ytLlive/ViewModels/MainViewModel.cs

using System.Collections.ObjectModel;
using System.Windows;
using System.Windows.Input;
using System.Windows.Threading;
using ytLive.Helpers;
using ytLive.Models;
using ytLive.Services;

namespace ytLive.ViewModels;

public class MainViewModel : ViewModelBase
{
    private readonly YouTubeAuthService _youtubeAuth;
    private readonly YouTubeStreamService _youtubeStream;
    private readonly YouTubeChatService _youtubeChat;
    private readonly DispatcherTimer _liveTimer;

    private Scene? _activeScene;
    private StreamStatus _streamStatus = StreamStatus.Offline;
    private StreamHealth _currentHealth = new();
    private string _streamTitle = string.Empty;
    private string _streamDescription = string.Empty;
    private string _streamVisibility = "Public";
    private string _windowTitle = "ytLive";
    private string _topBarBackground = "#16213e";
    private string _previewGlowBrush = "Transparent";
    private Thickness _previewGlowThickness = new(0);
    private string _liveElapsedText = "00:00:00";
    private double _livePulseOpacity = 1.0;
    private TimeSpan _liveElapsed;

    public ObservableCollection<Scene> Scenes { get; } = new();
    public ObservableCollection<ChatMessage> ChatMessages { get; } = new();

    public Scene? ActiveScene
    {
        get => _activeScene;
        set => SetProperty(ref _activeScene, value);
    }

    public StreamStatus StreamStatus
    {
        get => _streamStatus;
        set
        {
            if (SetProperty(ref _streamStatus, value))
            {
                OnPropertyChanged(nameof(IsOffline));
                OnPropertyChanged(nameof(IsLive));
                OnPropertyChanged(nameof(LiveIndicatorVisible));
                UpdateLiveVisuals();
            }
        }
    }

    public bool IsOffline => StreamStatus == StreamStatus.Offline;
    public bool IsLive => StreamStatus == StreamStatus.Streaming;
    public bool LiveIndicatorVisible => IsLive;

    public StreamHealth CurrentHealth
    {
        get => _currentHealth;
        set => SetProperty(ref _currentHealth, value);
    }

    public string StreamTitle
    {
        get => _streamTitle;
        set => SetProperty(ref _streamTitle, value);
    }

    public string StreamDescription
    {
        get => _streamDescription;
        set => SetProperty(ref _streamDescription, value);
    }

    public string StreamVisibility
    {
        get => _streamVisibility;
        set => SetProperty(ref _streamVisibility, value);
    }

    public string WindowTitle
    {
        get => _windowTitle;
        set => SetProperty(ref _windowTitle, value);
    }

    public string TopBarBackground
    {
        get => _topBarBackground;
        set => SetProperty(ref _topBarBackground, value);
    }

    public string PreviewGlowBrush
    {
        get => _previewGlowBrush;
        set => SetProperty(ref _previewGlowBrush, value);
    }

    public Thickness PreviewGlowThickness
    {
        get => _previewGlowThickness;
        set => SetProperty(ref _previewGlowThickness, value);
    }

    public string LiveElapsedText
    {
        get => _liveElapsedText;
        set => SetProperty(ref _liveElapsedText, value);
    }

    public double LivePulseOpacity
    {
        get => _livePulseOpacity;
        set => SetProperty(ref _livePulseOpacity, value);
    }

    // Commands
    public ICommand AddSceneCommand { get; }
    public ICommand RemoveSceneCommand { get; }
    public ICommand StartStreamCommand { get; }
    public ICommand EndStreamCommand { get; }

    public MainViewModel()
    {
        _youtubeAuth = new YouTubeAuthService("", "");  // TODO: load from config
        _youtubeStream = new YouTubeStreamService(_youtubeAuth);
        _youtubeChat = new YouTubeChatService(_youtubeAuth);

        _youtubeChat.MessageReceived += OnChatMessageReceived;

        _liveTimer = new DispatcherTimer { Interval = TimeSpan.FromSeconds(1) };
        _liveTimer.Tick += OnLiveTimerTick;

        AddSceneCommand = new RelayCommand(_ => AddScene());
        RemoveSceneCommand = new RelayCommand(scene => RemoveScene(scene as Scene));
        StartStreamCommand = new RelayCommand(_ => BeginGoLive());
        EndStreamCommand = new RelayCommand(_ => StopStream(), _ => IsLive);

        // Start with a default scene
        AddScene("Scene 1");
    }

    private void AddScene(string? name = null)
    {
        var scene = new Scene { Name = name ?? $"Scene {Scenes.Count + 1}" };
        Scenes.Add(scene);
        ActiveScene = scene;
    }

    private void RemoveScene(Scene? scene)
    {
        if (scene == null) return;
        Scenes.Remove(scene);
        if (ActiveScene == scene)
            ActiveScene = Scenes.FirstOrDefault();
    }

    private void OnChatMessageReceived(ChatMessage message)
    {
        System.Windows.Application.Current.Dispatcher.Invoke(() =>
        {
            ChatMessages.Add(message);
            if (ChatMessages.Count > 500)
                ChatMessages.RemoveAt(0);
        });
    }

    private void BeginGoLive()
    {
        var dialog = new GoLiveViewModel();
        var window = new ytLive.GoLiveWindow(dialog) { Owner = System.Windows.Application.Current.MainWindow };
        if (window.ShowDialog() == true)
        {
            StreamTitle = dialog.StreamTitle;
            StreamDescription = dialog.StreamDescription;
            StreamVisibility = dialog.Visibility;
            WindowTitle = string.IsNullOrWhiteSpace(dialog.StreamTitle)
                ? "ytLive"
                : $"{dialog.StreamTitle} — ytLive";
            StreamStatus = StreamStatus.Streaming;
        }
    }

    private void StopStream()
    {
        StreamStatus = StreamStatus.Offline;
        WindowTitle = "ytLive";
    }

    private void UpdateLiveVisuals()
    {
        var live = IsLive;
        TopBarBackground = live ? "#e94560" : "#16213e";
        PreviewGlowBrush = live ? "#e94560" : "Transparent";
        PreviewGlowThickness = live ? new Thickness(3) : new Thickness(0);

        if (live)
        {
            _liveElapsed = TimeSpan.Zero;
            LiveElapsedText = "00:00:00";
            LivePulseOpacity = 1.0;
            _liveTimer.Start();
        }
        else
        {
            _liveTimer.Stop();
            LiveElapsedText = "00:00:00";
            LivePulseOpacity = 1.0;
        }
    }

    private void OnLiveTimerTick(object? sender, EventArgs e)
    {
        _liveElapsed = _liveElapsed.Add(TimeSpan.FromSeconds(1));
        LiveElapsedText = _liveElapsed.ToString(@"hh\:mm\:ss");
        LivePulseOpacity = LivePulseOpacity > 0.5 ? 0.35 : 1.0;
    }
}