using System.Collections.Generic;
using UnityEditor;
using UnityEngine;
 
public static class LightProbeGroupMerger
{
    const string MergedLightProbeGroupName = "MergedLightProbeGroup";
 
    [MenuItem("Tools/Lights/Merge Light Probe Groups")]
    static void MergeLightProbeGroups()
    {
        var lightProbeGroups = GameObject.FindObjectsOfType<LightProbeGroup>();
        if (lightProbeGroups.Length > 1)
        {
            // Collect light probe positions from all light probe groups in the scene.
            var mergedLightProbePositions = new List<Vector3>();
            foreach (var lightProbeGroup in lightProbeGroups)
            {
                foreach (var lightProbePosition in lightProbeGroup.probePositions)
                {
                    mergedLightProbePositions.Add(lightProbeGroup.transform.TransformPoint(lightProbePosition));
                }
            }
 
            // Create a new light probe group that merges all the light probe positions.
            var newGameObject = new GameObject(MergedLightProbeGroupName);
            Undo.RegisterCreatedObjectUndo(newGameObject, $"Created {MergedLightProbeGroupName}");
            var mergedLightProbeGroup = newGameObject.AddComponent<LightProbeGroup>();
            mergedLightProbeGroup.probePositions = mergedLightProbePositions.ToArray();
 
            // Destroy the old individual light probe groups.
            foreach (var lightProbeGroup in lightProbeGroups)
            {
                if (lightProbeGroup != null && lightProbeGroup.gameObject != null)
                {
                    Undo.DestroyObjectImmediate(lightProbeGroup.gameObject);
                }
            }
 
            Debug.Log($"Merged {mergedLightProbePositions.Count} light probes from {lightProbeGroups.Length} light probe groups into '{MergedLightProbeGroupName}'.");
 
            Selection.activeObject = newGameObject;
        }
    }
}