infineon_cs_hmi/uniper_hmi/UniperHMI/MainWindowVM.cs

using CommunityToolkit.Mvvm.ComponentModel;
using CommunityToolkit.Mvvm.Input;
using CommunityToolkit.Mvvm.Messaging;
using Heisig.HMI.AdsManager;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using System.Windows;
using System.Windows.Controls;
using TcEventLoggerAdsProxyLib;

namespace UniperHMI;

public sealed partial class MainWindowVM : ObservableObject, IRecipient<NavigateMessage>, IDisposable
{

    [ObservableProperty]
    private StringControlButtonVM dummyStringVM;

    [ObservableProperty]
    private Page currentPage;

    [ObservableProperty]
    private bool canNavigateBack;

    [ObservableProperty]
    private Visibility statusBarVisible;

    [ObservableProperty]
    private string breadcrumb;


    private readonly IAdsManager _adsManager;
    private readonly IConfiguration _config;
    private readonly TcEventLogger _eventlogger;

    // Last active event
    [ObservableProperty]
    private string currentActiveEvent = "";

    private readonly object _lock = new();

    // Empty page
    private readonly Page _emptyPage;

    // Last navigate message
    private readonly Stack<NavigateMessage> _messageStack = new();
    NavigateMessage? _currentMessage;

    // Events page view model
    [ObservableProperty]
    EventsPageVM _eventsPageVM;

    // Settings page viem model
    SettingsPageVM? _settingsPageVM;

    // Hot Coolplate page view model
    HotCoolPlatePageVM? _hotCoolplatePageVM;

    // Chuck Magazin page view model
    ChuckMagazinPageVM? _chuckMagazinPageVM;

	// Kuka Robot page view model
	KukaRobotPageVM? _kukaRobotPageVM;

    public MainWindowVM(IAdsManager adsManager, IConfiguration config, TcEventLogger eventLogger)
    {
        _adsManager = adsManager;
        _config = config;

        // Create dummy string
        DummyStringVM = new StringControlButtonVM();

        // Create empty page
        _emptyPage = new();

        // Create events page viewmodel
        _eventlogger = eventLogger;
        _eventsPageVM = new(_eventlogger);

        CurrentPage = _emptyPage;
        _currentMessage = new NavigateMessage("", typeof(Page));
        _messageStack.Push(_currentMessage);

        WeakReferenceMessenger.Default.Register<NavigateMessage>(this);

        breadcrumb = "";
    }

    [RelayCommand]
    private void SettingsWindow()
    {
        StatusBarVisible = Visibility.Visible;
        _messageStack.Clear();
        NavigateMessage message = new("", typeof(SettingsPage));
        Receive(message);
    }

    [RelayCommand]
    public void AutomaticModeClicked()
    {
        StatusBarVisible = Visibility.Visible;
        _messageStack.Clear();
        _currentMessage = new NavigateMessage("", typeof(Page));
        NavigateMessage message = new(_config["AutomaticModeVarName"]!, typeof(AutomaticModePage));
        Receive(message);
    }

    [RelayCommand]
    public void ManualModeClicked()
    {
        StatusBarVisible = Visibility.Visible;
        _messageStack.Clear();
        _currentMessage = new NavigateMessage("", typeof(Page));
        NavigateMessage message = new("", typeof(BatteryOverviewPage));
        Receive(message);
    }

    [RelayCommand]
    public void EventsListClicked()
    {
        StatusBarVisible = Visibility.Collapsed;
        _messageStack.Clear();
        _currentMessage = new NavigateMessage("", typeof(Page));
        NavigateMessage message = new("", typeof(EventsPage));
        Receive(message);
    }
    [RelayCommand]
    public void KukaRobotClicked()
    {
        StatusBarVisible = Visibility.Visible;
        _messageStack.Clear();
        _currentMessage = new NavigateMessage("", typeof(Page));
        NavigateMessage message = new(_config["KukaRobotVarName"]!, typeof(KukaRobotPage));
        Receive(message);
    }
	[RelayCommand]
	public void HotCoolplateClicked()
	{
		StatusBarVisible = Visibility.Visible;
		_messageStack.Clear();
		_currentMessage = new NavigateMessage("", typeof(Page));
		NavigateMessage message = new(_config["HotCoolplateVarName"]!, typeof(HotCoolPlatePage));
		Receive(message);
	}

	[RelayCommand]
	public void ChuckMagazinClicked()
	{
		StatusBarVisible = Visibility.Visible;
		_messageStack.Clear();
		_currentMessage = new NavigateMessage("", typeof(Page));
		NavigateMessage message = new(_config["ChuckMagazinVarName"]!, typeof(ChuckMagazinPage));
		Receive(message);
	}

	[RelayCommand]
    public void NavigateBack()
    {
        if (_messageStack.Count == 0)
        {
            CanNavigateBack = false;
            return;
        }
            
        _currentMessage = _messageStack.Pop();

        // Update if we can use the navigate back button
        if (_messageStack.Count > 0)
            CanNavigateBack = true;
        else
        {
            StatusBarVisible = Visibility.Visible;
            CanNavigateBack = false;
        }
            

        // Remove last two entrys from Breadcrumbs
        int index = -1;
        for (int i = 0; i < 2; i++)
        {
            index = Breadcrumb.LastIndexOf('>');
            if (index != -1)
                Breadcrumb = Breadcrumb[..index];
        }

        // Navigate to page
        Navigate(_currentMessage);
    }

    // Only use for forward traversal!
    public void Receive(NavigateMessage message)
    {
        // Only change page if its a new page type
        if (CurrentPage.GetType() == message.type)
            return;

