/***********************************************************************************
 * Copyright (c) 2018 /// Project SWG /// www.projectswg.com                       *
 *                                                                                 *
 * ProjectSWG is the first NGE emulator for Star Wars Galaxies founded on          *
 * July 7th, 2011 after SOE announced the official shutdown of Star Wars Galaxies. *
 * Our goal is to create an emulator which will provide a server for players to    *
 * continue playing a game similar to the one they used to play. We are basing     *
 * it on the final publish of the game prior to end-game events.                   *
 *                                                                                 *
 * This file is part of Holocore.                                                  *
 *                                                                                 *
 * --------------------------------------------------------------------------------*
 *                                                                                 *
 * Holocore is free software: you can redistribute it and/or modify                *
 * it under the terms of the GNU Affero General Public License as                  *
 * published by the Free Software Foundation, either version 3 of the              *
 * License, or (at your option) any later version.                                 *
 *                                                                                 *
 * Holocore is distributed in the hope that it will be useful,                     *
 * but WITHOUT ANY WARRANTY; without even the implied warranty of                  *
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the                   *
 * GNU Affero General Public License for more details.                             *
 *                                                                                 *
 * You should have received a copy of the GNU Affero General Public License        *
 * along with Holocore.  If not, see <http://www.gnu.org/licenses/>.               *
 ***********************************************************************************/
package com.projectswg.holocore.utilities;

public class MathUtils {
	
	// http://en.wikipedia.org/wiki/Julian_day#Converting_Julian_or_Gregorian_calendar_date_to_Julian_Day_Number
	public static int julianDay(int year, int month, int day) {
		int a = (14 - month) / 12;
		int y = year + 4800 - a;
		int m = month + 12 * a - 3;
		return day + Math.floorDiv(153 * m + 2, 5) + (365 * y) + Math.floorDiv(y, 4) - Math.floorDiv(y, 100) + Math.floorDiv(y, 400) - 32045;
	}
	
	// Used for calculating born dates
	public static int numberDaysSince(int y1, int m1, int d1, int y2, int m2, int d2) {
		return julianDay(y1, m1, d1) - julianDay(y2, m2, d2);
	}
	
}
