#if UNITY_EDITOR
using UnityEditor;
using UnityEngine;

public class ReplacWithPrefab : EditorWindow
{
    GameObject prefab;
    string nameFilter = "spotlight_A";

    [MenuItem("Tools/Replace With Prefab")]
    static void Open() => GetWindow<ReplacWithPrefab>();

    void OnGUI()
    {
        prefab = (GameObject)EditorGUILayout.ObjectField("Prefab", prefab, typeof(GameObject), false);
        nameFilter = EditorGUILayout.TextField("Name filter", nameFilter);

        if (GUILayout.Button("Replace") && prefab)
        {
            var all = FindObjectsByType<GameObject>(FindObjectsSortMode.None);
            foreach (var go in all)
            {
                if (!go.name.StartsWith(nameFilter)) continue;

                var instance = (GameObject)PrefabUtility.InstantiatePrefab(prefab, go.transform.parent);
                instance.transform.SetPositionAndRotation(go.transform.position, go.transform.rotation);
                instance.transform.localScale = go.transform.localScale;
                instance.name = go.name;
                Undo.RegisterCreatedObjectUndo(instance, "Replace");
                Undo.DestroyObjectImmediate(go);
            }
        }
    }
}
#endif