using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using System.Threading;
using System.Web;
using System.Net;
using System.IO;
using System.Drawing;


namespace GICPropertyInfo.Controllers
{
    [Route("api/[controller]")]
    [ApiController]
    public class staticMapController : ControllerBase
    {
        TileImage[] tileImages;
        public int tileSizeInPixels = 256;

        public MemoryStream Get()
        {
            //Get URL parameters
            double cntrLatitude = double.Parse(HttpUtility.ParseQueryString(Request.QueryString.ToString()).Get("latitude"));
            double cntrLongitude = double.Parse(HttpUtility.ParseQueryString(Request.QueryString.ToString()).Get("longitude"));

            string vexcelToken = HttpUtility.ParseQueryString(Request.QueryString.ToString()).Get("authtoken");
            if (vexcelToken==null || vexcelToken=="")
                return new System.IO.MemoryStream(System.Text.Encoding.UTF8.GetBytes("authtoken is a required parameter."));

            int zoom;
            string tmpZoom = HttpUtility.ParseQueryString(Request.QueryString.ToString()).Get("zoom");
            if (tmpZoom == null || tmpZoom == "")
                zoom = 21;
            else
                zoom = int.Parse(tmpZoom);

            int widthInPixels;
            string tmpWidth = HttpUtility.ParseQueryString(Request.QueryString.ToString()).Get("width");
            if (tmpWidth == null || tmpWidth == "")
                widthInPixels = 400;
            else
                widthInPixels = int.Parse(tmpWidth);

            int heightInPixels;
            string tmpHeight = HttpUtility.ParseQueryString(Request.QueryString.ToString()).Get("height");
            if (tmpHeight == null || tmpHeight == "")
                heightInPixels = 400;
            else
                heightInPixels = int.Parse(tmpHeight);

            string layername = HttpUtility.ParseQueryString(Request.QueryString.ToString()).Get("layer");
            if (layername ==null || layername=="")
                layername = "bluesky-ultra";

            string aoiName = HttpUtility.ParseQueryString(Request.QueryString.ToString()).Get("aoi");
            if (aoiName == null || aoiName == "")
                aoiName = "";

            string wktpolygon = HttpUtility.ParseQueryString(Request.QueryString.ToString()).Get("wkt");
            if (wktpolygon == null || wktpolygon == "")
                wktpolygon = "";
         
            string wktAction = HttpUtility.ParseQueryString(Request.QueryString.ToString()).Get("wktaction");
            if (wktAction == null || wktAction == "")
                wktAction = "draw";

            //Calculate the pixel dimension bounding box
            TileSystem.LatLongToPixelXY(cntrLatitude, cntrLongitude, zoom, out int pixelX, out int pixelY);

            int minPixelX = pixelX - (widthInPixels / 2);
            int maxPixelX = pixelX + (widthInPixels / 2);

            int minPixelY = pixelY - (heightInPixels / 2);
            int maxPixelY = pixelY + (heightInPixels / 2);
            
            //calculate the tiles needed to cover that bounding box
            TileSystem.PixelXYToTileXY(minPixelX, minPixelY, out int minTileX, out int minTileY);
            TileSystem.PixelXYToTileXY(maxPixelX, maxPixelY, out int maxTileX, out int maxTileY);

            //Get the Pixel location of the Upper Left Tile
            TileSystem.TileXYToPixelXY(minTileX, minTileY, out int PixelXorigin, out int PixelYorigin);

            //build an image from all the tiles
            Image imgUncropped = getPropertyTiles(minTileX, maxTileX- minTileX+1, minTileY, maxTileY - minTileY + 1, 
                zoom, vexcelToken, layername,aoiName);

            //If a polygon was passed in, this is the place to apply it...
            //Either Draw it...
            if (wktpolygon!="" && wktAction=="draw")
            {
                List<Coordinate> polygonCoordsLatLong = UtilityFunctions.convertWKTPolygonToCoordinates(wktpolygon);

                imgUncropped = renderPolygonToBitmap(polygonCoordsLatLong, PixelXorigin, PixelYorigin, zoom,
                    imgUncropped, Color.Red, Color.Yellow);
            }

            //or Crop with it
            if (wktpolygon != "" && wktAction == "crop")
            {
                List<Coordinate> polygonCoordsLatLong = UtilityFunctions.convertWKTPolygonToCoordinates(wktpolygon);

