using System;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics;
using global::System.Drawing;
using Bitmap = System.Drawing.Bitmap;
using Color = System.Drawing.Color;
using Image = System.Drawing.Image;
using System.Globalization;
using System.IO;
using System.Linq;
using System.Reflection;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Security;
using System.Text;
using global::System.Threading;
using System.Threading.Tasks;
using global::System.Windows.Forms;
using System.Xml.Linq;
using Microsoft.VisualBasic;
using Microsoft.VisualBasic.CompilerServices;
using OpenTK;
using OpenTK.Graphics.OpenGL;
using Pilz.S3DFileParser;
using Pilz.Drawing.Drawing3D.OpenGLFactory.RenderingN;

namespace RenderingN
{
    public partial class Renderer
    {
        private Object3D obj3d;
        private Dictionary<Image, int> dicTextureIDs = new Dictionary<Image, int>();
        private Dictionary<Color, int> dicColorIDs = new Dictionary<Color, int>();
        private Bitmap emptyTexture = null;
        private Bitmap lineTexture = null;
        private Bitmap selectedLineTexture = null;

        public float ModelScaling { get; set; } = 1.0f;
        public bool HasRendered { get; private set; } = false;
        public List<global::System.Object> SelectedElements { get; private set; }
        private Dictionary<Mesh, int> VertexBuffers { get; set; } = new Dictionary<Mesh, int>();
        private Dictionary<Mesh, List<int>> IndicesBuffers { get; set; } = new Dictionary<Mesh, List<int>>();
        private Dictionary<Mesh, int> UVBuffers { get; set; } = new Dictionary<Mesh, int>();
        private Dictionary<Mesh, int> VertexColorBuffers { get; set; } = new Dictionary<Mesh, int>();
        private Dictionary<Mesh, int> NormalBuffers { get; set; } = new Dictionary<Mesh, int>();

        public Object3D Model
        {
            get
            {
                return this.obj3d;
            }
        }

        public Renderer(Object3D obj3d)
        {
            this.obj3d = obj3d.ToOneMesh();

            // Set Texture used for faces without texture
            this.emptyTexture = (Bitmap)this.ColorToTexture(Color.LightGray);

            // Set Texture used for lines
            this.lineTexture = (Bitmap)this.ColorToTexture(Color.Black);

            // Set Texture used for lines of selected faces
            this.selectedLineTexture = (Bitmap)this.ColorToTexture(Color.Orange);
        }

        private Image ColorToTexture(Color color)
        {
            var tex = new Bitmap(1, 1);
            tex.SetPixel(0, 0, color);
            return tex;
        }

        /// <summary>
        /// Updates the Data of a Vertex in the buffer.
        /// </summary>
        /// <param name="m">The Mesh where the Vertex is listed.</param>
        /// <param name="v">The Vertex to update.</param>
        public void UpdateVertexData(Mesh m, Vertex v)
        {
            GL.BindBuffer(BufferTarget.ArrayBuffer, this.VertexBuffers[m]);
            var vector = new Vector3((float)v.X, (float)v.Y, (float)v.Z);
            GL.BufferSubData(BufferTarget.ArrayBuffer, (IntPtr)((m.Vertices.IndexOf(v)) * (Vector3.SizeInBytes)), Vector3.SizeInBytes, ref vector);
        }

        /// <summary>
        /// Updates the Data of a Normal in the buffer.
        /// </summary>
        /// <param name="m">The Mesh where the Vertex is listed.</param>
        /// <param name="n">The Normal to update.</param>
        public void UpdateNormalData(Mesh m, Normal n)
        {
            GL.BindBuffer(BufferTarget.ArrayBuffer, this.NormalBuffers[m]);
            var vector = new Vector3((float)n.X, (float)n.Y, (float)n.Z);
            GL.BufferSubData(BufferTarget.ArrayBuffer, (IntPtr)((m.Normals.IndexOf(n)) * (Vector3.SizeInBytes)), Vector3.SizeInBytes, ref vector);
        }

        /// <summary>
        /// Updates the Data of a Vertex Color in the buffer.
        /// </summary>
        /// <param name="m">The Mesh where the Vertex is listed.</param>
        /// <param name="vc">The Vertex Color to update.</param>
        public void UpdateVertexColorData(Mesh m, VertexColor vc)
        {
            GL.BindBuffer(BufferTarget.ArrayBuffer, this.VertexColorBuffers[m]);
            var vector = new Vector4(vc.R, vc.G, vc.B, vc.A);
            GL.BufferSubData(BufferTarget.ArrayBuffer, (IntPtr)((m.VertexColors.IndexOf(vc)) * (Vector4.SizeInBytes)), Vector4.SizeInBytes, ref vector);
        }

