//-----------------------------------------------------------------------
//-----------------------------------------------------------------------
//     file="Particle.cs"
//     Project: StgSharp
//     AuthorGroup: Nitload Space
//     Copyright (c) Nitload Space. All rights reserved.
//     
//     Permission is hereby granted, free of charge, to any person 
//     obtaining a copy of this software and associated documentation 
//     files (the “Software”), to deal in the Software without restriction, 
//     including without limitation the rights to use, copy, modify, merge,
//     publish, distribute, sublicense, and/or sell copies of the Software, 
//     and to permit persons to whom the Software is furnished to do so, 
//     subject to the following conditions:
//     
//     The above copyright notice and 
//     this permission notice shall be included in all copies 
//     or substantial portions of the Software.
//     
//     THE SOFTWARE IS PROVIDED “AS IS”, 
//     WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, 
//     INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
//     FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. 
//     IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 
//     DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 
//     ARISING FROM, OUT OF OR IN CONNECTION WITH 
//     THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//     
//-----------------------------------------------------------------------
//-----------------------------------------------------------------------
using StgSharp.Geometries;
using StgSharp.Graphics;
using StgSharp.Graphics.GL;
using StgSharp.Logic;
using StgSharp.Math;

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Text;
using System.Threading.Channels;
using System.Threading.Tasks;

namespace StgSharp
{
    public class ParticleStream : glRenderStream
    {

        ElementBuffer ebo;

        FrameBuffer fbo;
        Image i;
        PlainInstancingBuffer<ParticleOnPlain> buffer;
        RenderBuffer rbo;

        ShaderProgram s;

        TextureGL t;
        VertexArray vao;
        VertexBuffer vbo;

        public ParticleStream(ViewPort args, (int, int, int) cube) : base(args, (100, 100, 100))
        {
        }

        protected override string[] InputPortsName => ["input_1"];

        protected override string[] OutputPortsName => ["output_1"];

        internal static vec3d DefaultRotation(TimeSpanProvider provider, out float rotation)
        {
            rotation = 0.1f;
            float angle = provider.CurrentSpan * 0.1f;
            return new vec3d(
                0.01f * Scaler.Cos(angle),
                (-0.01f) * Scaler.Sin(angle),
                0
                );
        }

        protected override void Deinit()
        {
            throw new NotImplementedException();
        }

        protected override void Init()
        {
            buffer = new PlainInstancingBuffer<ParticleOnPlain>();
            for (int i = 0; i < 10; i++)
            {
                float ai = Scaler.Abs(i - 5.0f);
                for (int t = 0; t < 10; t++)
                {
                    float at = Scaler.Abs(t - 5.0f);

                    ParticleOnPlain p = new ParticleOnPlain(buffer);
                    ((IInstancing)p).Coord = new vec3d(
                        (((-5) + i) * 0.2f) + 0.1f, (((-5) + t) * 0.2f) + 0.1f, 0);
                    ((IInstancing)p).Scale =
                        Scaler.MinOf(i, t) * 0.15f;
                    ((IInstancing)p).Motion = new GeometryMotion(
                        true, this.timeProvider,
                        DefaultRotation)
                        ;
                }
            }

            //SetSizeLimit(800, 800, 800, 800);

            FrameSizeCallback =
                (IntPtr id, uint width, uint height) => glFunc.Viewport(0, 0, width, height);

            s = CreateShaderProgram();
            Shader pvs = CreateShaderSegment(ShaderType.Vertex, 1);
            Shader pfs = CreateShaderSegment(ShaderType.Fragment, 1);

            pvs.Compile(0, Shader.FromCodeFile("Shader\\particle.vert"));
            pvs.AttachTo(0, s);
            pfs.Compile(0, Shader.FromCodeFile("Shader\\particle.frag"));
            pfs.AttachTo(0, s);
            s.Link();

            vbo = CreateVertexBuffer(3);
            vao = CreateVertexArray(1);
            ebo = CreateElementBuffer(1);
            vbo.Bind(0);

