// *** rollovers
function init() {
    var items = document.getElementById("navigation").getElementsByTagName("li");
    for (var i = 0; i < items.length; i++) {
        var item = items[i];
        var url = item.getElementsByTagName("a")[0].href;
        var image = item.getElementsByTagName("img")[0];
        var caption = document.createElement('img');

        caption.src = image.src.replace('/Nav/','/Photos/small/').replace('.gif','.jpg');
        caption.alt = image.alt;
        caption.style.visibility = "hidden";
        item.appendChild(caption);
        
        if (window.location.href == url)
            caption.style.visibility = "visible";
        else {
            image.caption = caption;
            image.onmouseover = function() {
                document.getElementById("title").src = this.src.replace('/Nav/','/Nav/title/');
                high(this);
                this.caption.style.visibility = "visible";
                }
            image.onmouseout = function() {
                document.getElementById("title").src = '/img/null.gif';
                low(this);
                this.caption.style.visibility = "hidden";
                }
            }
        }

    items = document.getElementsByTagName("input");
    for (i = 0; i < items.length; i++) {
        var item = items[i];
        if (item.type == "image") {
            item.onmouseover = function() {high(this)};
            item.onmouseout = function() {low(this)};
        }
    }
}

function high(img) {
    img.src = img.src.replace('.gif','_on.gif');
}

function low(img) {
    img.src = img.src.replace('_on.gif','.gif')
}

// *** filter text boxes
function letter(event) {
    return !/\d/.test(String.fromCharCode(event.charCode ? event.charCode : event.keyCode));
}

function number(event) {
    return !/[A-Z a-z*#]/.test(String.fromCharCode(event.charCode ? event.charCode : event.keyCode));
}