EonaCat.VolumeMixer/EonaCat.VolumeMixer.Tester.WPF/MainWindow.xaml.cs

using EonaCat.VolumeMixer.Managers;
using EonaCat.VolumeMixer.Models;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Runtime.CompilerServices;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media.Imaging;
using System.Windows.Threading;

namespace EonaCat.VolumeMixer.Tester.WPF
{
    // This file is part of the EonaCat project(s) which is released under the Apache License.
    // See the LICENSE file or go to https://EonaCat.com/License for full license details.
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public ObservableCollection<AudioDeviceViewModel> Devices { get; } = new();
        public ObservableCollection<AudioSessionViewModel> Sessions { get; } = new();
        private VolumeMixerManager _manager;
        private AudioDevice _currentDevice;
        private readonly DispatcherTimer _pollTimer = new() { Interval = TimeSpan.FromMilliseconds(250) };

        private readonly DispatcherTimer _refreshTimer = new() { Interval = TimeSpan.FromSeconds(10) };

        public MainWindow()
        {
            InitializeComponent();
            DeviceSelector.ItemsSource = Devices;
            SessionList.ItemsSource = Sessions;
            _refreshTimer.Tick += (s, e) => RefreshSessions().ConfigureAwait(false);
            _pollTimer.Tick += PollTimer_Tick;
            LoadDevices();
        }

        private async void PollTimer_Tick(object sender, EventArgs e)
        {
            foreach (var sessionVm in Sessions)
            {
                await sessionVm.PollRefreshAsync();
            }
        }

        private async void LoadDevices()
        {
            _manager = new VolumeMixerManager();
            var devices = await _manager.GetAudioDevicesAsync(DataFlow.All);
            Devices.Clear();
            foreach (var device in devices)
            {
                Devices.Add(new AudioDeviceViewModel(device));
            }

            var defaultDevice = await _manager.GetDefaultAudioDeviceAsync();
            DeviceSelector.SelectedItem = Devices.FirstOrDefault(d => d.Id == defaultDevice.Id);
        }

        private async void DeviceSelector_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            if (DeviceSelector.SelectedItem is not AudioDeviceViewModel selectedVm)
            {
                _refreshTimer.Stop();
                _pollTimer.Stop();
                return;
            }

            _currentDevice = selectedVm.Device;
            await RefreshSessions();
            _refreshTimer.Start();
            _pollTimer.Start();
        }

        private async Task RefreshSessions()
        {
            if (_currentDevice == null)
            {
                return;
            }

            var sessions = await _currentDevice.GetAudioSessionsAsync();
            Sessions.Clear();
            foreach (var session in sessions)
            {
                var vm = new AudioSessionViewModel(session);
                await vm.RefreshAsync();
                Sessions.Add(vm);
            }
        }

        private void Slider_PreviewMouseDown(object sender, System.Windows.Input.MouseButtonEventArgs e)
        {
            if (((FrameworkElement)sender).DataContext is AudioSessionViewModel vm)
            {
                vm.IsUserChangingVolume = true;
            }
        }

        private void Slider_PreviewMouseUp(object sender, System.Windows.Input.MouseButtonEventArgs e)
        {
            if (((FrameworkElement)sender).DataContext is AudioSessionViewModel vm)
            {
                vm.IsUserChangingVolume = false;
                _ = vm.RefreshAsync();
            }
        }

        private void Slider_PreviewTouchDown(object sender, System.Windows.Input.TouchEventArgs e)
        {
            if (((FrameworkElement)sender).DataContext is AudioSessionViewModel vm)
            {
                vm.IsUserChangingVolume = true;
            }
        }

        private void Slider_PreviewTouchUp(object sender, System.Windows.Input.TouchEventArgs e)
        {
            if (((FrameworkElement)sender).DataContext is AudioSessionViewModel vm)
            {
                vm.IsUserChangingVolume = false;
                _ = vm.RefreshAsync();
            }
        }
    }

    public class AudioDeviceViewModel
    {
        public AudioDevice Device { get; }
        public string Display => Device.Name;
        public string Id => Device.Id;
        public BitmapImage Icon => new BitmapImage(new Uri("pack://application:,,,/Resources/" + (Device.DeviceType == DeviceType.Microphone ? "mic.png" : "speaker.png")));

        public AudioDeviceViewModel(AudioDevice device)
        {
            Device = device;
        }
    }

    public class AudioSessionViewModel : INotifyPropertyChanged
    {
        private readonly AudioSession _session;
        private float _volume;
        private bool _isMuted;

        public string DisplayName => _session.DisplayName;

        private bool _isUserChangingVolume;

        public bool IsUserChangingVolume
        {
            get => _isUserChangingVolume;
            set
            {
                if (_isUserChangingVolume != value)
                {
                    _isUserChangingVolume = value;
                    OnPropertyChanged();
                }
            }
        }


        public float Volume
        {
            get => _volume;
            set
            {
                if (Math.Abs(_volume - value) > 0.01)
                {
                    value = Math.Clamp(value, 0, 1);

                    if (_volume == value)
                    {
                        return;
                    }

                    _volume = value;
                    OnPropertyChanged();
                    _ = SetVolumeSafeAsync(value);
                }
            }
        }

        private async Task SetVolumeSafeAsync(float value)
        {
            try
            {
                await _session.SetVolumeAsync(value);
            }
            catch
            {
                // Do nothing
            }
        }


        public bool IsMuted
        {
            get => _isMuted;
            set
            {
                if (_isMuted != value)
                {
                    _isMuted = value;
                    _ = _session.SetMuteAsync(value);
                    OnPropertyChanged();
                }
            }
        }

        public async Task PollRefreshAsync()
        {
            if (!IsUserChangingVolume)
            {
                float currentVolume = await _session.GetVolumeAsync();
                if (Math.Abs(currentVolume - _volume) > 0.01)
                {
                    _volume = currentVolume;
                    OnPropertyChanged(nameof(Volume));
                }

                bool currentMute = await _session.GetMuteAsync();
                if (currentMute != _isMuted)
                {
                    _isMuted = currentMute;
                    OnPropertyChanged(nameof(IsMuted));
                }
            }
        }


        public AudioSessionViewModel(AudioSession session)
        {
            _session = session;
        }

        public async Task RefreshAsync()
        {
            Volume = await _session.GetVolumeAsync();
            IsMuted = await _session.GetMuteAsync();
        }

        public event PropertyChangedEventHandler PropertyChanged;
        protected void OnPropertyChanged([CallerMemberName] string propertyName = null) => PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }
}