using Newtonsoft.Json;
using OSGeo.GDAL;
using OSGeo.OGR;
using SimuTools.Domain;
using System;
using System.Collections.Generic;
using System.Configuration;
using System.Diagnostics;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Threading.Tasks;

namespace SimuTools.Tools
{
    public class Handle
    {
        #region 成员变量
        public static readonly int MAX = 256 * 256;

        public static readonly double MAX_X_OFFSET = 0.002;

        public static readonly double MIN_X_OFFSET = -0.00005;

        public static readonly double WaterHeightOffset = 1.0;

        public static readonly string BaseDir = AppDomain.CurrentDomain.BaseDirectory;

        public static readonly string GdalPath = ConfigurationManager.AppSettings["gdalPath"];
        #endregion

        /// <summary>
        /// 运行
        /// </summary>
        public static void Run(Args args)
        {
            Domain.Layer layer = new Domain.Layer();
            layer.duration = new Duration();
            layer.terrain = new Terrain();
            layer.waters = new Water();

            CopeTerrain(args, layer);
            CopeBuilding(args, layer);
            CopeWater(args, layer);
            CopeFlow(args, layer);
            CopeLayerJson(args, layer);

            if (Directory.Exists(args.temp)) Directory.Delete(args.temp, true);
        }

        #region 地形
        /// <summary>
        /// 处理地形
        /// </summary>
        private static void CopeTerrain(Args args, Domain.Layer layer)
        {
            Dataset ds = null;
            try
            {
                ds = Gdal.Open(args.terrainFile, Access.GA_ReadOnly);
                if (null == ds || 0 == ds.RasterCount || null == ds.GetSpatialRef()) return;

                SetTerrainInfo(ds, layer);
                SetWaterInfo(args, layer);
                CreateTerrainPng(args, ds, layer);
            }
            finally
            {
                if (null != ds) ds.Dispose();
            }
        }

        /// <summary>
        /// 设置地形信息
        /// </summary>
        private static void SetTerrainInfo(Dataset ds, Domain.Layer layer)
        {
            //String srsName = ds.GetSpatialRef().GetName();
            //layer.terrain.epsg = !string.IsNullOrEmpty(srsName) && srsName.Contains(GdalHelper.CGCS2000) ? "EPSG:4490" : "EPSG:4326";

            Geometry minPoint = GdalHelper.GetMinPoint(ds);
            Geometry maxPoint = GdalHelper.GetMaxPoint(ds);
            double minx = GetMinVal(minPoint.GetX(0), 10000000);
            double miny = GetMinVal(minPoint.GetY(0), 10000000);
            double maxx = GetMaxVal(maxPoint.GetX(0) + MAX_X_OFFSET, 10000000);
            double maxy = GetMaxVal(maxPoint.GetY(0), 10000000);
            layer.extension = new Extension(minx, miny, maxx, maxy, double.MaxValue, double.MinValue);

            Band band = ds.GetRasterBand(1);
            double[] mm = new double[2];
            band.ComputeRasterMinMax(mm, 0);
            layer.terrain.SetHeight(GetMinVal(mm[0]), GetMaxVal(mm[1]));
        }

        /// <summary>
        /// 获取最小值
        /// </summary>
        private static double GetMinVal(double val, double radix = 1000)
        {
            return Convert.ToInt32(Math.Floor(val * radix)) / radix;
        }

        /// <summary>
        /// 获取最大值
        /// </summary>
        private static double GetMaxVal(double val, double radix = 1000)
        {
            return Convert.ToInt32(Math.Ceiling(val * radix)) / radix;
        }

        /// <summary>
        /// 创建地形PNG
        /// </summary>
        private static void CreateTerrainPng(Args args, Dataset ds, Domain.Layer layer)
        {
            string terrainPath = Path.Combine(args.outPath, "terrain");
            if (!Directory.Exists(terrainPath)) Directory.CreateDirectory(terrainPath);

            foreach (int[] sizes in layer.terrain.size)
            {
                string tif = Path.Combine(args.temp, "terrain_" + sizes[0] + "_" + sizes[1] + ".tif");
                //Resample(ds.GetDescription(), tif, sizes[0], sizes[1]);
                Resample(ds, tif, sizes[0], sizes[1], layer);
                if (!File.Exists(tif)) continue;

                string png = Path.Combine(terrainPath, sizes[0] + "_" + sizes[1] + ".png");
                Terrain2Png(layer, tif, png, sizes[0], sizes[1]);
            }
        }

