using System;
using System.Collections.Generic;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Emgu.CV;
using Emgu.CV.Structure;

namespace bbiwarg.Images
{
    class DepthImage
    {
        public Image<Gray, Int16> Image { get; private set; }
        public int Width { get { return Image.Width; } }
        public int Height { get { return Image.Height; } }
        public Int16 MinDepth { get; private set; }
        public Int16 MaxDepth { get; private set; }

        public DepthImage(Image<Gray, Int16> image)
        {
            this.Image = image;

            //smooth
            this.Image = image.SmoothMedian(3);

            //threshold min&maxDepth
            MinDepth = findMinDepth();
            MaxDepth = (Int16)(MinDepth + 200);
            thresholdDepth(MinDepth, MaxDepth);

        }

        public Int16 getDepthAt(Point point)
        {
            return getDepthAt(point.X, point.Y);
        }

        public Int16 getDepthAt(int x, int y)
        {
            return Image.Data[y, x, 0];
        }

        public void setDepthAt(Point point, Int16 depth)
        {
            setDepthAt(point.X, point.Y, depth);
        }

        public void setDepthAt(int x, int y, Int16 depth)
        {
            Image.Data[y, x, 0] = depth;
        }

        public float getRelativeDepthAt(Point point)
        {
            return getRelativeDepthAt(point.X, point.Y);
        }

        public float getRelativeDepthAt(int x, int y)
        {
            float minMaxInterval = Math.Max(MaxDepth - MinDepth, 1);
            return (getDepthAt(x, y) - MinDepth) / minMaxInterval;
        }

        public Int16 getMinDepth()
        {
            return MinDepth;
        }

        public Int16 getMaxDepth()
        {
            return MaxDepth;
        }

        private Int16 findMinDepth()
        {
            MinDepth = Int16.MaxValue;
            for (int x = 0; x < Width; ++x)
            {
                for (int y = 0; y < Height; ++y)
                {
                    Int16 depth = getDepthAt(x, y);
                    if (depth < MinDepth)
                        MinDepth = depth;
                }
            }
            return MinDepth;
        }

        private void thresholdDepth(Int16 min, Int16 max)
        {
            for (int x = 0; x < Width; ++x)
            {
                for (int y = 0; y < Height; ++y)
                {
                    Int16 depth = getDepthAt(x, y);
                    if (depth > max || depth < min)
                        setDepthAt(x, y, max);
                }
            }
        }
    }
}