using OSGeo.GDAL;
using OSGeo.OGR;
using OSGeo.OSR;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace SimuTools.Tools
{
    public class GdalHelper
    {
        private static bool isInited;

        private static GdalHelper instance;

        private static readonly object obj = new object();

        public static SpatialReference sr4326 { set; get; }

        public static SpatialReference sr4490 { set; get; }

        /// <summary>
        /// 构造函数
        /// </summary>
        private GdalHelper()
        {
            lock (obj)
            {
                if (!isInited)
                {
                    RegisterGDal();

                    sr4326 = new SpatialReference(null);
                    sr4326.ImportFromEPSG(4326);

                    sr4490 = new SpatialReference(null);
                    sr4490.ImportFromEPSG(4490);

                    isInited = true;
                }
            }
        }

        /// <summary>
        /// 实例
        /// </summary>
        public static GdalHelper Instance
        {
            get
            {
                lock (obj)
                {
                    if (null == instance)
                    {
                        instance = new GdalHelper();
                    }

                    return instance;
                }
            }
        }

        /// <summary>
        /// 注册GDAL
        /// </summary>
        public void RegisterGDal()
        {
            string gdalData = Path.Combine(Handle.BaseDir, "gdal-data");
            Environment.SetEnvironmentVariable("GDAL_DATA", gdalData);

            string proj7 = Path.Combine(Handle.BaseDir, "proj7\\share");
            Environment.SetEnvironmentVariable("PROJ_LIB", proj7);

            Gdal.SetConfigOption("GDAL_FILENAME_IS_UTF8", "YES"); // NO,YES
            Gdal.SetConfigOption("SHAPE_ENCODING", ""); // 空,gb2312,CP936

            Ogr.RegisterAll();
            Gdal.AllRegister();
        }
    }
}