using System.Collections;
using DG.Tweening;
using UnityEngine;
using UnityEngine.UI;

namespace AibisDream.Framework
{
    /// <summary>
    /// UI Image窗帘展开效果工具类（使用Shader实现）
    /// 实现从左到右的展开动画，保持图片原始宽高比不被压扁
    /// </summary>
    public static class CurtainRevealKit
    {
        private static readonly int RevealProgressPropertyID = Shader.PropertyToID("_RevealProgress");
        private static readonly int EdgeSoftnessPropertyID = Shader.PropertyToID("_EdgeSoftness");
        
        /// <summary>
        /// 从左到右显示图片（窗帘拉开效果），使用Shader实现，保持图片原始宽高比
        /// </summary>
        /// <param name="image">目标Image组件</param>
        /// <param name="duration">动画时长</param>
        /// <param name="easeType">缓动类型</param>
        /// <param name="edgeSoftness">边缘柔化程度（0-0.1）</param>
        /// <returns>协程</returns>
        public static IEnumerator RevealFromLeftAsync(this Image image, float duration = 1f, 
            Ease easeType = Ease.OutQuad, float edgeSoftness = 0.02f)
        {
            image.gameObject.SetActive(true);
            
            // 确保Image有Material实例（避免影响其他使用相同Material的对象）
            Material material = EnsureMaterialInstance(image);
            
            // 设置边缘柔化
            material.SetFloat(EdgeSoftnessPropertyID, edgeSoftness);
            
            // 初始状态：进度为0（完全隐藏）
            material.SetFloat(RevealProgressPropertyID, 0f);
            
            // 动画：进度从0到1
            float currentProgress = 0f;
            Tweener tween = DOTween.To(
                () => currentProgress,
                value =>
                {
                    currentProgress = value;
                    material.SetFloat(RevealProgressPropertyID, value);
                },
                1f,
                duration
            ).SetEase(easeType);
            
            yield return tween.WaitForCompletion();
        }
        
        /// <summary>
        /// 同步版本：从左到右显示图片
        /// </summary>
        /// <param name="image">目标Image组件</param>
        /// <param name="duration">动画时长</param>
        /// <param name="easeType">缓动类型</param>
        /// <param name="edgeSoftness">边缘柔化程度（0-0.1）</param>
        public static void RevealFromLeft(this Image image, float duration = 1f, 
            Ease easeType = Ease.OutQuad, float edgeSoftness = 0.02f)
        {
            image.gameObject.SetActive(true);
            
            Material material = EnsureMaterialInstance(image);
            material.SetFloat(EdgeSoftnessPropertyID, edgeSoftness);
            material.SetFloat(RevealProgressPropertyID, 0f);
            
            float currentProgress = 0f;
            DOTween.To(
                () => currentProgress,
                value =>
                {
                    currentProgress = value;
                    material.SetFloat(RevealProgressPropertyID, value);
                },
                1f,
                duration
            ).SetEase(easeType);
        }
        
        /// <summary>
        /// 设置窗帘展开进度（手动控制）
        /// </summary>
        /// <param name="image">目标Image组件</param>
        /// <param name="progress">进度值（0-1）</param>
        /// <param name="edgeSoftness">边缘柔化程度（0-0.1）</param>
        public static void SetRevealProgress(this Image image, float progress, float edgeSoftness = 0.02f)
        {
            if (image == null || image.material == null) return;
            
            Material material = EnsureMaterialInstance(image);
            material.SetFloat(EdgeSoftnessPropertyID, edgeSoftness);
            material.SetFloat(RevealProgressPropertyID, Mathf.Clamp01(progress));
        }
        
        /// <summary>
        /// 重置窗帘展开效果（恢复原始状态）
        /// </summary>
        /// <param name="image">目标Image组件</param>
        public static void ResetReveal(this Image image)
        {
            if (image == null || image.material == null) return;
            
            Material material = EnsureMaterialInstance(image);
            material.SetFloat(RevealProgressPropertyID, 1f);
        }
        
        /// <summary>
        /// 确保Material有独立实例（避免影响其他对象）
        /// </summary>
        private static Material EnsureMaterialInstance(Image image)
        {
            if (image.material == null)
            {
                // 如果没有Material，尝试加载Shader
                Shader shader = Shader.Find("UI/CurtainReveal");
                if (shader == null)
                {
                    Debug.LogError("找不到Shader: UI/CurtainReveal，请确保Shader已正确导入");
                    return null;
                }
                image.material = new Material(shader);
            }
            else if (image.material.shader.name != "UI/CurtainReveal")
            {
                // 如果Material的Shader不对，创建新的Material
                Shader shader = Shader.Find("UI/CurtainReveal");
                if (shader == null)
                {
                    Debug.LogError("找不到Shader: UI/CurtainReveal，请确保Shader已正确导入");
                    return image.material;
                }
                image.material = new Material(shader);
                // 复制原始纹理和颜色
                if (image.sprite != null)
                {
                    image.material.SetTexture("_MainTex", image.sprite.texture);
                }
                image.material.SetColor("_Color", image.color);
            }
            else if (image.material.name.Contains("(Instance)") == false)
            {
                // 如果Material不是实例，创建实例以避免影响其他对象
                image.material = new Material(image.material);
            }
            
            return image.material;
        }
    }
}