Audio-Router/Audio Router WPF/MainWindow.xaml.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using Windows.UI.Core;
using System.Windows.Shapes;
using Windows.Devices.Enumeration;
using Windows.Media.Audio;
using System.Windows.Threading;
using Windows.Media.Devices;
using Windows.Media.Render;
using Windows.Media.Capture;

namespace Audio_Router_WPF
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        //AudioGraph graph;
        // The list of audio devices
        DeviceInformationCollection sourceDevices;
        DeviceInformationCollection targetDevices;

        #pragma warning disable CS8618 // Non-nullable field must contain a non-null value when exiting constructor. Consider declaring as nullable. (these fields cannot be assigned 
        public MainWindow()
        { 
            InitializeComponent();
            
        }
        protected override void OnInitialized(EventArgs e)
        {
            base.OnInitialized(e);
            _ = Task.Run(() => FindAudioSources());
        }
        private async void AddAudioGraphButton_Click(object sender, RoutedEventArgs e)
        {
            await CreateAudioGraph();
        }

        private async Task FindAudioSources()
        {
            // First, clear the lists
            Dispatcher.Invoke(() =>
            {
                InputAudioComboBox.Items.Clear();
                OutputAudioComboBox.Items.Clear();
            }, DispatcherPriority.Normal);
            // Perform this on our spawned thread, as the operation is asynchronous-synchronous await
            sourceDevices = await DeviceInformation.FindAllAsync(MediaDevice.GetAudioCaptureSelector());
            targetDevices = await DeviceInformation.FindAllAsync(MediaDevice.GetAudioRenderSelector());

            DeviceInformation defaultOutput = await DeviceInformation.CreateFromIdAsync(MediaDevice.GetDefaultAudioRenderId(AudioDeviceRole.Default));
            DeviceInformation defaultInput = await DeviceInformation.CreateFromIdAsync(MediaDevice.GetDefaultAudioCaptureId(AudioDeviceRole.Default));


            Dispatcher.Invoke(() =>
            {
                // Set the Input device
                for (int i = 0; i < sourceDevices.Count; i++)
                {
                    if (sourceDevices[i].Id == defaultInput.Id)
                    {
                        _ = InputAudioComboBox.Items.Add(sourceDevices[i].Name + " (Default Device)");
                        InputAudioComboBox.SelectedIndex = i;
                    }
                    else
                    {
                        _ = InputAudioComboBox.Items.Add(sourceDevices[i].Name);
                    }
                }
                // _ = InputAudioComboBox.Items.Add("--Output nodes--"); // This requires further work, implementing W
                for (int i = 0; i < targetDevices.Count; i++)
                {
                    if (targetDevices[i].Id == defaultOutput.Id)
                    {
                        _ = OutputAudioComboBox.Items.Add(targetDevices[i].Name + " (Default Device)");
                        //_ = InputAudioComboBox.Items.Add(targetDevices[i].Name + " (Default Device)");
                        OutputAudioComboBox.SelectedIndex = i;
                    }
                    else
                    {
                        _ = OutputAudioComboBox.Items.Add(targetDevices[i].Name);
                        //_ = InputAudioComboBox.Items.Add(targetDevices[i].Name);
                    }
                }
            });
        }


        private async Task CreateAudioGraph()
        {
            App.displayRequest.RequestActive();
            bool isInputDevice = true;
            DeviceInformation inputDevice;
            if (InputAudioComboBox.SelectedIndex < sourceDevices.Count)
            {
                isInputDevice = true;
                inputDevice = sourceDevices[InputAudioComboBox.SelectedIndex];
            }
            else if (InputAudioComboBox.SelectedIndex == sourceDevices.Count) return;
            else
            {
                isInputDevice = false;
                inputDevice = targetDevices[InputAudioComboBox.SelectedIndex - (sourceDevices.Count + 1)];
            }
            DeviceInformation outputDevice = targetDevices[OutputAudioComboBox.SelectedIndex];
            
