namespace AdventOfCode.Core.Shared.Grid
{
    internal static class IntersectHelpers
    {
        public static bool Intersect(Point one, Point two)
        {
            if (one == null || two == null) return false;

            return one.X == two.X && one.Y == two.Y;
        }

        public static bool Intersect(Line line, Point point)
        {
            if (line == null || point == null) return false;

            if (point.Y != line.Start.Y) return false;

            return point.X >= line.Start.X && point.X <= line.End.X;
        }

        public static bool Intersect(Line one, Line two)
        {
            if (one == null || two == null) return false;

            if (one.Start.Y != two.Start.Y) return false;

            // sort the lines so testing is easier
            (Line first, Line second) = one.Start.X <=two.Start.X ? (one, two) : (two, one);

            return Intersect(first, second.Start) // is the start point of the other line in this line
                || Intersect(first, second.End) // is the end point of the other line in this line
                || (first.Start.X <= second.Start.X && first.End.X >= second.End.X); // is this line fully within the other line
        }
    }
}