        /// <summary>
        /// Updates the Data of a UV in the buffer.
        /// </summary>
        /// <param name="m">The Mesh where the Vertex is listed.</param>
        /// <param name="uv">The UV to update.</param>
        public void UpdateUVData(Mesh m, UV uv)
        {
            GL.BindBuffer(BufferTarget.ArrayBuffer, this.UVBuffers[m]);
            var vector = new Vector2(uv.U, uv.V);
            GL.BufferSubData(BufferTarget.ArrayBuffer, (IntPtr)((m.UVs.IndexOf(uv)) * (Vector2.SizeInBytes)), Vector2.SizeInBytes, ref vector);
        }

        /// <summary>
        /// Updates the indicies of a face in the buffer.
        /// </summary>
        /// <param name="m">The Mesh where the Vertex is listed.</param>
        /// <param name="f">The Face to update.</param>
        public void UpdateFaceIndicies(Mesh m, Face f)
        {
            int faceIndex = m.Faces.IndexOf(f);
            byte uintlen = (byte)Strings.Len(new uint());
            var indicies = new Vector3(m.Vertices.IndexOf(f.Points[0].Vertex), m.Vertices.IndexOf(f.Points[1].Vertex), m.Vertices.IndexOf(f.Points[2].Vertex));
            GL.BindBuffer(BufferTarget.ArrayBuffer, this.IndicesBuffers[m][faceIndex]);
            GL.BufferSubData(BufferTarget.ArrayBuffer, (IntPtr)(uintlen * faceIndex), uintlen, ref indicies);
        }

        /// <summary>
        /// Replace an Image with a new one.
        /// </summary>
        /// <param name="oldImage"></param>
        /// <param name="newImage"></param>
        public void UpdateTexture(Image oldImage, Image newImage)
        {
            if (this.dicTextureIDs.ContainsKey(oldImage))
            {
                int id = this.dicTextureIDs[oldImage];
                this.dicTextureIDs.Remove(oldImage);
                this.dicTextureIDs.Add(newImage, id);
                ContentPipe.LoadTexture((Bitmap)newImage, id);
            }
        }

        /// <summary>
        /// Updates an Image.
        /// </summary>
        /// <param name="image"></param>
        public void UpdateTexture(Image image)
        {
            if (this.dicTextureIDs.ContainsKey(image))
            {
                ContentPipe.LoadTexture(this.dicTextureIDs[image].ToString());
            }
        }

        /// <summary>
        /// Creates the Buffers and store the requied Data.
        /// </summary>
        public void RenderModel()
        {
            this.ReleaseBuffers();
            foreach (Mesh mesh in this.obj3d.Meshes)
            {
                var nibo = new List<int>();
                global::System.Boolean enablecols = ((mesh.VertexColors.Count) > (0));
                global::System.Boolean enablenorms = (((!(enablecols))) && ((mesh.Normals.Count) > (0)));
                var verts = new List<Vector3>();
                var uvs = new List<Vector2>();
                var cols = new List<Vector4>();
                var norms = new List<Vector3>();
                global::System.UInt64 curvi = 0UL;
                this.IndicesBuffers.Add(mesh, nibo);
                for (int i = 0, loopTo = (mesh.Faces.Count) - (1); i <= loopTo; i++)
                {
                    {
                        var withBlock = mesh.Faces[i];
                        var indices = new List<global::System.UInt32>();
                        foreach (Pilz.S3DFileParser.Point p in withBlock.Points)
                        {
                            indices.Add((global::System.UInt32)curvi);
                            curvi = (global::System.UInt64)(curvi + 1m);
                            if (p.Vertex is object)
                            {
                                verts.Add(new Vector3((float)p.Vertex.X, (float)p.Vertex.Y, (float)p.Vertex.Z));
                            }
                            else
                            {
                                verts.Add(new Vector3(0, 0, 0));
                            }

                            if (p.UV is object)
                            {
                                uvs.Add(new Vector2(p.UV.U, p.UV.V));
                            }
                            else
                            {
                                uvs.Add(new Vector2(0, 0));
                            }

