using System;
using Prefab;
using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.SceneManagement;
using UnityEngine.UI;
using Utils;

namespace Managers
{
    public class TemporaryAnimationManager : MonoSingleton<TemporaryAnimationManager>
    {
        // 将包装图层改为由代码动态创建和管理
        private GameObject _temporaryAnimationLevel;
        private GameObject _temporaryAnimationUILevel;

        [SerializeField] private TemporaryAnimatorImageUI temporaryAnimatorImageUIPrefab;
        [SerializeField] private TemporaryAnimatorSprite temporaryAnimatorSpritePrefab;
        [SerializeField] private TemporaryAnimatorText temporaryAnimatorTextPrefab;
        [SerializeField] private TemporaryAnimatorText temporaryAnimatorUITextPrefab;
        
        protected override void OnStart()
        {
            SceneManager.sceneLoaded += OnSceneLoaded;
            
            CreateAnimationLayersForCurrentScene(SceneManager.GetActiveScene(), LoadSceneMode.Single);
        }

        private void OnDestroy()
        {
            SceneManager.sceneLoaded -= OnSceneLoaded;
            // 在Manager销毁时，也销毁创建的图层，防止残留
            if (_temporaryAnimationLevel != null)
            {
                Destroy(_temporaryAnimationLevel);
            }
            if (_temporaryAnimationUILevel != null)
            {
                Destroy(_temporaryAnimationUILevel);
            }
        }

        private void OnSceneLoaded(Scene scene, LoadSceneMode mode)
        {
            // 在新场景加载时，重新创建动画图层
            CreateAnimationLayersForCurrentScene(scene, mode);
        }

        /// <summary>
        /// 为当前活动场景创建或重新创建临时动画的父级图层。
        /// </summary>
        /// <param name="scene">当前加载的场景。</param>
        /// <param name="mode">场景加载模式。</param>
        private void CreateAnimationLayersForCurrentScene(Scene scene, LoadSceneMode mode)
        {
            // 销毁旧的图层（如果存在），确保每个场景都有独立的图层
            // 注意：如果TemporaryAnimationManager是DontDestroyOnLoad，
            // 那么旧的图层可能还在，需要显式销毁。
            if (_temporaryAnimationLevel != null)
            {
                Destroy(_temporaryAnimationLevel);
            }
            if (_temporaryAnimationUILevel != null)
            {
                Destroy(_temporaryAnimationUILevel);
            }

            // 创建非UI动画的包装图层
            _temporaryAnimationLevel = new GameObject("TemporaryAnimations");
            // 将其移动到当前加载的场景的根目录，使其成为场景的一部分
            SceneManager.MoveGameObjectToScene(_temporaryAnimationLevel, scene);

            // 1. 获取或创建 Canvas
            var mainCanvas = GetOrCreateMainCanvas();
            // 2. 创建 _temporaryAnimationUILevel GameObject
            _temporaryAnimationUILevel = new GameObject("TemporaryUIAnimations");
            // 3. 将其设置为 Canvas 的子对象
            // SetParent(parentTransform, worldPositionStay: false) 会将子对象的局部位置重置为 (0,0,0)
            // 这对于新的UI元素通常是期望的行为
            _temporaryAnimationUILevel.transform.SetParent(mainCanvas.transform, false);
            // 4. 重置新创建的UI容器的局部变换
            // 确保它相对于父级 Canvas 处于一个干净的初始状态
            _temporaryAnimationUILevel.transform.localPosition = Vector3.zero;
            _temporaryAnimationUILevel.transform.localScale = Vector3.one;
            _temporaryAnimationUILevel.transform.localRotation = Quaternion.identity;
            