        // Push current message
        if (_currentMessage != null)
            _messageStack.Push(_currentMessage);

        // Save current message for later push
        _currentMessage = message;

        // Set can navigate back
        CanNavigateBack = true;

        Navigate(message);
    }

    private void Navigate(NavigateMessage message)
    {
        // Dispose current pages viewmodel
        if (CurrentPage.DataContext is IDisposable viewModel)
        {
            CurrentPage.DataContext = null;
            viewModel.Dispose();
        }

        // Create new page
        switch (message.type.Name)
        {
            case nameof(AutomaticModePage):
                var automaticModeViewModel = (AutomaticModePageVM)ActivatorUtilities.CreateInstance(App.AppHost!.Services, typeof(AutomaticModePageVM), message.VariableName); //App.AppHost!.Services.GetRequiredService<AutomaticModePageVM>();
                AutomaticModePage automaticModePage = new() { DataContext = automaticModeViewModel };
                CurrentPage = automaticModePage;
                Breadcrumb = "> Automatic";
                break;

            case nameof(BatteryOverviewPage):
                var batteryOverviewPageVM = App.AppHost!.Services.GetRequiredService<BatteryOverviewPageVM>();
                BatteryOverviewPage batteryOverviewPage = new() { DataContext = batteryOverviewPageVM };
                CurrentPage = batteryOverviewPage;
                Breadcrumb = "> Manual";
                break;

            case nameof(StringOverviewPage):
                var stringOverviewVM = (StringOverviewPageVM)ActivatorUtilities.CreateInstance(App.AppHost!.Services, typeof(StringOverviewPageVM), message.VariableName);
                StringOverviewPage stringPage = new() { DataContext = stringOverviewVM };
                CurrentPage = stringPage;
                if (message.Header.Length > 0)
                    AppendBreadcrumb(message.Header);
                break;

            case nameof(ModuleOverviewPage):
                var moduleOverviewVM = (ModuleOverviewPageVM)ActivatorUtilities.CreateInstance(App.AppHost!.Services, typeof(ModuleOverviewPageVM), message.VariableName);
                ModuleOverviewPage modulePage = new() { DataContext = moduleOverviewVM };
                CurrentPage = modulePage;
                if (message.Header.Length > 0)
                    AppendBreadcrumb(message.Header);
                break;

            case nameof(UnitOverviewPage):
                var unitOverviewVM = (UnitOverviewPageVM)ActivatorUtilities.CreateInstance(App.AppHost!.Services, typeof(UnitOverviewPageVM), message.VariableName);
                unitOverviewVM.UnitName = message.Header;
                UnitOverviewPage unitPage = new() { DataContext = unitOverviewVM };
                CurrentPage = unitPage;
                if (message.Header.Length > 0)
                    AppendBreadcrumb(message.Header);
                break;

            case nameof(EventsPage):
#pragma warning disable MVVMTK0034 // Direct field reference to [ObservableProperty] backing field
                EventsPage eventsPage = new() { DataContext = _eventsPageVM };
#pragma warning restore MVVMTK0034 // Direct field reference to [ObservableProperty] backing field
                CurrentPage = eventsPage;
                Breadcrumb = " > Events";
                break;

            case nameof(SettingsPage):
                // Create seetings page view model only once
                if (_settingsPageVM == null)
                    _settingsPageVM = new(_adsManager, "GVL_CONFIG.stUnitConfig");
                    
                SettingsPage settingsPage = new() { DataContext = _settingsPageVM };
                CurrentPage = settingsPage;
                Breadcrumb = " > Settings";
                break;

            case nameof(KukaRobotPage):
                // Create page view model only once
                if (_kukaRobotPageVM == null)
                    _kukaRobotPageVM = new(_adsManager, "GVL_CONFIG.stRobotConfig");

                KukaRobotPage kukaRobotPage = new() { DataContext = _kukaRobotPageVM };
                CurrentPage = kukaRobotPage;
                Breadcrumb = " > Kuka Roboter";
                break;

            case nameof(HotCoolPlatePage):
                if (_hotCoolplatePageVM == null)
                    _hotCoolplatePageVM = new(_adsManager, "GVL_Config.stHotCoolplateConfig");

                HotCoolPlatePage hotCoolPlatePage = new() {DataContext = _hotCoolplatePageVM };
                CurrentPage = hotCoolPlatePage;
                Breadcrumb = " > Heiz- /Kühlplatte";
                break;


            case nameof(ChuckMagazinPage):
                if (_chuckMagazinPageVM == null)
                    _chuckMagazinPageVM = new(_adsManager, "GVL_Config.stChuckMagazinConfig");

                ChuckMagazinPage chuckMagazinPage = new() { DataContext= _chuckMagazinPageVM };
                CurrentPage = chuckMagazinPage;
                Breadcrumb = " > Tellermagazin";
                break;

            default:
                CurrentPage = new Page();
                break;
        }
    }

    private void AppendBreadcrumb(string path)
    {
        if (Breadcrumb[^1] != ' ')
            Breadcrumb += " > " + path;
        else
            Breadcrumb += "> " + path;
    }

    [RelayCommand]
    private void AckAlarms()
    {
        _adsManager.WriteValue("GVL_SCADA.stAckAlarmsButton.xRequest", true);
    }

    public void Dispose()
    {
        // Dispose current pages viewmodel
        if (CurrentPage.DataContext is IDisposable viewModel)
        {
            CurrentPage.DataContext = null;
            viewModel.Dispose();
        }

        DummyStringVM.Dispose();
    }
}