var formOrder;
function init() {
    formOrder = document.forms['formOrder'].elements;
}

function arrival_check() {
    if(formOrder.dont_know_arrival.checked) {
        formOrder.date_arrival.disabled = true;
        formOrder.month_arrival.disabled = true;
        formOrder.year_arrival.disabled = true;
    }
    else {
        formOrder.date_arrival.disabled = false;
        formOrder.month_arrival.disabled = false;
        formOrder.year_arrival.disabled = false;
    }
}

function departure_check() {
    if(formOrder.dont_know_departure.checked) {
        formOrder.date_departure.disabled = true;
        formOrder.month_departure.disabled = true;
        formOrder.year_departure.disabled = true;
    }
    else {
        formOrder.date_departure.disabled = false;
        formOrder.month_departure.disabled = false;
        formOrder.year_departure.disabled = false;
    }
}


function validate_email(mailField) {
    var sEmail= new Object;
    sEmail= mailField.value;
    if (sEmail=="") {
        alert("You have not entered an email address. \n Please enter it now.")
        mailField.focus();
        mailField.select();
        return false;
    }
    if (sEmail.length > 0) {
        // Return false if e-mail field does not contain a '@' and '.'
        var atPos = sEmail.indexOf('@', 0);
        if ( (atPos == -1) || (sEmail.indexOf('@',atPos+1) > 0) || (sEmail.indexOf ('.',0) == -1) || (sEmail.indexOf('@.',0) > 0) || (sEmail.indexOf('.@', 0) > 0) || (sEmail.indexOf('.',0) == sEmail.length-1) ) {
            alert("You have entered an invalid email address. \n Please enter a correct email address now.")
            mailField.focus();
            mailField.select();
            return false;
        }
    }
    return true;
}