namespace MIConvexHull
{
    /// <summary>
    /// A convex face representation containing adjacency information.
    /// </summary>
    public abstract class ConvexFace<TVertex, TFace>
        where TVertex : IVertex
        where TFace : ConvexFace<TVertex, TFace>
    {
        /// <summary>
        /// Adjacency. Array of length "dimension".
        /// If F = Adjacency[i] then the vertices shared with F are Vertices[j] where j != i.
        /// In the context of triangulation, can be null (indicates the cell is at boundary).
        /// </summary>
        public TFace[] Adjacency { get; set; }

        /// <summary>
        /// The vertices stored in clockwise order (for dimensions 2 - 4, higher dimensions the order is arbitrary).
        /// Unless I accidentally switch some index somewhere in which case the order is CCW. Either way, it is consistent.
        /// 3D Normal = (V[1] - V[0]) x (V[2] - V[1]).
        /// </summary>
        public TVertex[] Vertices { get; set; }

        /// <summary>
        /// The normal vector of the face. Null if used in triangulation.
        /// </summary>
        public double[] Normal { get; set; }
    }

    /// <summary>
    /// A default convex face representation.
    /// </summary>
    /// <typeparam name="TVertex"></typeparam>
    public class DefaultConvexFace<TVertex> : ConvexFace<TVertex, DefaultConvexFace<TVertex>>
        where TVertex : IVertex
    {
    }
}