$(function(){
    function initEnrolment(elt) {
        elt = $(elt);
        elt.find("form.enrolment").on("submit", function() {
            elt.addClass("sending-request");
            var form = this;
            var url = form.action + "?ajax";
            $.post(url, $(form).serialize(), function(data) {
                elt.html(data);
                elt.removeClass("sending-request");
                initEnrolment(elt);
            });
            return false;
        });
    }

    $.each($(".activity-summary"), function(i, item) { initEnrolment(item) });
});