        }
        
        /// <summary>
        /// 生成一个非UI文本临时动画。
        /// </summary>
        /// <param name="str">动画的文本内容。</param>
        /// <param name="position">动画在世界坐标系中的初始位置。</param>
        /// <param name="lifeTime">动画的生命周期（秒）。</param>
        /// <param name="fps">动画帧率。</param>
        /// <param name="xShift">X轴位移函数。</param>
        /// <param name="yShift">Y轴位移函数。</param>
        public void GenerateTemporaryAnimation(string str, Vector3 position, float lifeTime = 3, float fps = 3,
            Func<float, float> xShift = null,
            Func<float, float> yShift = null)
        {
            if (!_temporaryAnimationLevel)
            {
                Debug.LogError("TemporaryAnimationLevel is not initialized. Cannot generate non-UI animation.");
                return;
            }

            var textObj = Instantiate(temporaryAnimatorTextPrefab, _temporaryAnimationLevel.transform);
            textObj.transform.position = new Vector3(position.x,position.y);
            textObj.Init(str, fps);
            textObj.SetAnimationFunctions(xShift, yShift);
            textObj.lifeTime = lifeTime;
            textObj.gameObject.SetActive(true);
        }

        /// <summary>
        /// 生成一个非UI文本临时动画，可指定父级Transform。
        /// </summary>
        /// <param name="str">动画的文本内容。</param>
        /// <param name="position">动画在世界坐标系中的初始位置。</param>
        /// <param name="parent">动画的父级Transform。如果为null，则使用默认的非UI动画层。</param>
        /// <param name="lifeTime">动画的生命周期（秒）。</param>
        /// <param name="fps">动画帧率。</param>
        /// <param name="xShift">X轴位移函数。</param>
        /// <param name="yShift">Y轴位移函数。</param>
        public void GenerateTemporaryAnimation(string str, Vector3 position, Transform parent, float lifeTime = 3, float fps = 3,
            Func<float, float> xShift = null,
            Func<float, float> yShift = null)
        {
            Transform actualParent = parent ?? _temporaryAnimationLevel?.transform;

            if (actualParent == null)
            {
                Debug.LogError("TemporaryAnimationLevel or specified parent is not initialized. Cannot generate non-UI animation.");
                return;
            }

            var textObj = Instantiate(temporaryAnimatorTextPrefab, actualParent);
            textObj.transform.position = position; // 外部传入的position应视为世界坐标
            textObj.Init(str, fps);
            textObj.SetAnimationFunctions(xShift, yShift);
            textObj.lifeTime = lifeTime;
            textObj.gameObject.SetActive(true);
        }

        /// <summary>
        /// 生成一个非UI精灵临时动画。
        /// </summary>
        /// <param name="sprites">动画的精灵帧数组。</param>
        /// <param name="position">动画在世界坐标系中的初始位置。</param>
        /// <param name="lifeTime">动画的生命周期（秒）。</param>
        /// <param name="fps">动画帧率。</param>
        /// <param name="xShift">X轴位移函数。</param>
        /// <param name="yShift">Y轴位移函数。</param>
        public void GenerateTemporaryAnimation(Sprite[] sprites, Vector3 position,float lifeTime = 3, float fps = 3, Func<float, float> xShift = null,
            Func<float, float> yShift = null)
        {
            if (!_temporaryAnimationLevel)
            {
                Debug.LogError("TemporaryAnimationLevel is not initialized. Cannot generate non-UI animation.");
                return;
            }

            var obj = Instantiate(temporaryAnimatorSpritePrefab, _temporaryAnimationLevel.transform);
            obj.transform.position = new Vector3(position.x,position.y);
            obj.Init(sprites, fps);
            obj.SetAnimationFunctions(xShift, yShift);
            obj.lifeTime = lifeTime;
            obj.gameObject.SetActive(true);

