package com.se.nsl.service;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.core.metadata.OrderItem;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.bc.zarr.ZarrArray;
import com.bc.zarr.ZarrGroup;
import com.se.nsl.config.PropertiesConfig;
import com.se.nsl.domain.po.Simu;
import com.se.nsl.domain.vo.SimuResult;
import com.se.nsl.domain.vo.SimuVo;
import com.se.nsl.helper.StringHelper;
import com.se.nsl.mapper.SimuMapper;
import com.se.nsl.utils.CoordinateTransformer;
import com.se.nsl.utils.TimeFormatUtil;
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.springframework.stereotype.Service;
import ucar.ma2.InvalidRangeException;

import javax.annotation.Resource;
import java.io.File;
import java.io.IOException;
import java.time.Instant;
import java.time.LocalDateTime;
import java.time.ZoneId;
import java.time.format.DateTimeFormatter;
import java.util.Arrays;
import java.util.List;

@Slf4j
@Service
@SuppressWarnings("ALL")
public class SimuService {
    public static final String TIF_EXTSION = ".tif";
    @Resource
    SimuMapper simuMapper;

    @Resource
    PropertiesConfig config;

    /**
     * 分页查询推演模拟
     *
     * @param pageNum  页码
     * @param pageSize 每页数量
     * @return 分页后的推演模拟
     */
    public IPage<Simu> selectPage(SimuVo vo, int pageNum, int pageSize) {
        QueryWrapper<Simu> wrapper = getPageWrapper(vo, pageNum, pageSize);

        Page<Simu> page = new Page<>(pageNum, pageSize);
        page.addOrder(OrderItem.desc("id"));

        IPage<Simu> paged = simuMapper.selectPage(page, wrapper);

        return paged;
    }

    private QueryWrapper<Simu> getPageWrapper(SimuVo vo, int pageNum, int pageSize) {
        QueryWrapper<Simu> wrapper = new QueryWrapper<>();
        if (null != vo.getId()) {
            wrapper.eq("id", vo.getId());
        }
        if (!StringHelper.isEmpty(vo.getName())) {
            wrapper.like("lower(name)", vo.getName().trim().toLowerCase());
        }
        if (!StringHelper.isEmpty(vo.getServiceName())) {
            wrapper.like("service_name", vo.getServiceName().trim());
        }
        if (null != vo.getType()) {
            wrapper.eq("type", vo.getType());
        }
        if (null != vo.getAreaType()) {
            wrapper.eq("area_type", vo.getAreaType());
        }
        if (null != vo.getStatus()) {
            wrapper.eq("status", vo.getStatus());
        }

        return wrapper;
    }

    /**
     * 根据ID批量删除推演模拟
     *
     * @param ids 要删除的区域ID列表
     * @return 删除成功的记录数
     */
    public int deleteByIds(List<Integer> ids) {
        return simuMapper.deleteBatchIds(ids);
    }

    /**
     * 新增推演模拟
     *
     * @param Simu 推演模拟对象
     * @return 新增成功的记录数
     */
    public int insert(Simu simu) {
        return simuMapper.insert(simu);
    }

    public int inserts(List<Simu> list) {
        return simuMapper.inserts(list);
    }

    /**
     * 根据ID查询
     *
     * @param id ID
     * @return Simu
     */
    public Simu selectById(Integer id) {
        return simuMapper.selectById(id);
    }

    /**
     * 修改推演模拟
     *
     * @param Simu 推演模拟对象
     * @return 修改成功的记录数
     */
    public int updateById(Simu simu) {
        return simuMapper.updates(Arrays.asList(simu));
    }

    public SimuResult queryByPosition(double lon, double lat, long time, String serviceName) {
        //transform coordiante from 4326 to 4548
        double[] xy = CoordinateTransformer.transform(4326, 4548, lon, lat);
//        System.out.println(String.format("转换前的坐标：x:%s,y:%s", lon, lat));
//        System.out.println(String.format("转换后的坐标：x:%s,y:%s", xy[0], xy[1]));
        //read from zarr
//        return queryByZarr(xy, time, serviceName);

        //read from tif file
        return queryByTif(xy, time, serviceName);

