using Microsoft.AspNetCore.SignalR.Client;

namespace RobotNet10.Components.Clients;

public abstract class HubClient
{
    public event Func<HubConnectionState, Task>? ConnectionStateChanged;
    public bool IsConnected => Connection.State == HubConnectionState.Connected;
    protected HubConnection Connection { get; }
    private readonly ManualResetEvent connectedWaitHandler = new(false);

    protected HubClient(Uri url)
    {
        Connection = new HubConnectionBuilder()
                            .WithUrl(url)
                            .WithAutomaticReconnect(new HubClientRepeatRetryPolicy(TimeSpan.FromSeconds(3)))
                            .Build();

        Connection.Closed += Connection_Closed;
        Connection.Reconnected += Connection_Reconnected;
    }

    private Task Connection_Closed(Exception? arg)
    {
        return ConnectionStateChanged?.Invoke(Connection.State) ?? Task.CompletedTask;
    }

    private Task Connection_Reconnected(string? arg)
    {
        return ConnectionStateChanged?.Invoke(Connection.State) ?? Task.CompletedTask;
    }


    public virtual async Task StartAsync()
    {
        if (Connection.State == HubConnectionState.Disconnected)
        {
            await Connection.StartAsync();
            ConnectionStateChanged?.Invoke(Connection.State);
            connectedWaitHandler.Set();
        }
    }

    public void WaitForConnected() => connectedWaitHandler.WaitOne();

    public virtual async Task StopAsync()
    {
        if (Connection.State != HubConnectionState.Disconnected)
        {
            await Connection.StopAsync();
            ConnectionStateChanged?.Invoke(Connection.State);
        }
    }

    public class HubClientRepeatRetryPolicy(TimeSpan repeatSpan) : IRetryPolicy
    {
        private readonly TimeSpan RepeatTimeSpan = repeatSpan;

        public TimeSpan? NextRetryDelay(RetryContext retryContext) => RepeatTimeSpan;
    }

}