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

namespace BaseGames.Editor
{
    /// <summary>
    /// 集中管理 ScriptableObject 资产的 CRUD 操作（含 Undo 支持）。
    /// </summary>
    public static class AssetOperations
    {
        // ── 创建 ──────────────────────────────────────────────────────────────

        /// <summary>
        /// 弹出 SaveFilePanel 让用户选择路径，创建并返回新资产。
        /// 创建失败或用户取消时返回 null。
        /// </summary>
        public static T Create<T>(string defaultFolder, string defaultName) where T : ScriptableObject
        {
            if (!Directory.Exists(defaultFolder))
                Directory.CreateDirectory(defaultFolder);

            string path = EditorUtility.SaveFilePanelInProject(
                "新建 " + typeof(T).Name,
                defaultName + ".asset",
                "asset",
                "选择保存路径",
                defaultFolder);

            if (string.IsNullOrEmpty(path))
                return null;

            var asset = ScriptableObject.CreateInstance<T>();
            asset.name = Path.GetFileNameWithoutExtension(path);
            AssetDatabase.CreateAsset(asset, path);
            Undo.RegisterCreatedObjectUndo(asset, "Create " + typeof(T).Name);
            AssetDatabase.SaveAssets();
            AssetDatabase.Refresh();
            return asset;
        }

        // ── 重命名 ───────────────────────────────────────────────────────────

        /// <summary>
        /// 重命名资产（同时更新磁盘文件名和 asset.name）。
        /// 返回 (true, null) 成功；(false, errorMsg) 失败。
        /// </summary>
        public static (bool ok, string error) Rename(UnityEngine.Object asset, string newName)
        {
            if (asset == null)                       return (false, "资产为 null");
            if (string.IsNullOrWhiteSpace(newName))  return (false, "名称不能为空");

            newName = newName.Trim();
            string path = AssetDatabase.GetAssetPath(asset);
            if (string.IsNullOrEmpty(path))          return (false, "资产不在 AssetDatabase 中");

            // 先重命名磁盘文件，成功后再修改内部名称，避免 Undo 状态被失败操作污染
            string err = AssetDatabase.RenameAsset(path, newName);
            if (!string.IsNullOrEmpty(err))
                return (false, err);

            Undo.RecordObject(asset, "Rename " + asset.name);
            asset.name = newName;
            EditorUtility.SetDirty(asset);

            AssetDatabase.SaveAssets();
            AssetDatabase.Refresh();
            return (true, null);
        }

        // ── 删除 ─────────────────────────────────────────────────────────────

        /// <summary>弹出确认对话框，确认后删除资产文件。返回是否已删除。</summary>
        public static bool Delete(UnityEngine.Object asset)
        {
            if (asset == null) return false;
            string path = AssetDatabase.GetAssetPath(asset);
            if (string.IsNullOrEmpty(path)) return false;

            if (!EditorUtility.DisplayDialog(
                    "确认删除",
                    $"删除资产：{asset.name}\n路径：{path}\n\n此操作不可撤销。",
                    "删除", "取消"))
                return false;

            AssetDatabase.DeleteAsset(path);
            AssetDatabase.Refresh();
            return true;
        }

        // ── 克隆 ─────────────────────────────────────────────────────────────

        /// <summary>复制资产文件并返回克隆的资产；用户取消或失败时返回 null。</summary>
        public static T Clone<T>(T source, string defaultFolder) where T : ScriptableObject
        {
            if (source == null) return null;
            string srcPath = AssetDatabase.GetAssetPath(source);

            string path = EditorUtility.SaveFilePanelInProject(
                "克隆 " + source.name,
                source.name + "_Copy.asset",
                "asset",
                "选择保存路径",
                defaultFolder);

            if (string.IsNullOrEmpty(path)) return null;

            if (!AssetDatabase.CopyAsset(srcPath, path))
            {
                Debug.LogError($"[AssetOperations] 克隆失败：{srcPath} → {path}");
                return null;
            }

            AssetDatabase.Refresh();
            var clone = AssetDatabase.LoadAssetAtPath<T>(path);
            if (clone != null)
                Undo.RegisterCreatedObjectUndo(clone, "Clone " + source.name);
            return clone;
        }

        // ── 查询 ─────────────────────────────────────────────────────────────

        /// <summary>在 AssetDatabase 中查找所有 T 类型资产。</summary>
        public static List<T> FindAll<T>() where T : ScriptableObject
        {
            var result = new List<T>();
            string[] guids = AssetDatabase.FindAssets("t:" + typeof(T).Name);
            foreach (var guid in guids)
            {
                string p = AssetDatabase.GUIDToAssetPath(guid);
                var asset = AssetDatabase.LoadAssetAtPath<T>(p);
                if (asset != null) result.Add(asset);
            }
            return result;
        }

        // ── GUID 工具 ─────────────────────────────────────────────────────────

        public static string GetGuid(UnityEngine.Object asset)
        {
            if (asset == null) return string.Empty;
            return AssetDatabase.AssetPathToGUID(AssetDatabase.GetAssetPath(asset));
        }

        public static T LoadByGuid<T>(string guid) where T : UnityEngine.Object
        {
            if (string.IsNullOrEmpty(guid)) return null;
            return AssetDatabase.LoadAssetAtPath<T>(AssetDatabase.GUIDToAssetPath(guid));
        }
    }
}