        /// <summary>
        /// 重采样
        /// </summary>
        private static void Resample(Dataset ds, string dest, int width, int height, Domain.Layer layer)
        {
            // https://blog.51cto.com/u_16099346/6691820
            //string args = string.Format("-t_srs {0} -ts {1} {2} -r {3} -of {4}", "EPSG:4326", width, height, "bilinear", "GTiff");
            //string[] options = Gdal.ParseCommandLine(args);
            string[] options = new string[]
            {
                "-t_srs", "EPSG:4326", // layer.terrain.epsg,
                "-ts", width.ToString(), height.ToString(),
                "-te", layer.extension.minx.ToString(), layer.extension.miny.ToString(), layer.extension.maxx.ToString(), layer.extension.maxy.ToString(),
                "-te_srs", "EPSG:4326", // layer.terrain.epsg,
                "-r", "bilinear",
                "-of", "GTiff"
            };
            GDALWarpAppOptions warpAppOptions = new GDALWarpAppOptions(options);

            Dataset destDs = Gdal.Warp(dest, new Dataset[] { ds }, warpAppOptions, null, null);
            destDs.Dispose();
        }

        /// <summary>
        /// 地形转PNG
        /// </summary>
        private static void Terrain2Png(Domain.Layer layer, string tif, string png, int width, int height)
        {
            Dataset ds = null;
            try
            {
                ds = Gdal.Open(tif, Access.GA_ReadOnly);
                if (null == ds || 0 == ds.RasterCount) return;

                Band band = ds.GetRasterBand(1);
                float[] buffer = new float[width * height];
                band.ReadRaster(0, 0, width, height, buffer, width, height, 0, 0);

                Bitmap image = new Bitmap(width, height);
                Graphics graphic = Graphics.FromImage(image);
                graphic.Clear(Color.Transparent); // 填充透明色

                //double perHeight = (layer.terrain.maxHeight - layer.terrain.minHeight) * 100 / 65536;
                double differ = layer.extension.maxHeight - layer.extension.minHeight, minHeight = layer.extension.minHeight;
                for (int x = 0; x < width; x++)
                {
                    for (int y = 0; y < height; y++)
                    {
                        int offset = x + y * width;
                        if (float.IsNaN(buffer[offset]) || buffer[offset] < -999 || buffer[offset] < minHeight) continue;

                        //int val = Convert.ToInt32((buffer[offset] - layer.terrain.minHeight) * 100 / perHeight);
                        //int val = Convert.ToInt32((buffer[offset] - layer.terrain.minHeight) / differ * 255); // 65535
                        int r = 0, g, b;
                        if (buffer[offset] - layer.extension.maxHeight > 0)
                        {
                            g = b = 255;
                        }
                        else
                        {
                            int val = Convert.ToInt32((buffer[offset] - minHeight) / differ * 65535);
                            g = val / 256;
                            b = val % 256;
                        }

                        Color color = Color.FromArgb(127, r, g, b);
                        image.SetPixel(x, y, color);
                    }
                }
                image.Save(png, System.Drawing.Imaging.ImageFormat.Png);
            }
            finally
            {
                if (null != ds) ds.Dispose();
                //if (File.Exists(tif)) File.Delete(tif);
            }
        }
        #endregion

        #region 建筑
        /// <summary>
        /// 处理建筑
        /// </summary>
        private static void CopeBuilding(Args args, Domain.Layer layer)
        {
            Dataset ds = null;
            try
            {
                ds = Gdal.Open(args.buildingFile, Access.GA_ReadOnly);
                if (null == ds || 0 == ds.RasterCount || null == ds.GetSpatialRef()) return;

                foreach (int[] sizes in layer.terrain.size)
                {
                    string tif = Path.Combine(args.temp, "building_" + sizes[0] + "_" + sizes[1] + ".tif");
                    Resample(ds, tif, sizes[0], sizes[1], layer);
                    if (!File.Exists(tif)) continue;

