using NUnit.Framework;
using UnityEngine;
using Newtonsoft.Json.Linq;
using MCPForUnity.Editor.Tools;

namespace MCPForUnityTests.Editor.Tools
{
    public class ManageSceneHierarchyPagingTests
    {
        private GameObject _root;
        private readonly System.Collections.Generic.List<GameObject> _created = new System.Collections.Generic.List<GameObject>();

        [TearDown]
        public void TearDown()
        {
            for (int i = 0; i < _created.Count; i++)
            {
                if (_created[i] != null) Object.DestroyImmediate(_created[i]);
            }
            _created.Clear();

            if (_root != null)
            {
                Object.DestroyImmediate(_root);
                _root = null;
            }
        }

        [Test]
        public void GetHierarchy_PaginatesRoots_AndSupportsChildrenPaging()
        {
            // Arrange: create many roots so paging must occur.
            // Note: Keep counts modest to avoid slowing EditMode tests.
            const int rootCount = 40;
            for (int i = 0; i < rootCount; i++)
            {
                _created.Add(new GameObject($"HS_Root_{i:D2}"));
            }

            _root = new GameObject("HS_Parent");
            for (int i = 0; i < 15; i++)
            {
                var child = new GameObject($"HS_Child_{i:D2}");
                child.transform.SetParent(_root.transform);
            }

            // Act: request a small page to force truncation
            var p1 = new JObject
            {
                ["action"] = "get_hierarchy",
                ["pageSize"] = 10,
            };
            var raw1 = ManageScene.HandleCommand(p1);
            var res1 = raw1 as JObject ?? JObject.FromObject(raw1);

            // Assert: envelope success + payload shape
            Assert.IsTrue(res1.Value<bool>("success"), res1.ToString());
            var data1 = res1["data"] as JObject;
            Assert.IsNotNull(data1, "Expected data payload to be an object.");
            Assert.AreEqual("roots", data1.Value<string>("scope"));
            Assert.AreEqual(true, data1.Value<bool>("truncated"), "Expected truncation when pageSize < root count.");
            Assert.IsNotNull(data1["next_cursor"], "Expected next_cursor when truncated.");

            var items1 = data1["items"] as JArray;
            Assert.IsNotNull(items1, "Expected items array.");
            Assert.AreEqual(10, items1.Count, "Expected exactly pageSize items returned.");

            // Act: fetch next page of roots using next_cursor
            var cursor = data1.Value<string>("next_cursor");
            var p2 = new JObject
            {
                ["action"] = "get_hierarchy",
                ["pageSize"] = 10,
                ["cursor"] = cursor,
            };
            var raw2 = ManageScene.HandleCommand(p2);
            var res2 = raw2 as JObject ?? JObject.FromObject(raw2);
            Assert.IsTrue(res2.Value<bool>("success"), res2.ToString());
            var data2 = res2["data"] as JObject;
            Assert.IsNotNull(data2);
            var items2 = data2["items"] as JArray;
            Assert.IsNotNull(items2);
            Assert.AreEqual(10, items2.Count);

            // Act: page children of a specific parent via 'parent' param (instance ID)
            var pChildren = new JObject
            {
                ["action"] = "get_hierarchy",
                ["parent"] = _root.GetInstanceID(),
                ["pageSize"] = 7,
            };
            var rawChildren = ManageScene.HandleCommand(pChildren);
            var resChildren = rawChildren as JObject ?? JObject.FromObject(rawChildren);
            Assert.IsTrue(resChildren.Value<bool>("success"), resChildren.ToString());
            var dataChildren = resChildren["data"] as JObject;
            Assert.IsNotNull(dataChildren);
            Assert.AreEqual("children", dataChildren.Value<string>("scope"));
            Assert.AreEqual(true, dataChildren.Value<bool>("truncated"));
            Assert.IsNotNull(dataChildren["next_cursor"]);
            var childItems = dataChildren["items"] as JArray;
            Assert.IsNotNull(childItems);
            Assert.AreEqual(7, childItems.Count);
        }
    }
}