        }

        /// <summary>
        /// 生成一个非UI精灵临时动画，可指定父级Transform。
        /// </summary>
        /// <param name="sprites">动画的精灵帧数组。</param>
        /// <param name="position">动画在世界坐标系中的初始位置。</param>
        /// <param name="parent">动画的父级Transform。如果为null，则使用默认的非UI动画层。</param>
        /// <param name="lifeTime">动画的生命周期（秒）。</param>
        /// <param name="fps">动画帧率。</param>
        /// <param name="xShift">X轴位移函数。</param>
        /// <param name="yShift">Y轴位移函数。</param>
        public void GenerateTemporaryAnimation(Sprite[] sprites, Vector3 position, Transform parent, float lifeTime = 3, float fps = 3, Func<float, float> xShift = null,
            Func<float, float> yShift = null)
        {
            Transform actualParent = parent ?? _temporaryAnimationLevel?.transform;

            if (actualParent == null)
            {
                Debug.LogError("TemporaryAnimationLevel or specified parent is not initialized. Cannot generate non-UI animation.");
                return;
            }

            var obj = Instantiate(temporaryAnimatorSpritePrefab, actualParent);
            obj.transform.position = position; // 外部传入的position应视为世界坐标
            obj.Init(sprites, fps);
            obj.SetAnimationFunctions(xShift, yShift);
            obj.lifeTime = lifeTime;
            obj.gameObject.SetActive(true);
        }
        
        /// <summary>
        /// 生成一个UI文本临时动画。
        /// 此重载将传入的 <paramref name="position"/> 视为屏幕坐标 (如鼠标位置)，并将其自动转换为Canvas局部坐标。
        /// </summary>
        /// <param name="str">动画的文本内容。</param>
        /// <param name="position">动画在屏幕坐标系中的初始位置（如鼠标位置）。</param>
        /// <param name="lifeTime">动画的生命周期（秒）。</param>
        /// <param name="fps">动画帧率。</param>
        /// <param name="xShift">X轴位移函数。</param>
        /// <param name="yShift">Y轴位移函数。</param>
        public void GenerateTemporaryAnimationUI(string str, Vector2 position,float lifeTime = 3, float fps = 3, Func<float, float> xShift = null,
            Func<float, float> yShift = null)
        {
            if (!_temporaryAnimationUILevel)
            {
                Debug.LogError("TemporaryAnimationUILevel is not initialized. Cannot generate UI animation.");
                return;
            }
            
            var textObj = Instantiate(temporaryAnimatorUITextPrefab, _temporaryAnimationUILevel.transform);
            
            RectTransform canvasRectTransform = _temporaryAnimationUILevel.transform as RectTransform;
            if (canvasRectTransform != null)
            {
                // 获取Canvas组件，特别是RenderMode为ScreenSpaceCamera时需要worldCamera
                Canvas rootCanvas = canvasRectTransform.root.GetComponent<Canvas>();
                Camera eventCamera = null;
                if (rootCanvas.renderMode == RenderMode.ScreenSpaceCamera || rootCanvas.renderMode == RenderMode.WorldSpace)
                {
                    eventCamera = rootCanvas.worldCamera; // 使用Canvas指定的相机
                    if (eventCamera == null) // 如果Canvas没有指定相机，尝试主相机
                    {
                        eventCamera = Camera.main;
                    }
                }

                if (RectTransformUtility.ScreenPointToLocalPointInRectangle(canvasRectTransform, position, eventCamera, out var localPoint))
                {
                    textObj.rectTransform.anchoredPosition = localPoint;
                }
                else
                {
                    textObj.rectTransform.anchoredPosition = position; 
                    Debug.LogWarning("Failed to convert screen point to local point for UI text animation. Using raw position.");
                }
            }
            else
            {
                textObj.rectTransform.anchoredPosition = position;
                Debug.LogWarning("TemporaryAnimationUILevel is not a RectTransform. Unable to convert screen point. Using raw position.");
            }
            
            textObj.Init(str, fps);
            textObj.SetAnimationFunctions(xShift, yShift);
            textObj.lifeTime = lifeTime;
            textObj.gameObject.SetActive(true);

