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

namespace ZB.MOM.WW.LmxOpcUa.Tests.Wiring
{
    /// <summary>
    /// Verifies: Galaxy change detection → OnGalaxyChanged → address space rebuild
    /// </summary>
    public class ChangeDetectionToRebuildWiringTest
    {
        /// <summary>
        /// Confirms that a changed deploy timestamp causes the change-detection pipeline to raise another rebuild signal.
        /// </summary>
        [Fact]
        public async Task ChangedTimestamp_TriggersRebuild()
        {
            var repo = new FakeGalaxyRepository
            {
                LastDeployTime = new DateTime(2024, 1, 1),
                Hierarchy = new List<GalaxyObjectInfo>
                {
                    new GalaxyObjectInfo { GobjectId = 1, TagName = "Obj1", BrowseName = "Obj1", ParentGobjectId = 0, IsArea = false }
                },
                Attributes = new List<GalaxyAttributeInfo>
                {
                    new GalaxyAttributeInfo { GobjectId = 1, TagName = "Obj1", AttributeName = "Attr1", FullTagReference = "Obj1.Attr1", MxDataType = 5, IsArray = false }
                }
            };

            var rebuildCount = 0;
            var service = new ChangeDetectionService(repo, intervalSeconds: 1);
            service.OnGalaxyChanged += () => Interlocked.Increment(ref rebuildCount);

            service.Start();
            await Task.Delay(500); // First poll triggers
            rebuildCount.ShouldBeGreaterThanOrEqualTo(1);

            // Change deploy time → should trigger rebuild
            repo.LastDeployTime = new DateTime(2024, 2, 1);
            await Task.Delay(1500);
            service.Stop();

            rebuildCount.ShouldBeGreaterThanOrEqualTo(2);
            service.Dispose();
        }
    }
}