package org.oscim.layers.vector;

import org.locationtech.jts.geom.Coordinate;
import org.locationtech.jts.geom.CoordinateSequence;
import org.locationtech.jts.geom.LineString;
import org.locationtech.jts.geom.Point;
import org.locationtech.jts.geom.Polygon;
import org.oscim.core.GeometryBuffer;

import static org.oscim.core.MercatorProjection.latitudeToY;
import static org.oscim.core.MercatorProjection.longitudeToX;

public class JtsConverter {
    double x, y, scale;
    final double outScale;

    public void setPosition(double x, double y, double scale) {
        this.x = x;
        this.y = y;
        this.scale = scale * outScale;
    }

    public JtsConverter(double outScale) {
        this.outScale = outScale;
    }

    private final Coordinate mTmpCoord = new Coordinate();

    public void transformPolygon(GeometryBuffer g, Polygon polygon) {
        Coordinate coord = mTmpCoord;

        CoordinateSequence ring = polygon.getExteriorRing().getCoordinateSequence();

        g.startPolygon();
        for (int j = 0; j < ring.size() - 1; j++) {
            ring.getCoordinate(j, coord);
            addPoint(g, coord);
        }
        for (int j = 0, n = polygon.getNumInteriorRing(); j < n; j++) {
            g.startHole();
            ring = polygon.getInteriorRingN(j).getCoordinateSequence();
            for (int k = 0; k < ring.size() - 1; k++) {
                ring.getCoordinate(k, coord);
                addPoint(g, coord);
            }
        }
    }

    public void transformLineString(GeometryBuffer g, LineString linestring) {
        Coordinate coord = mTmpCoord;

        CoordinateSequence line = linestring.getCoordinateSequence();

        g.startLine();
        for (int j = 0, n = line.size(); j < n; j++) {
            line.getCoordinate(j, coord);
            addPoint(g, coord);
        }
    }

    public void transformPoint(GeometryBuffer g, Point point) {
        Coordinate coord = mTmpCoord;

        g.startPoints();
        coord.x = point.getX();
        coord.y = point.getY();
        addPoint(g, coord);
    }

    public void addPoint(GeometryBuffer g, Coordinate coord) {
        g.addPoint((float) ((longitudeToX(coord.x) - x) * scale),
                (float) ((latitudeToY(coord.y) - y) * scale));
    }

    public void addPoint(GeometryBuffer g, double lon, double lat) {
        g.addPoint((float) ((longitudeToX(lon) - x) * scale),
                (float) ((latitudeToY(lat) - y) * scale));
    }

}