                    Dataset dataset = Gdal.Open(tif, Access.GA_ReadOnly);
                    if (null == dataset || 0 == dataset.RasterCount) return;

                    float[] buffer = new float[sizes[0] * sizes[1]];
                    dataset.GetRasterBand(1).ReadRaster(0, 0, sizes[0], sizes[1], buffer, sizes[0], sizes[1], 0, 0);
                    args.buildings[sizes[0] + "_" + sizes[1]] = buffer;

                    dataset.Dispose();
                }
            }
            finally
            {
                if (null != ds) ds.Dispose();
            }
        }
        #endregion

        #region 水面
        /// <summary>
        /// 设置水面信息
        /// </summary>
        private static void SetWaterInfo(Args args, Domain.Layer layer)
        {
            List<string> files = layer.waters.files = GetFiles(args.waterPath);
            if (null == files || files.Count == 0) return;

            SetWaterData(layer, files);
            SetWaterHeight(layer, files);
        }

        /// <summary>
        /// 处理水面
        /// </summary>
        private static void CopeWater(Args args, Domain.Layer layer)
        {
            List<String> files = layer.waters.files;
            if (files.Count == 0 || files.Count != layer.waters.data.Count) return;

            ProcessWaters(args, files, layer);
        }

        /// <summary>
        /// 获取文件
        /// </summary>
        private static List<String> GetFiles(string path, string prefix = "")
        {
            string[] files = Directory.GetFiles(path, prefix + "*.tif?", SearchOption.TopDirectoryOnly);
            if (null == files || files.Length == 0) return new List<string>();

            List<string> list = files.ToList();
            list.Sort();

            return list;
        }

        /// <summary>
        /// 设置水面数据
        /// </summary>
        private static void SetWaterData(Domain.Layer layer, List<string> files)
        {
            DateTime now = DateTime.Now;
            long startTicks = new DateTime(1970, 1, 1, 8, 0, 0).Ticks;

            foreach (string file in files)
            {
                string fileName = Path.GetFileNameWithoutExtension(file);
                int hour = Convert.ToInt32(fileName.Substring(0, 2));
                int minute = Convert.ToInt32(fileName.Substring(2, 2));
                int second = Convert.ToInt32(fileName.Substring(4, 2));

                DateTime d = new DateTime(now.Year, now.Month, now.Day, hour, minute, second);
                layer.waters.data.Add((d.Ticks - startTicks) / 10000);
            }
            layer.duration.start = layer.waters.data[0];
            layer.duration.end = layer.waters.data[layer.waters.data.Count - 1];
        }

        /// <summary>
        /// 设置水面高度
        /// </summary>
        private static void SetWaterHeight(Domain.Layer layer, List<string> files)
        {
            Parallel.For(0, files.Count, i =>
            {
                Dataset ds = null;
                try
                {
                    ds = Gdal.Open(files[i], Access.GA_ReadOnly);
                    if (null == ds || 0 == ds.RasterCount || null == ds.GetSpatialRef()) return;

                    double[] mm = new double[2];
                    ds.GetRasterBand(1).ComputeRasterMinMax(mm, 0);
                    layer.extension.SetHeight(mm[0], mm[1]);
                }
                finally
                {
                    if (null != ds) ds.Dispose();
                }
            });
            layer.extension.minHeight = GetMinVal(layer.extension.minHeight - 1);
            layer.extension.maxHeight = GetMaxVal(layer.extension.maxHeight + 1);
        }

        /// <summary>
        /// 处理水面数据
        /// </summary>
        private static void ProcessWaters(Args args, List<string> files, Domain.Layer layer)
        {
            Parallel.For(0, files.Count, i =>
            //for (int i = 0; i < files.Count; i++)
            {
                Dataset ds = null;
                try
                {
                    ds = Gdal.Open(files[i], Access.GA_ReadOnly);
                    if (null == ds || 0 == ds.RasterCount || null == ds.GetSpatialRef()) return;

                    CreateWaterPng(args, ds, layer, layer.waters.data[i]);
                }
                finally
                {
                    if (null != ds) ds.Dispose();
                }
            });
        }