                            if (((enablecols) && p.VertexColor is object))
                            {
                                cols.Add(new Vector4(p.VertexColor.R, p.VertexColor.G, p.VertexColor.B, p.VertexColor.A));
                            }
                            else
                            {
                                cols.Add(new Vector4(1, 1, 1, 1));
                            }

                            if (((enablenorms) && p.Normal is object))
                            {
                                norms.Add(new Vector3(p.Normal.X, p.Normal.Y, p.Normal.Z));
                            }
                            else
                            {
                                norms.Add(new Vector3(1, 1, 1));
                            }
                        }

                        nibo.Add(GL.GenBuffer());
                        GL.BindBuffer(BufferTarget.ElementArrayBuffer, nibo[i]);
                        GL.BufferData(BufferTarget.ElementArrayBuffer, (IntPtr)((Strings.Len(new uint())) * (indices.Count)), indices.ToArray(), BufferUsageHint.StaticDraw);
                        if (withBlock.Material?.Image is object)
                        {
                            if (!(this.dicTextureIDs.ContainsKey(withBlock.Material.Image)))
                            {
                                this.dicTextureIDs.Add(withBlock.Material.Image, ContentPipe.LoadTexture((Bitmap)withBlock.Material.Image));
                            }
                        }
                        else if (withBlock.Material?.Color is object)
                        {
                            if (!(this.dicColorIDs.ContainsKey((Color)withBlock.Material.Color)))
                            {
                                this.dicColorIDs.Add((Color)withBlock.Material.Color, ContentPipe.LoadTexture((Bitmap)ColorToTexture((Color)withBlock.Material.Color)));
                            }
                        }
                        else if (!(this.dicTextureIDs.ContainsKey(this.emptyTexture)))
                        {
                            this.dicTextureIDs.Add(this.emptyTexture, ContentPipe.LoadTexture(this.emptyTexture));
                        }
                    }
                }

                int nvbo = GL.GenBuffer();
                this.VertexBuffers.Add(mesh, nvbo);
                GL.BindBuffer(BufferTarget.ArrayBuffer, nvbo);
                GL.BufferData(BufferTarget.ArrayBuffer, (IntPtr)((Vector3.SizeInBytes) * (verts.Count)), verts.ToArray(), BufferUsageHint.StaticDraw);
                int ntbo = GL.GenBuffer();
                this.UVBuffers.Add(mesh, ntbo);
                GL.BindBuffer(BufferTarget.ArrayBuffer, ntbo);
                GL.BufferData(BufferTarget.ArrayBuffer, (IntPtr)((Vector2.SizeInBytes) * (uvs.Count)), uvs.ToArray(), BufferUsageHint.StaticDraw);
                if (enablecols)
                {
                    int ncbo = GL.GenBuffer();
                    this.VertexColorBuffers.Add(mesh, ncbo);
                    GL.BindBuffer(BufferTarget.ArrayBuffer, ncbo);
                    GL.BufferData(BufferTarget.ArrayBuffer, (IntPtr)((Vector4.SizeInBytes) * (cols.Count)), cols.ToArray(), BufferUsageHint.StaticDraw);
                }

                if (enablenorms)
                {
                    int nnbo = GL.GenBuffer();
                    this.NormalBuffers.Add(mesh, nnbo);
                    GL.BindBuffer(BufferTarget.ArrayBuffer, nnbo);
                    GL.BufferData(BufferTarget.ArrayBuffer, (IntPtr)((Vector3.SizeInBytes) * (norms.Count)), norms.ToArray(), BufferUsageHint.StaticDraw);
                }
            }

            if (!(this.dicTextureIDs.ContainsKey(this.lineTexture)))
            {
                this.dicTextureIDs.Add(this.lineTexture, ContentPipe.LoadTexture(this.lineTexture));
            }

            this.HasRendered = true;
        }

        public void DrawModel(RenderMode mode)
        {
            DrawModel(mode, Vector3.Zero, Quaternion.Identity, new Vector3(this.ModelScaling, this.ModelScaling, this.ModelScaling));
        }

        public void DrawModel(RenderMode mode, Vector3 pos, Quaternion rot)
        {
            DrawModel(mode, pos, rot, new Vector3(this.ModelScaling, this.ModelScaling, this.ModelScaling));
        }

