RobotApp/RobotApp.Client/Services/RobotMonitorService.cs

using Microsoft.AspNetCore.Components;
using Microsoft.AspNetCore.SignalR.Client;
using RobotApp.Common.Shares.Dtos;

namespace RobotApp.Client.Services;

public class RobotMonitorService : IAsyncDisposable
{
    private HubConnection? _hubConnection;
    private readonly string _hubUrl;

    public event Action<RobotMonitorDto>? OnDataReceived;
    public bool IsConnected => _hubConnection?.State == HubConnectionState.Connected;

    public RobotMonitorService(NavigationManager navigationManager)
    {
        var baseUrl = navigationManager.BaseUri.TrimEnd('/');
        _hubUrl = $"{baseUrl}/hubs/robotMonitor";
    }

    public async Task StartAsync()
    {
        if (_hubConnection is not null) return;

        _hubConnection = new HubConnectionBuilder()
            .WithUrl(_hubUrl)
            .WithAutomaticReconnect()
            .Build();

        _hubConnection.On<RobotMonitorDto>("ReceiveRobotMonitorData", data =>
        {
            OnDataReceived?.Invoke(data);
        });

        await _hubConnection.StartAsync();
    }

    public async Task StopAsync()
    {
        if (_hubConnection is null) return;

        await _hubConnection.StopAsync();
        await _hubConnection.DisposeAsync();
        _hubConnection = null;
    }

    public async ValueTask DisposeAsync()
    {
        await StopAsync();
    }
}