using UnityEngine;

/// <summary>
/// 材质渲染模式助手类
/// 用于设置材质的正确渲染模式以支持透明度
/// </summary>
public static class MaterialRenderModeHelper
{
    public enum BlendMode
    {
        Opaque,
        Cutout,
        Fade,   // Traditional transparency (ZWrite OFF)
        Transparent, // Physically based transparency (ZWrite OFF)
        AlphaBlendWithDepth // Alpha blend with depth write (ZWrite ON) - 解决Body显示问题
    }

    /// <summary>
    /// 设置材质的渲染模式
    /// </summary>
    /// <param name="material">要设置的材质</param>
    /// <param name="blendMode">渲染模式</param>
    public static void SetMaterialRenderMode(Material material, BlendMode blendMode)
    {
        switch (blendMode)
        {
            case BlendMode.Opaque:
                material.SetInt("_SrcBlend", (int)UnityEngine.Rendering.BlendMode.One);
                material.SetInt("_DstBlend", (int)UnityEngine.Rendering.BlendMode.Zero);
                material.SetInt("_ZWrite", 1);
                material.DisableKeyword("_ALPHATEST_ON");
                material.DisableKeyword("_ALPHABLEND_ON");
                material.DisableKeyword("_ALPHAPREMULTIPLY_ON");
                material.renderQueue = -1;
                break;
            case BlendMode.Cutout:
                material.SetInt("_SrcBlend", (int)UnityEngine.Rendering.BlendMode.One);
                material.SetInt("_DstBlend", (int)UnityEngine.Rendering.BlendMode.Zero);
                material.SetInt("_ZWrite", 1);
                material.EnableKeyword("_ALPHATEST_ON");
                material.DisableKeyword("_ALPHABLEND_ON");
                material.DisableKeyword("_ALPHAPREMULTIPLY_ON");
                material.renderQueue = (int)UnityEngine.Rendering.RenderQueue.AlphaTest;
                break;
            case BlendMode.Fade:
                material.SetInt("_SrcBlend", (int)UnityEngine.Rendering.BlendMode.SrcAlpha);
                material.SetInt("_DstBlend", (int)UnityEngine.Rendering.BlendMode.OneMinusSrcAlpha);
                material.SetInt("_ZWrite", 0);
                material.DisableKeyword("_ALPHATEST_ON");
                material.EnableKeyword("_ALPHABLEND_ON");
                material.DisableKeyword("_ALPHAPREMULTIPLY_ON");
                material.renderQueue = (int)UnityEngine.Rendering.RenderQueue.Transparent;
                break;
            case BlendMode.Transparent:
                material.SetInt("_SrcBlend", (int)UnityEngine.Rendering.BlendMode.One);
                material.SetInt("_DstBlend", (int)UnityEngine.Rendering.BlendMode.OneMinusSrcAlpha);
                material.SetInt("_ZWrite", 0);
                material.DisableKeyword("_ALPHATEST_ON");
                material.DisableKeyword("_ALPHABLEND_ON");
                material.EnableKeyword("_ALPHAPREMULTIPLY_ON");
                material.renderQueue = (int)UnityEngine.Rendering.RenderQueue.Transparent;
                break;
            case BlendMode.AlphaBlendWithDepth:
                // 关键修复：保持深度写入的透明混合模式
                material.SetInt("_SrcBlend", (int)UnityEngine.Rendering.BlendMode.SrcAlpha);
                material.SetInt("_DstBlend", (int)UnityEngine.Rendering.BlendMode.OneMinusSrcAlpha);
                material.SetInt("_ZWrite", 1); // 保持深度写入，这样Body即使单独存在也能正确显示
                material.DisableKeyword("_ALPHATEST_ON");
                material.EnableKeyword("_ALPHABLEND_ON");
                material.DisableKeyword("_ALPHAPREMULTIPLY_ON");
                // 使用较早的渲染队列，确保在其他透明物体之前渲染
                material.renderQueue = (int)UnityEngine.Rendering.RenderQueue.Geometry + 450;
                break;
        }
    }

    /// <summary>
    /// 自动检测并设置合适的渲染模式
    /// </summary>
    /// <param name="material">材质</param>
    /// <param name="alpha">透明度值</param>
    public static void AutoSetRenderMode(Material material, float alpha)
    {
        if (alpha >= 1.0f)
        {
            SetMaterialRenderMode(material, BlendMode.Opaque);
        }
        else
        {
            SetMaterialRenderMode(material, BlendMode.AlphaBlendWithDepth);
        }
    }

    /// <summary>
    /// 专门为Body设置渲染模式
    /// 确保Body在单独显示时也能正确显示
    /// </summary>
    /// <param name="material">Body材质</param>
    /// <param name="alpha">透明度值</param>
    public static void SetBodyRenderMode(Material material, float alpha)
    {
        if (alpha >= 1.0f)
        {
            SetMaterialRenderMode(material, BlendMode.Opaque);
        }
        else
        {
            // 对于Body，始终使用保持深度写入的透明模式
            SetMaterialRenderMode(material, BlendMode.AlphaBlendWithDepth);
        }
    }
}