using System.Collections.Generic;
using Shouldly;
using Xunit;
using ZB.MOM.WW.LmxOpcUa.Host.Domain;
using ZB.MOM.WW.LmxOpcUa.Host.OpcUa;

namespace ZB.MOM.WW.LmxOpcUa.Tests.OpcUa
{
    /// <summary>
    /// Verifies rebuild behavior by comparing address-space models before and after metadata changes.
    /// </summary>
    public class LmxNodeManagerRebuildTests
    {
        /// <summary>
        /// Confirms that rebuilding with new metadata replaces the old tag-reference set.
        /// </summary>
        [Fact]
        public void Rebuild_NewBuild_ReplacesOldData()
        {
            var hierarchy1 = new List<GalaxyObjectInfo>
            {
                new GalaxyObjectInfo { GobjectId = 1, TagName = "OldObj", BrowseName = "OldObj", ParentGobjectId = 0, IsArea = false }
            };
            var attrs1 = new List<GalaxyAttributeInfo>
            {
                new GalaxyAttributeInfo { GobjectId = 1, TagName = "OldObj", AttributeName = "OldAttr", FullTagReference = "OldObj.OldAttr", MxDataType = 5, IsArray = false }
            };

            var model1 = AddressSpaceBuilder.Build(hierarchy1, attrs1);
            model1.NodeIdToTagReference.ContainsKey("OldObj.OldAttr").ShouldBe(true);

            // Rebuild with new data
            var hierarchy2 = new List<GalaxyObjectInfo>
            {
                new GalaxyObjectInfo { GobjectId = 2, TagName = "NewObj", BrowseName = "NewObj", ParentGobjectId = 0, IsArea = false }
            };
            var attrs2 = new List<GalaxyAttributeInfo>
            {
                new GalaxyAttributeInfo { GobjectId = 2, TagName = "NewObj", AttributeName = "NewAttr", FullTagReference = "NewObj.NewAttr", MxDataType = 2, IsArray = false }
            };

            var model2 = AddressSpaceBuilder.Build(hierarchy2, attrs2);

            // Old nodes not in new model, new nodes present
            model2.NodeIdToTagReference.ContainsKey("OldObj.OldAttr").ShouldBe(false);
            model2.NodeIdToTagReference.ContainsKey("NewObj.NewAttr").ShouldBe(true);
        }

        /// <summary>
        /// Confirms that object counts are recalculated from the latest rebuild input.
        /// </summary>
        [Fact]
        public void Rebuild_UpdatesNodeCounts()
        {
            var hierarchy1 = new List<GalaxyObjectInfo>
            {
                new GalaxyObjectInfo { GobjectId = 1, TagName = "Obj1", BrowseName = "Obj1", ParentGobjectId = 0, IsArea = false },
                new GalaxyObjectInfo { GobjectId = 2, TagName = "Obj2", BrowseName = "Obj2", ParentGobjectId = 0, IsArea = false }
            };
            var model1 = AddressSpaceBuilder.Build(hierarchy1, new List<GalaxyAttributeInfo>());
            model1.ObjectCount.ShouldBe(2);

            var hierarchy2 = new List<GalaxyObjectInfo>
            {
                new GalaxyObjectInfo { GobjectId = 3, TagName = "Obj3", BrowseName = "Obj3", ParentGobjectId = 0, IsArea = false }
            };
            var model2 = AddressSpaceBuilder.Build(hierarchy2, new List<GalaxyAttributeInfo>());
            model2.ObjectCount.ShouldBe(1);
        }

        /// <summary>
        /// Confirms that empty metadata produces an empty address-space model.
        /// </summary>
        [Fact]
        public void EmptyHierarchy_ProducesEmptyModel()
        {
            var model = AddressSpaceBuilder.Build(new List<GalaxyObjectInfo>(), new List<GalaxyAttributeInfo>());
            model.RootNodes.ShouldBeEmpty();
            model.NodeIdToTagReference.ShouldBeEmpty();
            model.ObjectCount.ShouldBe(0);
            model.VariableCount.ShouldBe(0);
        }
    }
}