(function(Mibew) {
    Mibew.APIFunctions.refreshButton = function(data) {
        // Refresh the button image
        var img = document.getElementById("mibew-agent-button").getElementsByTagName("img")[0];
        var originalSrc = img.src.replace(/&dummy=\d+/, '');
        img.src = originalSrc + "&dummy=" + (new Date()).getTime();

        // Hide the button if all popups are open or make it visible otherwise
        var visible = false;
        for(var key in Mibew.Objects.ChatPopups) {
            var popup = Mibew.Objects.ChatPopups[key];
            visible = visible || !popup.isOpened;
        }
        img.style.visibility = visible ? 'visible' : 'hidden';
    }
})(Mibew);