using Shouldly;
using Xunit;
using ZB.MOM.WW.OtOpcUa.Driver.AbLegacy.PlcFamilies;

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

/// <summary>
///     #630 — <c>InitializeAsync</c> on a live driver (<c>DriverInstanceActor.AdoptConfigDuringInit</c> runs
///     it with no teardown first) overwrote <c>_devices[host]</c> and orphaned the previous state's
///     probe loop + runtime. It now releases them first.
/// </summary>
[Trait("Category", "Unit")]
public sealed class AbLegacyReinitializeReleasesStateTests
{
    /// <summary>Initialize twice: the first state's probe loop has stopped and its probe runtime is disposed.</summary>
    [Fact]
    public async Task SecondInitialize_StopsFirstStatesLoop_AndDisposesItsRuntime()
    {
        const string host = "ab://10.0.0.5/1,0";
        var factory = new FakeAbLegacyTagFactory();
        var drv = new AbLegacyDriver(new AbLegacyDriverOptions
        {
            Devices = [new AbLegacyDeviceOptions(host, AbLegacyPlcFamily.Slc500)],
            Probe = new AbLegacyProbeOptions { Enabled = true, Interval = TimeSpan.FromMilliseconds(20), ProbeAddress = "S:0" },
        }, "drv-reinit", factory);
        await drv.InitializeAsync("{}", CancellationToken.None);

        var first = drv.GetDeviceState(host)!;
        // Positive control: the first state's probe loop is running and has created + initialised its runtime.
        var deadline = DateTime.UtcNow.AddSeconds(5);
        while (!(factory.Tags.TryGetValue("S:0", out var t) && t.InitializeCount > 0))
        {
            if (DateTime.UtcNow > deadline) throw new TimeoutException("probe never started");
            await Task.Delay(10);
        }
        var firstTag = factory.Tags["S:0"];
        var firstLoop = first.ProbeTask;
        firstLoop.ShouldNotBeNull();
        firstLoop!.IsCompleted.ShouldBeFalse();
        firstTag.Disposed.ShouldBeFalse();

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

        firstLoop.IsCompleted.ShouldBeTrue(); // joined
        firstTag.Disposed.ShouldBeTrue();
        drv.GetDeviceState(host).ShouldNotBeSameAs(first);

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