                //Convert the polygon's lat/long coordinates to pixel coordinates
                PointF[] polygonPixels = new PointF[polygonCoordsLatLong.Count];
                PointF thisPointPixel = new PointF();

                for (int thiscoord = 0; thiscoord < (polygonCoordsLatLong.Count); thiscoord++)
                {
                    TileSystem.LatLongToPixelXY(polygonCoordsLatLong[thiscoord].latitude, polygonCoordsLatLong[thiscoord].longitude, zoom, out int drawPix1X, out int drawPix1Y);

                    thisPointPixel.X = drawPix1X - PixelXorigin;
                    thisPointPixel.Y = drawPix1Y - PixelYorigin;
                    polygonPixels[thiscoord] = thisPointPixel;
                }

                //test each pixel in the bitmap and black out any pixel outside of the polygon
                Bitmap bmpCropped = new Bitmap(imgUncropped.Width, imgUncropped.Height);
                Bitmap gUncropped = (Bitmap)(imgUncropped);

                for (int locrow = 0; locrow < imgUncropped.Height; locrow++)
                {
                    for (int loccol = 0; loccol < imgUncropped.Width; loccol++)
                    {
                        thisPointPixel = new PointF(loccol, locrow);
                        bool inside = UtilityFunctions.IsPointInPolygon(polygonPixels, thisPointPixel);
                        if (inside)
                        {
                            bmpCropped.SetPixel(loccol, locrow, gUncropped.GetPixel(loccol, locrow));
                        } else
                        {
                            bmpCropped.SetPixel(loccol, locrow,  Color.FromArgb(0, 0, 0));
                        }

                    }
                }
                imgUncropped = bmpCropped;
            }

            //crop the image down to the desired pixel width and height. 
            //IMPORTANT: offset it to crop the 'centered' area as expected
            Rectangle cropRect = new Rectangle(minPixelX - (minTileX * tileSizeInPixels), minPixelY -(minTileY * tileSizeInPixels), 
                widthInPixels, heightInPixels);

            Bitmap target = new Bitmap(cropRect.Width, cropRect.Height);
            Bitmap src = (Bitmap)imgUncropped;

            using (Graphics g = Graphics.FromImage(target))
            {
                g.DrawImage(src, new Rectangle(0, 0, target.Width, target.Height),
                                 cropRect, GraphicsUnit.Pixel);
            }

            //Now return the reulting Cropped final bitmap as a PNG
            MemoryStream memstream = new MemoryStream();
            target.Save(memstream, System.Drawing.Imaging.ImageFormat.Png);

            memstream.Seek(0, SeekOrigin.Begin);
            Response.ContentType = "image/png";
            return memstream;
        }

        //This function takes a List of lat/longs, converts them to pixel coords, and draws them over the map
        private Image renderPolygonToBitmap(List<Coordinate> polygonCoordsLatLong,int PixelXorigin, int PixelYorigin ,int zoom,
            Image bmp, Color edgeColor, Color vertexColor)
        {
            var g = Graphics.FromImage(bmp);
            for (int thiscoord = 0; thiscoord < (polygonCoordsLatLong.Count - 1); thiscoord++)
            {
                TileSystem.LatLongToPixelXY(polygonCoordsLatLong[thiscoord].latitude, polygonCoordsLatLong[thiscoord].longitude, zoom, out int drawPix1X, out int drawPix1Y);
                TileSystem.LatLongToPixelXY(polygonCoordsLatLong[thiscoord + 1].latitude, polygonCoordsLatLong[thiscoord + 1].longitude, zoom, out int drawPix2X, out int drawPix2Y);

                g.DrawLine(new Pen(edgeColor, 2), new Point(drawPix1X - PixelXorigin, drawPix1Y - PixelYorigin), new Point(drawPix2X - PixelXorigin, drawPix2Y - PixelYorigin));

                int radius = 3;
                g.DrawEllipse(new Pen(vertexColor, 2), (drawPix1X - PixelXorigin) - radius, (drawPix1Y - PixelYorigin) - radius,
                      radius + radius, radius + radius);
            }
            return bmp;
        }

        //this function requests the needed tiles from vexcels tile services. for efficiency, each tile
        //is requested on a separate thread to gather all the tiles in parrallel 
        private Image getPropertyTiles(int originXtile, int numXtiles, int originYtile, 
            int numYtiles, int originZtile, string VexcelToken, string layerName, string AOIname)
        {
            //Create a Bitmap for the RGB tiles
            var bmp = new System.Drawing.Bitmap(tileSizeInPixels * numXtiles, tileSizeInPixels * numYtiles);
            var g = Graphics.FromImage(bmp);

