using System;
using System.Collections;
using TMPro;
using UnityEngine;
using UnityEngine.SceneManagement;
using UnityEngine.UI;

namespace SceneView
{
    public class TreeViewNode : MonoBehaviour
    {
        public TreeViewNode? parent;

        public RectTransform? rectTransform;
        public TextMeshProUGUI? text;
        public Button? label;
        public GameObject? child;
        public RectTransform? childRectTransform;
        public VerticalLayoutGroup? verticalLayout;
        public Button? objectEnable;
        public TextMeshProUGUI? objectText;

        public float buttonHeight = 50;

        private string originalText = "";
        private GameObject? _targetGameObject; // 保存当前节点代表的GameObject
        private bool _childrenGenerated = false; // 标记子节点和组件是否已经生成
        private int _nodeDepth = 0; // 当前节点的深度

        private void Awake()
        {
            CreateUI();
        }

        [ContextMenu("CreateUI")]
        public void CreateUI()
        {
            // 获取 RectTransform 组件，如果不存在则添加
            if (rectTransform == null)
            {
                rectTransform = GetComponent<RectTransform>();
                if (rectTransform == null) rectTransform = gameObject.AddComponent<RectTransform>();

                if (rectTransform == null)
                {
                    Debug.LogError("Failed to add RectTransform to the GameObject.");
                    return;
                }
            }

            rectTransform.sizeDelta = new Vector2(0, buttonHeight);
            rectTransform.anchorMin = Vector2.up;
            rectTransform.anchorMax = Vector2.one;
            rectTransform.pivot = new Vector2(0.5f, 1); // 确保轴心点在顶部中央，便于布局

            var buttonConfig = ButtonConfig.Default;
            buttonConfig.RectConfig.Pivot = new Vector2(0.5f, 1);
            buttonConfig.RectConfig.AnchorMin = new Vector2(0, 1);
            buttonConfig.RectConfig.AnchorMax = new Vector2(1, 1);
            buttonConfig.RectConfig.SizeDelta = new Vector2(0, buttonHeight);
            buttonConfig.BackgroundColor = new Color(0.2f, 0.2f, 0.2f, 1f); // 默认背景色

            // 创建按钮并检查是否已存在
            if (label == null)
            {
                var button = ControlUtilities.CreateButton(rectTransform, buttonConfig, null);
                label = button.button;
                text = button.text;
                if (text == null)
                {
                    Debug.LogError("Failed to get button text.");
                    return;
                }

                text.alignment = TextAlignmentOptions.MidlineLeft;
                text.color = Color.white; // 确保文本颜色可见
            }

            if (objectEnable == null)
            {
                var button = ControlUtilities.CreateButton(rectTransform, buttonConfig, null);
                objectEnable = button.button;
                objectText = button.text;
                objectText.text = ""; // 默认文本为空，使用颜色作指示
                objectText.color = Color.black; // 确保文本颜色可见
                button.button.image.color = Color.yellow; // 默认颜色
                var rect = objectEnable.GetComponent<RectTransform>();
                rect.anchorMin = Vector2.one;
                rect.anchorMax = Vector2.one;
                rect.pivot = new Vector2(1, 1); // 右上角锚点
                rect.sizeDelta = new Vector2(30, 30);
                rect.anchoredPosition = new Vector2(-10, -10); // 距离右上角10像素
            }

            // 检查子对象是否存在
            child = transform.Find("content")?.gameObject;
            if (child == null)
            {
                child = new GameObject("content");
                child.transform.SetParent(rectTransform, false);
                if (child == null)
                {
                    Debug.LogError("Failed to create or set parent for child content.");
                    return;
                }

                childRectTransform = child.AddComponent<RectTransform>();
                if (childRectTransform == null)
                {
                    Debug.LogError("Failed to add RectTransform to the child content.");
                    return;
                }
            }
            else
            {
                childRectTransform = child.GetComponent<RectTransform>();
                if (childRectTransform == null)
                {
                    Debug.LogError("Failed to get RectTransform for the child content.");
                    return;
                }
            }
            
