var selected_menu;

function setSubMenu(src) {

	var exp = /\d+$/;
	var match;

	if (!selected_menu) {
		// ivm reset: zet id als selected indien classname ook 'top_menu_selected' bevat
		// alleen indien nog niet gezet
		var top = document.getElementById("main_menu_top");
		var topItems = top.getElementsByTagName("a");
		for (i=0 ; i < topItems.length ; i++ ) {
			if(topItems[i].className.match("top_menu_selected")) {
				
				match = topItems[i].id.match(exp);
				
				if (match) {
					selected_menu = match[0];
				}
			}	
		}
	}

	if(src) {
    	match = src.id.match(exp);

    	if (match) {

    		var id = match[0];
    	
    		// doorloop kinderen van submenu, zet klasse shown op hidden en vice versa indien id eindigt op gevonden id
    		var top = document.getElementById("main_menu_bottom");
    		var subItems = top.getElementsByTagName("span");
    		
    		for (i=0 ; i<subItems.length ; i++) {
    			
    			if (subItems[i].id == "ms_" + id) {
    				subItems[i].className = "shown";
    			} else {
    				subItems[i].className = "hidden";
    			}
    		}		
    	}
	}
}

function resetSubMenu() {

	if (selected_menu) {
		
		var top = document.getElementById("main_menu_bottom");
		if (top) {
			var subItems = top.getElementsByTagName("span");
			
			if (subItems) {
				for (i=0 ; i<subItems.length ; i++) {
					
					if (subItems[i]) {
						if (subItems[i].id == "ms_" + selected_menu) {
							subItems[i].className = "shown";
						}else {
							subItems[i].className = "hidden";
						}
					}
				}
			}
		}
	}
}