package org.sxkj.gd.config;


import org.apache.ibatis.type.BaseTypeHandler;
import org.apache.ibatis.type.JdbcType;
import org.apache.ibatis.type.MappedJdbcTypes;
import org.apache.ibatis.type.MappedTypes;
import org.locationtech.jts.geom.Geometry;
import org.locationtech.jts.geom.GeometryFactory;
import org.locationtech.jts.geom.PrecisionModel;
import org.locationtech.jts.io.*;

import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.sql.CallableStatement;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

@MappedTypes({String.class})
@MappedJdbcTypes({JdbcType.OTHER})
public class GeometryTypeHandler extends BaseTypeHandler<String> {


	@Override
	public void setNonNullParameter(PreparedStatement preparedStatement, int i, String s, JdbcType jdbcType) throws SQLException {


		Geometry geo = null;
		try {
			// 解析SRID(如果字符串包含SRID=4326;前缀)
			int srid = 4326; // 默认使用WGS84坐标系
			String wktString = s;
			if (s != null && s.toUpperCase().startsWith("SRID=")) {
				int semicolonIndex = s.indexOf(';');
				if (semicolonIndex > 0) {
					try {
						srid = Integer.parseInt(s.substring(5, semicolonIndex));
						wktString = s.substring(semicolonIndex + 1);
					} catch (NumberFormatException e) {
						// 如果解析失败,使用默认SRID 4326
					}
				}
			}

			// 清理WKT字符串:移除多余空格,标准化格式
			// 将 "POLYGON ((" 转换为 "POLYGON(("
			wktString = wktString.replaceAll("\\(\\s+\\(", "((").trim();

			// String转Geometry
			geo = new WKTReader(new GeometryFactory(new PrecisionModel())).read(wktString);

			// 设置Geometry的SRID
			geo.setSRID(srid);

			// Geometry转WKB
			byte[] geometryBytes = new WKBWriter(2, ByteOrderValues.LITTLE_ENDIAN, true).write(geo);
			preparedStatement.setBytes(i, geometryBytes);
		} catch (ParseException e) {
			throw new SQLException("Failed to parse geometry WKT: " + s, e);
		}
	}



	@Override
	public String getNullableResult(ResultSet resultSet, String s) {
		try (InputStream inputStream = resultSet.getBinaryStream(s)) {
			Geometry geo = getGeometryFromInputStream(inputStream);
			if (geo != null) {
				return geo.toString();
			}
		} catch (Exception e) {

		}
		return null;
	}

	@Override
	public String getNullableResult(ResultSet resultSet, int i) {
		try (InputStream inputStream = resultSet.getBinaryStream(i)) {
			Geometry geo = getGeometryFromInputStream(inputStream);
			if (geo != null) {
				return geo.toString();
			}
		} catch (Exception e) {

		}
		return null;
	}

	@Override
	public String getNullableResult(CallableStatement callableStatement, int i) throws SQLException {
		return "";
	}

	/**
	 * 流 转 geometry
	 */
	private Geometry getGeometryFromInputStream(InputStream inputStream) throws Exception {

		Geometry dbGeometry = null;

		if (inputStream != null) {
			// 二进制流转成字节数组
			byte[] buffer = new byte[255];

			int bytesRead = 0;
			ByteArrayOutputStream baos = new ByteArrayOutputStream();
			while ((bytesRead = inputStream.read(buffer)) != -1) {
				baos.write(buffer, 0, bytesRead);
			}
			// 得到字节数组
			byte[] geometryAsBytes = baos.toByteArray();
			// 字节数组小于5 异常
			if (geometryAsBytes.length < 5) {

			}

			// 字节数组前4个字节表示srid 去掉
			byte[] sridBytes = new byte[4];
			System.arraycopy(geometryAsBytes, 0, sridBytes, 0, 4);
			boolean bigEndian = (geometryAsBytes[4] == 0x00);
			// 解析srid
			int srid = 0;
			if (bigEndian) {
				for (int i = 0; i < sridBytes.length; i++) {
					srid = (srid << 8) + (sridBytes[i] & 0xff);
				}
			} else {
				for (int i = 0; i < sridBytes.length; i++) {
					srid += (sridBytes[i] & 0xff) << (8 * i);
				}
			}

			WKBReader wkbReader = new WKBReader();
			// WKBReader 把字节数组转成geometry对象。
			byte[] wkb = new byte[geometryAsBytes.length - 4];
			System.arraycopy(geometryAsBytes, 4, wkb, 0, wkb.length);
			dbGeometry = wkbReader.read(wkb);
			dbGeometry.setSRID(srid);
		}
		return dbGeometry;
	}
}