Nebula-Auth/NebulaAuth/ViewModel/MainVM_Proxy.cs

using CommunityToolkit.Mvvm.ComponentModel;
using CommunityToolkit.Mvvm.Input;
using NebulaAuth.Core;
using NebulaAuth.Model;
using NebulaAuth.Model.Entities;
using System.Collections.ObjectModel;
using System.Linq;
using System.Threading.Tasks;
using NebulaAuth.Model.Comparers;

namespace NebulaAuth.ViewModel;

public partial class MainVM
{
    public ObservableCollection<MaProxy> Proxies { get; }

    public MaProxy? SelectedProxy
    {
        get => _selectedProxy;
        set
        {
            if (SetProperty(ref _selectedProxy, value))
            {
                OnPropertyChanged(nameof(IsDefaultProxy));
                OnProxyChanged();
            };
        }

    }
    private MaProxy? _selectedProxy;

    [ObservableProperty] private bool _proxyExist = true;
    public bool IsDefaultProxy => SelectedProxy == null && MaClient.DefaultProxy != null;
    private bool _handleProxyChange;

    private void SetCurrentProxy()
    {
        if (ReferenceEquals(_selectedProxy, SelectedMafile?.Proxy) == false && _selectedProxy?.Equals(SelectedMafile?.Proxy) == false)
            _handleProxyChange = true;

        if (SelectedMafile == null)
        {
            SelectedProxy = null;
            return;
        }
        if (SelectedMafile.Proxy == null)
        {
            SelectedProxy = SelectedMafile.Proxy;
        }
        else
        {
            var existed = Proxies.FirstOrDefault(p => p.Id == SelectedMafile.Proxy.Id);


            if (existed == null || ProxyDataComparer.Equal(existed.Data, SelectedMafile.Proxy.Data) == false)
            {
                SelectedProxy = SelectedMafile.Proxy;
            }
            else
            {
                SelectedProxy = existed;
            }
        }

        CheckProxyExist();

    }

    private void CheckProxyExist()
    {
        if (SelectedProxy == null)
        {
            ProxyExist = true;
            return;
        }

        var selectedId = SelectedProxy.Id;
        ProxyExist = ProxyStorage.Proxies.TryGetValue(selectedId, out var existedProxy)
                     && SelectedProxy.Data.Equals(existedProxy); //Id is not important in 'Equals()' as we extract it from the dictionary
    }

    [RelayCommand]
    private async Task OpenProxyManager()
    {
        await DialogsController.ShowProxyManager(SelectedProxy);
        var oldSelection = SelectedProxy;
        Proxies.Clear();
        foreach (var kvp in ProxyStorage.Proxies)
        {
            Proxies.Add(new MaProxy(kvp.Key, kvp.Value));
        }
        SelectedProxy = oldSelection;
        SetCurrentProxy();
        OnPropertyChanged(nameof(IsDefaultProxy));
        _handleProxyChange = false;
    }

    [RelayCommand]
    private void RemoveProxy()
    {
        if (SelectedProxy == null) return;
        if (SelectedMafile == null) return;
        if (!ValidateCanSaveAndWarn(SelectedMafile)) return;
        SelectedMafile.Proxy = null;
        SelectedProxy = null;
        Storage.UpdateMafile(SelectedMafile);
        ProxyExist = true;
    }

    private void OnProxyChanged()
    {
        if (_handleProxyChange)
        {
            _handleProxyChange = false;
            return;
        }

        if (SelectedMafile == null) return;
        if (!ValidateCanSaveAndWarn(SelectedMafile)) return;
        ProxyExist = true;
        SelectedMafile.Proxy = SelectedProxy;
        Storage.UpdateMafile(SelectedMafile);
    }

    private bool ValidateCanSaveAndWarn(Mafile data)
    {
        var canSave = Storage.ValidateCanSave(data);
        if (!canSave)
        {
            SnackbarController.SendSnackbar(GetLocalizationOrDefault("CantRetrieveSteamIDToUpdate"));
        }
        return canSave;
    }
}