using System;
using System.Runtime.InteropServices;

using Iisu;
using MathNet.Numerics.LinearAlgebra.Single;

namespace bbiwarg
{
    class IIsuDataSource: IVideoDataSource
    {
        private IHandle handle;
        private IDevice device;
        private string moviePath;
        bool active;

        // parameters
        private IParameterHandle<float> frameRate;

        // data
        private IDataHandle<bool>[] handOpen = new IDataHandle<bool>[2];
        private IDataHandle<Iisu.Data.Vector3>[] palmPositions3D = new IDataHandle<Iisu.Data.Vector3>[2];
        private IDataHandle<Iisu.Data.Vector3>[] tipPositions3D = new IDataHandle<Iisu.Data.Vector3>[2];
        private IDataHandle<Iisu.Data.Vector3>[] forearmPositions3D = new IDataHandle<Iisu.Data.Vector3>[2];
        private IDataHandle<Iisu.Data.Vector3>[] palmNormals3D = new IDataHandle<Iisu.Data.Vector3>[2];
        private IDataHandle<int[]>[] fingerStatus = new IDataHandle<int[]>[2];
        private IDataHandle<Iisu.Data.Vector3[]>[] fingerTipPositions3D = new IDataHandle<Iisu.Data.Vector3[]>[2];
        private IDataHandle<int>[] handSides = new IDataHandle<int>[2];
        private IDataHandle<Iisu.Data.IImageData> depthImage;

        /*
         * Creates an Iisu data source.
         * params:
         *  moviePath: path to movie to be used as source
         *             if empty the camera is used
         */
        public IIsuDataSource(string moviePath = "")
        {
            this.moviePath = moviePath;
            active = false;
        }

        public void init()
        {
            handle = Iisu.Iisu.Context.CreateHandle();
            
            IDeviceConfiguration conf = handle.CreateDeviceConfiguration();
            if (moviePath.Length != 0)
                conf.MoviePath = moviePath;
            
            device = handle.InitializeDevice(conf);
            
            // parameters
            device.RegisterParameterHandle<int>("SOURCE.MOVIE.PlayMode").Value = 0; // playMode = once
            frameRate = device.RegisterParameterHandle<float>("SOURCE.FrameRate"); 

            // events
            device.EventManager.RegisterEventListener("DEVICE.Status", new Iisu.EventDelegates.Device.Status(onDeviceStatusChanged));
            
            // data
            depthImage = device.RegisterDataHandle<Iisu.Data.IImageData>("SOURCE.CAMERA.DEPTH.Image");
            
            handOpen[0] = device.RegisterDataHandle<bool>("CI.HAND1.IsOpen");
            handOpen[1] = device.RegisterDataHandle<bool>("CI.HAND2.IsOpen");

            palmPositions3D[0] = device.RegisterDataHandle<Iisu.Data.Vector3>("CI.HAND1.PalmPosition3D");
            palmPositions3D[1] = device.RegisterDataHandle<Iisu.Data.Vector3>("CI.HAND2.PalmPosition3D");

            tipPositions3D[0] = device.RegisterDataHandle<Iisu.Data.Vector3>("CI.HAND1.TipPosition3D");
            tipPositions3D[1] = device.RegisterDataHandle<Iisu.Data.Vector3>("CI.HAND2.TipPosition3D");

            forearmPositions3D[0] = device.RegisterDataHandle<Iisu.Data.Vector3>("CI.HAND1.ForearmPosition3D");
            forearmPositions3D[1] = device.RegisterDataHandle<Iisu.Data.Vector3>("CI.HAND2.ForearmPosition3D");

            palmNormals3D[0] = device.RegisterDataHandle<Iisu.Data.Vector3>("CI.HAND1.PalmNormal3D");
            palmNormals3D[1] = device.RegisterDataHandle<Iisu.Data.Vector3>("CI.HAND2.PalmNormal3D");

            fingerStatus[0] = device.RegisterDataHandle<int[]>("CI.HAND1.FingerStatus");
            fingerStatus[1] = device.RegisterDataHandle<int[]>("CI.HAND2.FingerStatus");

