function OauthLandingHelper()

in Modules/System/OAuthClientAddIn/js/OAuthIntegration.js [70:162]
21 lines of code
5 McCabe index (conditional complexity)

function OauthLandingHelper(url, key, callback) {
    var w = top.window;
    var aadWindow = w.open(url, '_blank', 'width=972,height=904,location=no');

    if (aadWindow == null || aadWindow.closed || typeof aadWindow.closed === "undefined") {
        callback({
            error: "Popup blocked",
            desc: "There was a problem opening the authentication prompt. Check if it was blocked by a popup blocker."
        });
        return;
    }

    function storageEvent(e) {
        if (e.key === key && e.newValue) {
            w.removeEventListener('storage', storageEvent, false);
            action(e.newValue);
        }
    }

    function messageEvent(e) {
        if (e.data.clientId) {
            w.removeEventListener("message", messageEvent, false);
            action(e.data);
        }
    }

    function action(data) {
        var obj = data;
        if (typeof data === 'string') {
            obj = JSON.parse(data);
        }
        callback(obj);
        closeWindow();
    }

    function closeWindow() {
        try {
            w.removeEventListener("message", messageEvent, false);
            w.removeEventListener('storage', storageEvent, false);

            try {
                if (aadWindow.onbeforeunload) {
                    aadWindow.onbeforeunload = null;
                }
            } catch (e) { }

            if (w.localStorage.getItem(key)) {
                w.localStorage.removeItem(key);
            }

            aadWindow.close();
        } catch (ex) { }
    }

    function isCordova(win) {
        if (typeof win !== 'undefined' && win) {
            try {
                // this can throw a 'Permission denied" exception in IE11
                if (win.executeScript) { // if cordova. Is there a better way to detect?
                    return true;
                }
            }
            catch (e) {
                return false;
            }
        }

        return false;
    }

    if (isCordova(aadWindow)) {
        aadWindow.addEventListener("loadstop", function () {
            function getDataFromWindow() {
                aadWindow.executeScript(
                    { code: "localStorage.getItem('" + AuthStatusKey + "');" },
                    function (data) {
                        if (data && data.length > 0 && data[0]) {
                            var value = data[0];
                            clearInterval(loop);
                            action(value);
                        }
                    }
                );
            };
            var loop = setInterval(getDataFromWindow, 1000);
        });
    } else {
        w.removeEventListener('storage', storageEvent, false);
        w.addEventListener('storage', storageEvent, false);
        w.removeEventListener('message', messageEvent, false);
        w.addEventListener("message", messageEvent, false);
    }
}