function show_right_nav(id) {
    if (document.getElementById) {
        for (i = 1; i <= 4; i ++) {
            if (document.getElementById("right-nav-" + i)) document.getElementById("right-nav-" + i).style.display = "";
        }
        if(document.getElementById("right-nav-" + id)){document.getElementById("right-nav-" + id).style.display = "block";}
    }
}

function show_promo(max_id) {
    if(document.promo.src){
         document.promo.src = "/images/config/promo" + (Math.round(Math.random() * (max_id - 1)) + 1) + ".jpg";
     }
}

function rate_car(id, score) {
    alert("You rated the car (ID: " + id + ") a score of " + score + " stars.");
}

function storyPhoto(imageID, largeImage) {
    document.images["story_photo_large"].src = largeImage;
    for (i = 1; i <= 3; i ++) {
        document.getElementById("story_photo_small" + i).className = "thumbnail";
    }
    document.getElementById("story_photo_small" + imageID).className = "thumbnail-on";
}

        function validateForm(formArg) {
            var firstBlankField = "";
            var blankFieldNames = new Array();
            for (i = 0; i < fields.length; i ++) {
                if ((formArg.elements[fields[i]].value == "") || (formArg.elements[fields[i]].value == "unselected")) {
                    blankFieldNames.push(fieldNames[i]);
                    if (firstBlankField == "") {
                        firstBlankField = fields[i];
                    }
                }
            }
            if (blankFieldNames.length) {
                var message = "You did not fill out all the required field(s). You are missing:\n";
                for (i = 0; i < blankFieldNames.length; i ++) {
                    message += " - " + blankFieldNames[i] + "\n";
                }
                alert(message);
                formArg.elements[firstBlankField].focus();
            } else {
                formArg.submit();
            }
        }