package org.openslx.dozmod.gui.helper;

import java.util.Calendar;
import java.util.Date;

import javax.swing.JSpinner;

import org.apache.log4j.Logger;
import org.jdatepicker.JDatePicker;

public class DateTimeHelper {

	private final static Logger LOGGER = Logger.getLogger(DateTimeHelper.class);

	/**
	 * Returns the Date composed of the given datePicker's date and the given
	 * timeSpinner's time. Returns null if the model of either one doesn't
	 * return a Date instance.
	 * 
	 * @param datePicker to extract the date from
	 * @param timeSpinner to extract the time from
	 * @return Date represented by datePicker's day and timeSpinner's time,
	 *         {@code null} on error
	 */
	public static Date getDateFrom(JDatePicker datePicker, JSpinner timeSpinner) {
		// start date from the DatePicker
		int years = datePicker.getModel().getYear();
		int months = datePicker.getModel().getMonth();
		int days = datePicker.getModel().getDay();
		Object oTime = timeSpinner.getValue();
		if (!(oTime instanceof Date) || years < 1000)
			return null;
		// start time from the Spinner
		Date time = (Date)oTime;
		Calendar calendar = Calendar.getInstance();
		calendar.setTime(time);
		int hours = calendar.get(Calendar.HOUR_OF_DAY);
		int minutes = calendar.get(Calendar.MINUTE);
		// build the time from the single values
		calendar.set(years, months, days, hours, minutes);
		Date date = calendar.getTime();
		return date;
	}

	public static Date addDaysTo(Date start, int days) {
		Calendar calendar = Calendar.getInstance();
		calendar.setTime(start);
		calendar.add(Calendar.DAY_OF_MONTH, days);
		return calendar.getTime();
	}

	/**
	 * Calculate the number of days between dates
	 * 
	 * @param start start date to use
	 * @param end end date
	 * @return Rounded number of days
	 */
	public static int calculatePeriodInDays(Date start, Date end) {
		if (end.before(start))
			return 0;
		return Math.round((end.getTime() - start.getTime()) / 86400000f);
	}

	/**
	 * Helper to set the given date's time to midnight.
	 *
	 * @param date
	 * @return date with hour, minute and seconds set to 23:59:59
	 */
	public static Date endOfDay(final Date date) {
		Calendar cal = Calendar.getInstance();
		cal.setTime(date);
		cal.set(Calendar.HOUR_OF_DAY, 23);
		cal.set(Calendar.MINUTE, 59);
		cal.set(Calendar.SECOND, 59);
		return cal.getTime();
	}
}