            //we'll need a task per tile
            int numerOftiles = numYtiles * numXtiles;
            Task[] tasks = new Task[numerOftiles];
            
            tileImages = new TileImage[numerOftiles];
            int tileCnt = -1;
            int colIndx = 0;
            int rowIndx = 0;

            //First, loop through each desired tile and create a TileImage object to be filled asynchronously
            for (int row = originYtile; row < originYtile + numYtiles; row++)
            {
                colIndx = 0;
                for (int col = originXtile; col < originXtile + numXtiles; col++)
                {
                    tileCnt++;
                    TileImage thisTileImage = new TileImage();
                    thisTileImage.xIndx = colIndx;
                    thisTileImage.yindx = rowIndx;
                    thisTileImage.URL = "https://api.gic.org/images/GetOrthoImageTile/" + layerName + "/" + originZtile + "/" +
                           col + "/" + row + "/true?format=image%2Fjpeg&token=" + VexcelToken;
                    if (AOIname != "")
                        thisTileImage.URL += "&AOI=" + AOIname;
                    thisTileImage.requestID = "t" +tileCnt;

                    tileImages[tileCnt] = thisTileImage;
                    colIndx++;
                }
                rowIndx++;
            }

            //Now go fetch eeach tile asynchronously
            tileCnt = 0;
            DateTime startTime = DateTime.Now;
            foreach  (TileImage thisTI in tileImages)
            {
                    tasks[tileCnt] = Task.Run(() =>
                    {
                        fetchATile(thisTI);
                        int tileindx = tileCnt;
                    });
                tileCnt++;
            }

            //wait here for all threads to complete.
            Task.WaitAll(tasks);

            //loop again to stitch the tiles together into a single bitmap
            colIndx = 0;
            rowIndx = 0;
            tileCnt = -1;
            for (int row = originYtile; row < originYtile + numYtiles; row++)
            {
                colIndx = 0;
                for (int col = originXtile; col < originXtile + numXtiles; col++)
                {
                    tileCnt++;
                    g.DrawImage(tileImages[tileCnt].imgTile, tileSizeInPixels * colIndx, tileSizeInPixels * rowIndx);

                    colIndx++;
                }
                rowIndx++;
            }

            Image imageRGB = bmp;
            return imageRGB;
        }

        private TileImage fetchATile(TileImage thisTileImage)
        {
            thisTileImage.imgTile = fetchImageFromURL(thisTileImage.URL);
                        
            return thisTileImage;
        }

        private Image fetchImageFromURL(string imageURL)
        {
            Image imageRGB =null;

            if (imageURL == null || imageURL == "")
                return imageRGB;

            //fetch it
            using (WebClient webClient = new WebClient())
            {
                DateTime startTime = DateTime.Now;
                try
                {
                    byte[] data = webClient.DownloadData(imageURL);
                    MemoryStream memstream = new MemoryStream(data);
                    imageRGB = Bitmap.FromStream(memstream);

                }
                catch (Exception ex)
                {
                    imageRGB = null;
                }
            }
            return imageRGB;
        }
    }
}

        public static List<Coordinate> convertWKTPolygonToCoordinates(string wktPolygon)
        {
            wktPolygon = wktPolygon.ToUpper().Trim().Replace("))","");
            wktPolygon = wktPolygon.Replace("POLYGON((", "");
            wktPolygon = wktPolygon.Replace("  ", " ");
            wktPolygon = wktPolygon.Replace(" ", ",");
            
            List<Coordinate> parcelCoordsLatLong;             
            string[] strC = wktPolygon.Split(',');
          
            parcelCoordsLatLong = new List<Coordinate>();
            for (int indx = 0; indx < strC.Length; indx += 2)
            {
                Coordinate thisCoord = new Coordinate();
                thisCoord.longitude = double.Parse(strC[indx]);
                thisCoord.latitude = double.Parse(strC[indx + 1]);
                parcelCoordsLatLong.Add(thisCoord);
            }
            return parcelCoordsLatLong;
        }


        public static bool IsPointInPolygon(PointF[] polygon, PointF testPoint)
        {
            bool result = false;
            int j = polygon.Count() - 1;
            for (int i = 0; i < polygon.Count(); i++)
            {
                if (polygon[i].Y < testPoint.Y && polygon[j].Y >= testPoint.Y || polygon[j].Y < testPoint.Y && polygon[i].Y >= testPoint.Y)
                {
                    if (polygon[i].X + (testPoint.Y - polygon[i].Y) / (polygon[j].Y - polygon[i].Y) * (polygon[j].X - polygon[i].X) < testPoint.X)
                    {
                        result = !result;
                    }
                }
                j = i;
            }
            return result;
        }

