using System;

using System.Collections.Generic;

namespace Assistance {

	public class GuidelineLine: Guideline {

		protected Point p0, p1;

		protected Point direction;

		public GuidelineLine(Point p0, Point p1) {

			this.p0 = p0;

			this.p1 = p1;

			direction = (p1 - p0).normalize();

		}

		public override void draw(Cairo.Context context, bool active) {

			Point pp0 = p0;

			Point pp1 = p1;

			Rectangle bounds = Drawing.Helper.getBounds(context);

			Geometry.truncateInfiniteLine(bounds, ref pp0, ref pp1);

			context.Save();

			(active ? penActive : pen).apply(context);

			context.MoveTo(pp0.x, pp0.y);

			context.LineTo(pp1.x, pp1.y);

			context.Stroke();

			context.Restore();

		}

		public override Track.WayPoint transformPoint(Track.WayPoint p) {

			Track.WayPoint np = p;

			np.point.position = Point.dot(p.point.position - p0, direction)*direction + p0;

			np.tangent.position = direction;

			return np;

		}

	}

}