package ru.olamedia.astronomy;

// package com.bradsbrain.simpleastronomy;
/*
 *  Copyright 2011 Brad Parks
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import java.text.DateFormat;
import static java.text.DateFormat.SHORT;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.TimeZone;

public final class BaseUtils {

	public static double exactDaysSince(Calendar myCal, double epoch) {
		return JulianDate.makeJulianDateUsingMyModified(myCal) - epoch;
	}

	public static Calendar getSafeLocalCopy(long millis) {
		// safe local copy
		Calendar myCal = Calendar.getInstance(TimeZone.getTimeZone("GMT"));
		myCal.clear();
		myCal.setTimeInMillis(millis);
		return myCal;
	}

	public static double adjustTo360Range(double valToAdjust) {
		double howMany = Math.floor(valToAdjust / 360);
		double adjustedValue = valToAdjust - (howMany * 360);
		return adjustedValue;
	}

	public static double sinDegrees(double angleInDegrees) {
		return Math.sin(Math.toRadians(angleInDegrees));
	}

	public static double cosDegrees(double angleInDegrees) {
		return Math.cos(Math.toRadians(angleInDegrees));
	}

	public static double useLessPrecision(double d, int precision) {
		double digits = Math.pow(10, precision);
		return Math.round(d * digits) / digits;
	}

	/**
	 * Useful date-to-string formatting which I found myself using a lot
	 * 
	 * @param moonDate
	 * @return the date in GMT timezone
	 */
	public static String formatDateForGMT(Date moonDate) {
		DateFormat sdf = SimpleDateFormat.getDateInstance(SHORT);
		((SimpleDateFormat) sdf).applyPattern("yyyy-MM-dd");
		((SimpleDateFormat) sdf).setTimeZone(TimeZone.getTimeZone("GMT"));
		return sdf.format(moonDate);
	}

	/**
	 * Useful date-to-string formatting which I found myself using a lot
	 * 
	 * @param moonDate
	 * @param tz
	 *            the timezone with which to format the date
	 * @return the date in whatever timezone is default
	 */
	public static String formatDateAsShortDateLocalTime(Date moonDate,
			TimeZone tz) {
		DateFormat sdf = SimpleDateFormat.getDateInstance(SHORT);
		sdf.setTimeZone(tz);
		((SimpleDateFormat) sdf).applyPattern("yyyy-MM-dd");
		return sdf.format(moonDate);
	}

}