// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using System;
 
namespace Microsoft.AspNetCore.SignalR.Client;
 
/// <summary>
/// An abstraction that controls when the client attempts to reconnect and how many times it does so.
/// </summary>
public interface IRetryPolicy
{
    /// <summary>
    /// If passed to <see cref="HubConnectionBuilderExtensions.WithAutomaticReconnect(IHubConnectionBuilder, IRetryPolicy)"/>,
    /// this will be called after the transport loses a connection to determine if and for how long to wait before the next reconnect attempt.
    /// </summary>
    /// <param name="retryContext">
    /// Information related to the next possible reconnect attempt including the number of consecutive failed retries so far, time spent
    /// reconnecting so far and the error that lead to this reconnect attempt.
    /// </param>
    /// <returns>
    /// A <see cref="TimeSpan"/> representing the amount of time to wait from now before starting the next reconnect attempt.
    /// <see langword="null" /> tells the client to stop retrying and close.
    /// </returns>
    TimeSpan? NextRetryDelay(RetryContext retryContext);
}