EDIT

/**

* Copyright (C) 2007 EDIT

* European Distributed Institute of Taxonomy 

* http://www.e-taxonomy.eu

* 

* The contents of this file are subject to the Mozilla Public License Version 1.1

* See LICENSE.TXT at the top of this package for the full license terms.

*/

package eu.etaxonomy.cdm.model.common;

import java.io.Serializable;

import java.text.DateFormat;

import java.text.ParsePosition;

import java.util.Calendar;

import java.util.Date;

import java.util.regex.Matcher;

import java.util.regex.Pattern;

import javax.persistence.Embeddable;

import javax.persistence.Transient;

import javax.xml.bind.annotation.XmlAccessType;

import javax.xml.bind.annotation.XmlAccessorType;

import javax.xml.bind.annotation.XmlElement;

import javax.xml.bind.annotation.XmlRootElement;

import javax.xml.bind.annotation.XmlType;

import javax.xml.bind.annotation.adapters.XmlJavaTypeAdapter;

import org.apache.commons.lang.time.DateUtils;

import org.apache.log4j.Logger;

import org.hibernate.annotations.Type;

import org.hibernate.search.annotations.Field;

import org.hibernate.search.annotations.FieldBridge;

import org.joda.time.DateTime;

import org.joda.time.DateTimeFieldType;

import org.joda.time.LocalDate;

import org.joda.time.Partial;

import org.joda.time.ReadableInstant;

import org.joda.time.ReadablePartial;

import org.joda.time.format.DateTimeFormatter;

import eu.etaxonomy.cdm.common.CdmUtils;

import eu.etaxonomy.cdm.hibernate.PartialBridge;

import eu.etaxonomy.cdm.jaxb.PartialAdapter;

/**

 * @author m.doering

 * @version 1.0

 * @created 08-Nov-2007 13:07:00

 * @updated 05-Dec-2008 23:00:05

 */

@XmlAccessorType(XmlAccessType.FIELD)

@XmlType(name = "TimePeriod", propOrder = {

    "start",

    "end",

    "freeText"

})

@XmlRootElement(name = "TimePeriod")

@Embeddable

public class TimePeriod implements Cloneable, Serializable {

	private static final Logger logger = Logger.getLogger(TimePeriod.class);

	public static final DateTimeFieldType MONTH_TYPE = DateTimeFieldType.monthOfYear();

	public static final DateTimeFieldType YEAR_TYPE = DateTimeFieldType.year();

	public static final DateTimeFieldType DAY_TYPE = DateTimeFieldType.dayOfMonth();

	@XmlElement(name = "Start")

	@XmlJavaTypeAdapter(value = PartialAdapter.class)

	@Type(type="partialUserType")

	@Field(index = org.hibernate.search.annotations.Index.UN_TOKENIZED)

	@FieldBridge(impl = PartialBridge.class)

	private Partial start;

	@XmlElement(name = "End")

	@XmlJavaTypeAdapter(value = PartialAdapter.class)

	@Type(type="partialUserType")

	@Field(index = org.hibernate.search.annotations.Index.UN_TOKENIZED)

	@FieldBridge(impl = PartialBridge.class)

	private Partial end;

	@XmlElement(name = "FreeText")

	private String freeText;

	/**

	 * Factory method

	 * @return

	 */

	public static TimePeriod NewInstance(){

		return new TimePeriod();

	}

	/**

	 * Factory method

	 * @return

	 */

	public static TimePeriod NewInstance(Partial startDate){

		return new TimePeriod(startDate);

	}

	/**

	 * Factory method

	 * @return

	 */

	public static TimePeriod NewInstance(Partial startDate, Partial endDate){

		return new TimePeriod(startDate, endDate);

	}

	/**

	 * Factory method

	 * @return

	 */

	public static TimePeriod NewInstance(Integer year){

		Integer endYear = null;

		return NewInstance(year, endYear);

	}

	/**

	 * Factory method

	 * @return

	 */

	public static TimePeriod NewInstance(Integer startYear, Integer endYear){

		Partial startDate = null;

		Partial endDate = null;

		if (startYear != null){

			startDate = new Partial().with(YEAR_TYPE, startYear);

		}

		if (endYear != null){

			endDate = new Partial().with(YEAR_TYPE, endYear);

		}

		return new TimePeriod(startDate, endDate);

	}

	/**

	 * Factory method to create a TimePeriod from a <code>Calendar</code>. The Calendar is stored as the starting instant.   

