/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//
//  D E R E L I C T
//
/// // (c) 2003..2025

using Godot;
using gdcoll = Godot.Collections;
//using System.Linq;





[Tool, GlobalClass]
public partial class AStarGraph : Resource
{
	[Export]
	public gdcoll.Array<Vector3> Points { get; set; } = new();

	[Export]
	public gdcoll.Array<gdcoll.Array<int>> Connections { get; set; } = new();

	private int _nextId = 0;

	public int AddPoint( Vector3 position )
	{
		var id = _nextId++;

		if( Points.Count <= _nextId )
		{
			Points.Resize( _nextId );
			Connections.Resize( _nextId );
		}
		Points[id] = position;
		Connections[id] = new gdcoll.Array<int>();

		return id;
	}



	public void ConnectPoints( int idFrom, int idTo, bool bidirectional = true )
	{
		//if (!Points.ContainsKey(idFrom) || !Points.ContainsKey(idTo)) return;

		//if (!Connections.ContainsKey(idFrom)) Connections[idFrom] = new();
		Connections[idFrom].Add( idTo );

		if( bidirectional )
		{
			//if (!Connections.ContainsKey(idTo)) Connections[idTo] = new();
			Connections[idTo].Add( idFrom );
		}
	}

	public bool ArePointsConnected( int idFrom, int idTo )
	{
		return Connections[idFrom].Contains( idTo );
	}

	public int GetAvailablePointId() => _nextId++;

	public Vector3 GetPointPosition( int id ) => Points[id];

	public gdcoll.Array<int> GetPointConnections( int id ) => Connections[id];

	//public int[] GetPointIds() => Points.Keys.ToArray();


	public int GetClosestPoint( Vector3 position )
	{
		int closestId = -1;
		float closestDistSq = float.MaxValue;

		int curId = 0;
		foreach( var pos in Points )
		{
			if( !pos.IsFinite() )
				continue;

			float distSq = position.DistanceSquaredTo( pos );
			if( distSq < closestDistSq )
			{
				if( Connections[curId].Count > 0 )
				{
					closestDistSq = distSq;
					closestId = curId;
				}
				else
				{
					Points[curId] = Vector3.Inf;
				}
			}
			curId++;
		}
		return closestId;
	}

	public void Clear()
	{
		Points.Clear();
		Connections.Clear();
		_nextId = 0;
	}
}