Dashboard/Dashboard.Drawing/Font.cs

using System.Linq;

namespace Dashboard.Drawing
{
    public class FontExtension : DrawExtension
    {
        private FontExtension() : base("DB_Font", Enumerable.Empty<DrawExtension>())
        {
        }

        public static readonly IDrawExtension Instance = new FontExtension();
    }

    public interface IFont : IDrawResource
    {
        public string Family { get; }
        public float Size { get; }
        public FontWeight Weight { get; }
        public FontSlant Slant { get; }
        public FontStretch Stretch { get; }
    }

    public struct NamedFont : IFont
    {
        public IDrawExtension Kind { get; } = Instance;

        public string Family { get; }
        public float Size { get; }
        public FontWeight Weight { get; }
        public FontSlant Slant { get; }
        public FontStretch Stretch { get; }

        public NamedFont(string family, float size, FontWeight weight = FontWeight.Normal,
            FontSlant slant = FontSlant.Normal, FontStretch stretch = FontStretch.Normal)
        {
            Family = family;
            Size = size;
            Weight = weight;
            Slant = slant;
            Stretch = Stretch;
        }

        private static readonly IDrawExtension Instance = new Extension();

        private class Extension : DrawExtension
        {
            public Extension() : base("DB_Font_Named", [FontExtension.Instance])
            {
            }
        }
    }
}