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

namespace Core.Editor
{
    public class RecenterParentTool
    {
        [MenuItem("Tools/Recenter Parent")]
        public static void RecenterParent()
        {
            if(Selection.gameObjects.Length != 1)
                return;

            Transform parent = Selection.gameObjects[0].transform;
            Vector3 center = Vector3.zero;

            var undoObjects = new List<Object> {
                parent
            };

            int childCount = parent.childCount;
            int activeCount = 0;
            for (int i = 0; i < childCount; i++)
            {
                Transform child = parent.GetChild(i);
                undoObjects.Add(child);
                if(child.gameObject.activeSelf)
                {
                    center += child.position;
                    activeCount++;
                }
            }

            Undo.RecordObjects(undoObjects.ToArray(), "Recenter parent");

            center /= activeCount;
            Vector3 translation = center - parent.position;
            parent.position = center;
            for (int i = 0; i < childCount; i++)
            {
                Transform child = parent.GetChild(i);
                child.position -= translation;
            }

        }
    }
}