Bloom.UpdateVersionTable.LookupURLOfUpdate C# (CSharp) Method

        public UpdateTableLookupResult LookupURLOfUpdate()
        {
            if(String.IsNullOrEmpty(TextContentsOfTable))
            {
                Logger.WriteEvent("Enter LookupURLOfUpdate()");
                var client = new WebClient();
                {
                    try
                    {
                        Logger.WriteEvent("Channel is '" + ApplicationUpdateSupport.ChannelName + "'");
                        Logger.WriteEvent("UpdateVersionTable looking for UpdateVersionTable URL: " + GetUrlOfTable());
                        TextContentsOfTable = client.DownloadString(GetUrlOfTable());

                        //things like captive portals will return an html page rather than the text file what we asked for, if the user isn't
                        //logged in.
                        if(TextContentsOfTable.ToLower().Contains("<html"))
                        {
                            LogTableContents();
                            return new UpdateTableLookupResult() { Error = new WebException("Internet connection did not allow check for update.") };
                        }
                    }
                    catch(WebException e)
                    {
                        Logger.WriteEvent("***Error in LookupURLOfUpdate: " + e.Message);
                        if(e.Status == WebExceptionStatus.ProtocolError)
                        {
                            var resp = e.Response as HttpWebResponse;
                            if(resp != null && resp.StatusCode == HttpStatusCode.NotFound)
                            {
                                Logger.WriteEvent(String.Format("***Error: UpdateVersionTable failed to find a file at {0} (channel='{1}'",
                                    GetUrlOfTable(), ApplicationUpdateSupport.ChannelName));
                            }
                        }
                        else if(IsConnectionError(e))
                        {
                            Logger.WriteEvent("***Error: UpdateVersionTable could not connect to the server");
                        }
                        return new UpdateTableLookupResult() { Error = e };
                    }
                }
            }
            if(RunningVersion == default(Version))
            {
                RunningVersion = Assembly.GetExecutingAssembly().GetName().Version;
            }

            var parsingErrorMsg = String.Empty;
            try
            {
                //NB Programmers: don't change this to some OS-specific line ending, this is  file read by both OS's. '\n' is common to files edited on linux and windows.
                foreach(var line in TextContentsOfTable.Split(new[] { '\n' }, StringSplitOptions.RemoveEmptyEntries))
                {
                    if(line.TrimStart().StartsWith("#"))
                        continue; //comment

                    var parts = line.Split(new[] { ',' }, StringSplitOptions.RemoveEmptyEntries);
                    if(parts.Length != 3)
                    {
                        Logger.WriteEvent("***Error: UpdateVersionTable could not parse line {0} of this updateTableContent:", line);
                        LogTableContents();
                        throw new ApplicationException(line);
                    }
                    var lower = Version.Parse(parts[0]);
                    var upper = Version.Parse(parts[1]);
                    if(lower <= RunningVersion && upper >= RunningVersion)
                        return new UpdateTableLookupResult() { URL = parts[2].Trim() };
                }
                parsingErrorMsg = string.Format("{0} contains no record for this version of Bloom", GetUrlOfTable());
            }
            catch(ApplicationException e)
            {
                // BL-2654 Failure when reading upgrade table should not give a crash
                // In this case, a line of the UpdateVersionTable was not parseable
                // Put a message in the log and don't upgrade (and return a message that will get into a 'toast')
                parsingErrorMsg = "Could not parse a line of the UpdateVersionTable" + e.Message;
                Logger.WriteEvent(parsingErrorMsg);
            }
            catch(ArgumentException e)
            {
                // BL-2654 Failure when reading upgrade table should not give a crash
                // In this case, a version number in the UpdateVersionTable was not parseable
                // Put a message in the log and don't upgrade (and return a message that will get into a 'toast')
                parsingErrorMsg = "Could not parse a version number in the UpdateVersionTable" + e.Message;
                Logger.WriteEvent(parsingErrorMsg);
            }
            return new UpdateTableLookupResult() { URL = String.Empty, Error = new WebException(parsingErrorMsg) };
        }

 public void LookupURLOfUpdate_NoLineForDesiredVersion_ReportsError()
 {
     var t = new UpdateVersionTable();
     t.TextContentsOfTable = @"0.0.0,3.1.99999, http://first.com/first";
     t.RunningVersion = Version.Parse("3.2.0");
     var lookupResult = t.LookupURLOfUpdate();
     Assert.That(lookupResult.URL, Is.Null.Or.Empty);
     Assert.That(lookupResult.Error.Message, Is.EqualTo("http://bloomlibrary.org/channels/UpgradeTableTestChannel.txt contains no record for this version of Bloom"));
 }