        /// <summary>
        /// 创建水面PNG
        /// </summary>
        private static void CreateWaterPng(Args args, Dataset ds, Domain.Layer layer, long ticks)
        {
            string waterPath = Path.Combine(args.outPath, "waters", ticks.ToString());
            if (!Directory.Exists(waterPath)) Directory.CreateDirectory(waterPath);

            foreach (int[] sizes in layer.terrain.size)
            {
                string fileName = Path.GetFileNameWithoutExtension(ds.GetDescription()) + "_" + sizes[0] + "_" + sizes[1];
                string tif = Path.Combine(args.temp, fileName + ".tif");
                Resample(ds, tif, sizes[0], sizes[1], layer);
                if (!File.Exists(tif)) continue;

                string png = Path.Combine(waterPath, sizes[0] + "_" + sizes[1] + ".png");
                Water2Png(args, layer, tif, png, sizes[0], sizes[1]);
            }
        }

        /// <summary>
        /// 水面转PNG
        /// </summary>
        private static void Water2Png(Args args, Domain.Layer layer, string tif, string png, int width, int height)
        {
            Dataset ds = null;
            try
            {
                ds = Gdal.Open(tif, Access.GA_ReadOnly);
                if (null == ds || 0 == ds.RasterCount) return;

                Band band = ds.GetRasterBand(1);
                float[] buffer = new float[width * height];
                band.ReadRaster(0, 0, width, height, buffer, width, height, 0, 0);
                float[] building = args.buildings[width + "_" + height];

                Bitmap image = new Bitmap(width, height);
                Graphics graphic = Graphics.FromImage(image);
                graphic.Clear(Color.Transparent); // 填充透明色

                //double perHeight = (layer.extension.maxHeight - layer.extension.minHeight) * 100 / 65536;
                double differ = layer.extension.maxHeight - layer.extension.minHeight, minHeight = layer.extension.minHeight;
                for (int x = 0; x < width; x++)
                {
                    for (int y = 0; y < height; y++)
                    {
                        int offset = x + y * width;
                        if (float.IsNaN(buffer[offset]) || buffer[offset] < -999 || buffer[offset] < minHeight) continue;
                        if (!float.IsNaN(building[offset]) && building[offset] > -999) continue;

                        //int val = Convert.ToInt32((buffer[offset] - layer.extension.minHeight + WaterHeightOffset) * 100 / perHeight);
                        int r = 0, g, b;
                        if (buffer[offset] - layer.extension.maxHeight > 0)
                        {
                            g = b = 255;
                        }
                        else
                        {
                            int val = Convert.ToInt32((buffer[offset] - minHeight) / differ * 65535);
                            g = val / 256;
                            b = val % 256;
                        }

                        Color color = Color.FromArgb(127, r, g, b);
                        image.SetPixel(x, y, color);
                    }
                }
                image.Save(png, System.Drawing.Imaging.ImageFormat.Png);
            }
            finally
            {
                if (null != ds) ds.Dispose();
                //if (File.Exists(tif)) File.Delete(tif);
            }
        }
        #endregion

        #region 流速流向
        /// <summary>
        /// 处理流速流向
        /// </summary>
        private static void CopeFlow(Args args, Domain.Layer layer)
        {
            List<string> vxFiles = GetFiles(args.flowPath, "vx");
            List<string> vyFiles = GetFiles(args.flowPath, "vy");
            if (null == vxFiles || null == vyFiles || vxFiles.Count != vyFiles.Count || vxFiles.Count != layer.waters.data.Count) return;

            Parallel.For(0, vxFiles.Count, i =>
            //for (int i = 0; i < vxFiles.Count; i++)
            {
                Dataset vxDs = null, vyDs = null;
                try
                {
                    vxDs = Gdal.Open(vxFiles[i], Access.GA_ReadOnly);
                    vyDs = Gdal.Open(vyFiles[i], Access.GA_ReadOnly);
                    if (null == vxDs || 0 == vxDs.RasterCount || null == vxDs.GetSpatialRef() ||
                        null == vyDs || 0 == vyDs.RasterCount || null == vyDs.GetSpatialRef()) return;

                    CreateFlowPng(args, vxDs, vyDs, layer, layer.waters.data[i]);
                }
                finally
                {
                    if (null != vxDs) vxDs.Dispose();
                    if (null != vyDs) vyDs.Dispose();
                }
            });
        }

