package com.se.simu.service;

import com.se.simu.config.PropertiesConfig;
import com.se.simu.domain.vo.*;
import lombok.extern.slf4j.Slf4j;
import org.gdal.gdal.Band;
import org.gdal.gdal.Dataset;
import org.gdal.gdal.gdal;
import org.gdal.gdalconst.gdalconstConstants;
import org.gdal.osr.SpatialReference;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;
import java.io.File;
import java.io.FileInputStream;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

/**
 * 内涝服务类
 *
 * @author WWW
 * @date   2024-07-16
 */
@Slf4j
@Service
public class WaterService {
    @Resource
    PropertiesConfig config;

    /**
     * 获取元数据信息
     */
    public byte[] getLayerJson(String serviceName) {
        try {
            String filePath = config.getOutPath() + File.separator + serviceName + File.separator + "layer.json";

            File dat = new File(filePath);
            if (!dat.exists()) {
                return null;
            }

            byte[] bytes = new byte[(int) dat.length()];

            FileInputStream fs = new FileInputStream(filePath);
            fs.read(bytes);
            fs.close();

            return bytes;
        } catch (Exception ex) {
            return null;
        }
    }

    /**
     * 获取地形高度图
     */
    public String getTerraMap(String serviceName, Integer width, Integer height) {
        return config.getOutPath() + File.separator + serviceName + File.separator + "terrain" + File.separator + width + "_" + height + ".png";
    }

    /**
     * 获取水面高度图
     */
    public String getWaterMap(String serviceName, Integer width, Integer height, Long timestamp) {
        return config.getOutPath() + File.separator + serviceName + File.separator + "waters" + File.separator + timestamp + File.separator + width + "_" + height + ".png";
    }

    /**
     * 获取水流向流速图
     */
    public String getFlowMap(String serviceName, Integer width, Integer height, Long timestamp) {
        return config.getOutPath() + File.separator + serviceName + File.separator + "flows" + File.separator + timestamp + File.separator + width + "_" + height + ".png";
    }

    /**
     * 获取图层 *
     */
    public Layer getLayer(String serviceName) {
        Layer layer = new Layer();
        layer.setVersion(config.getVer());
        layer.setDuration(new Duration(1719812810225L, 1719812810225L));
        layer.setExtension(new Extension(2.11062743358, 0.53812160220, 2.11070827834, 0.53819799453, 1.151, 38.83));

        List<Integer[]> sizes = new ArrayList<>();
        sizes.add(new Integer[]{64, 64});
        sizes.add(new Integer[]{128, 128});
        sizes.add(new Integer[]{256, 256});
        sizes.add(new Integer[]{512, 512});
        sizes.add(new Integer[]{1024, 1024});
        sizes.add(new Integer[]{2048, 2048});
        layer.setTerrain(new Terrain(sizes));

        List<Long> data = new ArrayList<>(Arrays.asList(1719812812225L, 1719812812225L, 1719812812225L, 1719812812225L, 1719812812225L, 1719812812225L));
        layer.setWaters(new Water(data));

        return layer;
    }

    /**
     * 获取降水曲线文件曲线图
     */
    public byte[] getRainfall(String serviceName) {
        try {
            String filePath = config.getOutPath() + File.separator + serviceName + File.separator + "rainfall.json";

            File rainfall = new File(filePath);
            if (!rainfall.exists()) {
                return null;
            }

            byte[] bytes = new byte[(int) rainfall.length()];

            FileInputStream fs = new FileInputStream(filePath);
            fs.read(bytes);
            fs.close();

            return bytes;
        } catch (Exception ex) {
            return null;
        }
    }

    /**
     * 根据坐标查询积水深度
     */
    public Double getWaterHeight(String serviceName, Double x, Double y, Long timestamp) {
        String filePath = config.getOutPath() + File.separator + serviceName + File.separator + "waters"
                + File.separator + timestamp + File.separator + "water.tif";

        // 首先是所有gdal程序都需要的注册语句
        gdal.AllRegister();
        // 读取影像
        Dataset hDataset = gdal.Open(filePath, gdalconstConstants.GA_Update);

        // 设置数据集的投影
        SpatialReference srs = new SpatialReference();
        srs.ImportFromEPSG(4548);
        hDataset.SetProjection(srs.ExportToWkt());

        //获取栅格数量
        int numBands=hDataset.GetRasterCount();
        System.out.println("RasterCount: " + numBands);
        //构造仿射变换参数数组，并获取数据
        double[] gt = new double[6];
        hDataset.GetGeoTransform(gt);
        System.out.println("仿射变换参数"+ Arrays.toString(gt));

        //经纬度转换为栅格像素坐标
        int[] ColRow=Coordinates2ColRow(gt,x,y);

        //判断是否坐标超出范围
        if(ColRow[0]<0||ColRow[1]<0||ColRow[0]>hDataset.getRasterXSize()||ColRow[1]>hDataset.getRasterYSize()){
            System.out.println(Arrays.toString(ColRow)+"坐标值超出栅格范围！");
            return null;
        }

        //获取该点对应的波段的值
        Band band = hDataset.GetRasterBand(1);
        double[] values = new double[1];
        band.ReadRaster(ColRow[0], ColRow[1], 1, 1, values);
        double value = values[0];

        //释放资源
        hDataset.delete();
        return value;
    }

    /**
     * 将地图坐标转换为栅格像素坐标
     * @param gt 仿射变换参数
     * @param X 横坐标
     * @param Y 纵坐标
     * @return
     */
    public int[] Coordinates2ColRow(double[] gt, double X, double Y){
        int[] ints = new int[2];
        //向下取整,如果向上取整会导致计算结果偏大，从而在后面读取到邻近像元的数据
        double  Yline = Math.floor(((Y - gt[3])*gt[1] - (X-gt[0])*gt[4]) / (gt[5]*gt[1]-gt[2]*gt[4]));
        double  Xpixel = Math.floor((X-gt[0] - Yline*gt[2])/gt[1]);
        ints[0] = new Double(Xpixel).intValue();
        ints[1] = new Double(Yline).intValue();
        return ints;
    }
}