        }

        /// <summary>
        /// 生成一个UI文本临时动画，可指定父级RectTransform。
        /// 此重载将传入的 <paramref name="position"/> 视为相对于父级RectTransform的 anchoredPosition。
        /// </summary>
        /// <param name="str">动画的文本内容。</param>
        /// <param name="position">动画在UI坐标系(RectTransform.anchoredPosition)中的初始位置。</param>
        /// <param name="parent">动画的父级RectTransform。如果为null，则使用默认的UI动画层。</param>
        /// <param name="lifeTime">动画的生命周期（秒）。</param>
        /// <param name="fps">动画帧率。</param>
        /// <param name="xShift">X轴位移函数。</param>
        /// <param name="yShift">Y轴位移函数。</param>
        public void GenerateTemporaryAnimationUI(string str, Vector2 position, RectTransform parent, float lifeTime = 3, float fps = 3, Func<float, float> xShift = null,
            Func<float, float> yShift = null)
        {
            RectTransform actualParent = parent ?? (_temporaryAnimationUILevel?.transform as RectTransform);

            if (actualParent == null)
            {
                Debug.LogError("TemporaryAnimationUILevel or specified parent is not initialized or not a RectTransform. Cannot generate UI animation.");
                return;
            }
            
            var textObj = Instantiate(temporaryAnimatorUITextPrefab);
            textObj.rectTransform.SetParent(actualParent, false); // SetParent with worldPositionStay: false
            textObj.rectTransform.anchoredPosition = position; 
            textObj.Init(str, fps);
            textObj.SetAnimationFunctions(xShift, yShift);
            textObj.lifeTime = lifeTime;
            textObj.gameObject.SetActive(true);
        }
        

        /// <summary>
        /// 生成一个UI精灵临时动画。
        /// 此重载将传入的 <paramref name="position"/> 视为屏幕坐标 (如鼠标位置)，并将其自动转换为Canvas局部坐标。
        /// </summary>
        /// <param name="sprites">动画的精灵帧数组。</param>
        /// <param name="position">动画在屏幕坐标系中的初始位置（如鼠标位置）。</param>
        /// <param name="lifeTime">动画的生命周期（秒）。</param>
        /// <param name="fps">动画帧率。</param>
        /// <param name="xShift">X轴位移函数。</param>
        /// <param name="yShift">Y轴位移函数。</param>
        public void GenerateTemporaryAnimationUI(Sprite[] sprites, Vector2 position,float lifeTime = 3, float fps = 3, Func<float, float> xShift = null,
            Func<float, float> yShift = null)
        {
            if (_temporaryAnimationUILevel == null)
            {
                Debug.LogError("TemporaryAnimationUILevel is not initialized. Cannot generate UI animation.");
                return;
            }

            var obj = Instantiate(temporaryAnimatorImageUIPrefab, _temporaryAnimationUILevel.transform);
            
            RectTransform canvasRectTransform = _temporaryAnimationUILevel.transform as RectTransform;
            if (canvasRectTransform != null)
            {
                // 获取Canvas组件，特别是RenderMode为ScreenSpaceCamera时需要worldCamera
                Canvas rootCanvas = canvasRectTransform.root.GetComponent<Canvas>();
                Camera eventCamera = null;
                if (rootCanvas.renderMode == RenderMode.ScreenSpaceCamera || rootCanvas.renderMode == RenderMode.WorldSpace)
                {
                    eventCamera = rootCanvas.worldCamera; // 使用Canvas指定的相机
                    if (eventCamera == null) // 如果Canvas没有指定相机，尝试主相机
                    {
                        eventCamera = Camera.main;
                    }
                }

                Vector2 localPoint;
                if (RectTransformUtility.ScreenPointToLocalPointInRectangle(canvasRectTransform, position, eventCamera, out localPoint))
                {
                    obj.rectTransform.anchoredPosition = localPoint;
                }
                else
                {
                    obj.rectTransform.anchoredPosition = position;
                    Debug.LogWarning("Failed to convert screen point to local point for UI sprite animation. Using raw position.");
                }
            }
            else
            {
                obj.rectTransform.anchoredPosition = position;
                Debug.LogWarning("TemporaryAnimationUILevel is not a RectTransform. Unable to convert screen point. Using raw position.");
            }
            
            obj.Init(sprites, fps);
            obj.SetAnimationFunctions(xShift, yShift);
            obj.lifeTime = lifeTime;
            obj.gameObject.SetActive(true);

