using System;
using System.Collections.Generic;

namespace TriangleNet.Geometry
{
	public class Rectangle
	{
		private double xmin;

		private double ymin;

		private double xmax;

		private double ymax;

		public double Left => xmin;

		public double Right => xmax;

		public double Bottom => ymin;

		public double Top => ymax;

		public double Width => xmax - xmin;

		public double Height => ymax - ymin;

		public Rectangle()
		{
			xmin = (ymin = double.MaxValue);
			xmax = (ymax = double.MinValue);
		}

		public Rectangle(Rectangle other)
			: this(other.Left, other.Bottom, other.Right, other.Top)
		{
		}

		public Rectangle(double x, double y, double width, double height)
		{
			xmin = x;
			ymin = y;
			xmax = x + width;
			ymax = y + height;
		}

		public void Resize(double dx, double dy)
		{
			xmin -= dx;
			xmax += dx;
			ymin -= dy;
			ymax += dy;
		}

		public void Expand(Point p)
		{
			xmin = Math.Min(xmin, p.x);
			ymin = Math.Min(ymin, p.y);
			xmax = Math.Max(xmax, p.x);
			ymax = Math.Max(ymax, p.y);
		}

		public void Expand(IEnumerable<Point> points)
		{
			foreach (Point point in points)
			{
				Expand(point);
			}
		}

		public void Expand(Rectangle other)
		{
			xmin = Math.Min(xmin, other.xmin);
			ymin = Math.Min(ymin, other.ymin);
			xmax = Math.Max(xmax, other.xmax);
			ymax = Math.Max(ymax, other.ymax);
		}

		public bool Contains(double x, double y)
		{
			if (x >= xmin && x <= xmax && y >= ymin)
			{
				return y <= ymax;
			}
			return false;
		}

		public bool Contains(Point pt)
		{
			return Contains(pt.x, pt.y);
		}

		public bool Contains(Rectangle other)
		{
			if (xmin <= other.Left && other.Right <= xmax && ymin <= other.Bottom)
			{
				return other.Top <= ymax;
			}
			return false;
		}

		public bool Intersects(Rectangle other)
		{
			if (other.Left < xmax && xmin < other.Right && other.Bottom < ymax)
			{
				return ymin < other.Top;
			}
			return false;
		}
	}
}