package org.gcube.portlets.user.speciesdiscovery.server.util;

import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.TimeZone;

import org.apache.log4j.Logger;
import org.gcube.portlets.user.speciesdiscovery.client.ConstantsSpeciesDiscovery;
import org.joda.time.DateTime;
import org.joda.time.Days;



/**
 * The Class DateUtil.
 *
 * @author Francesco Mangiacrapa francesco.mangiacrapa@isti.cnr.it
 * Feb 10, 2017
 */
public class DateUtil {

	/**
	 * The Enum TIMETYPE.
	 *
	 * @author Francesco Mangiacrapa francesco.mangiacrapa@isti.cnr.it
	 * Feb 10, 2017
	 */
	public static enum TIMETYPE{DAYS, HOURS, MINUTES, SECONDS};

	public static Logger logger = Logger.getLogger(DateUtil.class);

	public static final String DATE_TIME_FORMAT = "yyyy.MM.dd 'at' HH:mm:ss";


	public static final String DATE_TIME_FORMAT_2 = "dd-MM, yyyy HH:mm:ss z";


	/**
	 * To date.
	 *
	 * @param calendar the calendar
	 * @return the date
	 */
	public static Date toDate(Calendar calendar)
	{
		if (calendar == null) return new Date(0);
		return calendar.getTime();

	}

	/**
	 * To date format to string.
	 *
	 * @param calendar the calendar
	 * @return the string
	 */
	public static String toDateFormatToString(Calendar calendar){

		SimpleDateFormat dateFormat = new SimpleDateFormat(DATE_TIME_FORMAT);

		Date resultdate = getDate(calendar);

		return dateFormat.format(resultdate);
	}


	/**
	 * To date format.
	 *
	 * @param calendar the calendar
	 * @return the date
	 */
	public static Date toDateFormat(Calendar calendar){

		SimpleDateFormat dateFormat = new SimpleDateFormat(DATE_TIME_FORMAT);

		Date resultdate = getDate(calendar);

		try {

			resultdate = dateFormat.parse(dateFormat.format(resultdate));

		} catch (ParseException e) {
			logger.error(e.getMessage());
			resultdate = new Date(0);
		}

		return resultdate;
	}


	/**
	 * Gets the date format.
	 *
	 * @param calendar the calendar
	 * @return the date format
	 */
	public static Date getDateFormat(Calendar calendar){

		SimpleDateFormat dateFormat = new SimpleDateFormat(DATE_TIME_FORMAT);
		Date resultdate = null;

		if (calendar == null)
			resultdate = new Date(0);
		else
			resultdate = getDate(calendar);

		try {

			resultdate = dateFormat.parse(dateFormat.format(resultdate));

		} catch (ParseException e) {
			logger.error(e.getMessage());
			resultdate = new Date(0);
		}

		return resultdate;
	}


	/**
	 * Gets the date.
	 *
	 * @param calendar the calendar
	 * @return the date
	 */
	public static Date getDate(Calendar calendar) {

		Date resultdate = null;

		if (calendar == null)
			resultdate = new Date(0);
		else
			resultdate = new Date(calendar.getTimeInMillis());

		return resultdate;

	}

	/**
	 * String to date format.
	 *
	 * @param date the date
	 * @return the date
	 */
	public static Date stringToDateFormat(String date){

		SimpleDateFormat dateFormat = new SimpleDateFormat(DATE_TIME_FORMAT);
		Date resultdate = null;

		try {
			resultdate =  dateFormat.parse(date);
		} catch (ParseException e) {
			logger.error(e.getMessage());
			resultdate = new Date(0);
		}

		return resultdate;
	}


	/**
	 * Date to date format string.
	 *
	 * @param date the date
	 * @return the string
	 */
	public static String dateToDateFormatString(Date date){

		SimpleDateFormat dateFormat = new SimpleDateFormat(DATE_TIME_FORMAT);
		String dateString = null;

		if(date!=null)
			dateString =  dateFormat.format(date);
		else
			dateString = dateFormat.format(new Date(0));

		return dateString;
	}

	/**
	 * Milliseconds to date.
	 *
	 * @param milliseconds the milliseconds
	 * @return the date
	 */
	public static Date millisecondsToDate(long milliseconds){

		Date date = null;

		try {
			 date= new Date(milliseconds);
		} catch (Exception e) {
			logger.error(e.getMessage());
			date = new Date(0);
		}

		return date;
	}

	/**
	 * Gets the difference.
	 *
	 * @param date1 the date1
	 * @param date2 the date2
	 * @param timeType the time type
	 * @return the difference
	 */
	public static long getDifference(long date1, long date2, TIMETYPE timeType){

		// Calculates the difference in milliseconds.
		  long millisDiff = date2 - date1;

		  switch (timeType) {
		  	case DAYS: return millisDiff / 86400000;
		  	case HOURS: return millisDiff / 3600000 % 24;
		  	case MINUTES: return millisDiff / 60000 % 60;
		  	case SECONDS: return millisDiff / 1000 % 60;

		  	default:
		  		return millisDiff / 1000 % 60;
		}
	}


	/**
	 * Gets the difference.
	 *
	 * @param date1 the date1
	 * @param date2 the date2
	 * @return difference between two date in this format: N°day/days HH:mm:ss
	 */
	public static String getDifference(long date1, long date2){
		long millisDiff = date2 - date1;
//		System.out.println("millisDiff: "+millisDiff);
		Date date = new Date(millisDiff);
		DateFormat outFormat = new SimpleDateFormat(ConstantsSpeciesDiscovery.TIMEFORMAT_HH_MM_SS);
		outFormat.setTimeZone(TimeZone.getTimeZone(ConstantsSpeciesDiscovery.TIME_ZONE_UTC));
		int days = Days.daysBetween(new DateTime(date1), new DateTime(date2)).getDays();

		if(days>0){
			String hours = outFormat.format(date);
			return days==1?days + " Day, "+hours:days + " Days, "+hours;
		}
		else
			return outFormat.format(date);

	}

}