package com.lf.server.service.data;

import com.lf.server.entity.all.StaticData;
import com.lf.server.helper.StringHelper;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.gdal.gdal.Dataset;
import org.gdal.gdal.gdal;
import org.gdal.gdalconst.gdalconst;
import org.gdal.ogr.Geometry;
import org.gdal.ogr.ogr;
import org.gdal.osr.SpatialReference;
import org.osgeo.proj4j.*;
import org.springframework.stereotype.Service;

import java.io.File;

/**
 * 栅格服务
 * @author WWW
 * @date 2023-08-27
 */
@Service
public class RasterService {
    private SpatialReference sr4326;

    private SpatialReference sr4490;

    private final static Log log = LogFactory.getLog(RasterService.class);

    /**
     * 初始化空间参考
     */
    public void initSr() {
        if (null == sr4326) {
            sr4326 = new SpatialReference();
            sr4326.ImportFromEPSG(StaticData.I4326);
        }
        if (null == sr4490) {
            sr4490 = new SpatialReference();
            sr4490.ImportFromEPSG(StaticData.I4490);
        }
    }

    /**
     * 获取栅格数据的EPSG编码
     */
    public Integer getRaterEpsg(String file) {
        Dataset ds = null;
        try {
            File f = new File(file);
            if (!f.exists() || f.isDirectory()) {
                return null;
            }

            ds = gdal.Open(file, gdalconst.GA_ReadOnly);
            if (null == ds || 0 == ds.getRasterCount()) {
                return null;
            }

            if (null == ds.GetSpatialRef()) {
                return null;
            }

            // PROJCS、 GEOGCS、GEOGCS 或 NULL
            String code = ds.GetSpatialRef().GetAuthorityCode(null);
            if (StringHelper.isEmpty(code)) {
                return null;
            }

            return Integer.parseInt(code);
        } catch (Exception ex) {
            log.error(ex.getMessage(), ex);
            return null;
        } finally {
            if (null != ds) {
                ds.delete();
            }
        }
    }

    /**
     * 坐标转换
     */
    public Object csTransform(double x, double y, int epsg) {
        this.initSr();

        SpatialReference srs = new SpatialReference();
        srs.ImportFromEPSG(epsg);

        Geometry point = new Geometry(ogr.wkbPoint);
        point.AddPoint(x, y, 0);
        point.AssignSpatialReference(srs);

        if (srs.GetName().contains(StaticData.CGCS2000)) {
            point.TransformTo(sr4490);
        } else {
            point.TransformTo(sr4326);
        }
        point.SwapXY();

        return new double[]{point.GetX(), point.GetY()};
    }

    /**
     * 坐标转换-使用Proj4j库
     */
    public String transformByProj4j(double x, double y, int epsg) {
        CRSFactory crsFactory = new CRSFactory();
        CoordinateReferenceSystem fromCrs = crsFactory.createFromName("EPSG:" + epsg);
        CoordinateReferenceSystem toCrs = crsFactory.createFromName("EPSG:4326");

        CoordinateTransformFactory ctf = new CoordinateTransformFactory();
        CoordinateTransform transform = ctf.createTransform(fromCrs, toCrs);

        ProjCoordinate fromCoord = new ProjCoordinate(x, y);
        ProjCoordinate toCoord = new ProjCoordinate();
        transform.transform(fromCoord, toCoord);

        return String.format("%f,%f", toCoord.x, toCoord.y);
    }
}