            // 确保子内容一开始是隐藏的 (懒加载的初始状态)
            child.SetActive(false);

            childRectTransform.anchorMin = new Vector2(0, 1);
            childRectTransform.anchorMax = new Vector2(1, 1);
            childRectTransform.pivot = new Vector2(0.5f, 1);
            childRectTransform.offsetMax = new Vector2(0, -buttonHeight); // 占据主按钮以下的空间
            childRectTransform.offsetMin = new Vector2(0, 0); // 确保底部没有额外偏移

            verticalLayout = child.GetComponent<VerticalLayoutGroup>();
            var sizeFitter = child.GetComponent<ContentSizeFitter>();

            if (verticalLayout == null)
            {
                verticalLayout = child.AddComponent<VerticalLayoutGroup>();
                if (verticalLayout == null)
                {
                    Debug.LogError("Failed to add VerticalLayoutGroup to the child content.");
                    return;
                }
            }

            if (sizeFitter == null)
            {
                sizeFitter = child.AddComponent<ContentSizeFitter>();
                if (sizeFitter == null)
                {
                    Debug.LogError("Failed to add ContentSizeFitter to the child content.");
                    return;
                }
            }
            
            // 调整布局组参数，确保正确计算
            verticalLayout.padding.left = (int)(buttonHeight * 0.5f); // 增加左边距以缩进
            verticalLayout.padding.top = 2;
            verticalLayout.padding.bottom = 4;
            verticalLayout.spacing = 2;
            verticalLayout.childControlHeight = false; // 由ContentSizeFitter控制子节点高度
            verticalLayout.childControlWidth = true; // 子节点宽度按父级宽度自适应
            verticalLayout.childForceExpandHeight = false; // 不要强制展开高度
            verticalLayout.childAlignment = TextAnchor.UpperLeft; // 确保子元素从上开始排列

            sizeFitter.verticalFit = ContentSizeFitter.FitMode.PreferredSize;
        }

        // 修改为只初始化当前节点，不立即生成子内容
        public IEnumerator InitializeNode(GameObject? targetObject, int depth = 0)
        {
            _targetGameObject = targetObject;
            _nodeDepth = depth;

            // 清除之前的监听器，避免重复
            label?.onClick.RemoveAllListeners();
            objectEnable?.onClick.RemoveAllListeners();

            if (targetObject == null) // 代表这是场景根节点
            {
                originalText = $"场景 {SceneManager.GetActiveScene().name}";
                if (text) text.text = originalText + " →"; // 默认收拢，显示右箭头
                label?.onClick.AddListener(OnExpand); // 场景节点点击展开自身
                objectEnable?.gameObject.SetActive(false); // 场景节点没有Enable/Disable功能
                yield break; // 场景节点不立即生成根对象，等待点击展开
            }

            // 过滤掉特定Canvas
            if (targetObject == null || targetObject.name == CanvasControl.ViewCanvasName)
            {
                yield break;
            }
            
            originalText = GetIndentedName(targetObject.name, depth);
            if (text != null) text.text = originalText + " →"; // 默认收拢，显示右箭头
            
            // 注册展开事件
            label?.onClick.AddListener(OnExpand);

            // 注册对象启用/禁用事件
            objectEnable?.gameObject.SetActive(true);
            objectEnable?.onClick.AddListener(() => OnObjectEnable(_targetGameObject, objectEnable, objectText));
            UpdateObjButton(_targetGameObject, objectEnable, objectText);

            // 确保子内容一开始是隐藏的
            if (child) child.SetActive(false);
            yield return StartCoroutine(DelayedUpdateHeight()); // 初始化时异步更新高度
        }

        // 修改 OnExpand 方法以实现懒加载
        private void OnExpand()
        {
            if (child == null)
            {
                Debug.LogError("Child content not found.");
                return;
            }
            CanvasControl.FocusGameObject=_targetGameObject;

