using UnityEngine;
using UnityEditor;
using System.Collections.Generic;
using System.Linq;

public class HDRPToURPMaterialConverter : EditorWindow
{
    private List<Material> hdrpMaterials = new List<Material>();
    private List<bool> selected;
    private Vector2 scrollPos;

    [MenuItem("工具/材质/HDRP转URP批量转换器")]
    public static void ShowWindow()
    {
        GetWindow<HDRPToURPMaterialConverter>("HDRP转URP材质");
    }

    private void OnEnable()
    {
        RefreshHDRPMaterials();
    }

    private void RefreshHDRPMaterials()
    {
        hdrpMaterials = AssetDatabase.FindAssets("t:Material")
            .Select(guid => AssetDatabase.GUIDToAssetPath(guid))
            .Select(path => AssetDatabase.LoadAssetAtPath<Material>(path))
            .Where(mat => mat != null && mat.shader != null && mat.shader.name.StartsWith("HDRP/"))
            .ToList();
        selected = new List<bool>(new bool[hdrpMaterials.Count]);
    }

    private void OnGUI()
    {
        EditorGUILayout.Space();
        if (GUILayout.Button("刷新HDRP材质列表"))
        {
            RefreshHDRPMaterials();
        }
        EditorGUILayout.Space();
        if (hdrpMaterials.Count == 0)
        {
            EditorGUILayout.HelpBox("未检测到HDRP材质。", MessageType.Info);
            return;
        }

        EditorGUILayout.BeginHorizontal();
        if (GUILayout.Button("全选"))
        {
            for (int i = 0; i < selected.Count; i++) selected[i] = true;
        }
        if (GUILayout.Button("全不选"))
        {
            for (int i = 0; i < selected.Count; i++) selected[i] = false;
        }
        EditorGUILayout.EndHorizontal();

        EditorGUILayout.LabelField($"检测到HDRP材质数量: {hdrpMaterials.Count}");
        EditorGUILayout.Space();
        scrollPos = EditorGUILayout.BeginScrollView(scrollPos, GUILayout.Height(300));
        for (int i = 0; i < hdrpMaterials.Count; i++)
        {
            EditorGUILayout.BeginHorizontal();
            selected[i] = EditorGUILayout.Toggle(selected[i], GUILayout.Width(20));
            EditorGUILayout.ObjectField(hdrpMaterials[i], typeof(Material), false);
            EditorGUILayout.EndHorizontal();
        }
        EditorGUILayout.EndScrollView();
        EditorGUILayout.Space();

        if (GUILayout.Button("转换选中材质"))
        {
            ConvertSelectedMaterials();
        }
        if (GUILayout.Button("一键全部转换"))
        {
            for (int i = 0; i < selected.Count; i++) selected[i] = true;
            ConvertSelectedMaterials();
        }
    }

    private void ConvertSelectedMaterials()
    {
        int count = 0;
        for (int i = 0; i < hdrpMaterials.Count; i++)
        {
            if (selected[i])
            {
                if (ConvertMaterial(hdrpMaterials[i]))
                    count++;
            }
        }
        AssetDatabase.SaveAssets();
        EditorUtility.DisplayDialog("转换完成", $"成功转换 {count} 个材质。", "确定");
        RefreshHDRPMaterials();
    }

    private bool ConvertMaterial(Material mat)
    {
        if (mat == null) return false;
        Undo.RecordObject(mat, "HDRP材质转URP");
        // 只处理HDRP Lit
        if (mat.shader.name == "HDRP/Lit")
        {
            Shader urpShader = Shader.Find("Universal Render Pipeline/Lit");
            if (urpShader == null)
            {
                Debug.LogError("未找到URP Lit Shader，请确保已安装URP。");
                return false;
            }
            // 备份常用属性
            Color baseColor = mat.HasProperty("_BaseColor") ? mat.GetColor("_BaseColor") : Color.white;
            Texture baseMap = mat.HasProperty("_BaseColorMap") ? mat.GetTexture("_BaseColorMap") : null;
            float metallic = mat.HasProperty("_Metallic") ? mat.GetFloat("_Metallic") : 0f;
            float smoothness = mat.HasProperty("_Smoothness") ? mat.GetFloat("_Smoothness") : 0.5f;
            Texture maskMap = mat.HasProperty("_MaskMap") ? mat.GetTexture("_MaskMap") : null;
            Texture normalMap = mat.HasProperty("_NormalMap") ? mat.GetTexture("_NormalMap") : null;
            float normalScale = mat.HasProperty("_NormalScale") ? mat.GetFloat("_NormalScale") : 1f;
            Texture emissionMap = mat.HasProperty("_EmissiveColorMap") ? mat.GetTexture("_EmissiveColorMap") : null;
            Color emissionColor = mat.HasProperty("_EmissiveColor") ? mat.GetColor("_EmissiveColor") : Color.black;

            mat.shader = urpShader;
            // 还原属性
            if (mat.HasProperty("_BaseMap")) mat.SetTexture("_BaseMap", baseMap);
            if (mat.HasProperty("_BaseColor")) mat.SetColor("_BaseColor", baseColor);
            if (mat.HasProperty("_Metallic")) mat.SetFloat("_Metallic", metallic);
            if (mat.HasProperty("_Smoothness")) mat.SetFloat("_Smoothness", smoothness);
            if (mat.HasProperty("_BumpMap")) mat.SetTexture("_BumpMap", normalMap);
            if (mat.HasProperty("_BumpScale")) mat.SetFloat("_BumpScale", normalScale);
            if (mat.HasProperty("_EmissionMap")) mat.SetTexture("_EmissionMap", emissionMap);
            if (mat.HasProperty("_EmissionColor")) mat.SetColor("_EmissionColor", emissionColor);
            // Metallic/Smoothness贴图（MaskMap）可选迁移到Metallic Map
            if (maskMap != null && mat.HasProperty("_MetallicGlossMap"))
                mat.SetTexture("_MetallicGlossMap", maskMap);
            EditorUtility.SetDirty(mat);
            return true;
        }
        return false;
    }
}