public async Task StartContinuousRecognition()

in FamilyNotes/Speech/SpeechManager.cs [145:228]
61 lines of code
6 McCabe index (conditional complexity)

        public async Task<bool> StartContinuousRecognition()
        {
            // Compiling a new grammar is potentially a high-latency operation,
            // and it's easy for various threads to call this method concurrently,
            // so use a sempahore to serialize access to this method. The semaphore
            // allows only one thread at a time to execute this code path.
            await Mutex.WaitAsync();

            if (IsInRecognitionSession)
            {
                // End the previous speech recognition session.
                await EndRecognitionSession();
            }
#if VERBOSE_DEBUG
            Debug.WriteLine( 
                "SpeechManager: Starting recognition session: {0}", 
                RecognitionMode );
#endif

            try
            {
                // If no mic is available, notify the user and reset mode to default.
                if (!await IsMicrophoneAvailable())
                {
                    if (RecognitionMode == SpeechRecognitionMode.CommandPhrases ||
                        RecognitionMode == SpeechRecognitionMode.Dictation)
                    {
                        var messageDialog = new Windows.UI.Popups.MessageDialog("Microphone is not available.");

                        messageDialog.Commands.Add(new UICommand("Go to settings...", async (command) =>
                        {
                            bool result = await Launcher.LaunchUriAsync(new Uri("ms-settings:privacy-microphone"));

                        }));
                        messageDialog.Commands.Add(new UICommand("Close", (command) => { }));
                        await messageDialog.ShowAsync();
                    }

                    RecognitionMode = SpeechRecognitionMode.Default;
                    Mutex.Release();
                    return false;
                }

                // Compile the grammar, based on the value of the RecognitionMode property.
                await CompileGrammar();

                // You can attach these event handlers only after the grammar is compiled. 
                SpeechRecognizer.ContinuousRecognitionSession.Completed += ContinuousRecognitionSession_Completed;
                SpeechRecognizer.ContinuousRecognitionSession.ResultGenerated += ContinuousRecognitionSession_ResultGenerated;

                // Start the recognition session. 
                await SpeechRecognizer.ContinuousRecognitionSession.StartAsync();

                // Keep track of the the recognition session's state.
                IsInRecognitionSession = true;
#if VERBOSE_DEBUG
                Debug.WriteLine( "SpeechManager: Continuous recognition session started" );
#endif
            }
            catch (Exception ex)
            {
                Debug.WriteLine("SpeechManager: Failed to start continuous recognition session.");

                var messageDialog = new Windows.UI.Popups.MessageDialog(
                    $"{ex.Message}",
                    "Failed to start continuous recognition session");

                messageDialog.Commands.Add(new UICommand("Go to settings...", async (command) =>
                {
                    bool result = await Launcher.LaunchUriAsync(new Uri("ms-settings:privacy-speech"));

                }));
                messageDialog.Commands.Add(new UICommand("Close", (command) => { }));
                await messageDialog.ShowAsync();

                Mutex.Release();
                return false;
            }
            finally
            {
                Mutex.Release();
            }
            return true;
        }