using System.Runtime.CompilerServices;

namespace BansheeEngine
{
    /// <summary>
    /// Contains various builtin resources that are always available.
    /// </summary>
    public static class Builtin
    {
        /// <summary>
        /// Types of builtin meshes that are always available in the engine.
        /// </summary>
        private enum BuiltinMesh // Note: Must match C++ enum BuiltinMesh
        {
            Box, Sphere, Cone, Quad, Disc
        }

        /// <summary>
        /// Returns a pure white texture.
        /// </summary>
        public static SpriteTexture WhiteTexture
        {
            get { return Internal_GetWhiteTexture(); }
        }

        /// <summary>
        /// Returns the default shader to be used with renderables.
        /// </summary>
        public static Shader DiffuseShader
        {
            get { return Internal_GetDiffuseShader(); }
        }

        /// <summary>
        /// Returns a axis aligned box of unit size.
        /// </summary>
        public static Mesh Box
        {
            get { return Internal_GetMesh(BuiltinMesh.Box); }
        }

        /// <summary>
        /// Returns a unit sphere mesh.
        /// </summary>
        public static Mesh Sphere
        {
            get { return Internal_GetMesh(BuiltinMesh.Sphere); }
        }

        /// <summary>
        /// Returns a cone mesh.
        /// </summary>
        public static Mesh Cone
        {
            get { return Internal_GetMesh(BuiltinMesh.Cone); }
        }

        /// <summary>
        /// Returns a quad mesh with unit size edges.
        /// </summary>
        public static Mesh Quad
        {
            get { return Internal_GetMesh(BuiltinMesh.Quad); }
        }

        /// <summary>
        /// Returns a disc mesh with unit radius.
        /// </summary>
        public static Mesh Disc
        {
            get { return Internal_GetMesh(BuiltinMesh.Disc); }
        }

        [MethodImpl(MethodImplOptions.InternalCall)]
        private static extern SpriteTexture Internal_GetWhiteTexture();

        [MethodImpl(MethodImplOptions.InternalCall)]
        private static extern Shader Internal_GetDiffuseShader();

        [MethodImpl(MethodImplOptions.InternalCall)]
        private static extern Mesh Internal_GetMesh(BuiltinMesh mesh);
    }
}