using System.Diagnostics;

namespace Shogi.Domain.YetToBeAssimilatedIntoDDD.Pathing;

[DebuggerDisplay("{Direction} - {Distance}")]
public record Path
{
	public Vector2 NormalizedDirection { get; }
	public Distance Distance { get; }

	public Path(Vector2 direction, Distance distance = Distance.OneStep)
	{
		NormalizedDirection = Vector2.Normalize(direction);
		this.Distance = distance;
	}
	public Path Invert() => new(Vector2.Negate(NormalizedDirection), Distance);
}

public static class PathExtensions
{
	public static Path GetNearestPath(this IEnumerable<Path> paths, Vector2 start, Vector2 end)
	{
		if (!paths.DefaultIfEmpty().Any())
		{
			throw new ArgumentException("No paths to get nearest path from.");
		}

		var shortestPath = paths.First();
		foreach (var path in paths.Skip(1))
		{
			var distance = Vector2.Distance(start + path.NormalizedDirection, end); //Normalizing the direction probably broke this.
			var shortestDistance = Vector2.Distance(start + shortestPath.NormalizedDirection, end); // And this.
			if (distance < shortestDistance)
			{
				shortestPath = path;
			}
		}
		return shortestPath;
	}
}