using Godot;
using System;

public partial class Line2d : Line2D
{
	private TestScene Test { get; set; }
	public Vector2 Start => Test.A.Position;
	public Vector2 End => Test.B.Position;
	public float CurveRate { get; set; } = 20;
	public int CDir { get; set; } = 1;

	private void MakeCurve(float curveRate=20f, int cDir = 1)
	{
		Vector2[] xs = new Vector2[17];
		int[] x2 = new[] { 4, 12 };
		int[] x3 = new[] { 2, 6, 10, 14};
		int[] x4 = new[] { 1, 3, 5, 7, 9, 11, 13, 15 };
		Vector2 vd = End - Start;
		Vector2 nor = vd.Rotated(Mathf.Pi / 2 * cDir);
		Vector2 center = vd / 2 + 4f * nor / curveRate;
		xs[0] = Start;
		xs[16] = End;
		xs[8] = center + xs[0];
		foreach (int i in x2)
		{
			Vector2 v = xs[i + 4] - xs[i - 4];
			Vector2 n = v.Rotated(Mathf.Pi / 2 * cDir);
			Vector2 w = v / 2 + 2f * n / curveRate;
			xs[i] = w + xs[i - 4];
		}

		foreach (int i in x3)
		{
			Vector2 v = xs[i + 2] - xs[i - 2];
			Vector2 n = v.Rotated(Mathf.Pi / 2 * cDir);
			Vector2 w = v / 2 + n / curveRate;
			xs[i] = w + xs[i - 2];
		}

		foreach (int i in x4)
		{
			Vector2 v = xs[i + 1] - xs[i - 1];
			Vector2 n = v.Rotated(Mathf.Pi / 2 * cDir);
			Vector2 w = v / 2 + n / curveRate;
			xs[i] = w + xs[i - 1];
		}

		Points = xs;
	}

	private void T()
	{
		Points = new[] { new Vector2(1, 1), new Vector2(2, 3) };
		GD.Print(Points.Length);
	}

	// Called when the node enters the scene tree for the first time.
	public override void _Ready()
	{
		Test = GetParent<TestScene>();
		
		GD.Print("Ready");
	}

	// Called every frame. 'delta' is the elapsed time since the previous frame.
	public override void _Process(double delta)
	{
		//T();
		MakeCurve(CurveRate, CDir);
	}
}