Alert bar to show information from the closest incident using cachet API

cachet-lert.js

document.addEventListener( 'DOMContentLoaded', function () {
    function cachetAlert(cachetUrl) {
        var createAlert = function(incident) {
            var divElement = document.createElement('div');
            divElement.id = 'cachet-alert';
            divElement.setAttribute('style', 'background-color: #FF3D2E; text-align: center; font-family: sans-serif;');
            divElement.innerHTML = '<a style="color: #fff; display: block; padding: 5px;" href="'+ cachetUrl +'" target="_blank">'+ incident.name +'</a>';
            document.body.insertBefore(divElement, document.body.children[0]);
        };

        var xmlhttp = new XMLHttpRequest();
        xmlhttp.onreadystatechange = function() {
            if (xmlhttp.readyState == XMLHttpRequest.DONE) {
                if (xmlhttp.status == 200) {
                    incident = JSON.parse(xmlhttp.responseText).data[0];
                    if (incident.status !== 4  && incident.status !== 0) {
                        createAlert(incident);
                    } else {
                        var xmlhttp2 = new XMLHttpRequest();
                        xmlhttp2.onreadystatechange = function() {
                            if (xmlhttp2.readyState == XMLHttpRequest.DONE) {
                                if (xmlhttp2.status == 200) {
                                    scheduledIncident = JSON.parse(xmlhttp2.responseText).data[0];
                                    if (new Date(scheduledIncident.scheduled_at) > new Date()) {
                                        createAlert(scheduledIncident);
                                    }
                                }
                            }
                        };

                        xmlhttp2.open('GET', cachetUrl + '/api/v1/incidents/?sort=id&order=desc&per_page=1&status=0', true);
                        xmlhttp2.send();
                    }
                }
            }
        };

        xmlhttp.open('GET', cachetUrl + '/api/v1/incidents/?sort=id&order=desc&per_page=1', true);
        xmlhttp.send();
    }
}, false );