	 * @return

	 */

	public static TimePeriod NewInstance(Calendar startCalendar){

		return NewInstance(startCalendar, null);

	}

	/**

	 * Factory method to create a TimePeriod from a <code>ReadableInstant</code>(e.g. <code>DateTime</code>).

	 * The <code>ReadableInstant</code> is stored as the starting instant.   

	 * @return

	 */

	public static TimePeriod NewInstance(ReadableInstant readableInstant){

		return NewInstance(readableInstant, null);

	}

	/**

	 * Factory method to create a TimePeriod from a starting and an ending <code>Calendar</code>   

	 * @return

	 */

	public static TimePeriod NewInstance(Calendar startCalendar, Calendar endCalendar){

		Partial startDate = null;

		Partial endDate = null;

		if (startCalendar != null){

			startDate = calendarToPartial(startCalendar);

		}

		if (endCalendar != null){

			endDate = calendarToPartial(endCalendar);

		}

		return new TimePeriod(startDate, endDate);

	}

	/**

	 * Factory method to create a TimePeriod from a starting and an ending <code>ReadableInstant</code>(e.g. <code>DateTime</code>)   

	 * @return

	 */

	public static TimePeriod NewInstance(ReadableInstant startInstant, ReadableInstant endInstant){

		Partial startDate = null;

		Partial endDate = null;

		if (startInstant != null){

			startDate = readableInstantToPartial(startInstant);

		}

		if (endInstant != null){

			endDate = readableInstantToPartial(endInstant);

		}

		return new TimePeriod(startDate, endDate);

	}

	/**

	 * Transforms a <code>Calendar</code> into a <code>Partial</code>

	 * @param calendar

	 * @return

	 */

	public static Partial calendarToPartial(Calendar calendar){

		LocalDate ld = new LocalDate(calendar);

		Partial partial = new Partial(ld);

		return partial;

	}

	/**

	 * Transforms a <code>Calendar</code> into a <code>Partial</code>

	 * @param calendar

	 * @return

	 */

	public static Partial readableInstantToPartial(ReadableInstant readableInstant){

		DateTime dt = readableInstant.toInstant().toDateTime();

		LocalDate ld = dt.toLocalDate();

		Partial partial = new Partial(ld);

		return partial;

	}

	/**

	 * Constructor

	 */

	protected TimePeriod() {

		super();

	}

	public TimePeriod(Partial startDate) {

		start=startDate;

	}

	public TimePeriod(Partial startDate, Partial endDate) {

		start=startDate;

		end=endDate;

	}

	/**

	 * True, if this time period represents a period not a single point in time.

	 * This is by definition, that the time period has a start and an end value,

	 * and both have a year value that is not null

	 * @return

	 */

	@Transient

	public boolean isPeriod(){

		if (getStartYear() != null && getEndYear() != null ){

			return true;

		}else{

			return false;

		}

	}

	/**

	 * True, if there is no start date and no end date and no freetext representation exists.

	 * @return

	 */

	@Transient

	public boolean isEmpty(){

		if (CdmUtils.isEmpty(this.getFreeText()) && start == null  && end == null ){

			return true;

		}else{

			return false;

		}

	}

	public Partial getStart() {

		return start;

	}

	public void setStart(Partial start) {

		this.start = start;

	}

	public Partial getEnd() {

		return end;

	}

	public void setEnd(Partial end) {

		this.end = end;

	}

	/**

	 * For time periods that need to store more information than the one

	 * that can be stored in <code>start</code> and <code>end</code>.

	 * If free text is not <code>null</null> {@link #toString()} will always

	 * return the free text value.

	 * <BR>Use {@link #toString()} for public use.

	 * @return the freeText

	 */

	public String getFreeText() {

		return freeText;

	}

	/**

	 * Use {@link #parseSingleDate(String)} for public use.

