using Godot;
using System;
using System.Collections.Generic;
using System.Linq;

public partial class Map : TileMapLayer
{
    public int _minX, _maxX, _minY, _maxY, _mainSource = 0;
    public string _isSolidString = "is_solid";
    public Vector2 _cellSize, _sizeInPixels, _sizeInCells;
    public Vector2I _pathTakenAtlasCoordinates = new Vector2I(4, 0);
    public List<Vector2I> _leftmostColumn, _rightmostColumn, _topRow, _bottomRow;
    public AStarGrid2D _astar = new();

    public override void _Ready()
    {
        base._Ready();
        _cellSize = TileSet.TileSize;
        List<Vector2I> cells = GetUsedCells().ToList();
        _minX = cells.Min(c => c.X);
        _maxX = cells.Max(c => c.X);
        _minY = cells.Min(c => c.Y);
        _maxY = cells.Max(c => c.Y);
        _leftmostColumn = [.. cells.Where(c => c.X == _minX)];
        _rightmostColumn = [.. cells.Where(c => c.X == _maxX)];
        _topRow = [.. cells.Where(c => c.Y == _minY)];
        _bottomRow = [.. cells.Where(c => c.Y == _maxY)];

        _sizeInCells = new Vector2(_topRow.Count, _leftmostColumn.Count);
        _sizeInPixels = _sizeInCells * _cellSize;

        SetupAstar();
    }
    
    public Vector2 GetCellPositionFromAddress(Vector2I CELL_ADDRESS)
    {
        return GlobalPosition + CELL_ADDRESS * _cellSize + _cellSize / 2;
    }

    public bool IsCellSolid(Vector2I CELL_TO_CHECK)
    {
        return (bool)GetCellTileData(CELL_TO_CHECK).GetCustomData(_isSolidString);
    }

    public void SetupAstar()
    {
        _astar.Region = new Rect2I(_minX, _minY, _topRow.Count, _leftmostColumn.Count);
        _astar.CellSize = _cellSize;
        _astar.DefaultComputeHeuristic = AStarGrid2D.Heuristic.Manhattan;
        _astar.DiagonalMode = AStarGrid2D.DiagonalModeEnum.Never;
        _astar.Update();
        List<Vector2I> cells = [.. GetUsedCells()];
        for (int i = 0; i < cells.Count; i++)
        {
            _astar.SetPointSolid(cells[i], IsCellSolid(cells[i]));
        }
    }

    public List<Vector2I> GetPath(Vector2I FROM, Vector2I TO, bool INCLUDE_FROM = false, bool SHOW_PATH = false)
    {
        List<Vector2I> pathTaken = [.. _astar.GetIdPath(FROM, TO)];
        if (SHOW_PATH)
        {
            for (int i = 0; i < pathTaken.Count; i++)
            {
                Vector2I cell = pathTaken[i];
                SetCell(cell, _mainSource, _pathTakenAtlasCoordinates);
            }
        }
        if (!INCLUDE_FROM)
        {
            pathTaken.Remove(FROM);
        }
        return pathTaken;
    }

}