('@') < email_address.indexOf('.')) { // check that the @ is before the .
			return true;
		} else {
			alert(error_message);
			return false;
		}
	}
}