	 * @param freeText the freeText to set

	 */

	public void setFreeText(String freeText) {

		this.freeText = freeText;

	}

	@Transient

	public String getYear(){

		String result = "";

		if (getStartYear() != null){

			result += String.valueOf(getStartYear());

			if (getEndYear() != null){

				result += "-" + String.valueOf(getEndYear());

			}

		}else{

			if (getEndYear() != null){

				result += String.valueOf(getEndYear());

			}

		}

		return result;

	}

	@Transient

	public Integer getStartYear(){

		return getPartialValue(start, YEAR_TYPE);

	}

	@Transient

	public Integer getStartMonth(){

		return getPartialValue(start, MONTH_TYPE);

	}

	@Transient

	public Integer getStartDay(){

		return getPartialValue(start, DAY_TYPE);

	}

	@Transient

	public Integer getEndYear(){

		return getPartialValue(end, YEAR_TYPE);

	}

	@Transient

	public Integer getEndMonth(){

		return getPartialValue(end, MONTH_TYPE);

	}

	@Transient

	public Integer getEndDay(){

		return getPartialValue(end, DAY_TYPE);

	}

	public static Integer getPartialValue(Partial partial, DateTimeFieldType type){

		if (partial == null || ! partial.isSupported(type)){

			return null;

		}else{

			return partial.get(type);

		}

	}

	public TimePeriod setStartYear(Integer year){

		return setStartField(year, YEAR_TYPE);

	}

	public TimePeriod setStartMonth(Integer month) throws IndexOutOfBoundsException{

		return setStartField(month, MONTH_TYPE);

	}

	public TimePeriod setStartDay(Integer day) throws IndexOutOfBoundsException{

		return setStartField(day, DAY_TYPE);

	}

	public TimePeriod setEndYear(Integer year){

		return setEndField(year, YEAR_TYPE);

	}

	public TimePeriod setEndMonth(Integer month) throws IndexOutOfBoundsException{

		return setEndField(month, MONTH_TYPE);

	}

	public TimePeriod setEndDay(Integer day) throws IndexOutOfBoundsException{

		return setEndField(day, DAY_TYPE);

	}

	public static Partial setPartialField(Partial partial, Integer value, DateTimeFieldType type) 

			throws IndexOutOfBoundsException{

		if (partial == null){

			partial = new Partial();

		}

		if (value == null){

			return partial.without(type);

		}else{

			checkFieldValues(value, type, partial);

			return partial.with(type, value);

		}

	}

	private TimePeriod setStartField(Integer value, DateTimeFieldType type) 

			throws IndexOutOfBoundsException{

		start = setPartialField(start, value, type);

		return this;

	}

	private TimePeriod setEndField(Integer value, DateTimeFieldType type)

			throws IndexOutOfBoundsException{

		end = setPartialField(end, value, type);

		return this;

	}

	/**

	 * Throws an IndexOutOfBoundsException if the value does not have a valid value

	 * (e.g. month > 12, month < 1, day > 31, etc.)

	 * @param value

	 * @param type

	 * @throws IndexOutOfBoundsException

	 */

	private static void checkFieldValues(Integer value, DateTimeFieldType type, Partial partial)

			throws IndexOutOfBoundsException{

		int max = 9999999;

		if (type.equals(MONTH_TYPE)){

			max = 12;

		}

		if (type.equals(DAY_TYPE)){

			max = 31;

			Integer month = null;

			if (partial.isSupported(MONTH_TYPE)){

				month = partial.get(MONTH_TYPE);

			}

			if (month != null){

				if (month == 2){

					max = 29;

				}else if (month == 4 ||month == 6 ||month == 9 ||month == 11){

					max = 30; 

				}

			}

		}

		if ( (value < 1 || value > max) ){

			throw new IndexOutOfBoundsException("Value must be between 1 and " +  max);

		}

	}

	private void initStart(){

		if (start == null){

			start = new Partial();

		}

	}

	private void initEnd(){

		if (end == null){

			end = new Partial();

		}

	}

	//patter for first year in string;

	private static final Pattern firstYearPattern =  Pattern.compile("\\d{4}");

	//case "1806"[1807];

	private static final Pattern uncorrectYearPatter =  Pattern.compile("\"\\d{4}\"\\s*\\[\\d{4}\\]");

	//case fl. 1806 or c. 1806 or fl. 1806?

