using System;

namespace Rectangles
{
    public static class RectanglesTask
    {
        public static bool AreIntersected(Rectangle r1, Rectangle r2)
        {
            var leftFirst = (r1.Left <= r2.Left) && (r1.Right >= r2.Left);
            var leftSecond = (r2.Left <= r1.Left) && (r2.Right >= r1.Left);
            var rightFirst = (r1.Top <= r2.Top) && (r1.Bottom >= r2.Top);
            var rightSecond = (r2.Top <= r1.Top) && (r2.Bottom >= r1.Top);

            return (leftFirst || leftSecond) && (rightFirst || rightSecond);
        }

        public static int IntersectionSquare(Rectangle r1, Rectangle r2)
        {
            if (!AreIntersected(r1, r2))
                return 0;

            var width = Math.Max(r1.Left, r2.Left) - Math.Min(r1.Right, r2.Right);
            var height = Math.Max(r1.Top, r2.Top) - Math.Min(r1.Bottom, r2.Bottom);
            return width * height;
        }

        public static int IndexOfInnerRectangle(Rectangle r1, Rectangle r2)
        {
            if (IsInner(r1, r2))
                return 0;

            return IsInner(r2, r1) ? 1 : -1;
        }

        static bool IsInner(Rectangle r1, Rectangle r2)
        {
            return (r1.Left >= r2.Left) && (r1.Right <= r2.Right)
                && (r1.Top >= r2.Top) && (r1.Bottom <= r2.Bottom);
        }
    }
}