using System.Threading.Tasks;
using Shouldly;
using Xunit;
using ZB.MOM.WW.LmxOpcUa.Host.Domain;
using ZB.MOM.WW.LmxOpcUa.Host.OpcUa;
using ZB.MOM.WW.LmxOpcUa.Tests.Helpers;

namespace ZB.MOM.WW.LmxOpcUa.Tests.Wiring
{
    /// <summary>
    /// Verifies: FakeMxProxy OnDataChange → MxAccessClient → OnTagValueChanged → node manager delivery
    /// </summary>
    public class MxAccessToNodeManagerWiringTest
    {
        /// <summary>
        /// Confirms that a simulated data change reaches the global tag-value-changed event.
        /// </summary>
        [Fact]
        public async Task DataChange_ReachesGlobalHandler()
        {
            var mxClient = new FakeMxAccessClient();
            string? receivedAddress = null;
            Vtq? receivedVtq = null;

            mxClient.OnTagValueChanged += (addr, vtq) =>
            {
                receivedAddress = addr;
                receivedVtq = vtq;
            };

            mxClient.SimulateDataChange("TestTag.Attr", Vtq.Good(42));

            receivedAddress.ShouldBe("TestTag.Attr");
            receivedVtq.ShouldNotBeNull();
            receivedVtq.Value.Value.ShouldBe(42);
            receivedVtq.Value.Quality.ShouldBe(Quality.Good);
        }

        /// <summary>
        /// Confirms that a simulated data change reaches the stored per-tag subscription callback.
        /// </summary>
        [Fact]
        public async Task DataChange_ReachesSubscriptionCallback()
        {
            var mxClient = new FakeMxAccessClient();
            Vtq? received = null;

            await mxClient.SubscribeAsync("TestTag.Attr", (addr, vtq) => received = vtq);
            mxClient.SimulateDataChange("TestTag.Attr", Vtq.Good(99));

            received.ShouldNotBeNull();
            received.Value.Value.ShouldBe(99);
        }
    }
}