package com.lf.server.helper;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.gdal.ogr.*;

import java.lang.reflect.Field;
import java.sql.Timestamp;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.LocalTime;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * GDB帮助类
 * @author WWW
 */
public class GdbHelper {
    private final static Log log = LogFactory.getLog(GdbHelper.class);

    public static List<String> excludeFields = new ArrayList<String>();

    static {
        excludeFields.add("gid");
        excludeFields.add("shape_leng");
    }

    /**
     * 获取表名
     */
    public static List<String> getTabNames(String filePath) {
        List<String> list = new ArrayList<>();
        try {
            org.gdal.ogr.Driver driver = ogr.GetDriverByName("OpenFileGDB");
            if (null == driver) {
                return list;
            }

            DataSource dataSource = driver.Open(filePath, 0);
            if (null == dataSource) {
                return list;
            }

            for (int i = 0, count = dataSource.GetLayerCount(); i < count; i++) {
                Layer layer = dataSource.GetLayer(i);
                list.add(layer.GetName());

                layer.delete();
            }

            dataSource.delete();
            driver.delete();
        } catch (Exception ex) {
            log.error(ex.getMessage(), ex);
        }

        return list;
    }

    /**
     * 读取数据
     */
    public static <T> List<T> readData(Class clazz, String filePath, String layerName) {
        List<T> list = new ArrayList<>();
        try {
            org.gdal.ogr.Driver driver = ogr.GetDriverByName("OpenFileGDB");
            if (null == driver) {
                return list;
            }

            DataSource dataSource = driver.Open(filePath, 0);
            if (null == dataSource) {
                return list;
            }

            for (int i = 0, count = dataSource.GetLayerCount(); i < count; i++) {
                Layer layer = dataSource.GetLayer(i);

                if (layer.GetName().equals(layerName)) {
                    GdbHelper.readLayer(clazz, layer, list);
                    break;
                }

                layer.delete();
            }

            dataSource.delete();
            driver.delete();
        } catch (Exception ex) {
            log.error(ex.getMessage(), ex);
        }

        return list;
    }

    /**
     * 读取图层
     */
    public static <T> void readLayer(Class clazz, Layer layer, List<T> list) {
        try {
            Field gField = getGeomField(clazz);
            Map<Integer, Field> map = getFieldMapper(clazz, layer);
            if (map.size() == 0) {
                return;
            }
            if (1 > layer.GetFeatureCount()) {
                return;
            }

            do {
                Feature f = layer.GetNextFeature();
                if (null == f) {
                    break;
                }

                T t = (T) clazz.newInstance();
                if (readFeature(t, f, map, gField)) {
                    list.add(t);
                }
            } while (true);
        } catch (Exception ex) {
            log.error(ex.getMessage(), ex);
        } finally {
            if (null != layer) {
                layer.delete();
            }
        }
    }

    /**
     * 获取 geom 字段
     */
    private static Field getGeomField(Class clazz) {
        try {
            Field gField = clazz.getDeclaredField("geom");
            gField.setAccessible(true);

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

    /**
     * 获取字段映射
     */
    private static <T> Map<Integer, Field> getFieldMapper(Class clazz, Layer layer) {
        Map<Integer, Field> map = new HashMap<>(3);

        try {
            FeatureDefn fd = layer.GetLayerDefn();
            for (int i = 0, count = fd.GetFieldCount(); i < count; i++) {
                FieldDefn fieldDefn = fd.GetFieldDefn(i);
                try {
                    String name = fieldDefn.GetName().toLowerCase();
                    if (excludeFields.contains(name)){
                        continue;
                    }

                    Field field = clazz.getDeclaredField(name);
                    field.setAccessible(true);

                    map.put(i, field);
                } catch (Exception e) {
                    //
                }
            }
        } catch (Exception ex) {
            //
        }

        return map;
    }

    /**
     * 读取Feature
     */
    private static <T> boolean readFeature(T t, Feature f, Map<Integer, Field> map, Field gField) {
        try {
            for (Integer i : map.keySet()) {
                Field field = map.get(i);
                setValue(t, f, field, i);
            }

            if (null != gField) {
                setGeom(t, f, gField);
            }

            return true;
        } catch (Exception ex) {
            return false;
        }
    }

    /**
     * 设置值
     */
    private static <T> void setValue(T t, Feature f, Field field, Integer i) throws Exception {
        switch (field.getType().toString()) {
            case "class java.math.BigDecimal":
            case "class java.lang.Double":
            case "double":
                field.set(t, f.GetFieldAsDouble(i));
                break;
            case "class java.lang.Long":
            case "long":
                field.set(t, f.GetFieldAsInteger64(i));
                break;
            case "class java.lang.Integer":
            case "int":
                field.set(t, f.GetFieldAsInteger(i));
                break;
            case "class java.sql.Timestamp":
                field.set(t, getTimestamp(f, i));
                break;
            default:
                field.set(t, f.GetFieldAsString(i));
                break;
        }
    }

    /**
     * 设置 geom 字段值
     * <p>
     * wkbUnknown = 0,
     * wkbPoint = 1,
     * wkbLineString = 2,
     * wkbPolygon = 3,
     * wkbMultiPoint = 4,
     * wkbMultiLineString = 5,
     * wkbMultiPolygon = 6,
     * wkbGeometryCollection = 7,
     * wkbNone = 100,
     * wkbLinearRing = 101
     */
    private static <T> void setGeom(T t, Feature f, Field gField) throws Exception {
        Geometry geometry = f.GetGeometryRef();
        if (null != geometry) {
            String wkt = geometry.ExportToWkt();
            switch (geometry.GetGeometryType()) {
                case 2:
                    wkt = wkt.replace("LINESTRING (", "MULTILINESTRING ((") + ")";
                    break;
                case 3:
                    wkt = wkt.replace("POLYGON (", "MULTIPOLYGON ((") + ")";
                    break;
                default:
                    break;
            }

            gField.set(t, String.format("ST_GeomFromText('%s')", wkt));
        }
    }

    /**
     * 获取 Timestamp
     */
    private static Timestamp getTimestamp(Feature f, int index) {
        int[] pnYear = new int[1];
        int[] pnMonth = new int[1];
        int[] pnDay = new int[1];
        int[] pnHour = new int[1];
        int[] pnMinute = new int[1];
        float[] pfSecond = new float[1];
        int[] pnTzFlag = new int[1];

        f.GetFieldAsDateTime(index, pnYear, pnMonth, pnDay, pnHour, pnMinute, pfSecond, pnTzFlag);

        float fSecond = pfSecond[0];
        int s = (int) fSecond;
        int ns = (int) (1000000000 * fSecond - s);

        LocalDateTime localDateTime = LocalDateTime.of(
                LocalDate.of(pnYear[0], pnMonth[0], pnDay[0]),
                LocalTime.of(pnHour[0], pnMinute[0], s, ns)
        );

        Timestamp timestamp = Timestamp.valueOf(localDateTime);

        return timestamp;
    }
}