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

public class PrefabManager : EditorWindow
{
    private GameObject selectedPrefab;
    private GameObject prefabInstance;
    private Vector2 scrollPosition;
    private static Dictionary<string, GameObject> prefabReferences = new Dictionary<string, GameObject>();

    [MenuItem("Tools/Prefab Manager")]
    public static void ShowWindow()
    {
        GetWindow<PrefabManager>("预制体管理器");
    }

    private void OnGUI()
    {
        GUILayout.Label("预制体加载与管理", EditorStyles.boldLabel);
        
        // 选择预制体
        EditorGUILayout.Space();
        selectedPrefab = (GameObject)EditorGUILayout.ObjectField("选择预制体", selectedPrefab, typeof(GameObject), false);
        
        EditorGUILayout.Space();
        if (GUILayout.Button("加载预制体"))
        {
            LoadPrefab();
        }

        EditorGUILayout.Space();
        if (prefabInstance != null)
        {
            GUILayout.Label("当前实例: " + prefabInstance.name);
            
            EditorGUILayout.Space();
            if (GUILayout.Button("断开连接"))
            {
                BreakPrefabConnection();
            }
            
            EditorGUILayout.Space();
            if (GUILayout.Button("应用更改到预制体"))
            {
                ApplyChangesToPrefab();
            }
        }

        // 显示已保存的预制体引用
        EditorGUILayout.Space();
        GUILayout.Label("已保存的预制体引用:", EditorStyles.boldLabel);
        
        scrollPosition = EditorGUILayout.BeginScrollView(scrollPosition);
        
        foreach (var pair in prefabReferences)
        {
            EditorGUILayout.BeginHorizontal();
            EditorGUILayout.LabelField(pair.Key, GUILayout.Width(150));
            
            if (pair.Value != null)
            {
                EditorGUILayout.ObjectField(pair.Value, typeof(GameObject), false);
                
                if (GUILayout.Button("选择", GUILayout.Width(60)))
                {
                    Selection.activeObject = pair.Value;
                }
            }
            else
            {
                EditorGUILayout.LabelField("引用丢失");
                if (GUILayout.Button("移除", GUILayout.Width(60)))
                {
                    prefabReferences.Remove(pair.Key);
                }
            }
            EditorGUILayout.EndHorizontal();
        }
        
        EditorGUILayout.EndScrollView();
    }

    private void LoadPrefab()
    {
        if (selectedPrefab == null)
        {
            EditorUtility.DisplayDialog("错误", "请先选择一个预制体", "确定");
            return;
        }

        // 检查是否已存在实例
        if (prefabInstance != null)
        {
            if (!EditorUtility.DisplayDialog("确认", "是否替换当前实例?", "是", "否"))
            {
                return;
            }
            
            DestroyImmediate(prefabInstance);
        }

        // 实例化预制体并保持连接
        prefabInstance = (GameObject)PrefabUtility.InstantiatePrefab(selectedPrefab);
        prefabInstance.name = selectedPrefab.name;
        
        // 保存预制体引用
        string referenceKey = selectedPrefab.name;
        if (!prefabReferences.ContainsKey(referenceKey))
        {
            prefabReferences.Add(referenceKey, selectedPrefab);
        }
        else
        {
            prefabReferences[referenceKey] = selectedPrefab;
        }

        // 记录操作
        Debug.Log("已加载预制体: " + selectedPrefab.name + " 并保持连接");
        
        // 选中新实例
        Selection.activeObject = prefabInstance;
    }

    private void BreakPrefabConnection()
    {
        if (prefabInstance != null && PrefabUtility.IsPartOfPrefabInstance(prefabInstance))
        {
            PrefabUtility.UnpackPrefabInstance(prefabInstance, PrefabUnpackMode.Completely, InteractionMode.UserAction);
            Debug.Log("已断开与预制体的连接");
        }
    }

    private void ApplyChangesToPrefab()
    {
        if (prefabInstance != null && PrefabUtility.IsPartOfPrefabInstance(prefabInstance))
        {
            GameObject prefab = PrefabUtility.GetCorrespondingObjectFromSource(prefabInstance) as GameObject;
            if (prefab != null)
            {
                PrefabUtility.ApplyPrefabInstance(prefabInstance, InteractionMode.UserAction);
                Debug.Log("已将更改应用到预制体: " + prefab.name);
            }
        }
    }

    // 用于在其他脚本中获取保存的预制体引用
    public static GameObject GetPrefabReference(string prefabName)
    {
        if (prefabReferences.ContainsKey(prefabName))
        {
            return prefabReferences[prefabName];
        }
        return null;
    }
}