            // 如果已经生成，直接切换显示状态
            if (_childrenGenerated)
            {
                ToggleExpansionVisuals();
                StartCoroutine(DelayedUpdateHeight()); // 每次展开/收拢后异步更新高度
            }
            else // 如果子内容未生成，则异步生成
            { 
                ToggleExpansionVisuals(); // 生成完成后再切换显示状态 (展开或根据后续逻辑)
                // 在生成子节点之前，确保子内容容器是激活的
                child.SetActive(true); // <--- 新增这行，在生成子节点之前激活容器
                
                StartCoroutine(GenerateChildrenContent(_targetGameObject, _nodeDepth + 1, () =>
                {
                    _childrenGenerated = true;
                    // 注意：ToggleExpansionVisuals 会再次调用 child.SetActive()
                    // 如果是展开状态，它会保持 true。如果是收拢，则设置为 false。
                    StartCoroutine(DelayedUpdateHeight()); // 生成并展开后异步更新高度
                }));
            }
        }


        // 新增方法：生成子内容（组件和子GameObject）
        private IEnumerator GenerateChildrenContent(GameObject? targetObject, int depth, Action? onComplete = null)
        {
            ClearChildNodes(); // 在生成之前清空所有旧的子节点

            if (targetObject == null) // 场景根节点，需要遍历根GameObject
            {
                var rootObjects = SceneManager.GetActiveScene().GetRootGameObjects();
                foreach (var rootObject in rootObjects)
                {
                    if (!rootObject || rootObject.name == CanvasControl.ViewCanvasName) continue;

                    var childNodeGO = new GameObject(rootObject.name);
                    var childNode = childNodeGO.AddComponent<TreeViewNode>();
                    childNode.transform.SetParent(childRectTransform, false);
                    childNode.parent = this;
                    childNode.CreateUI(); // 确保UI元素已创建
                    // yield return StartCoroutine(childNode.InitializeNode(rootObject, depth)); // 浅初始化子节点
                    yield return null; // 每处理一个子节点就yield一次，分散帧压力
                }
                onComplete?.Invoke();
                yield break;
            }

            // 生成当前GameObject的组件按钮  
            var components = targetObject.GetComponents<Behaviour>();
            foreach (var component in components)
            {
                if (childRectTransform == null)
                {
                    Debug.LogError("childRectTransform is null");
                    continue;
                }

                var config = ButtonConfig.Default;
                config.RectConfig.SizeDelta = new Vector2(0, 40);
                config.BackgroundColor = component.enabled ? new Color(0.2f, 0.4f, 0.2f, 1f) : new Color(0.4f, 0.2f, 0.2f, 1f); // 根据组件启用状态设置颜色
                config.Text = GetIndentedName(component.GetType().Name, depth, true); // 组件也需要缩进
                config.TextColor = Color.white;
                var buttonBack = ControlUtilities.CreateButton(childRectTransform, config, null);
                if (buttonBack.button == null)
                {
                    Debug.LogError("buttonBack.button is null");
                    continue;
                }

                var button = buttonBack.button;
                var comp = component;
                button.onClick.AddListener(() => OnButtonClick(button, comp));
                yield return null; // 每创建一个组件按钮就yield一次
            }

            // 遍历目标对象的所有子对象并创建新的TreeViewNode（浅初始化）
            foreach (Transform childTransform in targetObject.transform)
            {
                if (childTransform == null)
                {
                    Debug.LogError("Child transform is null.");
                    continue;
                }

                var childNodeGO = new GameObject(childTransform.gameObject.name);
                var childNode = childNodeGO.AddComponent<TreeViewNode>();
                childNode.transform.SetParent(childRectTransform, false);
                childNode.parent = this;
                childNode.CreateUI(); // 确保UI元素已创建
                // yield return StartCoroutine(childNode.InitializeNode(childTransform.gameObject, depth)); // 浅初始化子节点
                yield return null; // 每处理一个子节点就yield一次
            }

            onComplete?.Invoke();
        }

        private void ToggleExpansionVisuals()
        {
            if (child == null) return;

