/*
 *   Copyright 2011 Brian Rosenberger (Brutex Network)
 *
 *   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.
 */
package net.brutex.xservices.ws.impl;

import java.math.BigInteger;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.GregorianCalendar;
import java.util.TimeZone;

import javax.jws.WebService;

import net.brutex.xservices.types.DateFormatType;
import net.brutex.xservices.types.DateTimeUnits;
import net.brutex.xservices.util.BrutexNamespaces;
import net.brutex.xservices.ws.DateService;
import net.brutex.xservices.ws.XServicesFault;


/**
 * @author Brian Rosenberger
 *
 */
@WebService(
		targetNamespace = BrutexNamespaces.WS_XSERVICES, 
		endpointInterface = "net.brutex.xservices.ws.DateService", 
		serviceName = DateService.SERVICE_NAME
			)
public class DateServiceImpl implements DateService {

	private static String ERR_INVALIDFORMAT = "Invalid format pattern.";
	private static String ERR_INVALIDTIMEZONE = "Invalid timezone.";
	
	public GregorianCalendar getDate(String timezone) throws XServicesFault {		
		if (! isValidTimezone(timezone) ) {
			String valid_ids = "";
			String[] tid = TimeZone.getAvailableIDs();
			for (String s : tid) {
				valid_ids += s + "\n";
			}
			throw new XServicesFault("Please supply a valid timezone id or none. Valid timezones are:\n" + valid_ids,
					new Exception( ));
		}
			if (timezone == null || timezone.length()<1 ) timezone = "GMT0";
			GregorianCalendar c = new GregorianCalendar(TimeZone.getTimeZone(timezone));
			return c;
	}

	
	public BigInteger getTimestamp() {
		Date d = new Date();
		long l = d.getTime();
		return new BigInteger(Long.toString(l));
	}
	
	public BigInteger getTimestamp2() {
		Date d = new Date();
		long l = d.getTime()/1000;
		return new BigInteger(Long.toString(l));
	}

	
	public GregorianCalendar getInTimezone(GregorianCalendar cal,
			String timezone) throws XServicesFault {
		if(! isValidTimezone(timezone)) throw new XServicesFault(ERR_INVALIDTIMEZONE);
		GregorianCalendar c = new GregorianCalendar(TimeZone.getTimeZone(timezone));
		c.setTimeInMillis(cal.getTimeInMillis());
		return c;
	}
	
	
	public String formatDate(GregorianCalendar cal, DateFormatType format) throws XServicesFault {
		return formatDateAdvanced(cal, format.format());
	}
	
	
	public String formatDateAdvanced(GregorianCalendar cal, String format)
			throws XServicesFault {
		String result= null;
		try {
			SimpleDateFormat f = new SimpleDateFormat(format);
			result = f.format(cal.getTime());
		} catch (IllegalArgumentException e) {
			throw new XServicesFault(ERR_INVALIDFORMAT + e.getMessage());
		}
		return result;
	}
	
	
	public GregorianCalendar parseDate(String s, DateFormatType format, String timezone) throws XServicesFault {
		return parseDateAdvanced(s, format.format(), timezone);
	}

	
	public GregorianCalendar parseDateAdvanced(String s, String format, String timezone) throws XServicesFault {
		SimpleDateFormat f = null;
		Date date = null;
		if(timezone==null | timezone.equals("")) timezone = TimeZone.getDefault().getID();
		if(! isValidTimezone(timezone)) throw new XServicesFault(ERR_INVALIDTIMEZONE);
		
		try {
			f = new SimpleDateFormat(format);
			date = f.parse(s);
		} catch(IllegalArgumentException e) {
			throw new XServicesFault(ERR_INVALIDFORMAT + e.getMessage());
		} catch (ParseException e) {
			throw new XServicesFault("Cannot parse date: "+ e.getMessage());
		}
		GregorianCalendar cal = new GregorianCalendar();
		cal.setTimeZone(TimeZone.getTimeZone(timezone));
		cal.setTime(date);
		return cal;
	}
	
	
	public BigInteger dateTimeDiff(GregorianCalendar fromCal,
			GregorianCalendar toCal) throws XServicesFault {
		long diff = toCal.getTimeInMillis() - fromCal.getTimeInMillis();
		BigInteger d = new BigInteger(String.valueOf(diff), 10);
		return d;
	}
	
	
	public BigInteger dateTimeDiff2(GregorianCalendar fromCal,
			GregorianCalendar toCal, DateTimeUnits unit) throws XServicesFault {
		BigInteger d = dateTimeDiff(fromCal, toCal);
		switch (unit) {
		case SECONDS:
			d = d.divide(new BigInteger("1000"));
			break;
		case MINUTES:
			d = d.divide(new BigInteger("60000"));
			break;
		case HOURS:
			d = d.divide(new BigInteger("3600000"));
			break;
		case DAYS:
			d = d.divide(new BigInteger("86400000"));
		}
		return d;
	}
	
	
	public GregorianCalendar dateAdd(GregorianCalendar cal, BigInteger value, DateTimeUnits unit)
			throws XServicesFault {
		switch (unit) {
		case SECONDS:
			cal.add(GregorianCalendar.SECOND, value.intValue());
			break;
		case MINUTES:
			cal.add(GregorianCalendar.MINUTE, value.intValue());
			break;
		case HOURS:
			cal.add(GregorianCalendar.HOUR_OF_DAY, value.intValue());
			break;
		case DAYS:
			cal.add(GregorianCalendar.DAY_OF_MONTH, value.intValue());
			break;
		default:
			cal.add(GregorianCalendar.MILLISECOND, value.intValue());
		}
		return cal;
	}
	
	private boolean isValidTimezone(String id) {
		boolean yes = false;
		for( String s: TimeZone.getAvailableIDs()) {
			if(s.equals(id)) {
				yes = true;
				break;
			}
		}
		return yes;
	}

}