	private static final Pattern prefixedYearPattern =  Pattern.compile("(fl|c)\\.\\s*\\d{4}(\\s*-\\s*\\d{4})?\\??");

	//standard

	private static final Pattern standardPattern =  Pattern.compile("\\s*\\d{2,4}(\\s*-(\\s*\\d{2,4})?)?");

	private static final String strDotDate = "[0-3]?\\d\\.[01]?\\d\\.\\d{4,4}";

	private static final String strDotDatePeriodPattern = String.format("%s(\\s*-\\s*%s?)?", strDotDate, strDotDate);

	private static final Pattern dotDatePattern =  Pattern.compile(strDotDatePeriodPattern);

	public static TimePeriod parseString(TimePeriod timePeriod, String periodString){

		//TODO move to parser class

		//TODO until now only quick and dirty (and partly wrong)

		TimePeriod result = timePeriod;

		if(timePeriod == null){

			return timePeriod;

		}

		if (periodString == null){

			return result;

		}

		periodString = periodString.trim();

		result.setFreeText(null);

		Date date;

		//case "1806"[1807];

		if (uncorrectYearPatter.matcher(periodString).matches()){

			result.setFreeText(periodString);

			String realYear = periodString.split("\\[")[1];

			realYear = realYear.replace("]", "");

			result.setStartYear(Integer.valueOf(realYear));

			result.setFreeText(periodString);

		//case fl. 1806 or c. 1806 or fl. 1806?

		}else if(prefixedYearPattern.matcher(periodString).matches()){

			result.setFreeText(periodString);

			Matcher yearMatcher = firstYearPattern.matcher(periodString);

			yearMatcher.find();

			String startYear = yearMatcher.group();

			result.setStartYear(Integer.valueOf(startYear));

			if (yearMatcher.find()){

				String endYear = yearMatcher.group();

				result.setEndYear(Integer.valueOf(endYear));

			}

		}else if (dotDatePattern.matcher(periodString).matches()){

			parseDotDatePattern(periodString, result);

		}else if (standardPattern.matcher(periodString).matches()){

			parseStandardPattern(periodString, result);

//TODO first check ambiguity of parser results e.g. for 7/12/11 

//		}else if (isDateString(periodString)){

//			String[] startEnd = makeStartEnd(periodString);

//			String start = startEnd[0];

//			DateTime startDateTime = dateStringParse(start, true);

//			result.setStart(startDateTime);

//			if (startEnd.length > 1){

//				DateTime endDateTime = dateStringParse(startEnd[1], true);

//				;

//				result.setEnd(endDateTime.toLocalDate());

//			}

		}else{

			result.setFreeText(periodString);

		}

		return result;

	}

	private static boolean isDateString(String periodString) {

		String[] startEnd = makeStartEnd(periodString);

		String start = startEnd[0];

		DateTime startDateTime = dateStringParse(start, true);

		if (startDateTime == null){

			return false;

		}

		if (startEnd.length > 1){

			DateTime endDateTime = dateStringParse(startEnd[1], true);

			if (endDateTime != null){

				return true;

			}

		}

		return false;

	}

	/**

	 * @param periodString

	 * @return

	 */

	private static String[] makeStartEnd(String periodString) {

		String[] startEnd = new String[]{periodString};

		if (periodString.contains("-") && periodString.matches("^-{2,}-^-{2,}")){

			startEnd = periodString.split("-");

		}

		return startEnd;

	}

	private static DateTime dateStringParse(String string, boolean strict) {

		DateFormat dateFormat = DateFormat.getDateInstance();

		ParsePosition pos = new ParsePosition(0);

		Date a = dateFormat.parse(string, pos);

		if (a == null || pos.getIndex() != string.length()){

			return null;

		}

		Calendar cal = Calendar.getInstance();

		cal.setTime(a);

		DateTime result = new DateTime(cal);

		return result;

	}

	/**

	 * @param periodString

	 * @param result

	 */

	private static void parseDotDatePattern(String periodString,TimePeriod result) {

		String[] dates = periodString.split("-");

		Partial dtStart = null;

		Partial dtEnd = null;

		if (dates.length > 2 || dates.length <= 0){

			logger.warn("More than 1 '-' in period String: " + periodString);

			result.setFreeText(periodString);