        }

        /// <summary>
        /// 生成一个UI精灵临时动画，可指定父级RectTransform。
        /// 此重载将传入的 <paramref name="position"/> 视为相对于父级RectTransform的 anchoredPosition。
        /// </summary>
        /// <param name="sprites">动画的精灵帧数组。</param>
        /// <param name="position">动画在UI坐标系(RectTransform.anchoredPosition)中的初始位置。</param>
        /// <param name="parent">动画的父级RectTransform。如果为null，则使用默认的UI动画层。</param>
        /// <param name="lifeTime">动画的生命周期（秒）。</param>
        /// <param name="fps">动画帧率。</param>
        /// <param name="xShift">X轴位移函数。</param>
        /// <param name="yShift">Y轴位移函数。</param>
        public void GenerateTemporaryAnimationUI(Sprite[] sprites, Vector2 position, RectTransform parent, float lifeTime = 3, float fps = 3, Func<float, float> xShift = null,
            Func<float, float> yShift = null)
        {
            RectTransform actualParent = parent ?? (_temporaryAnimationUILevel?.transform as RectTransform);

            if (actualParent == null)
            {
                Debug.LogError("TemporaryAnimationUILevel or specified parent is not initialized or not a RectTransform. Cannot generate UI animation.");
                return;
            }

            var obj = Instantiate(temporaryAnimatorImageUIPrefab);
            obj.rectTransform.SetParent(actualParent, false); // SetParent with worldPositionStay: false
            obj.rectTransform.anchoredPosition = position;
            obj.Init(sprites, fps);
            obj.SetAnimationFunctions(xShift, yShift);
            obj.lifeTime = lifeTime;
            obj.gameObject.SetActive(true);
        }
        
        
        /// <summary>
        /// 寻找场景中现有的 Canvas，如果不存在则创建一个新的。
        /// 同时确保场景中存在 EventSystem。
        /// </summary>
        /// <returns>返回场景中的 Canvas 组件。</returns>
        private static Canvas GetOrCreateMainCanvas()
        {
            var existingCanvas = FindFirstObjectByType<Canvas>();
            if (existingCanvas != null)
            {
                EnsureEventSystemExists(); 
                return existingCanvas;
            }

            // 创建 Canvas GameObject
            var canvasGO = new GameObject("Canvas");
            canvasGO.layer = LayerMask.NameToLayer("UI"); 
            var newCanvas = canvasGO.AddComponent<Canvas>();
            newCanvas.renderMode = RenderMode.ScreenSpaceOverlay; 
            
            // 确保有相机，以便RectTransformUtility.ScreenPointToLocalPointInRectangle可以工作
            // 对于ScreenSpaceOverlay，worldCamera可以为null，但为了通用性和健壮性，这里设置为Camera.main，
            // 以防Canvas.renderMode将来调整为ScreenSpaceCamera或WorldSpace
            newCanvas.worldCamera = Camera.main; 

            canvasGO.AddComponent<CanvasScaler>();
            canvasGO.AddComponent<GraphicRaycaster>();
            EnsureEventSystemExists();
            return newCanvas;
        }
        /// <summary>
        /// 检查场景中是否存在 EventSystem，如果不存在则创建一个。
        /// </summary>
        private static void EnsureEventSystemExists()
        {
            var existingEventSystem = FindFirstObjectByType<EventSystem>();
            if (existingEventSystem != null) return;
            var eventSystemGO = new GameObject("EventSystem");
            eventSystemGO.AddComponent<EventSystem>();
            eventSystemGO.AddComponent<StandaloneInputModule>(); // 最常见的输入模块
        }
    }
}