alert_id = 0;

function add_alert(alert_class, alert_html) {
	var e, p, h, id;

	id = 'alert' + (alert_id ++);
	
	e = document.getElementById('alert');
	h = document.createElement('div');
	p = document.createElement('p');

	// Ensure that alert_class makes sense
	if (alert_class != 'good' && alert_class != 'idle')
		alert_class = 'bad';
	
	h.id = id;
	//p.appendChild(document.createTextNode(''));
	p.innerHTML = alert_html;
	h.appendChild(p);
	h.className = alert_class;
	e.appendChild(h);

	e.style.visibility = 'visible';
	e.style.display = 'block';

	return id;
}

function update_alert(alert_id, alert_class, alert_html) {
	var h;
	h = document.getElementById(alert_id);
	if (h != null) {
		h.setAttribute('class', alert_class);
		h.firstChild.innerHTML = alert_html;
	}
}