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

public class GridManager : MonoBehaviour
{
    #region Statication

    public static GridManager instance;

    private void Awake()
    {
        if (instance != null && instance != this)
        {
            Destroy(gameObject);
            return;
        }
        instance = this;
    }

    #endregion
    [SerializeField] private int width;
    [SerializeField] private int height;

    [SerializeField] private TileObject tilePrefab;
    
    [SerializeField] Camera cam;

    private Dictionary<Vector2, TileObject> allTiles = new();
    private void Start()
    {
        GenerateGrid();
        cam.transform.position = new Vector3((float)width / 2, (float)height / 2, 0);
        foreach (PlayerEntity player in TurnHandler.instance.playerEntities)
        {
            player.currentTile = GetTile(player.transform.position);
        }
        foreach (Enemy enemy in TurnHandler.instance.enemyEntities)
        {
            enemy.currentTile = GetTile(enemy.transform.position);
        }
    }

    private void GenerateGrid()
    {
        for (int x = 0; x < width; x++)
        {
            for (int y = 0; y < height; y++)
            {
                Vector2 pos = new Vector2(x - ((float)width / 2) + 0.5f, y - ((float)height / 2) + 0.5f);
                TileObject newTile = Instantiate(tilePrefab, pos, Quaternion.identity);
                newTile.name = $"Tile {x} {y}";
                allTiles[pos] = newTile;
            }
        }
        GetTileNeighbors();
    }

    private void GetTileNeighbors()
    {
        for (int x = 0; x < width; x++)
        {
            for (int y = 0; y < height; y++)
            {
                Vector2 pos = new Vector2(x - ((float)width / 2) + 0.5f, y - ((float)height / 2) + 0.5f);
                TileObject currentTile = allTiles[pos];
                if (GetTile(pos + Vector2.up)) { currentTile.neighbors.Add(GetTile(pos+Vector2.up));}
                if (GetTile(pos + Vector2.down)) { currentTile.neighbors.Add(GetTile(pos+Vector2.down));}
                if (GetTile(pos + Vector2.left)) { currentTile.neighbors.Add(GetTile(pos+Vector2.left));}
                if (GetTile(pos + Vector2.right)) { currentTile.neighbors.Add(GetTile(pos+Vector2.right));}
            }
        }
    }

    public TileObject GetTile(Vector2 pos)
    {
        if (allTiles.TryGetValue(pos, out TileObject tile))
        {
            return tile;
        }
        return null;
    }
}