using System;
using System.Collections.Generic;
using System.Linq;
using System.Numerics;
using System.Text;
using System.Threading.Tasks;
using Newtonsoft.Json;
using SharpGLTF.Geometry;
using SharpGLTF.Geometry.VertexTypes;
using SharpGLTF.Materials;
using SharpGLTF.Schema2;

namespace GltfExporter2
{
    public class GltfExporter2
    {
        public static void ExportGltf(string pathToFile, Object3DGroup object3DGroup)
        {
            // create a new gltf model
            var model = ModelRoot.CreateModel();


            var geometryIndex = 0;
            object3DGroup.ForeachMaterialObject(delegate(MaterialObejct3D materialObject3D, object context)
            {
                var diffuse = materialObject3D.Material.Diffuse;

                var diffuseR = diffuse.R / 255.0f;
                var diffuseG = diffuse.G / 255.0f;
                var diffuseB = diffuse.B / 255.0f;
                var diffuseA = diffuse.A / 255.0f;
                var gltfMaterial = new MaterialBuilder()
                    .WithDoubleSide(true)
                    .WithMetallicRoughnessShader()
                    .WithChannelParam("BaseColor", new Vector4(diffuseR, diffuseG, diffuseB, diffuseA));


                var mesh = new MeshBuilder<VertexPosition>("mesh");

                var primitive = mesh.UsePrimitive(gltfMaterial);


                var viSoftGeometry = materialObject3D.Geometry;
                for (var index = 0; index < viSoftGeometry.Indexes.Count; index += 3)
                {
                    var index1 = viSoftGeometry.Indexes[index];
                    var index2 = viSoftGeometry.Indexes[index + 1];
                    var index3 = viSoftGeometry.Indexes[index + 2];

                    var coordinate1 = viSoftGeometry.Coords[index1];
                    var coordinate2 = viSoftGeometry.Coords[index2];
                    var coordinate3 = viSoftGeometry.Coords[index3];

                    var normal1 = viSoftGeometry.Normals[index1];
                    var normal2= viSoftGeometry.Normals[index2];
                    var normal3 = viSoftGeometry.Normals[index3];

                    //primitive.AddTriangle(new VertexPosition(coordinate1.X, coordinate1.Y, coordinate1.Z),
                    //    new VertexPosition(coordinate2.X, coordinate2.Y, coordinate2.Z),
                    //    new VertexPosition(coordinate3.X, coordinate3.Y, coordinate3.Z));

                    var vertexPositionNormal1 = new Vertex<VertexPositionNormal, VertexEmpty, VertexEmpty>
                    {
                        Geometry =
                        {
                            Normal = new Vector3(normal1.X, normal1.Y, normal1.Z),
                            Position = new Vector3(coordinate1.X, coordinate1.Y, coordinate1.Z)
                        }
                    };

                    var vertexPositionNormal2 = new Vertex<VertexPositionNormal, VertexEmpty, VertexEmpty>
                    {
                        Geometry =
                        {
                            Normal = new Vector3(normal2.X, normal2.Y, normal2.Z),
                            Position = new Vector3(coordinate2.X, coordinate2.Y, coordinate2.Z)
                        }
                    };

                    var vertexPositionNormal3 = new Vertex<VertexPositionNormal, VertexEmpty, VertexEmpty>
                    {
                        Geometry =
                        {
                            Normal = new Vector3(normal3.X, normal3.Y, normal3.Z),
                            Position = new Vector3(coordinate3.X, coordinate3.Y, coordinate3.Z)
                        }
                    };

                    primitive.AddTriangle(vertexPositionNormal1, vertexPositionNormal2, vertexPositionNormal3);
                }

                // add all meshes (just one in this case) to the model
                model.CreateMeshes(mesh);

                // create a scene, a node, and assign the first mesh
                model.UseScene("Default")
                    .CreateNode()
                    .WithMesh(model.LogicalMeshes[geometryIndex]);
                geometryIndex++;


            }, null);

            //    // save the model in different formats
            model.SaveGLTF(@"d:\test.gltf", Formatting.Indented);
        }
    }
}