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

namespace GICPropertyInfo
{
    static  class TileSystem
    {
        private const double EarthRadius = 6378137;
        private const double MinLatitude = -85.05112878;
        private const double MaxLatitude = 85.05112878;
        private const double MinLongitude = -180;
        private const double MaxLongitude = 180;

        /// <summary>  
        /// Clips a number to the specified minimum and maximum values.  
        /// </summary>  
        /// <param name="n">The number to clip.</param>  
        /// <param name="minValue">Minimum allowable value.</param>  
        /// <param name="maxValue">Maximum allowable value.</param>  
        /// <returns>The clipped value.</returns>  
        private static double Clip(double n, double minValue, double maxValue)
        {
            return Math.Min(Math.Max(n, minValue), maxValue);
        }

        /// <summary>  
        /// Determines the map width and height (in pixels) at a specified level  
        /// of detail.  
        /// </summary>  
        /// <param name="levelOfDetail">Level of detail, from 1 (lowest detail)  
        /// to 23 (highest detail).</param>  
        /// <returns>The map width and height in pixels.</returns>  
        public static uint MapSize(int levelOfDetail)
        {
            return (uint)256 << levelOfDetail;
        }

        /// <summary>  
        /// Determines the ground resolution (in meters per pixel) at a specified  
        /// latitude and level of detail.  
        /// </summary>  
        /// <param name="latitude">Latitude (in degrees) at which to measure the  
        /// ground resolution.</param>  
        /// <param name="levelOfDetail">Level of detail, from 1 (lowest detail)  
        /// to 23 (highest detail).</param>  
        /// <returns>The ground resolution, in meters per pixel.</returns>  
        public static double GroundResolution(double latitude, int levelOfDetail)
        {
            latitude = Clip(latitude, MinLatitude, MaxLatitude);
            return Math.Cos(latitude * Math.PI / 180) * 2 * Math.PI * EarthRadius / MapSize(levelOfDetail);
        }

        /// <summary>  
        /// Determines the map scale at a specified latitude, level of detail,  
        /// and screen resolution.  
        /// </summary>  
        /// <param name="latitude">Latitude (in degrees) at which to measure the  
        /// map scale.</param>  
        /// <param name="levelOfDetail">Level of detail, from 1 (lowest detail)  
        /// to 23 (highest detail).</param>  
        /// <param name="screenDpi">Resolution of the screen, in dots per inch.</param>  
        /// <returns>The map scale, expressed as the denominator N of the ratio 1 : N.</returns>  
        public static double MapScale(double latitude, int levelOfDetail, int screenDpi)
        {
            return GroundResolution(latitude, levelOfDetail) * screenDpi / 0.0254;
        }

        /// <summary>  
        /// Converts a point from latitude/longitude WGS-84 coordinates (in degrees)  
        /// into pixel XY coordinates at a specified level of detail.  
        /// </summary>  
        /// <param name="latitude">Latitude of the point, in degrees.</param>  
        /// <param name="longitude">Longitude of the point, in degrees.</param>  
        /// <param name="levelOfDetail">Level of detail, from 1 (lowest detail)  
        /// to 23 (highest detail).</param>  
        /// <param name="pixelX">Output parameter receiving the X coordinate in pixels.</param>  
        /// <param name="pixelY">Output parameter receiving the Y coordinate in pixels.</param>  
        public static void LatLongToPixelXY(double latitude, double longitude, int levelOfDetail, out int pixelX, out int pixelY)
        {
            latitude = Clip(latitude, MinLatitude, MaxLatitude);
            longitude = Clip(longitude, MinLongitude, MaxLongitude);

            double x = (longitude + 180) / 360;
            double sinLatitude = Math.Sin(latitude * Math.PI / 180);
            double y = 0.5 - Math.Log((1 + sinLatitude) / (1 - sinLatitude)) / (4 * Math.PI);

            uint mapSize = MapSize(levelOfDetail);
            pixelX = (int)Clip(x * mapSize + 0.5, 0, mapSize - 1);
            pixelY = (int)Clip(y * mapSize + 0.5, 0, mapSize - 1);
        }

