using System.Collections.Generic;
using TriangleNet.Geometry;

namespace TriangleNet.Topology.DCEL
{
	public class Vertex : Point
	{
		internal HalfEdge leaving;

		public HalfEdge Leaving
		{
			get
			{
				return leaving;
			}
			set
			{
				leaving = value;
			}
		}

		public Vertex(double x, double y)
			: base(x, y)
		{
		}

		public Vertex(double x, double y, HalfEdge leaving)
			: base(x, y)
		{
			this.leaving = leaving;
		}

		public IEnumerable<HalfEdge> EnumerateEdges()
		{
			HalfEdge edge = Leaving;
			int first = edge.ID;
			do
			{
				yield return edge;
				edge = edge.Twin.Next;
			}
			while (edge.ID != first);
		}

		public override string ToString()
		{
			return $"V-ID {id}";
		}
	}
}