using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using OpenTK;
using OpenTK.Graphics.OpenGL;
using MathNet.Numerics.LinearAlgebra.Single;
using bbiwarg.DataSource;


namespace bbiwarg.Graphics
{
    class Output : GameWindow
    {
        private IVideoHandle videoHandle;

        private uint imageBufferId;

        public Output(IVideoHandle videoHandle)
        {
            this.videoHandle = videoHandle;
        }

        protected override void OnLoad(EventArgs e)
        {
            base.OnLoad(e);
            Title = "OutputTest";
            GL.ClearColor(Color.Black);

            // transparency
            GL.Enable(EnableCap.Blend);
            GL.BlendEquation(BlendEquationMode.Max);

            initBuffers();
        }

        protected override void OnRenderFrame(FrameEventArgs e)
        {
            base.OnRenderFrame(e);
            GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit);
            Matrix4 modelview = Matrix4.LookAt(Vector3.Zero, -Vector3.UnitZ, Vector3.UnitY);
            GL.MatrixMode(MatrixMode.Modelview);
            GL.LoadMatrix(ref modelview);

            videoHandle.nextFrame();

            Stopwatch sw = new Stopwatch();
            sw.Start();

            drawDepthImage();

            // palm (iisu)
            Vector palmPosition = videoHandle.getPalmPosition3D(1);
            Point palmPoint = new Point(palmPosition, Color.Yellow, 0.005f);
            palmPoint.draw();

            // foreFinger
            Vector foreFingerPosition = videoHandle.getForeFingerPosition3D(1);
            Point foreFingerPoint = new Point(foreFingerPosition, Color.Red, 0.005f);
            foreFingerPoint.draw();

            // foreArm (iisu)
            Vector foreArmPosition = videoHandle.getForearmPosition3D(1);
            Point foreArmPoint = new Point(foreArmPosition, Color.Yellow, 0.005f);
            foreArmPoint.draw();

            // finger (iisu)
            Vector[] fingerPositions = videoHandle.getFingerTipPositions3D(1);
            DetectionStatus[] fingerStatus = videoHandle.getFingerStatus(1);
            for (int i = 0; i < fingerStatus.Length; ++i)
            {
                if (fingerStatus[i] == DetectionStatus.Detected || fingerStatus[i] == DetectionStatus.Tracked)
                {
                    Point fingerPoint = new Point(fingerPositions[i], Color.Yellow, 0.005f);
                    fingerPoint.draw();
                }
            }

            // palm
            Palm palm = videoHandle.getPalm(1);
            Rectangle palmRect = new Rectangle(palm.getCorners(), Color.FromArgb(128, Color.Blue));
            palmRect.draw();

            sw.Stop();
            Console.WriteLine(sw.ElapsedMilliseconds);

            SwapBuffers();
        }

        protected override void OnResize(EventArgs e)
        {
            base.OnResize(e);
            GL.Viewport(ClientRectangle.X, ClientRectangle.Y, ClientRectangle.Width, ClientRectangle.Height);
            Matrix4 projection = Matrix4.CreatePerspectiveFieldOfView((float)Math.PI / 3, Width / (float)Height, 0.01f, 3.0f);
            GL.MatrixMode(MatrixMode.Projection);
            GL.LoadMatrix(ref projection);
        }

        private void initBuffers()
        {
            GL.GenBuffers(1, out imageBufferId);

            GL.BindBuffer(BufferTarget.ArrayBuffer, imageBufferId);
            GL.BufferData(BufferTarget.ArrayBuffer, 
                          (IntPtr)((3 * sizeof(float) + 4  * sizeof(byte)) * videoHandle.getWidth() * videoHandle.getHeight()), 
                          IntPtr.Zero, BufferUsageHint.StreamDraw);
        }

        private void drawDepthImage()
        {
            GL.EnableClientState(ArrayCap.VertexArray);
            GL.EnableClientState(ArrayCap.ColorArray);

            GL.BindBuffer(BufferTarget.ArrayBuffer, imageBufferId);
            videoHandle.createVertexArray(GL.MapBuffer(BufferTarget.ArrayBuffer, BufferAccess.WriteOnly));
            GL.UnmapBuffer(BufferTarget.ArrayBuffer);

            GL.VertexPointer(3, VertexPointerType.Float, 3 * sizeof(float) + 4 * sizeof(byte), IntPtr.Zero);
            GL.ColorPointer(4, ColorPointerType.UnsignedByte, 3 * sizeof(float) + 4 * sizeof(byte), 3 * sizeof(float));

            GL.PointSize(2.0f);
            GL.DrawArrays(PrimitiveType.Points, 0, videoHandle.getWidth() * videoHandle.getHeight());
           
        }
    }
}