changeset-map/lib/helpers.js

import mapboxgl from 'mapbox-gl';
import turfHelpers from '@turf/helpers';
import turfBboxPolygon from '@turf/bbox-polygon';

const featureCollection = turfHelpers.featureCollection;

export function getBounds(bbox) {
    var left = +bbox.left,
        right = +bbox.right,
        top = +bbox.top,
        bottom = +bbox.bottom;

    return new mapboxgl.LngLatBounds(
    new mapboxgl.LngLat(left, bottom),
    new mapboxgl.LngLat(right, top)
  );
}

export function getBoundingBox(bounds) {
    var left = bounds.getWest(),
        right = bounds.getEast(),
        top = bounds.getNorth(),
        bottom = bounds.getSouth();

    var padX = 0;
    var padY = 0;
    if (!(left === -180 && right === 180 && top === 90 && bottom === -90)) {
        padX = Math.max((right - left) / 5, 0.0001);
        padY = Math.max((top - bottom) / 5, 0.0001);
    }

    var bboxPolygon = turfBboxPolygon([
        left - padX,
        bottom - padY,
        right + padX,
        top + padY
    ]);

    return featureCollection([bboxPolygon]);
}