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;

        private Func<float, float> defaultXoffset = f => Mathf.Sin(f * 3);
        private Func<float, float> defaultYoffset = f => f;
        
        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;
            
        }
        
        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;
            }

            xShift ??= defaultXoffset;
            yShift ??= defaultYoffset;
            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;
        }

        /// <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="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 == null)
            {
                Debug.LogError("TemporaryAnimationLevel is not initialized. Cannot generate non-UI animation.");
                return;
            }

            xShift ??= defaultXoffset;
            yShift ??= defaultYoffset;
            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;
        }
        
        /// <summary>
        /// 生成一个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UI坐标系(RectTransform.anchoredPosition)中的初始位置。</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;
            }

            xShift ??= defaultXoffset;
            yShift ??= defaultYoffset;
            var textObj = Instantiate(temporaryAnimatorUITextPrefab, _temporaryAnimationUILevel.transform);
            textObj.transform.position = position; 
            textObj.Init(str, fps);
            textObj.SetAnimationFunctions(xShift, yShift);
            textObj.lifeTime = lifeTime;
        }
        

        /// <summary>
        /// 生成一个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UI坐标系(RectTransform.anchoredPosition)中的初始位置。</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;
            }

            xShift ??= defaultXoffset;
            yShift ??= defaultYoffset;
            var obj = Instantiate(temporaryAnimatorImageUIPrefab, _temporaryAnimationUILevel.transform);
            obj.transform.position = position;
            obj.Init(sprites, fps);
            obj.SetAnimationFunctions(xShift, yShift);
            obj.lifeTime = lifeTime;
        }
        
        
        /// <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(); // 即使Canvas已存在，也要确保EventSystem存在
                return existingCanvas;
            }

            // 创建 Canvas GameObject
            var canvasGO = new GameObject("Canvas");
            canvasGO.layer = LayerMask.NameToLayer("UI"); // 建议将UI设置为UI层
            // 添加 Canvas 组件
            var newCanvas = canvasGO.AddComponent<Canvas>();
            newCanvas.renderMode = RenderMode.ScreenSpaceOverlay; // 最常见的UI渲染模式
            // 添加其他必要的UI组件
            canvasGO.AddComponent<CanvasScaler>();
            canvasGO.AddComponent<GraphicRaycaster>();
            // 确保场景中存在 EventSystem，以便UI交互（按钮点击等）能正常工作
            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
        }
    }
}