        public void DrawModel(RenderMode mode, Vector3 pos, Quaternion rot, Vector3 scale)
        {
            if (((mode) == (RenderMode.None)))
                return;
            if (!(this.HasRendered))
                return;
            GL.PushMatrix();
            GL.Translate(pos.X, pos.Y, pos.Z);
            GL.Rotate(rot.X, 1, 0, 0);
            GL.Rotate(rot.Y, 0, 1, 0);
            GL.Rotate(rot.Z, 0, 0, 1);
            GL.Scale(scale); // GL.Scale(scale.X, scale.Y, scale.Z)
            GL.EnableClientState(ArrayCap.VertexArray);
            GL.EnableClientState(ArrayCap.TextureCoordArray);
            foreach (Mesh mesh in this.obj3d.Meshes)
            {
                if (this.VertexColorBuffers.ContainsKey(mesh))
                {
                    GL.EnableClientState(ArrayCap.ColorArray);
                }
                else if (this.NormalBuffers.ContainsKey(mesh))
                {
                    GL.EnableClientState(ArrayCap.NormalArray);
                }

                GL.BindBuffer(BufferTarget.ArrayBuffer, this.VertexBuffers[mesh]);
                GL.VertexPointer(3, VertexPointerType.Float, 0, IntPtr.Zero);
                GL.BindBuffer(BufferTarget.ArrayBuffer, this.UVBuffers[mesh]);
                GL.TexCoordPointer(2, TexCoordPointerType.Float, 0, IntPtr.Zero);
                if (this.VertexColorBuffers.ContainsKey(mesh))
                {
                    GL.BindBuffer(BufferTarget.ArrayBuffer, this.VertexColorBuffers[mesh]);
                    GL.ColorPointer(4, ColorPointerType.Float, 0, IntPtr.Zero);
                }
                else if (this.NormalBuffers.ContainsKey(mesh))
                {
                    GL.BindBuffer(BufferTarget.ArrayBuffer, this.NormalBuffers[mesh]);
                    GL.NormalPointer(NormalPointerType.Float, 0, IntPtr.Zero);
                }

                for (int i = 0, loopTo = (mesh.Faces.Count) - (1); i <= loopTo; i++)
                {
                    Face l = mesh.Faces[i];
                    GL.BindBuffer(BufferTarget.ElementArrayBuffer, this.IndicesBuffers[mesh][i]);
                    global::System.Boolean isEmptyTexture = l.Material?.Image is null;
                    global::System.Boolean isEmptyColor = l.Material?.Color is null;
                    void setMaterialTextureOrColor()
                    {
                        int texID;
                        if (!(isEmptyTexture))
                        {
                            texID = this.dicTextureIDs[l.Material.Image];
                        }
                        else if (!(isEmptyColor))
                        {
                            texID = this.dicColorIDs[(Color)l.Material.Color];
                        }
                        else
                        {
                            texID = this.dicTextureIDs[this.emptyTexture];
                        }

                        GL.BindTexture(TextureTarget.Texture2D, texID);
                    };
                    if ((((((mode) & (RenderMode.Fill)))) == (RenderMode.Fill)))
                    {
                        setMaterialTextureOrColor();
                        if (!(isEmptyTexture))
                        {
                            GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapT, l.Material.Wrap.X);
                            GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapS, l.Material.Wrap.Y);
                        }

                        GL.PolygonMode(MaterialFace.FrontAndBack, PolygonMode.Fill);
                        GL.DrawElements(PrimitiveType.Triangles, l.Points.Count, DrawElementsType.UnsignedInt, IntPtr.Zero);
                    }

                    if ((((((mode) & (RenderMode.Outline)))) == (RenderMode.Outline)))
                    {
                        if ((((((mode) & (RenderMode.Fill)))) == (RenderMode.Fill)))
                        {
                            GL.BindTexture(TextureTarget.Texture2D, this.dicTextureIDs[this.lineTexture]);
                        }
                        else
                        {
                            setMaterialTextureOrColor();
                            if (!(isEmptyTexture))
                            {
                                GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapT, l.Material.Wrap.X);
                                GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapS, l.Material.Wrap.Y);
                            }
                        }

                        GL.PolygonMode(MaterialFace.FrontAndBack, PolygonMode.Line);
                        GL.DrawElements(PrimitiveType.Triangles, l.Points.Count, DrawElementsType.UnsignedInt, IntPtr.Zero);
                    }
                }

