using Shouldly;
using Xunit;
using ZB.MOM.WW.OtOpcUa.Core.Abstractions;

namespace ZB.MOM.WW.OtOpcUa.Core.Abstractions.Tests;

/// <summary>Contract tests for the batched data-change payload types.</summary>
[Trait("Category", "Unit")]
public sealed class DataChangeBatchContractTests
{
    private sealed record FakeHandle(string DiagnosticId) : ISubscriptionHandle;

    /// <summary>Verifies the batch payload carries the subscription handle and its per-tag items.</summary>
    [Fact]
    public void Batch_args_carry_handle_and_items()
    {
        var handle = new FakeHandle("h1");
        var snap = new DataValueSnapshot(42, 0u, DateTime.UtcNow, DateTime.UtcNow);

        var args = new DataChangeBatchEventArgs(handle, new[] { new DataChangeItem("plc/tag1", snap) });

        args.SubscriptionHandle.ShouldBe(handle);
        args.Items.Count.ShouldBe(1);
        args.Items[0].FullReference.ShouldBe("plc/tag1");
        args.Items[0].Snapshot.ShouldBe(snap);
    }
}