// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using Microsoft.Extensions.Time.Testing;
 
namespace Aspire.Hosting.Tests.Utils;
 
internal sealed class SignalingFakeTimeProvider(TimeSpan signaledDueTime) : FakeTimeProvider
{
    private readonly TaskCompletionSource _timerCreated = new(TaskCreationOptions.RunContinuationsAsynchronously);
 
    public Task TimerCreated => _timerCreated.Task;
 
    public override ITimer CreateTimer(TimerCallback callback, object? state, TimeSpan dueTime, TimeSpan period)
    {
        var timer = base.CreateTimer(callback, state, dueTime, period);
        // Polly's pooled timeout timers start disabled and are armed through Change,
        // so they cannot match the finite initial due time used for a retry-delay signal.
        // https://github.com/App-vNext/Polly/blob/8.7.0/src/Polly.Core/Utils/CancellationTokenSourcePool.Pooled.cs
        if (dueTime == signaledDueTime)
        {
            // Signal after registration so advancing time cannot race with scheduling the delay.
            _timerCreated.TrySetResult();
        }
 
        return timer;
    }
}