                GL.PolygonMode(MaterialFace.FrontAndBack, PolygonMode.Fill); // Reset for RenderEngineOld
                if (this.VertexColorBuffers.ContainsKey(mesh))
                {
                    GL.DisableClientState(ArrayCap.ColorArray);
                }
                else if (this.NormalBuffers.ContainsKey(mesh))
                {
                    GL.DisableClientState(ArrayCap.NormalArray);
                }
            }

            GL.DisableClientState(ArrayCap.VertexArray);
            GL.DisableClientState(ArrayCap.TextureCoordArray);
            GL.PopMatrix();
        }

        public void DrawFacePicking()
        {
            DrawFacePicking(Vector3.Zero, Quaternion.Identity, new Vector3(this.ModelScaling, this.ModelScaling, this.ModelScaling));
        }

        public void DrawFacePicking(Vector3 pos, Quaternion rot)
        {
            DrawFacePicking(pos, rot, new Vector3(this.ModelScaling, this.ModelScaling, this.ModelScaling));
        }

        public void DrawFacePicking(Vector3 pos, Quaternion rot, Vector3 scale)
        {
            if (!(this.HasRendered))
                return;
            GL.PushMatrix();
            GL.Translate(pos.X, pos.Y, pos.Z);
            GL.Rotate(rot.X, 1, 0, 0);
            GL.Rotate(rot.Y, 0, 1, 0);
            GL.Rotate(rot.Z, 0, 0, 1);
            GL.Scale(scale);
            GL.EnableClientState(ArrayCap.VertexArray);
            for (int iMesh = 0, loopTo = (this.obj3d.Meshes.Count) - (1); iMesh <= loopTo; iMesh++)
            {
                Mesh mesh = this.obj3d.Meshes[iMesh];
                GL.BindBuffer(BufferTarget.ArrayBuffer, this.VertexBuffers[mesh]);
                GL.VertexPointer(3, VertexPointerType.Float, 0, IntPtr.Zero);
                for (int iFace = 0, loopTo1 = (mesh.Faces.Count) - (1); iFace <= loopTo1; iFace++)
                {
                    Face l = mesh.Faces[iFace];
                    GL.BindBuffer(BufferTarget.ElementArrayBuffer, this.IndicesBuffers[mesh][iFace]);
                    int colorCode = (((0x20000000) + ((((iMesh) << (16))))) + (iFace));
                    GL.Color4(Color.FromArgb(colorCode)); // Color: "2f ff xx xx" -> where 'f' = mesh index and where 'x' is face index
                    GL.PolygonMode(MaterialFace.FrontAndBack, PolygonMode.Fill);
                    GL.DrawElements(PrimitiveType.Triangles, l.Points.Count, DrawElementsType.UnsignedInt, IntPtr.Zero);
                }

                GL.PolygonMode(MaterialFace.FrontAndBack, PolygonMode.Fill);
            }

            GL.DisableClientState(ArrayCap.VertexArray);
            GL.PopMatrix();
        }

        public void ReleaseBuffers()
        {
            if (!(this.HasRendered))
                return;
            foreach (KeyValuePair<Mesh, int> kvp in this.VertexBuffers)
                GL.DeleteBuffer(kvp.Value);
            this.VertexBuffers.Clear();
            foreach (KeyValuePair<Mesh, int> kvp in this.UVBuffers)
                GL.DeleteBuffer(kvp.Value);
            this.UVBuffers.Clear();
            foreach (KeyValuePair<Mesh, int> kvp in this.VertexColorBuffers)
                GL.DeleteBuffer(kvp.Value);
            this.VertexColorBuffers.Clear();
            foreach (KeyValuePair<Mesh, int> kvp in this.NormalBuffers)
                GL.DeleteBuffer(kvp.Value);
            this.NormalBuffers.Clear();
            foreach (KeyValuePair<Mesh, List<int>> kvp in this.IndicesBuffers)
            {
                foreach (int i in kvp.Value)
                    GL.DeleteBuffer(i);
                kvp.Value.Clear();
            }

            this.IndicesBuffers.Clear();
            foreach (KeyValuePair<Image, int> kvp in this.dicTextureIDs)
                GL.DeleteBuffer(kvp.Value);
            this.dicTextureIDs.Clear();
            foreach (KeyValuePair<Color, int> kvp in this.dicColorIDs)
                GL.DeleteBuffer(kvp.Value);
            this.dicColorIDs.Clear();
            this.HasRendered = false;
        }

        ~Renderer()
        {
            // ReleaseBuffers()
        }
    }
}