using System;
using UnityEditor;
using UnityEngine;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text.RegularExpressions;

public class FindMissingPrefabs : EditorWindow
{
    [MenuItem("Tools/Find Missing Prefabs")]
    static void Init()
    {
        GetWindow<FindMissingPrefabs>("Find Missing Prefabs").Show();
    }

    private List<GameObject> missingPrefabs = new List<GameObject>();

    void OnGUI()
    {
        if (GUILayout.Button("Find Missing Prefabs in Scene"))
        {
            FindMissing();
        }

        if (missingPrefabs.Count > 0)
        {
            GUILayout.Label("Missing Prefabs Found:", EditorStyles.boldLabel);
            foreach (var obj in missingPrefabs.Take(32))
            {
                if (GUILayout.Button(obj.name))
                {
                    Selection.activeGameObject = obj;

                    AutoFix(obj);
                }
            }
        }
        else
        {
            GUILayout.Label("No missing prefabs found.");
        }
    }

    void FindMissing()
    {
        missingPrefabs.Clear();
        GameObject[] allObjects = GameObject.FindObjectsOfType<GameObject>();

        foreach (GameObject obj in allObjects)
        {
            PrefabAssetType prefabType = PrefabUtility.GetPrefabAssetType(obj);
            if (prefabType == PrefabAssetType.MissingAsset)
            {
                if (PrefabUtility.IsAnyPrefabInstanceRoot(obj) is false)continue;
                AutoFix(obj);
                    missingPrefabs.Add(obj);
            }
        }
    }

    private bool AutoFix(GameObject obj)
    {
        // 解析 name（括号前的部分）
        Match nameMatch = Regex.Match(obj.name, @"^(.+?)\s*\(");

        var name = nameMatch.Success ? nameMatch.Groups[1].Value : "N/A";
        if (nameMatch.Success is false)
        {
            Debug.LogWarning("未能解析到Name");
            return false;
        }
        // 解析 guid
        Match guidMatch = Regex.Match(obj.name, @"guid:\s*([a-f0-9]{32})");

        if (guidMatch.Success is false)
        {
            Debug.LogWarning("未能解析到GUID");
            return false;
        }
        var guid = guidMatch.Success ? guidMatch.Groups[1].Value : "N/A";

        var searchStr =name+ @" t:prefab";

        var searchPrefabs = AssetDatabase.FindAssets(searchStr);
                    
        Debug.Log($"找到:{name}有关的{searchStr}结果:\n"+string.Join("\n",searchPrefabs));

        var errorGuid = string.Empty;
        
        switch (searchPrefabs.Length)
        {
            case > 1:
            {
                try
                {
                    foreach (var searchId in searchPrefabs)
                    {
                        var prefabName = AssetDatabase.GUIDToAssetPath(searchId);
                        var prefab = AssetDatabase.LoadAssetAtPath<GameObject>(prefabName);
                        if (prefab.name == name)
                        {
                            errorGuid = searchId;
                            throw new OperationCanceledException();
                        }
                    }
                    
                    Debug.LogWarning($"找到的结果有:{searchPrefabs.Length},无法自动修复");
                    return false;
                }
                catch (OperationCanceledException)
                {
                }
            }
                break;
            case 1:
            {
                errorGuid = searchPrefabs[0];
            }
           
                break;
            case 0:
            {
                Debug.Log("未找到");
            }
                break;
        }
        
      
        var path = AssetDatabase.GUIDToAssetPath(errorGuid);
        var metaPath = path + ".meta";
        metaPath = Path.Combine(Environment.CurrentDirectory, metaPath);
        if (File.Exists(metaPath) is false)
        {
            Debug.Log($"Meta路径未找到:{{metaPath}}");
            return false;
        }

        var str = File.ReadAllText(metaPath);

        str = str.Replace(searchPrefabs[0], guid);
                    
        File.WriteAllText(metaPath, str);
                    
        Debug.Log($"{name}已修复");

        return true;
    }
}