        /// <summary>
        /// 创建流速流向PNG
        /// </summary>
        private static void CreateFlowPng(Args args, Dataset vxDs, Dataset vyDs, Domain.Layer layer, long ticks)
        {
            string flowPath = Path.Combine(args.outPath, "flows", ticks.ToString());
            if (!Directory.Exists(flowPath)) Directory.CreateDirectory(flowPath);

            foreach (int[] sizes in layer.terrain.size)
            {
                string vxName = Path.GetFileNameWithoutExtension(vxDs.GetDescription()) + "_" + sizes[0] + "_" + sizes[1];
                string vxTif = Path.Combine(args.temp, vxName + ".tif");
                Resample(vxDs, vxTif, sizes[0], sizes[1], layer);

                string vyName = Path.GetFileNameWithoutExtension(vyDs.GetDescription()) + "_" + sizes[0] + "_" + sizes[1];
                string vyTif = Path.Combine(args.temp, vyName + ".tif");
                Resample(vyDs, vyTif, sizes[0], sizes[1], layer);

                if (!File.Exists(vxTif) || !File.Exists(vyTif)) continue;

                string png = Path.Combine(flowPath, sizes[0] + "_" + sizes[1] + ".png");
                VxyTif2Png(layer, vxTif, vyTif, png, sizes[0], sizes[1]);
            }
        }

        /// <summary>
        /// 流速流向Tif值转存至Png
        /// </summary>
        private static void VxyTif2Png(Domain.Layer layer, string vxTif, string vyTif, string png, int width, int height)
        {
            Dataset vxDs = null, vyDs = null;
            try
            {
                vxDs = Gdal.Open(vxTif, Access.GA_ReadOnly);
                vyDs = Gdal.Open(vyTif, Access.GA_ReadOnly);
                if (null == vxDs || 0 == vxDs.RasterCount || null == vyDs || 0 == vyDs.RasterCount) return;

                float[] vxBuffer = new float[width * height], vyBuffer = new float[width * height];
                vxDs.GetRasterBand(1).ReadRaster(0, 0, width, height, vxBuffer, width, height, 0, 0);
                vyDs.GetRasterBand(1).ReadRaster(0, 0, width, height, vyBuffer, width, height, 0, 0);

                CreateFlowPng(vxBuffer, vyBuffer, png, width, height);
            }
            finally
            {
                if (null != vxDs) vxDs.Dispose();
                if (null != vyDs) vyDs.Dispose();
                //if (File.Exists(vxTif)) File.Delete(vxTif);
                //if (File.Exists(vyTif)) File.Delete(vyTif);
            }
        }

        /// <summary>
        /// 创建流速流向PNG
        /// </summary>
        private static void CreateFlowPng(float[] vxBuffer, float[] vyBuffer, string png, int width, int height)
        {
            Bitmap image = new Bitmap(width, height);
            Graphics graphic = Graphics.FromImage(image);
            graphic.Clear(Color.Transparent); // 填充透明色

            // 用 R通道表示，流向为归一化的二维向量（x,y），G通道表示为 x *255 , B通道表示为 y * 255
            for (int x = 0; x < width; x++)
            {
                for (int y = 0; y < height; y++)
                {
                    int offset = x + y * width;
                    float fx = GetFloatValue(vxBuffer[offset]);
                    float fy = GetFloatValue(vyBuffer[offset]);
                    if (float.IsNaN(fx) && float.IsNaN(fy) || (fx == 0 && fy == 0)) continue;

                    fx = float.IsNaN(fx) ? 0 : fx;
                    fy = float.IsNaN(fy) ? 0 : fy;
                    double dr = Math.Sqrt(Math.Pow(fx, 2) + Math.Pow(fy, 2));

                    int r = Convert.ToInt32(dr / 4 * 255);
                    int g = Convert.ToInt32((fx / dr * 0.5 + 0.5) * 255);
                    int b = Convert.ToInt32((fy / dr * 0.5 + 0.5) * 255);

                    Color color = Color.FromArgb(127, GetSafeValue(r), GetSafeValue(g), GetSafeValue(b));
                    image.SetPixel(x, y, color);
                }
            }
            image.Save(png, System.Drawing.Imaging.ImageFormat.Png);
        }

