package eu.future.earth.date;



import java.util.Calendar;

import java.util.Date;

import java.util.GregorianCalendar;



public class WeekCounter {



	@SuppressWarnings("deprecation")

	public static int getWeekOfYear(final Date date, int firstDayOfWeek, int minDaysOfFirstWeek) {

//		log("De dag is" , date);

		final GregorianCalendar tester = new GregorianCalendar();

		tester.setFirstDayOfWeek(firstDayOfWeek);

		tester.setTime(date);

		

		tester.set(Calendar.DAY_OF_WEEK, firstDayOfWeek);

		Date firstOfWeekForDate = tester.getTime();

//		log("First Day of week" , firstOfWeekForDate);

		tester.add(Calendar.DATE, 7);

		Date laatsteDagOfWeekForDate = tester.getTime();

//		log("Laatste Dag of week" , laatsteDagOfWeekForDate);

		if(laatsteDagOfWeekForDate.getYear() != firstOfWeekForDate.getYear()){

			final Date firstDayOfNextYear = getFirstDateOfYear(laatsteDagOfWeekForDate.getYear());

			int weekOneDuration = compareDate(firstOfWeekForDate, firstDayOfNextYear);

			if((7 - minDaysOfFirstWeek) >= weekOneDuration){

				return 1;

			}

		}

		if (firstOfWeekForDate.getYear() != date.getYear()) {

			return getWeekOfYearNoPrev(firstOfWeekForDate, firstDayOfWeek, minDaysOfFirstWeek);

		}

		

		final Date firstDayOfYear = getFirstDateOfYear(date.getYear());

		tester.setTime(firstDayOfYear);

		tester.set(Calendar.DAY_OF_WEEK, firstDayOfWeek);

		// tester.set(Calendar.DATE, 7);

		final Date startOfWeekForFirstDayInYear = tester.getTime();

//		log("Start of first day in week of year", startOfWeekForFirstDayInYear);



		// Check the first week

		// if its shorter that the min skip it.



		

		int count = 1;

		Date startOfWeekForFirstWeekInYear = startOfWeekForFirstDayInYear;

		if (startOfWeekForFirstDayInYear.getYear() != firstDayOfYear.getYear()) {

			tester.setTime(startOfWeekForFirstWeekInYear);

//			log("Start of First Week",  startOfWeekForFirstWeekInYear);

			int weekOneDuration = compareDate(startOfWeekForFirstWeekInYear, firstDayOfYear);

			if((minDaysOfFirstWeek) <= weekOneDuration){

				tester.add(Calendar.DATE, 7);	

				startOfWeekForFirstWeekInYear = tester.getTime();

			}

			

//			log("Start of First Week",  startOfWeekForFirstWeekInYear);

		}

//		log("Start of First Week",  startOfWeekForFirstWeekInYear);

//		if (weekOneDuration <= minDaysOfFirstWeek) {

//			count--;

//		}



		int days = compareDate(startOfWeekForFirstWeekInYear, firstOfWeekForDate);

		System.out.println(days);

		while (days >= 7) {

			days = days - 7;

			count++;

		}

		if (count == 54) {

			count = 1;

		}



		if (count == 0) {

			count = 53;

		}

		return count;

	}



	@SuppressWarnings("deprecation")

	private static Date getFirstDateOfYear(int year){

		final Date firstDayOfYear = new Date(year, Calendar.JANUARY, 1);

		return firstDayOfYear;

	}

	

	@SuppressWarnings("deprecation")

	private static int getWeekOfYearNoPrev(final Date date, int firstDayOfWeek, int minDaysOfFirstWeek) {

		final Date firstDayOfYear = getFirstDateOfYear(date.getYear());



		final GregorianCalendar tester = new GregorianCalendar();

		tester.setFirstDayOfWeek(firstDayOfWeek);

		tester.setTime(firstDayOfYear);

		tester.set(Calendar.DAY_OF_WEEK, firstDayOfWeek);



		tester.setTime(firstDayOfYear);

		tester.set(Calendar.DAY_OF_WEEK, firstDayOfWeek);

		// tester.set(Calendar.DATE, 7);

		final Date startOfWeekForFirstDayInYear = tester.getTime();

//		log("Start of first day in week of year", startOfWeekForFirstDayInYear);



		// Check the first week

		// if its shorter that the min skip it.



		

		int count = 1;

		Date startOfWeekForFirstWeekInYear = startOfWeekForFirstDayInYear;

		if (startOfWeekForFirstDayInYear.getYear() != firstDayOfYear.getYear()) {

			tester.setTime(startOfWeekForFirstWeekInYear);

//			log("Start of First Week",  startOfWeekForFirstWeekInYear);

			int weekOneDuration = compareDate(startOfWeekForFirstWeekInYear, firstDayOfYear);

			if((minDaysOfFirstWeek) <= weekOneDuration){

				tester.add(Calendar.DATE, 7);	

				startOfWeekForFirstWeekInYear = tester.getTime();

			}

			

//			log("Start of First Week",  startOfWeekForFirstWeekInYear);

		}

//		log("Start of First Week",  startOfWeekForFirstWeekInYear);

//		if (weekOneDuration <= minDaysOfFirstWeek) {

//			count--;

//		}

		tester.setTime(date);

		tester.set(Calendar.DAY_OF_WEEK, firstDayOfWeek);

		Date firstOfWeekForDate = tester.getTime();

		int days = compareDate(startOfWeekForFirstWeekInYear, firstOfWeekForDate);

		System.out.println(days);

		while (days >= 7) {

			days = days - 7;

			count++;

		}

		if (count == 54) {

			count = 1;

		}



		if (count == 0) {

			count = 53;

		}

		return count;

	}



//	private static void log(String comment, Date theDate) {

//		SimpleDateFormat formatter = new SimpleDateFormat("EEEEE dd/MM/yyyy");

//		System.out.println(comment + " " + formatter.format(theDate));

//	}



	/**

	 * Set hour, minutes, second and milliseconds to zero.

	 * 

	 * @param d

	 *            Date

	 * @return Modified date

	 */

	@SuppressWarnings("deprecation")

	public static Date setHourToZero(Date in) {

		final Date d = new Date(in.getTime());

		d.setHours(0);

		d.setMinutes(0);

		d.setSeconds(0);

		// a trick to set milliseconds to zero

		long t = d.getTime() / 1000;

		t = t * 1000;

		return new Date(t);

	}



	/**

	 * Calculate the number of days betwen two dates

	 * 

	 * @param a

	 *            Date

	 * @param b

	 *            Date

	 * @return the difference in days betwen b and a (b - a)

	 */

	public static int compareDate(Date a, Date b) {

		final Date ta = new Date(a.getTime());

		final Date tb = new Date(b.getTime());

		final long d1 = setHourToZero(ta).getTime();

		final long d2 = setHourToTen(tb).getTime();

		return (int) ((d2 - d1) / 1000 / 60 / 60 / 24);

	}



	

	

	/**

	 * Set hour to 10, minutes, second and milliseconds to zero.

	 * 

	 * @param d

	 *            Date

	 * @return Modified date

	 */

	@SuppressWarnings("deprecation")

	public static Date setHourToTen(Date in) {

		final Date d = new Date(in.getTime());

		d.setHours(10);

		d.setMinutes(0);

		d.setSeconds(0);

		// a trick to set milliseconds to zero

		long t = d.getTime() / 1000;

		t = t * 1000;

		return new Date(t);

	}



}