using Shouldly;
using Xunit;

namespace ZB.MOM.WW.OtOpcUa.Driver.TwinCAT.Tests;

/// <summary>
///     #630 (same pattern) — <c>InitializeAsync</c> on a live driver overwrote <c>_devices[host]</c> and
///     orphaned the previous state's probe loop + client. It now releases them first.
/// </summary>
[Trait("Category", "Unit")]
public sealed class TwinCATReinitializeReleasesStateTests
{
    /// <summary>Initialize twice: the first state's probe loop has finished and its client is disposed.</summary>
    [Fact]
    public async Task SecondInitialize_StopsFirstStatesLoop_AndDisposesItsClient()
    {
        const string host = "ads://5.23.91.23.1.1:851";
        var factory = new FakeTwinCATClientFactory();
        var drv = new TwinCATDriver(new TwinCATDriverOptions
        {
            Devices = [new TwinCATDeviceOptions(host)],
            Probe = new TwinCATProbeOptions { Enabled = true, Interval = TimeSpan.FromMilliseconds(20), Timeout = TimeSpan.FromSeconds(1) },
        }, "drv-reinit", factory);
        await drv.InitializeAsync("{}", CancellationToken.None);

        var first = drv.GetDeviceState(host)!;
        // Positive control: the first probe loop is running and holds a connected client.
        var deadline = DateTime.UtcNow.AddSeconds(5);
        while (!(factory.Clients.Count > 0 && factory.Clients[0].IsConnected))
        {
            if (DateTime.UtcNow > deadline) throw new TimeoutException("probe never connected");
            await Task.Delay(10);
        }
        var firstClient = factory.Clients[0];
        var firstLoop = first.ProbeTask;
        firstLoop.ShouldNotBeNull();
        firstLoop!.IsCompleted.ShouldBeFalse();

        await drv.InitializeAsync("{}", CancellationToken.None);

        firstLoop.IsCompleted.ShouldBeTrue(); // joined
        firstClient.DisposeCount.ShouldBeGreaterThanOrEqualTo(1);
        firstClient.IsConnected.ShouldBeFalse();
        drv.GetDeviceState(host).ShouldNotBeSameAs(first);

        await drv.ShutdownAsync(CancellationToken.None);
    }
}