        /// <summary>
        /// 获取Float值
        /// </summary>
        private static float GetFloatValue(float val)
        {
            return (float.IsNaN(val) || val < -999) ? float.NaN : val;
        }

        /// <summary>
        /// 获取安全值
        /// </summary>
        private static int GetSafeValue(int val)
        {
            if (val < 0) return 0;
            if (val > 255) return 255;

            return val;
        }
        #endregion

        #region 元数据
        /// <summary>
        /// 处理元数据
        /// </summary>
        private static void CopeLayerJson(Args args, Domain.Layer layer)
        {
            if (null == layer) return;

            String json = JsonConvert.SerializeObject(layer);

            string filePath = Path.Combine(args.outPath, "layer.json");
            using (StreamWriter sw = new StreamWriter(filePath))
            {
                sw.Write(json);
            }
        }
        #endregion

        #region 暂时不用
        /// <summary>
        /// 设置地形信息
        /// </summary>
        private static void SetTerrainInfo(Args args, Dataset ds, Domain.Layer layer)
        {
            string tif = Path.Combine(args.temp, Path.GetFileNameWithoutExtension(ds.GetDescription()) + ".tif");
            Resample(ds, tif);
            if (!File.Exists(tif)) throw new Exception("高程文件重投影失败！");

            Dataset tifDS = null;
            try
            {
                tifDS = Gdal.Open(tif, Access.GA_ReadOnly);
                if (null == tifDS || 0 == tifDS.RasterCount || null == tifDS.GetSpatialRef()) return;

                double[] transform = new double[6];
                tifDS.GetGeoTransform(transform);
                double minx = transform[0];
                double miny = transform[3] - tifDS.RasterYSize * transform[1];
                double maxx = transform[0] + (tifDS.RasterYSize * transform[1]);
                double maxy = transform[3];

                layer.extension = new Extension(minx, miny, maxx, maxy, double.MaxValue, double.MinValue);

                Band band = tifDS.GetRasterBand(1);
                double[] mm = new double[2];
                band.ComputeRasterMinMax(mm, 0);
                layer.terrain.SetHeight(GetMinVal(mm[0]), GetMaxVal(mm[1]));
            }
            finally
            {
                if (null != tifDS) tifDS.Dispose();
            }
        }

        /// <summary>
        /// 重采样
        /// </summary>
        private static void Resample(Dataset ds, string dest)
        {
            string[] options = new string[] { "-t_srs", "EPSG:4326", "-r", "bilinear", "-of", "GTiff" };
            GDALWarpAppOptions warpAppOptions = new GDALWarpAppOptions(options);

            Dataset destDs = Gdal.Warp(dest, new Dataset[] { ds }, warpAppOptions, null, null);
            destDs.Dispose();
        }

        /// <summary>
        /// 重采样
        /// </summary>
        private static void Resample(string source, string dest, int width, int height)
        {
            // https://blog.51cto.com/u_16099346/6691820
            string cmd = string.Format("{0}gdalwarp.exe -t_srs {1} -ts {2} {3} -r {4} -of GTiff \"{5}\" \"{6}\"", GdalPath, "EPSG:4326", width, height, "bilinear", source, dest);
            string err = ExecExe(cmd);
        }

        /// <summary>
        /// 执行命令
        /// </summary>
        public static string ExecExe(string cmd)
        {
            string str = null;
            Process p = null;
            try
            {
                p = new Process();
                p.StartInfo.FileName = "cmd.exe";
                p.StartInfo.UseShellExecute = false;
                p.StartInfo.CreateNoWindow = true;
                p.StartInfo.RedirectStandardInput = true;
                p.StartInfo.RedirectStandardOutput = true;
                p.StartInfo.RedirectStandardError = true;
                p.Start();

                StreamWriter si = p.StandardInput;
                StreamReader se = p.StandardError;

                si.AutoFlush = true;
                si.WriteLine(cmd);
                si.WriteLine("exit");

                str = se.ReadToEnd();
                se.Close();
                si.Close();
            }
            catch (Exception ex)
            {
                LogOut.Error(ex.Message + "\r\n" + ex.StackTrace);
                str = ex.Message;
            }
            finally
            {
                if (p != null) p.Close();
            }
            return str;
        }
        #endregion
    }
}