            // 切换 child 的激活状态
            child.SetActive(!child.activeSelf);

            if (text != null)
            {
                if (child.activeSelf)
                {
                    text.text = originalText + " ↓"; // 下三角符号表示展开
                }
                else
                {
                    text.text = originalText + " →"; // 右三角符号表示收拢
                }
            }
        }

        // 异步更新高度，给布局系统一帧时间来计算
        private IEnumerator DelayedUpdateHeight()
        {
            // 等待一帧，让 LayoutGroup 和 ContentSizeFitter 完成计算
            yield return null; 
            InternalUpdateHeight();
        }

        private void InternalUpdateHeight()
        {
            if (rectTransform == null || child == null || childRectTransform == null)
            {
                return; // Editor退出时可能为null
            }

            float currentChildHeight = 0f;
            if (child.activeSelf && _childrenGenerated)
            {
                // 强制重建 childRectTransform 的布局，以获取准确的 PreferredHeight
                LayoutRebuilder.ForceRebuildLayoutImmediate(childRectTransform);
                currentChildHeight = LayoutUtility.GetPreferredHeight(childRectTransform);
            }
            
            // 设置主RectTransform的高度 = 按钮高度 + 子内容高度
            rectTransform.sizeDelta = new Vector2(rectTransform.sizeDelta.x, buttonHeight + currentChildHeight);
            
            // Debug.Log($"Node: {gameObject.name}, childActive: {child.activeSelf}, childrenGenerated: {_childrenGenerated}, currentChildHeight: {currentChildHeight}, finalNodeHeight: {rectTransform.sizeDelta.y}");

            // 如果有父节点，通知父节点重新计算布局
            if (parent != null)
            {
                // 强制重建父节点的 childRectTransform 的布局
                LayoutRebuilder.ForceRebuildLayoutImmediate(parent.childRectTransform);
                // 递归父节点异步更新高度
                StartCoroutine(parent.DelayedUpdateHeight()); 
            }
        }
        
        // 调整 GetIndentedName 以支持组件类型的缩进
        private string GetIndentedName(string name, int depth, bool isComponent = false)
        {
            var indent = "";
            int baseIndent = depth; // GameObject的深度
            if (isComponent) baseIndent++; // 组件比GameObject多一级缩进

            // 增加额外的左边距，以产生层级感
            for (var i = 0; i < baseIndent; i++)
            {
                indent += " "; 
            }
            return $"{indent}{name}";
        }

        public void ClearChildNodes()
        {
            if (childRectTransform != null)
            {
                // 遍历并销毁所有子对象
                for (int i = childRectTransform.childCount - 1; i >= 0; i--)
                {
                    Destroy(childRectTransform.GetChild(i).gameObject);
                }
            }
        }

        private void OnButtonClick(Button button, Behaviour component)
        {
            if (button == null || component == null) return;

            // 切换组件的启用状态
            var isEnabled = !component.enabled;
            component.enabled = isEnabled;
            // 根据组件的启用状态修改按钮背景颜色
            button.image.color = isEnabled ? new Color(0.2f, 0.4f, 0.2f, 1f) : new Color(0.4f, 0.2f, 0.2f, 1f);
        }

        private void OnObjectEnable(GameObject? gameObject, Button? button, TMP_Text? text)
        {
            if (gameObject == null || button == null || text == null) return;

            Debug.Log($"设置{gameObject.name} active = {!gameObject.activeSelf}");
            gameObject.SetActive(!gameObject.activeSelf);
            UpdateObjButton(gameObject, button, text);
        }

        private void UpdateObjButton(GameObject gameObject, Button button, TMP_Text text)
        {
            if (gameObject.activeSelf)
            {
                button.image.color = Color.green;
                text.text = "√"; 
            }
            else
            {
                button.image.color = Color.red;
                text.text = "×"; 
            }
        }
    }

}