using System.Collections.Generic;
using System.Threading.Tasks;
using Godot;

public class TestGenerator : IGenerator
{
	public static Vector3I UNIVERSE_SIZE = new(100, 100, 100);
	public static Vector3 SECTOR_SIZE = new(5000, 5000, 5000);
	public static int STARS_PER_SECTOR = 100;
	public static int STARS_PER_SECTOR_VARIANCE = 5;
	public static int SHIPS_PER_SECTOR = 0;
	public static int SHIPS_PER_SECTOR_VARIANCE = 0;
	public static int STATIONS_PER_SECTOR = 0;
	public static int STATIONS_PER_SECTOR_VARIANCE = 0;

	private readonly int threads = 16;

	private RandomNumberGenerator rng;

	public Vector3I GetUniverseSize()
	{
		return UNIVERSE_SIZE;
	}

	public Vector3I GetSectorOffset()
	{
		return new(
			(int)Mathf.Floor(UNIVERSE_SIZE.X / 2),
			(int)Mathf.Floor(UNIVERSE_SIZE.X / 2),
			(int)Mathf.Floor(UNIVERSE_SIZE.X / 2)
		);
	}

	public Vector3 GetSectorSize()
	{
		return SECTOR_SIZE;
	}

	public Universe GenerateUniverse()
	{
		rng = new();

		List<Task> tasks = [];

		Universe universe = new(UNIVERSE_SIZE);
		int countX = Mathf.Clamp(UNIVERSE_SIZE.X / threads, 1, int.MaxValue);

		for (int x = 0; x < UNIVERSE_SIZE.X; x += countX)
		{
			int taskStartX = x;
			int taskCountX = countX;

			Task clusteredTask = Task.Run(() =>
			{
				GenerateClustered(universe, taskStartX, taskCountX);
			});

			tasks.Add(clusteredTask);
		}

		Task.WaitAll([.. tasks]);

		return universe;
	}

	private void GenerateClustered(Universe universe, int startX, int countX)
	{
		int endX = Mathf.Clamp(startX + countX, 0, UNIVERSE_SIZE.X);

		for (int x = startX; x < endX; x++)
		{
			for (int y = 0; y < UNIVERSE_SIZE.Y; y++)
			{
				for (int z = 0; z < UNIVERSE_SIZE.Z; z++)
				{
					universe.Sectors[x, y, z] = GenerateSector(new(x, y, z));
				}
			}
		}
	}

	public Sector GenerateSector(Vector3I coordinates)
	{
		Sector sector = new(coordinates, GetSectorOffset(), SECTOR_SIZE);

		int starCount = rng.RandiRange(
			STARS_PER_SECTOR - STARS_PER_SECTOR_VARIANCE,
			STARS_PER_SECTOR + STARS_PER_SECTOR_VARIANCE
		);
		starCount = Mathf.Clamp(starCount, 0, int.MaxValue);

		for (int i = 0; i < starCount; i++)
		{
			Vector3 localCoordinates = GenerateLocalCoordinates();
			Star star = GenerateStar(sector, localCoordinates);

			sector.GameObjects.Add(star);
		}

		int shipCount = rng.RandiRange(
			SHIPS_PER_SECTOR - SHIPS_PER_SECTOR_VARIANCE,
			SHIPS_PER_SECTOR + SHIPS_PER_SECTOR_VARIANCE
		);
		shipCount = Mathf.Clamp(shipCount, 0, int.MaxValue);

		for (int i = 0; i < shipCount; i++)
		{
			Vector3 localCoordinates = GenerateLocalCoordinates();
			Vessel ship = GenerateShip(sector, localCoordinates);

			sector.GameObjects.Add(ship);
		}

		int stationCount = rng.RandiRange(
			STATIONS_PER_SECTOR - STATIONS_PER_SECTOR_VARIANCE,
			STATIONS_PER_SECTOR + STATIONS_PER_SECTOR_VARIANCE
		);
		stationCount = Mathf.Clamp(stationCount, 0, int.MaxValue);

		for (int i = 0; i < stationCount; i++)
		{
			Vector3 localCoordinates = GenerateLocalCoordinates();
			Vessel station = GenerateStation(sector, localCoordinates);

			sector.GameObjects.Add(station);
		}

		return sector;
	}

	public Star GenerateStar(Sector sector, Vector3 localCoordinates)
	{
		return new Star(sector, localCoordinates);
	}

	public Star GenerateStar(Sector sector)
	{
		return GenerateStar(sector, GenerateLocalCoordinates());
	}

	public Vessel GenerateShip(Sector sector, Vector3 localCoordinates)
	{
		return new Vessel(sector, localCoordinates);
	}

	public Vessel GenerateShip(Sector sector)
	{
		return GenerateShip(sector, GenerateLocalCoordinates());
	}

	public Vessel GenerateStation(Sector sector, Vector3 localCoordinates)
	{
		return new Vessel(sector, localCoordinates);
	}

	public Vessel GenerateStation(Sector sector)
	{
		return GenerateStation(sector, GenerateLocalCoordinates());
	}

	public Vector3 GenerateLocalCoordinates()
	{
		double x = (rng.Randf() - 0.5) * SECTOR_SIZE.X;
		double y = (rng.Randf() - 0.5) * SECTOR_SIZE.Y;
		double z = (rng.Randf() - 0.5) * SECTOR_SIZE.Z;

		return new(x, y, z);
	}
}