var menu = {

    init : function () {

        if(!document.getElementById) return;

        	var nav = document.getElementById('main_navigation');
        	var nav_items = nav.getElementsByTagName('a');
        	var il = nav_items.length;

            for (var i = 0; i < il; i++) {
            	    var current_item = nav_items[i];

            	    if(current_item.addEventListener) {
            	        current_item.addEventListener('mouseover', menu.mouseoverListener, false);
            	        current_item.addEventListener('mouseout', menu.mouseoutListener, false);
            	    } else if(current_item.attachEvent) {
            	        current_item.attachEvent('onmouseover', menu.mouseoverListener);
            	        current_item.attachEvent('onmouseout', menu.mouseoutListener);
            	    }

            }
    },

    mouseoverListener : function(e) {
        if(typeof menu == "undefined") return;
        var event = window.event ? window.event : e;
        var eventTarget = event.srcElement ? event.srcElement :  event.target;
        menu.toggleNavItem(eventTarget, event);
    },

    mouseoutListener : function(e) {
        if(typeof menu == "undefined") return;
        var event = window.event ? window.event : e;
        var eventTarget = event.srcElement ? event.srcElement :  event.target;
        menu.toggleNavItem(eventTarget, event);
    },

    toggleNavItem : function(item, event) {
        if(item.nodeName.toLowerCase() == 'img') {
            item = item.parentNode;
        }

        var parent_li = item.parentNode;
        var parent_a = parent_li.getElementsByTagName('a')[0];
        var navigation_img = parent_li.getElementsByTagName('img')[0]
        var isItemActive = parent_li.className.indexOf('active') != - 1;
        if(isItemActive) return;

        var current_src = navigation_img.getAttribute('src');

        var isItemHighligted = current_src.indexOf('highlighted') != - 1;
        if(opera && event.relatedTarget.nodeName.toLowerCase() == 'body') return;

        if(isItemHighligted) {
            var new_src = current_src.replace(/_highlighted/, "")
            parent_li.className = parent_li.className.replace(/hovered/, "");
        } else {
            var new_src = current_src.replace(/.png/, "_highlighted.png");
            parent_li.className += ' hovered';
        }

        navigation_img.setAttribute('src', new_src);
    }

}

function boxMinHeight() {

    var all_boxes = document.getElementsByClassName('box_inner', $('content'));
    var il = all_boxes.length;
    var bkg_pattern_height = 24;

    for( var i = il-1; i >= 0; i--) {
        var current_box = all_boxes[i];
        var box_vert_padding = parseInt(current_box.getStyle('paddingTop')) + parseInt(current_box.getStyle('paddingBottom'));
        var current_box_height = current_box.offsetHeight;//includes padding
        var delta = bkg_pattern_height - (current_box_height % bkg_pattern_height);

        var new_height = current_box_height + delta - box_vert_padding;
        current_box.style.minHeight = new_height + 'px';
        if(ie6) {
            current_box.style.height = new_height + 'px';
        }
    }

}