Azure Service Bus Tester

using System;
using System.Collections.Generic;
using System.Configuration;
using System.Linq;
using System.Threading;
using System.Windows.Forms;
using Microsoft.ServiceBus;

namespace RKiss.Tools.ServiceBusTester.Dialogs
{
    public partial class PublisherDialog : Form
    {
        List<ServiceBusConnection> namespaces = null;
        string defaultTopic = null;
        string servicebus = "servicebus.windows.net";

        public PublisherDialog(List<ServiceBusConnection> listOfConnections, ServiceBusDefaults defaults)
        {
            InitializeComponent();

            if (ConfigurationManager.AppSettings.AllKeys.Contains("servicebus"))
            {
                servicebus = ConfigurationManager.AppSettings["servicebus"];
            }

            this.textBoxPublisherId.Text = Guid.NewGuid().ToString();
            this.namespaces = listOfConnections;
            this.defaultTopic = defaults.Topic;
         
            string[] ns = (from n in namespaces select n.Namespace).ToArray<string>();

            if (ns != null && ns.Count() > 0)
            {
                this.comboBoxNamespace.Items.AddRange(ns);
                this.comboBoxNamespace.SelectedItem = ns.Contains(defaults.Namespace) ? defaults.Namespace : ns[0];
                this.comboBoxNamespace.SelectedIndexChanged += new EventHandler(comboBoxNamespace_SelectedIndexChanged);
              
                this.comboBoxTopic.Items.Add(this.defaultTopic);
                this.comboBoxTopic.SelectedIndex = 0;

                this.buttonOK.Enabled = false;
                this.RefreshWorker_Namespace();
            }
            else
            {
                MessageBox.Show("No Connection to the Service Bus", "Add Publisher", MessageBoxButtons.OK, MessageBoxIcon.Warning);
                this.DialogResult = System.Windows.Forms.DialogResult.Abort;
                this.Close();
            }           
        }

        void comboBoxNamespace_SelectedIndexChanged(object sender, EventArgs e)
        {
            this.RefreshWorker_Namespace();
        }

        #region Public
        public string NamespaceAddress
        {
            get { return string.Format("sb://{0}.{1}", this.comboBoxNamespace.Text, servicebus); }
        }

        public string TopicAddress
        {
            get { return string.Format("sb://{0}.{1}/{2}", this.comboBoxNamespace.Text, this.servicebus, this.comboBoxTopic.Text); }
        }

        public string PublisherName
        {
            get { return string.Format("{0}.{1}.{2}", this.comboBoxNamespace.Text, this.comboBoxTopic.Text, this.textBoxPublisherId.Text); }
        }

        public ServiceBusConnection ServiceBusConnection
        {
            get { return this.namespaces.Where(c => c.Namespace == this.comboBoxNamespace.Text).FirstOrDefault(); }
        }
        #endregion

        private string[] GetTopics(string sbNamespace)
        {
            try
            {
                var ns = namespaces.FirstOrDefault(n => n.Namespace == sbNamespace);
                if (ns == null)
                    throw new Exception(string.Format("Please, make a connection to the '{0}' namespace", sbNamespace));

                var token = TokenProvider.CreateSharedSecretTokenProvider(ns.IssuerName, ns.IssuerSecret);
                string namespaceaddress = string.Format("sb://{0}.{1}", sbNamespace, this.servicebus);

                var namespaceClient = new Microsoft.ServiceBus.NamespaceManager(namespaceaddress, token);
                var topics = namespaceClient.GetTopics();

                return (from t in topics select t.Path).ToArray();
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message, "Get Topics", MessageBoxButtons.OK, MessageBoxIcon.Error);
                return null;
            }
        }

        private void buttonRefresh_Click(object sender, EventArgs e)
        {
            this.RefreshWorker_Namespace();
        }

        private void RefreshWorker_Namespace()
        {
            ThreadPool.QueueUserWorkItem(delegate(object state)
            {
                string selectedNamespace = null;
                string selectedTopic = null;

                this.InvokeEx(delegate()
                {
                    selectedNamespace = this.comboBoxNamespace.Text;
                    selectedTopic = this.comboBoxTopic.Text;

                    this.groupBoxSB.Enabled = false;
                    this.buttonOK.Enabled = false;
                    this.buttonRefresh.Enabled = false;
                    this.buttonRefresh.Text = "Loading";

                    this.comboBoxTopic.Items.Clear();
                });

                using (var progress = new ProgressButton(this, this.buttonRefresh, 1, 0))
                {
                    var topics = this.GetTopics(selectedNamespace);
                    if (topics != null && topics.Count() > 0)
                    {
                        this.InvokeEx(delegate()
                        {
                            this.comboBoxTopic.Items.AddRange(topics);
                            this.comboBoxTopic.SelectedItem = this.comboBoxTopic.Items.Contains(selectedTopic) ? selectedTopic : this.comboBoxTopic.Items[0];
                            selectedTopic = this.comboBoxTopic.Text;

                            this.buttonOK.Enabled = this.comboBoxTopic.SelectedItem != null;
                        });
                    }

                    this.InvokeEx(delegate()
                    {
                        this.groupBoxSB.Enabled = true;
                        this.buttonRefresh.Text = "Refresh";
                        this.buttonRefresh.Enabled = true;
                    });
                }
            });
        }     
    }
}