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

namespace ZB.MOM.WW.LmxOpcUa.Tests.EndToEnd
{
    /// <summary>
    /// THE ULTIMATE SMOKE TEST: Full service with fakes, verifying the complete data flow.
    /// (1) Address space built, (2) MXAccess data change → callback, (3) read → correct tag ref,
    /// (4) write → correct tag+value, (5) dashboard has real data.
    /// </summary>
    public class FullDataFlowTest
    {
        /// <summary>
        /// Confirms that the fake-backed bridge can start, build the address space, and expose coherent status data end to end.
        /// </summary>
        [Fact]
        public void FullDataFlow_EndToEnd()
        {
            var config = new AppConfiguration
            {
                OpcUa = new OpcUaConfiguration { Port = 14842, GalaxyName = "TestGalaxy", EndpointPath = "/LmxOpcUa" },
                MxAccess = new MxAccessConfiguration { ClientName = "Test", ReadTimeoutSeconds = 2, WriteTimeoutSeconds = 2 },
                GalaxyRepository = new GalaxyRepositoryConfiguration { ChangeDetectionIntervalSeconds = 60 },
                Dashboard = new DashboardConfiguration { Enabled = false }
            };

            var proxy = new FakeMxProxy();
            var repo = new FakeGalaxyRepository
            {
                Hierarchy = new List<GalaxyObjectInfo>
                {
                    new GalaxyObjectInfo { GobjectId = 1, TagName = "DEV", BrowseName = "DEV", ParentGobjectId = 0, IsArea = true },
                    new GalaxyObjectInfo { GobjectId = 2, TagName = "TestMachine_001", BrowseName = "TestMachine_001", ParentGobjectId = 1, IsArea = false },
                    new GalaxyObjectInfo { GobjectId = 3, TagName = "DelmiaReceiver_001", ContainedName = "DelmiaReceiver", BrowseName = "DelmiaReceiver", ParentGobjectId = 2, IsArea = false }
                },
                Attributes = new List<GalaxyAttributeInfo>
                {
                    new GalaxyAttributeInfo { GobjectId = 2, TagName = "TestMachine_001", AttributeName = "MachineID", FullTagReference = "TestMachine_001.MachineID", MxDataType = 5, IsArray = false },
                    new GalaxyAttributeInfo { GobjectId = 3, TagName = "DelmiaReceiver_001", AttributeName = "DownloadPath", FullTagReference = "DelmiaReceiver_001.DownloadPath", MxDataType = 5, IsArray = false },
                    new GalaxyAttributeInfo { GobjectId = 3, TagName = "DelmiaReceiver_001", AttributeName = "JobStepNumber", FullTagReference = "DelmiaReceiver_001.JobStepNumber", MxDataType = 2, IsArray = false }
                }
            };

            var service = new OpcUaService(config, proxy, repo);
            service.Start();

            try
            {
                // (1) OPC UA server host created
                service.ServerHost.ShouldNotBeNull();

                // (2) MXAccess connected and proxy registered
                proxy.IsRegistered.ShouldBe(true);
                service.MxClient.ShouldNotBeNull();
                service.MxClient!.State.ShouldBe(ConnectionState.Connected);

                // (3) Address space model can be built from the same data
                var model = Host.OpcUa.AddressSpaceBuilder.Build(repo.Hierarchy, repo.Attributes);
                model.NodeIdToTagReference.ContainsKey("TestMachine_001.MachineID").ShouldBe(true);
                model.NodeIdToTagReference.ContainsKey("DelmiaReceiver_001.DownloadPath").ShouldBe(true);
                model.NodeIdToTagReference.ContainsKey("DelmiaReceiver_001.JobStepNumber").ShouldBe(true);
                model.VariableCount.ShouldBe(3);
                model.ObjectCount.ShouldBe(2); // TestMachine + DelmiaReceiver (DEV is area)

                // (4) Tag reference resolves correctly for read/write
                var tagRef = model.NodeIdToTagReference["DelmiaReceiver_001.DownloadPath"];
                tagRef.ShouldBe("DelmiaReceiver_001.DownloadPath");

                // (5) Galaxy stats have real data
                service.GalaxyStatsInstance.ShouldNotBeNull();
                service.GalaxyStatsInstance!.GalaxyName.ShouldBe("TestGalaxy");
                service.GalaxyStatsInstance.DbConnected.ShouldBe(true);
                service.GalaxyStatsInstance.ObjectCount.ShouldBe(3);
                service.GalaxyStatsInstance.AttributeCount.ShouldBe(3);

                // (5b) Status report has real data
                service.StatusReportInstance.ShouldNotBeNull();
                var html = service.StatusReportInstance!.GenerateHtml();
                html.ShouldContain("TestGalaxy");
                html.ShouldContain("Connected");

                var json = service.StatusReportInstance.GenerateJson();
                json.ShouldContain("TestGalaxy");

                service.StatusReportInstance.IsHealthy().ShouldBe(true);

                // Verify change detection is wired
                service.ChangeDetectionInstance.ShouldNotBeNull();

                // Verify metrics created
                service.Metrics.ShouldNotBeNull();
            }
            finally
            {
                service.Stop();
            }
        }
    }
}