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+'use strict';
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+
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+Object.defineProperty(exports, '__esModule', { value: true });
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+
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+/**
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+ * Sunrise/sunset script. By Matt Kane. Adopted for NPM use by Alexey Udivankin.
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+ *
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+ * Based loosely and indirectly on Kevin Boone's SunTimes Java implementation
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+ * of the US Naval Observatory's algorithm.
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+ *
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+ * Copyright © 2012 Triggertrap Ltd. All rights reserved.
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+ *
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+ * This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General
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+ * Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option)
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+ * any later version.
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+ *
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+ * This library is distributed in the hope that it will be useful,but WITHOUT ANY WARRANTY; without even the implied
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+ * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
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+ * details.
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+ * You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to
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+ * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA,
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+ * or connect to: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
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+ */
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+/**
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+ * Default zenith
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+ */
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+const DEFAULT_ZENITH = 90.8333;
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+/**
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+ * Degrees per hour
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+ */
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+const DEGREES_PER_HOUR = 360 / 24;
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+/**
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+ * Msec in hour
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+ */
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+const MSEC_IN_HOUR = 60 * 60 * 1000;
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+/**
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+ * Get day of year
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+ */
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+function getDayOfYear(date) {
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+ return Math.ceil((date.getTime() - new Date(date.getFullYear(), 0, 1).getTime()) / 8.64e7);
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+}
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+/**
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+ * Get sin of value in deg
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+ */
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+function sinDeg(deg) {
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+ return Math.sin(deg * 2.0 * Math.PI / 360.0);
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+}
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+/**
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+ * Get acos of value in deg
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+ */
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+function acosDeg(x) {
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+ return Math.acos(x) * 360.0 / (2 * Math.PI);
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+}
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+/**
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+ * Get asin of value in deg
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+ */
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+function asinDeg(x) {
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+ return Math.asin(x) * 360.0 / (2 * Math.PI);
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+}
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+/**
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+ * Get tan of value in deg
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+ */
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+function tanDeg(deg) {
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+ return Math.tan(deg * 2.0 * Math.PI / 360.0);
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+}
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+/**
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+ * Get cos of value in deg
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+ */
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+function cosDeg(deg) {
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+ return Math.cos(deg * 2.0 * Math.PI / 360.0);
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+}
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+/**
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+ * Get ramainder
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+ */
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+function mod(a, b) {
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+ const result = a % b;
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+ return result < 0
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+ ? result + b
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+ : result;
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+}
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+/**
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+ * Calculate Date for either sunrise or sunset
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+ */
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+function calculate(latitude, longitude, isSunrise, zenith, date) {
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+ const dayOfYear = getDayOfYear(date);
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+ const hoursFromMeridian = longitude / DEGREES_PER_HOUR;
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+ const approxTimeOfEventInDays = isSunrise
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+ ? dayOfYear + ((6 - hoursFromMeridian) / 24)
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+ : dayOfYear + ((18.0 - hoursFromMeridian) / 24);
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+ const sunMeanAnomaly = (0.9856 * approxTimeOfEventInDays) - 3.289;
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+ const sunTrueLongitude = mod(sunMeanAnomaly + (1.916 * sinDeg(sunMeanAnomaly)) + (0.020 * sinDeg(2 * sunMeanAnomaly)) + 282.634, 360);
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+ const ascension = 0.91764 * tanDeg(sunTrueLongitude);
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+ let rightAscension;
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+ rightAscension = 360 / (2 * Math.PI) * Math.atan(ascension);
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+ rightAscension = mod(rightAscension, 360);
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+ const lQuadrant = Math.floor(sunTrueLongitude / 90) * 90;
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+ const raQuadrant = Math.floor(rightAscension / 90) * 90;
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+ rightAscension = rightAscension + (lQuadrant - raQuadrant);
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+ rightAscension /= DEGREES_PER_HOUR;
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+ const sinDec = 0.39782 * sinDeg(sunTrueLongitude);
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+ const cosDec = cosDeg(asinDeg(sinDec));
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+ const cosLocalHourAngle = ((cosDeg(zenith)) - (sinDec * (sinDeg(latitude)))) / (cosDec * (cosDeg(latitude)));
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+ const localHourAngle = isSunrise
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+ ? 360 - acosDeg(cosLocalHourAngle)
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+ : acosDeg(cosLocalHourAngle);
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+ const localHour = localHourAngle / DEGREES_PER_HOUR;
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+ const localMeanTime = localHour + rightAscension - (0.06571 * approxTimeOfEventInDays) - 6.622;
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+ const time = mod(localMeanTime - (longitude / DEGREES_PER_HOUR), 24);
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+ const utcMidnight = Date.UTC(date.getFullYear(), date.getMonth(), date.getDate());
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+ // Created date will be set to local (system) time zone.
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+ return new Date(utcMidnight + (time * MSEC_IN_HOUR));
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+}
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+/**
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+ * Calculate Sunrise time for given longitude, latitude, zenith and date
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+ */
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+function getSunrise(latitude, longitude, date = new Date()) {
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+ return calculate(latitude, longitude, true, DEFAULT_ZENITH, date);
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+}
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+/**
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+ * Calculate Sunset time for given longitude, latitude, zenith and date
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+ */
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+function getSunset(latitude, longitude, date = new Date()) {
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+ return calculate(latitude, longitude, false, DEFAULT_ZENITH, date);
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+}
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+
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+exports.getSunrise = getSunrise;
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+exports.getSunset = getSunset;
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