            Rectangle rec = new Rectangle
                (
                0.05f, 0.05f,
                0.05f, -0.05f,
                -0.05f, -0.05f,
                -0.05f, 0.05f
                );

            vao.Bind(0);
            vbo.WriteVectorData(0, rec.VertexStream, BufferUsage.StaticDraw);
            ebo.SetValue(0, rec.VertexIndices, BufferUsage.StaticDraw);
            VertexArray.SetVertexAttribute(0, 3, TypeCode.Single, false, 4 * sizeof(float), 0);

            vbo.WriteVectorData<vec4d>(1, buffer.CoordAndRotationSpan, BufferUsage.StreamDraw);
            VertexArray.SetVertexAttribute(1, 3, TypeCode.Single, false, 4 * sizeof(float), 0);
            VertexArray.SetVertexAttribute(2, 1, TypeCode.Single, false, 4 * sizeof(float), 3 * sizeof(float));

            glFunc.VertexAttributeDivisor(1, 1);
            glFunc.VertexAttributeDivisor(2, 1);

            vbo.WriteScalerData<float>(2, buffer.ScalingSpan, BufferUsage.StaticDraw);
            VertexArray.SetVertexAttribute(3, 1, TypeCode.Single, false, sizeof(float), 0);

            glFunc.VertexAttributeDivisor(3, 1);



            vbo.Unbind();
            VertexArray.BindNull();

            NativeCameraViewTarget
                (
                (0, 0, -100),
                (0, 0, 0),
                (0, 1, 0)
                );
            NativeCameraViewRange(new Degree(1.5f), Vec2d.Zero, (50, 50));
            NativeCameraUniform(s, "Camera");

            s.Use();
            fbo = CreateFrameBuffer(1);
            rbo = CreateRenderBuffer(1);

            fbo.Bind(0);
            rbo.Bind(0);
            glFunc.SetRenderBufferStorage(
                RenderBufferInternalFormat.Depth24_Stencil8, this.Size);


            t = CreateTexture(1);
            t.Bind2D(0);
            /**/
            glFunc.TextureImage2d(Texture2DTarget.Texture2D, 0, (int)ImageChannel.WithAlphaChannel,
                (uint)Width, (uint)Height, (int)ImageChannel.WithAlphaChannel, ImageChannelLayout.Byte, glHandle.ZeroHandle);
            /**/
            t.Set2dWrapProperty(Wrap.Repeat, Wrap.Repeat);
            t.Set2dFilterProperty(Filter.Nearest, Filter.Nearest);


            glFunc.FrameBufferTexture2d(FrameBufferTarget.All, glAttachment.Color(0),
        Texture2DTarget.Texture2D, t[0], 0);

            glFunc.CombineFrameBufferRenderBuffer(fbo[0], rbo[0]);

            int streamLength = this.Width * this.Height * 4;
            byte[] imageStream = new byte[streamLength];
            i = Image.FromMemory(this.Size, 4, imageStream);
        }

        protected override void Main(
            in Dictionary<string, BlueprintPipeline> input,
            in Dictionary<string, BlueprintPipeline> output)
        {
            //Console.WriteLine($"{Width} {Height}");
            buffer.UpdateAllParticles();

            fbo.Bind(0);
            vao.Bind(0);
            t.Bind2D(0);
            /**/
            glFunc.TextureImage2d(Texture2DTarget.Texture2D, 0, (int)ImageChannel.WithAlphaChannel,
                (uint)Width, (uint)Height, (int)ImageChannel.WithAlphaChannel, ImageChannelLayout.Byte, glHandle.ZeroHandle);
            /**/

            glFunc.ClearColor(0.6f, 0.1f, 0.3f, 1);
            glFunc.Clear(MaskBufferBit.COLOR | MaskBufferBit.DEPTH);

            vbo.Bind(1);
            vbo.WriteVectorData<vec4d>(1, buffer.CoordAndRotationSpan, BufferUsage.StreamDraw);

            s.Use();
            NativeCamera.SetAllUniforms();

            glFunc.DrawElementsInstanced(
                GeometryType.TRIANGLES, 6, TypeCode.UInt32, IntPtr.Zero, 100
                );
            glFunc.WaitAccomplishment();
            VertexArray.BindNull();

            /**/

            ImageProcessor.Resize(i, this.Width, this.Height, ImageMovement.Discard);

            glFunc.GetTextureImage(Texture2DTarget.Texture2D, 0, ImageChannel.WithAlphaChannel,
                ImageChannelLayout.Byte, ref i.data);

            //Array.Fill<byte>(i.DataStream, 24);
            output["output_1"].CompleteAndWriteData(new TexturePipeline(i));
            FrameBuffer.BindNull();
            /**/

            /*
            //BlueprintPipeline.SkipAll(output);
            SwapBuffers();
            PollEvents();
            /**/
        }

    }
}