        /// <summary>  
        /// Converts a pixel from pixel XY coordinates at a specified level of detail  
        /// into latitude/longitude WGS-84 coordinates (in degrees).  
        /// </summary>  
        /// <param name="pixelX">X coordinate of the point, in pixels.</param>  
        /// <param name="pixelY">Y coordinates of the point, in pixels.</param>  
        /// <param name="levelOfDetail">Level of detail, from 1 (lowest detail)  
        /// to 23 (highest detail).</param>  
        /// <param name="latitude">Output parameter receiving the latitude in degrees.</param>  
        /// <param name="longitude">Output parameter receiving the longitude in degrees.</param>  
        public static void PixelXYToLatLong(int pixelX, int pixelY, int levelOfDetail, out double latitude, out double longitude)
        {
            double mapSize = MapSize(levelOfDetail);
            double x = (Clip(pixelX, 0, mapSize - 1) / mapSize) - 0.5;
            double y = 0.5 - (Clip(pixelY, 0, mapSize - 1) / mapSize);

            latitude = 90 - 360 * Math.Atan(Math.Exp(-y * 2 * Math.PI)) / Math.PI;
            longitude = 360 * x;
        }

        /// <summary>  
        /// Converts pixel XY coordinates into tile XY coordinates of the tile containing  
        /// the specified pixel.  
        /// </summary>  
        /// <param name="pixelX">Pixel X coordinate.</param>  
        /// <param name="pixelY">Pixel Y coordinate.</param>  
        /// <param name="tileX">Output parameter receiving the tile X coordinate.</param>  
        /// <param name="tileY">Output parameter receiving the tile Y coordinate.</param>  
        public static void PixelXYToTileXY(int pixelX, int pixelY, out int tileX, out int tileY)
        {
            tileX = pixelX / 256;
            tileY = pixelY / 256;
        }

        /// <summary>  
        /// Converts tile XY coordinates into pixel XY coordinates of the upper-left pixel  
        /// of the specified tile.  
        /// </summary>  
        /// <param name="tileX">Tile X coordinate.</param>  
        /// <param name="tileY">Tile Y coordinate.</param>  
        /// <param name="pixelX">Output parameter receiving the pixel X coordinate.</param>  
        /// <param name="pixelY">Output parameter receiving the pixel Y coordinate.</param>  
        public static void TileXYToPixelXY(int tileX, int tileY, out int pixelX, out int pixelY)
        {
            pixelX = tileX * 256;
            pixelY = tileY * 256;
        }

        /// <summary>  
        /// Converts tile XY coordinates into a QuadKey at a specified level of detail.  
        /// </summary>  
        /// <param name="tileX">Tile X coordinate.</param>  
        /// <param name="tileY">Tile Y coordinate.</param>  
        /// <param name="levelOfDetail">Level of detail, from 1 (lowest detail)  
        /// to 23 (highest detail).</param>  
        /// <returns>A string containing the QuadKey.</returns>  
        public static string TileXYToQuadKey(int tileX, int tileY, int levelOfDetail)
        {
            StringBuilder quadKey = new StringBuilder();
            for (int i = levelOfDetail; i > 0; i--)
            {
                char digit = '0';
                int mask = 1 << (i - 1);
                if ((tileX & mask) != 0)
                {
                    digit++;
                }
                if ((tileY & mask) != 0)
                {
                    digit++;
                    digit++;
                }
                quadKey.Append(digit);
            }
            return quadKey.ToString();
        }

        public static void MetersXYToLatLong(double x, double y, out double latitude, out double longitude)
        {
            latitude = 90 - 360 * Math.Atan(Math.Exp(-y / EarthRadius)) / Math.PI;
            longitude = 360 * x / (EarthRadius * 2 * Math.PI);
        }


        /// <summary>  
        /// Converts a QuadKey into tile XY coordinates.  
        /// </summary>  
        /// <param name="quadKey">QuadKey of the tile.</param>  
        /// <param name="tileX">Output parameter receiving the tile X coordinate.</param>  
        /// <param name="tileY">Output parameter receiving the tile Y coordinate.</param>  
        /// <param name="levelOfDetail">Output parameter receiving the level of detail.</param>  
        public static void QuadKeyToTileXY(string quadKey, out int tileX, out int tileY, out int levelOfDetail)
        {
            tileX = tileY = 0;
            levelOfDetail = quadKey.Length;
            for (int i = levelOfDetail; i > 0; i--)
            {
                int mask = 1 << (i - 1);
                switch (quadKey[levelOfDetail - i])
                {
                    case '0':
                        break;

                    case '1':
                        tileX |= mask;
                        break;

                    case '2':
                        tileY |= mask;
                        break;

                    case '3':
                        tileX |= mask;
                        tileY |= mask;
                        break;

                    default:
                        throw new ArgumentException("Invalid QuadKey digit sequence.");
                }
            }
        }
    }
}