            AudioGraphSettings settings = LowLatencyCheckbox.IsChecked == true
                ? new AudioGraphSettings(AudioRenderCategory.Media)
                {
                    QuantumSizeSelectionMode = QuantumSizeSelectionMode.ClosestToDesired,
                    DesiredSamplesPerQuantum = 10,
                    PrimaryRenderDevice = outputDevice,
                    DesiredRenderDeviceAudioProcessing = Windows.Media.AudioProcessing.Raw,
                    EncodingProperties = new Windows.Media.MediaProperties.AudioEncodingProperties()
                    {
                        Subtype = "Float",
                        SampleRate = 128000, // Manually set to 128 000 samples/second so that the delay is significantly reduced
                        ChannelCount = 2,
                        BitsPerSample = 32,
                        Bitrate = 3072000
                    }
                }
                : new AudioGraphSettings(AudioRenderCategory.Media)
                {
                    PrimaryRenderDevice = outputDevice
                };
            CreateAudioGraphResult result = await AudioGraph.CreateAsync(settings);
            AudioGraph ag = result.Graph;

            if (result.Status != AudioGraphCreationStatus.Success)
            {
                return;
            }

            CreateAudioDeviceInputNodeResult deviceInputNodeResult = await ag.CreateDeviceInputNodeAsync(MediaCategory.Other, ag.EncodingProperties, inputDevice);
            //CreateAudioDeviceInputNodeResult deviceInputNodeResult = await ag.CreateDeviceInputNodeAsync(,,);
            //AudioFrameInputNode g = ag.CreateFrameInputNode();
            if (deviceInputNodeResult.Status != AudioDeviceNodeCreationStatus.Success)
            {
                // Fail-safe, switch to using the default encoding properties
                settings = new AudioGraphSettings(AudioRenderCategory.Media)
                {
                    PrimaryRenderDevice = outputDevice
                };
                result = await AudioGraph.CreateAsync(settings);
                ag = result.Graph;

                if (result.Status != AudioGraphCreationStatus.Success)
                {
                    return;
                }
                deviceInputNodeResult = await ag.CreateDeviceInputNodeAsync(MediaCategory.Other, ag.EncodingProperties, inputDevice);
                if (deviceInputNodeResult.Status != AudioDeviceNodeCreationStatus.Success)
                {
                    return;
                }
            }
            // Create the device output node connection
            CreateAudioDeviceOutputNodeResult deviceOutputNodeResult = await ag.CreateDeviceOutputNodeAsync();
            //deviceOutputNodeResult.DeviceOutputNode.Creat
            if (deviceOutputNodeResult.Status != AudioDeviceNodeCreationStatus.Success)
            {
                return;
            }
            deviceInputNodeResult.DeviceInputNode.AddOutgoingConnection(deviceOutputNodeResult.DeviceOutputNode);
            // appMediaControls.PlaybackStatus = MediaPlaybackStatus.Playing;
            ag.Start();
            AudioGraphConnection graphConnection = new AudioGraphConnection(ag, deviceOutputNodeResult.DeviceOutputNode, deviceInputNodeResult.DeviceInputNode, Dispatcher);
            App.appRef.audioGraphConnections.Add(graphConnection);
            // Hold a reference to the created button; when clicked we must also ensure we remove this visual element from the grid display
            Grid renderGrid = graphConnection.GetAsDisplayItem(out Button visualButton);
            CreatedGraphs.Children.Add(renderGrid);
            // Inline decl to add a second listener to the click event - will remove the grid from the display
            void handler(object sender, RoutedEventArgs e)
            {
                visualButton.Click -= handler;
                DestroyVisualElement(ref renderGrid);
            }

            visualButton.Click += handler;
        }

        private void DestroyVisualElement(ref Grid element)
        {
            CreatedGraphs.Children.Remove(element);
            element = null;
        }

    }
}