TASK 3 milestone 1: webcam capture (MediaCapture CPU-first, CameraManager refcount, picker, clip/mirror, schema v2, tests)

2026-08-06 14:35:34 -07:00
parent d97b5d375c
commit 98cdc4b3f4
23 changed files with 1099 additions and 40 deletions
@@ -0,0 +1,86 @@
+using System.Collections.ObjectModel;
+using System.Windows.Input;
+using ytLive.Helpers;
+using ytLive.Services;
+
+namespace ytLive.ViewModels;
+
+public class CameraPickerCandidate
+{
+    public CameraDeviceInfo Device { get; }
+    public string Name => Device.DisplayName;
+
+    public CameraPickerCandidate(CameraDeviceInfo device)
+    {
+        Device = device;
+    }
+}
+
+public class CameraPickerViewModel : ViewModelBase
+{
+    private readonly ICameraEnumerator _enumerator;
+    private CameraPickerCandidate? _selectedCamera;
+    private bool _isLoading = true;
+
+    public ObservableCollection<CameraPickerCandidate> Cameras { get; } = new();
+
+    public bool IsLoading
+    {
+        get => _isLoading;
+        private set => SetProperty(ref _isLoading, value);
+    }
+
+    public bool HasCameras => !IsLoading && Cameras.Count > 0;
+    public bool NoCameras => !IsLoading && Cameras.Count == 0;
+
+    public CameraPickerCandidate? SelectedCamera
+    {
+        get => _selectedCamera;
+        set
+        {
+            if (SetProperty(ref _selectedCamera, value))
+                CommandManager.InvalidateRequerySuggested();
+        }
+    }
+
+    public ICommand UseSelectedCommand { get; }
+    public ICommand CancelCommand { get; }
+
+    public event Action<CameraDeviceInfo>? UseRequested;
+    public event Action? CancelRequested;
+
+    public CameraPickerViewModel(ICameraEnumerator enumerator)
+    {
+        _enumerator = enumerator;
+        UseSelectedCommand = new RelayCommand(
+            _ => { if (SelectedCamera != null) UseRequested?.Invoke(SelectedCamera.Device); },
+            _ => SelectedCamera != null);
+        CancelCommand = new RelayCommand(_ => CancelRequested?.Invoke());
+        _ = LoadAsync();
+    }
+
+    private async Task LoadAsync()
+    {
+        IsLoading = true;
+        try
+        {
+            var devices = await _enumerator.GetCamerasAsync();
+            Cameras.Clear();
+            foreach (var device in devices)
+                Cameras.Add(new CameraPickerCandidate(device));
+            if (Cameras.Count > 0)
+                SelectedCamera = Cameras[0];
+        }
+        catch (Exception ex)
+        {
+            AppLog.Write($"CameraPickerViewModel: enumerating cameras failed: {ex.Message}");
+        }
+        finally
+        {
+            IsLoading = false;
+            OnPropertyChanged(nameof(HasCameras));
+            OnPropertyChanged(nameof(NoCameras));
+            CommandManager.InvalidateRequerySuggested();
+        }
+    }
+}