using System.Collections;
using System.Collections.Generic;
using UnityEngine;

[ExecuteInEditMode]
public class MipmapLevelController : MonoBehaviour
{
    [Range(-3, 3)]
    public float mipMapBias = 0f;
    
    private float lastMipMapBias = 0f;
    private List<Renderer> allRenderers = new List<Renderer>();
    
    void OnEnable()
    {
        CollectAllRenderers();
        ApplyMipMapBias();
    }
    
    void OnDisable()
    {
        // 恢复原始设置
        ResetMipMapBias();
    }
    
    void Update()
    {
        // 检查MipMap偏移是否发生变化
        if (mipMapBias != lastMipMapBias)
        {
            ApplyMipMapBias();
            lastMipMapBias = mipMapBias;
        }
    }
    
    void CollectAllRenderers()
    {
        allRenderers.Clear();
        
        // 获取场景中所有的渲染器
        Renderer[] renderers = FindObjectsOfType<Renderer>(true);
        
        foreach (Renderer renderer in renderers)
        {
            allRenderers.Add(renderer);
        }
        
        //Debug.Log($"收集到 {allRenderers.Count} 个渲染器");
    }
    
    void ApplyMipMapBias()
    {
        foreach (Renderer renderer in allRenderers)
        {
            if (renderer == null) continue;
            
            Material[] materials = renderer.sharedMaterials;
            
            for (int i = 0; i < materials.Length; i++)
            {
                if (materials[i] == null) continue;
                
                foreach (string texName in materials[i].GetTexturePropertyNames())
                {
                    if (materials[i].HasProperty(texName))
                    {
                        Texture texture = materials[i].GetTexture(texName);
                        if (texture != null)
                        {
                            texture.mipMapBias = mipMapBias;
                        }
                    }
                }
            }
        }
        
        //Debug.Log($"已应用MipMap偏移：{mipMapBias}");
    }
    
    void ResetMipMapBias()
    {
        foreach (Renderer renderer in allRenderers)
        {
            if (renderer == null) continue;
            
            Material[] materials = renderer.sharedMaterials;
            
            for (int i = 0; i < materials.Length; i++)
            {
                if (materials[i] == null) continue;
                
                foreach (string texName in materials[i].GetTexturePropertyNames())
                {
                    if (materials[i].HasProperty(texName))
                    {
                        Texture texture = materials[i].GetTexture(texName);
                        if (texture != null)
                        {
                            texture.mipMapBias = 0f;
                        }
                    }
                }
            }
        }
        
    }
    
    [ContextMenu("刷新渲染器列表")]
    public void RefreshRenderers()
    {
        CollectAllRenderers();
        ApplyMipMapBias();
    }
}