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

public class OctreeManager : MonoBehaviour
{

	public GameObject[] parents;
	private float cellSize = 250f;

	private Dictionary<Vector2Int, List<GameObject>> grid = new Dictionary<Vector2Int, List<GameObject>>();

	// Start is called before the first frame update
	void Start()
	{
		//get all objects with mapzone tag, assign to parents array
		parents = GameObject.FindGameObjectsWithTag("mapzone");


		for (int i = 0; i < parents.Length; i++)
		{
			GameObject[] children = getChildren(parents[i]);
			if (children == null) return;
			//get all children of parents[i]
			for (int j = 0; j < children.Length; j++)
			{
				Vector3 position = children[j].transform.position;
				Vector2Int cell = new Vector2Int(
					Mathf.FloorToInt(position.x / cellSize),
					Mathf.FloorToInt(position.z / cellSize));

				if (!grid.ContainsKey(cell))
				{
					grid[cell] = new List<GameObject>();
				}

				grid[cell].Add(children[j]);
				children[j].SetActive(false);
			}
		}

	}

	// Update is called once per frame
	void Update()
	{
		Vector3 playerPosition = Player.Instance.transform.position;
		Vector2Int playerCell = new Vector2Int(
			Mathf.FloorToInt(playerPosition.x / cellSize),
			Mathf.FloorToInt(playerPosition.z / cellSize));

		// Iterate through neighboring cells
		for (int x = playerCell.x - 1; x <= playerCell.x + 1; x++)
		{
			for (int y = playerCell.y - 1; y <= playerCell.y + 1; y++)
			{

				Vector2Int cell = new Vector2Int(x, y);
				if (grid.ContainsKey(cell))
				{
					foreach (var obj in grid[cell])
					{
						// Compare squared distances for faster calculation
						Vector2 offset = new Vector2(obj.transform.position.x, obj.transform.position.z) - new Vector2(playerPosition.x, playerPosition.z);
						float distanceSquared = Vector2.SqrMagnitude(offset);

						// Set your threshold distance squared here
						float hideDistanceSquared = 15000f;

						if (distanceSquared <= hideDistanceSquared)
						{
							obj.SetActive(true); // Show the object
						}
						else
						{
							obj.SetActive(false); // Hide the object
						}
					}
				}

			}
		}
	}

	private GameObject[] getChildren(GameObject g)
	{

		if (g.transform.childCount == 0)
		{
			return null;
		}
		else
		{
			GameObject[] children = new GameObject[g.transform.childCount];
			for (int i = 0; i < g.transform.childCount; i++)
			{
				children[i] = g.transform.GetChild(i).gameObject;
			}
			return children;
		}
	}
}