Leetcode 102 - binary tree level order print - write C# code based on one of Java implementation

Leetcode102_binaryTreeLevelOrderPrint.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace BinaryTreeLevelOrderTraversal
{
    class Program
    {
        static void Main(string[] args)
        {
        }
        
        // Definition for a binary tree node.
        public class TreeNode {
            public int val;
            public TreeNode left;
            public TreeNode right;
            public TreeNode(int x) { val = x; }
        }
        /// <summary>
        /// May 3, 2018
        /// I like to write a C# solution based on this blog:
        /// https://leetcode.com/problems/binary-tree-level-order-traversal/discuss/33710/Java-queue-solution-beats-100
        /// </summary>
        public class Solution
        {
            public IList<IList<int>> LevelOrder(TreeNode root)
            {
                var nodes = new List<IList<int>>();
                if (root == null)
                {
                    return nodes;
                }

                var queue = new Queue<TreeNode>();
                queue.Enqueue(root);

                while (queue.Count > 0)
                {
                    int currentLevelSize = queue.Count;

                    var layerNodes = new List<int>(); 

                    int index = 0;
                    while (index < currentLevelSize)
                    {
                        var node = queue.Peek();
                        queue.Dequeue();
                        layerNodes.Add(node.val);

                        if (node.left != null)
                        {
                            queue.Enqueue(node.left); 
                        }
                        // bug - not else if - logic checking 
                        if (node.right != null)
                        {
                            queue.Enqueue(node.right); 
                        }

                        index++; 
                    }

                    nodes.Add(layerNodes); 
                }

                return nodes;
            }
        }
    }
}