            fingerTipPositions3D[0] = device.RegisterDataHandle<Iisu.Data.Vector3[]>("CI.HAND1.FingerTipPositions3D");
            fingerTipPositions3D[1] = device.RegisterDataHandle<Iisu.Data.Vector3[]>("CI.HAND2.FingerTipPositions3D");

            handSides[0] = device.RegisterDataHandle<int>("CI.HAND1.Side");
            handSides[1] = device.RegisterDataHandle<int>("CI.HAND1.Side");
        }

        private void onDeviceStatusChanged(string eventName, DeviceStatus status)
        {
            active = status.HasFlag(Iisu.DeviceStatus.Playing);
        }

        public void start()
        {
            device.Start();
        }

        public void stop()
        {
            device.Stop(true);
        }

        public void updateFrame()
        {
            device.UpdateFrame(true);
        }

        public void releaseFrame()
        {
            device.ReleaseFrame();
        }

        public bool isActive()
        {
            return active;
        }

        public int getFrameRate()
        {
            return (int) frameRate.Value;
        }

        public DepthImage getDepthImage()
        {
            Iisu.Data.IImageInfos imageInfos = depthImage.Value.ImageInfos;
            int width = (int) imageInfos.Width;
            int height = (int) imageInfos.Height;
            int numBytes = (int) imageInfos.BytesRaw;

            IntPtr imageData = depthImage.Value.Raw;
            
            short[] tmp = new short[width * height];
            Marshal.Copy(imageData, tmp, 0, width * height);

            ushort[] data = new ushort[width * height];
            Buffer.BlockCopy(tmp, 0, data, 0, numBytes);

            return new DepthImage(width, height, data);
        }

        private void checkHandIndex(uint handIndex) 
        {
            if (handIndex < 1 || handIndex > 2)
                throw new ArgumentOutOfRangeException("handIndex is out of range [0,1]");
        }

        public bool isHandOpen(uint handIndex)
        {
            checkHandIndex(handIndex);
            return handOpen[handIndex - 1].Value;
        }

        public Vector getPalmPosition3D(uint handIndex)
        {
            checkHandIndex(handIndex);
            return new DenseVector(palmPositions3D[handIndex - 1].Value.ToArray());
        }

        public Vector getTipPosition3D(uint handIndex)
        {
            checkHandIndex(handIndex);
            return new DenseVector(tipPositions3D[handIndex - 1].Value.ToArray());
        }

        public Vector getForearmPosition3D(uint handIndex)
        {
            checkHandIndex(handIndex);
            return new DenseVector(forearmPositions3D[handIndex - 1].Value.ToArray());
        }

        public Vector getPalmNormal3D(uint handIndex)
        {
            checkHandIndex(handIndex);
            return new DenseVector(palmNormals3D[handIndex - 1].Value.ToArray());
        }

        public FingerStatus[] getFingerStatus(uint handIndex)
        {
            checkHandIndex(handIndex);
            int[] status = fingerStatus[handIndex - 1].Value;
            FingerStatus[] result = new FingerStatus[status.Length];
            for (int i = 0; i < status.Length; ++i)
            {
                switch (status[i])
                {
                    case 0:
                        result[i] = FingerStatus.Inactive;
                        break;
                    case 1:
                        result[i] = FingerStatus.Detected;
                        break;
                    case 2:
                        result[i] = FingerStatus.Tracked;
                        break;
                }
            }
            return result;
        }

        public Vector[] getFingerTipPositions3D(uint handIndex)
        {
            checkHandIndex(handIndex);
            Iisu.Data.Vector3[] positions = fingerTipPositions3D[handIndex - 1].Value;
            Vector[] results = new DenseVector[positions.Length];
            for (int i = 0; i < positions.Length; ++i)
                results[i] = new DenseVector(positions[i].ToArray());
            return results;
        }

        public HandSide getHandSide(uint handIndex)
        {
            checkHandIndex(handIndex);
            int side = handSides[handIndex - 1].Value;
            switch (side) 
            {
                case 1:
                    return HandSide.Left;
                case 2:
                    return HandSide.Right;
                default:
                    return HandSide.Unknown;
            }
        }
    }
}