    }

    private SimuResult queryByZarr(double[] xy, long time, String serviceName) {
        double x = xy[0];
        double y = xy[1];
        String prefix = formatTime(time);
        File inPath = new File(config.getInPath());
//        File tifDir = new File(inPath, serviceName + File.separator + "depth");
//        int index = 0;
//        File[] files = tifDir.listFiles();
//        for (File file : files) {
//            String name = file.getName();
//            if (!name.endsWith(TIF_EXTSION)) continue;
//            if (name.equals(prefix + TIF_EXTSION)) {
//                break;
//            }
//            index++;
//        }
        File dem = new File(inPath, serviceName + File.separator + "DEM.tif");
        ColumnRow cr = getColumnRow(dem.getAbsoluteFile(), x, y);
        if (cr == null) return null;

        File zarr = new File(inPath, serviceName + File.separator + "result.zarr");
        try {
            ZarrGroup group = ZarrGroup.open(zarr.toPath());
            ZarrArray depthArray = group.openArray("depth");
            int[] shape = new int[] {60, 637, 351};
//            int[] offset = new int[]{210, 384};
            float[] depth = (float[]) depthArray.read(shape);
            System.out.println("depth:" + depth.length);
        } catch (IOException | InvalidRangeException e) {
            throw new RuntimeException(e);
        }


        return null;
    }

    private SimuResult queryByTif(double[] xy, long time, String serviceName) {
        double x = xy[0];
        double y = xy[1];
        File inPath = new File(config.getInPath());
        String prefix = formatTime(time);
        String child = serviceName + File.separator + "depth" + File.separator + prefix + TIF_EXTSION;
        File tifFile = new File(inPath, child);
        if (!tifFile.exists()) {
            return null;
        }

        ColumnRow cr = getColumnRow(tifFile, x, y);
        if (cr == null) return null;
//        System.out.println("col:" + cr.col + " ,row:" + cr.row);
        float depth = readPixelValue(cr.dataset, cr.col, cr.row, 1);
        float velocity = calcVelocity(cr.dataset, cr.col, cr.row);
        SimuResult result = new SimuResult();
        result.setDepth(depth);
        result.setVelocity(velocity);
        return  result;
    }

    private static ColumnRow getColumnRow(File tifFile, double x, double y) {
        Dataset dataset = gdal.Open(tifFile.getAbsolutePath(), gdalconstConstants.GA_ReadOnly);
        // 获取地理变换参数（6元素数组）
        // [0]: 左上角X坐标, [1]: 像元宽度, [2]: X方向旋转,
        // [3]: 左上角Y坐标, [4]: Y方向旋转, [5]: 像元高度（负值表示Y轴向下）
        double[] geoTransform = dataset.GetGeoTransform();
        //计算栅格行列号
        int col = (int) ((x - geoTransform[0]) / geoTransform[1]);
        int row = (int) ((geoTransform[3] - y) / Math.abs(geoTransform[5]));
        int width = dataset.getRasterXSize();
        int height = dataset.getRasterYSize();
        if (col < 0 || col > width || row < 0 || row > height) {
            log.warn("行列号不在tif范围内");
            return null;
        }
        return new ColumnRow(dataset, col, row);
    }

    private static class ColumnRow {
        public final Dataset dataset;
        public final int col;
        public final int row;

        public ColumnRow(Dataset dataset, int col, int row) {
            this.dataset = dataset;
            this.col = col;
            this.row = row;
        }
    }

    private float calcVelocity(Dataset dataset, int col, int row) {
        float x = readPixelValue(dataset, col, row, 2);
        float y = readPixelValue(dataset, col, row, 3);
        float velocity = 0f;
        if (Float.isNaN(x) && Float.isNaN(y)) {
            velocity = 0f;
        } else if (Float.isNaN(x)) {
            velocity = y;
        } else if (Float.isNaN(y)) {
            velocity = x;
        } else {
            velocity = (float) Math.sqrt(x * x + y * y);
        }
        return velocity;
    }

    private float readPixelValue(Dataset dataset, int col, int row, int bandNum) {
        Band band = dataset.GetRasterBand(bandNum);
        float[] values = new float[1];
        band.ReadRaster(col, row, 1, 1, values);
        return values[0];
    }

    private String formatTime(long time) {
//        Instant instant = Instant.ofEpochMilli(time);
//        LocalDateTime localDateTime = LocalDateTime.ofInstant(instant, ZoneId.systemDefault());
//        DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyyMMddHHmmss");
//        return localDateTime.format(formatter);
        return TimeFormatUtil.formatTime(time, "yyyyMMddHHmmss");
    }

}