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
{
    public class AddressSpaceDiffTests
    {
        private static GalaxyObjectInfo Obj(int id, string tag, int parent = 0, bool isArea = false)
            => new GalaxyObjectInfo { GobjectId = id, TagName = tag, BrowseName = tag, ContainedName = tag, ParentGobjectId = parent, IsArea = isArea };

        private static GalaxyAttributeInfo Attr(int gobjectId, string name, string tagName = "Obj", int mxDataType = 5)
            => new GalaxyAttributeInfo { GobjectId = gobjectId, AttributeName = name, FullTagReference = $"{tagName}.{name}", MxDataType = mxDataType, TagName = tagName };

        [Fact]
        public void NoChanges_ReturnsEmptySet()
        {
            var h = new List<GalaxyObjectInfo> { Obj(1, "A") };
            var a = new List<GalaxyAttributeInfo> { Attr(1, "X") };

            var changed = AddressSpaceDiff.FindChangedGobjectIds(h, a, h, a);
            changed.ShouldBeEmpty();
        }

        [Fact]
        public void AddedObject_Detected()
        {
            var oldH = new List<GalaxyObjectInfo> { Obj(1, "A") };
            var newH = new List<GalaxyObjectInfo> { Obj(1, "A"), Obj(2, "B") };
            var a = new List<GalaxyAttributeInfo>();

            var changed = AddressSpaceDiff.FindChangedGobjectIds(oldH, a, newH, a);
            changed.ShouldContain(2);
            changed.ShouldNotContain(1);
        }

        [Fact]
        public void RemovedObject_Detected()
        {
            var oldH = new List<GalaxyObjectInfo> { Obj(1, "A"), Obj(2, "B") };
            var newH = new List<GalaxyObjectInfo> { Obj(1, "A") };
            var a = new List<GalaxyAttributeInfo>();

            var changed = AddressSpaceDiff.FindChangedGobjectIds(oldH, a, newH, a);
            changed.ShouldContain(2);
            changed.ShouldNotContain(1);
        }

        [Fact]
        public void ModifiedObject_BrowseNameChange_Detected()
        {
            var oldH = new List<GalaxyObjectInfo> { Obj(1, "A") };
            var newH = new List<GalaxyObjectInfo> { new GalaxyObjectInfo { GobjectId = 1, TagName = "A", BrowseName = "A_Renamed", ContainedName = "A" } };
            var a = new List<GalaxyAttributeInfo>();

            var changed = AddressSpaceDiff.FindChangedGobjectIds(oldH, a, newH, a);
            changed.ShouldContain(1);
        }

        [Fact]
        public void ModifiedObject_ParentChange_Detected()
        {
            var oldH = new List<GalaxyObjectInfo> { Obj(1, "A"), Obj(2, "B", parent: 1) };
            var newH = new List<GalaxyObjectInfo> { Obj(1, "A"), new GalaxyObjectInfo { GobjectId = 2, TagName = "B", BrowseName = "B", ContainedName = "B", ParentGobjectId = 0 } };
            var a = new List<GalaxyAttributeInfo>();

            var changed = AddressSpaceDiff.FindChangedGobjectIds(oldH, a, newH, a);
            changed.ShouldContain(2);
        }

        [Fact]
        public void AttributeAdded_Detected()
        {
            var h = new List<GalaxyObjectInfo> { Obj(1, "A") };
            var oldA = new List<GalaxyAttributeInfo> { Attr(1, "X") };
            var newA = new List<GalaxyAttributeInfo> { Attr(1, "X"), Attr(1, "Y") };

            var changed = AddressSpaceDiff.FindChangedGobjectIds(h, oldA, h, newA);
            changed.ShouldContain(1);
        }

        [Fact]
        public void AttributeRemoved_Detected()
        {
            var h = new List<GalaxyObjectInfo> { Obj(1, "A") };
            var oldA = new List<GalaxyAttributeInfo> { Attr(1, "X"), Attr(1, "Y") };
            var newA = new List<GalaxyAttributeInfo> { Attr(1, "X") };

            var changed = AddressSpaceDiff.FindChangedGobjectIds(h, oldA, h, newA);
            changed.ShouldContain(1);
        }

        [Fact]
        public void AttributeFieldChange_Detected()
        {
            var h = new List<GalaxyObjectInfo> { Obj(1, "A") };
            var oldA = new List<GalaxyAttributeInfo> { Attr(1, "X", mxDataType: 5) };
            var newA = new List<GalaxyAttributeInfo> { Attr(1, "X", mxDataType: 2) };

            var changed = AddressSpaceDiff.FindChangedGobjectIds(h, oldA, h, newA);
            changed.ShouldContain(1);
        }

        [Fact]
        public void AttributeSecurityChange_Detected()
        {
            var h = new List<GalaxyObjectInfo> { Obj(1, "A") };
            var oldA = new List<GalaxyAttributeInfo> { new GalaxyAttributeInfo { GobjectId = 1, AttributeName = "X", FullTagReference = "A.X", SecurityClassification = 1 } };
            var newA = new List<GalaxyAttributeInfo> { new GalaxyAttributeInfo { GobjectId = 1, AttributeName = "X", FullTagReference = "A.X", SecurityClassification = 2 } };

            var changed = AddressSpaceDiff.FindChangedGobjectIds(h, oldA, h, newA);
            changed.ShouldContain(1);
        }

        [Fact]
        public void ExpandToSubtrees_IncludesChildren()
        {
            var h = new List<GalaxyObjectInfo>
            {
                Obj(1, "Root"),
                Obj(2, "Child", parent: 1),
                Obj(3, "Grandchild", parent: 2),
                Obj(4, "Sibling", parent: 1),
                Obj(5, "Unrelated")
            };

            var changed = new HashSet<int> { 1 };
            var expanded = AddressSpaceDiff.ExpandToSubtrees(changed, h);

            expanded.ShouldContain(1);
            expanded.ShouldContain(2);
            expanded.ShouldContain(3);
            expanded.ShouldContain(4);
            expanded.ShouldNotContain(5);
        }

        [Fact]
        public void ExpandToSubtrees_LeafNode_NoExpansion()
        {
            var h = new List<GalaxyObjectInfo>
            {
                Obj(1, "Root"),
                Obj(2, "Child", parent: 1),
                Obj(3, "Sibling", parent: 1)
            };

            var changed = new HashSet<int> { 2 };
            var expanded = AddressSpaceDiff.ExpandToSubtrees(changed, h);

            expanded.ShouldContain(2);
            expanded.ShouldNotContain(1);
            expanded.ShouldNotContain(3);
        }
    }
}