using StgSharp.Geometries;
using StgSharp.Graphics;
using StgSharp.Math;
using StgSharp.Math.Linear;
using System;
using System.Diagnostics;
using System.IO;
using System.Numerics;
using System.Runtime.InteropServices;
using System.Text;

namespace StgSharp
{

    internal static class Program
    {

        internal unsafe static void DebugMain(string[] args)
        {

            InternalIO.InternalWriteLog("\n\n\n", "Program start", LogType.Info);
            InternalIO.InternalWriteLog($"{typeof(vec3d).Name}", LogType.Info);
            Graphic.InitGL(4, 6);

            //GL.glfw->WindowHint(GLFW.GLFW_DECORATED, GLFW.GL_FALSE);
            //Form f = Graphic.CreateWindow(800, 600, "Test STG#!", IntPtr.Zero, null);
            Form f = new Form(800, 600, "Hello,STG#!", IntPtr.Zero, null);
            f.MakeAsCurrentContext();
            f.SetSizeLimit(800, 600, 800, 600);
            GL.SetFrameBufferSizeCallback(f, FormSizeCallback);

            f.LoadGlapi(GL.LoadGLfunc);

            Shader shader = new Shader();
            shader.CompileVertexShader(
                File.ReadAllText("Shader\\vertex.vert")
                );
            shader.CompileFragmentShader(
                File.ReadAllText("Shader\\fragment.frag")
                );
            shader.Link();


            Triangle tri = new Triangle(
                -0.5f, -0.3f, 0.0f,
                0.5f, -0.5f, 0.0f,
                0.0f, 0.5f, 0.0f
                );

            Rectangle rec = new Rectangle(
                -0.4f, 0.5f, 0.0f,
                0.5f, 0.5f, 0.0f,
                0.6f, -0.5f, 0.0f,
                -0.7f, -0.5f, 0.0f
                );

            Polygon5 polygon = new Polygon5(
                -0.4f, 0.5f, 0.0f,
                0.5f, 0.5f, 0.0f,
                0.6f, -0.5f, 0.0f,
                0, -1, 0,
                -0.7f, -0.5f, 0.0f
                );


            VertexArray vao = new VertexArray(1);
            VertexBuffer vbo = new VertexBuffer(1);
            ElementBuffer ebo = new ElementBuffer(1);

            GL.glBindVertexArray(vao[0]);



            vbo.SetData(0, polygon.VertexBuffer, BufferUsage.STATIC_DRAW);
            ebo.SetData(0, polygon.Indices, BufferUsage.STATIC_DRAW);



            GL.glVertexAttribPointer(0, 3, GLconst.FLOAT, false, 4 * sizeof(float), (void*)0);
            GL.glEnableVertexAttribArray(0);


            /**/
            GL.glBindBuffer(GLconst.ARRAY_BUFFER, 0);
            GL.glBindVertexArray(0);
            /**/



            while (InternalIO.glfw_WindowShouldClose(f.windowID) == 0)
            {
                ProcessInput(f.windowID);

                GL.ClearColor(0.2f, 0.3f, 0.3f, 1.0f);
                GL.glClear(GLconst.COLOR_BUFFER_BIT);

                shader.Use();

                GL.glBindVertexArray(vao._bufferID[0]);

                GL.DrawElements(GepmetryType.TRIANGLES, 9, typeof(uint), IntPtr.Zero);

                GL.glBindVertexArray(0);

                InternalIO.glfw_SwapBuffers(f.windowID);
                InternalIO.glfw_PollEvents();
                InternalIO.glfw_PollEvents();
            }

            /**/
            vao.Dispose();
            vbo.Dispose();
            ebo.Dispose();
            /**/

            /*
            Graphic.glDeleteVertexArrays(1, &vao);
            Graphic.glDeleteBuffers(1, &vao);
            Graphic.glDeleteBuffers(1, &vao);
            /**/

            InternalIO.glfw_Terminate();
        }

        internal unsafe static void Main(string[] args)
        {
            try
            {
                DebugMain(args);
            }
            catch (Exception ex)
            {
                InternalIO.InternalWriteLog(
                    ex.Message + "\n" + ex.StackTrace,
                    LogType.Error);
            }
        }

        public static unsafe void FormSizeCallback(IntPtr window, int width, int height)
        {
            GL.glViewport(0, 0, width, height);
        }

        public static unsafe void ProcessInput(IntPtr windowPtr)
        {
            if (InternalIO.glfw_GetKey(windowPtr, (int)Control.Key.ESCAPE)
                == KeyStatus.PRESS)
            {
                InternalIO.glfw_SetWindowShouldClose(windowPtr, 1);
            }
        }

        [DllImport(InternalIO.SSGC_libname, EntryPoint = "printShaderCode",
            CallingConvention = CallingConvention.Cdecl)]
        internal extern unsafe static void PrintShader(byte** shadercode);


    }
}