		}else {

			try {

				//start

				if (! CdmUtils.isEmpty(dates[0])){

					dtStart = parseSingleDotDate(dates[0].trim());

				}

				//end

				if (dates.length >= 2 && ! CdmUtils.isEmpty(dates[1])){

					dtEnd = parseSingleDotDate(dates[1].trim());

				}

				result.setStart(dtStart);

				result.setEnd(dtEnd);

			} catch (IllegalArgumentException e) {

				//logger.warn(e.getMessage());

				result.setFreeText(periodString);

			}

		}

	}

	/**

	 * @param periodString

	 * @param result

	 */

	private static void parseStandardPattern(String periodString,

			TimePeriod result) {

		String[] years = periodString.split("-");

		Partial dtStart = null;

		Partial dtEnd = null;

		if (years.length > 2 || years.length <= 0){

			logger.warn("More than 1 '-' in period String: " + periodString);

		}else {

			try {

				//start

				if (! CdmUtils.isEmpty(years[0])){

					dtStart = parseSingleDate(years[0].trim());

				}

				//end

				if (years.length >= 2 && ! CdmUtils.isEmpty(years[1])){

					years[1] = years[1].trim();

					if (years[1].length()==2 && dtStart != null && dtStart.isSupported(DateTimeFieldType.year())){

						years[1] = String.valueOf(dtStart.get(DateTimeFieldType.year())/100) + years[1];

					}

					dtEnd = parseSingleDate(years[1]);

				}

				result.setStart(dtStart);

				result.setEnd(dtEnd);

			} catch (IllegalArgumentException e) {

				//logger.warn(e.getMessage());

				result.setFreeText(periodString);

			}

		}

	}

	public static TimePeriod parseString(String strPeriod) {

		TimePeriod timePeriod = TimePeriod.NewInstance();

		return parseString(timePeriod, strPeriod);

	}

	protected static Partial parseSingleDate(String singleDateString) throws IllegalArgumentException{

		//FIXME until now only quick and dirty and incomplete

		Partial partial =  new Partial();

		singleDateString = singleDateString.trim();

		if (CdmUtils.isNumeric(singleDateString)){

			try {

				Integer year = Integer.valueOf(singleDateString.trim());

				if (year < 1000 && year > 2100){

					logger.warn("Not a valid year: " + year + ". Year must be between 1000 and 2100");

				}else if (year < 1700 && year > 2100){

					logger.warn("Not a valid taxonomic year: " + year + ". Year must be between 1750 and 2100");

					partial = partial.with(YEAR_TYPE, year);

				}else{

					partial = partial.with(YEAR_TYPE, year);

				}

			} catch (NumberFormatException e) {

				logger.debug("Not a Integer format in getCalendar()");

				throw new IllegalArgumentException(e);

			}

		}else{

			throw new IllegalArgumentException("Until now only years can be parsed as single dates. But date is: " + singleDateString);

		}

		return partial;

	}

	protected static Partial parseSingleDotDate(String singleDateString) throws IllegalArgumentException{

		Partial partial =  new Partial();

		singleDateString = singleDateString.trim();

		String[] split = singleDateString.split("\\.");

		int length = split.length;

		if (length > 3){

			throw new IllegalArgumentException(String.format("More than 2 dots in date '%s'", singleDateString));

		}

		String strYear = split[split.length-1];

		String strMonth = length >= 2? split[split.length-2]: null;

		String strDay = length >= 3? split[split.length-3]: null;

		try {

			Integer year = Integer.valueOf(strYear.trim());

			Integer month = Integer.valueOf(strMonth.trim());

			Integer day = Integer.valueOf(strDay.trim());

			if (year < 1000 && year > 2100){

				logger.warn("Not a valid year: " + year + ". Year must be between 1000 and 2100");

			}else if (year < 1700 && year > 2100){

				logger.warn("Not a valid taxonomic year: " + year + ". Year must be between 1750 and 2100");

				partial = partial.with(YEAR_TYPE, year);

			}else{

				partial = partial.with(YEAR_TYPE, year);

			}

			if (month != null && month != 0){

				partial = partial.with(MONTH_TYPE, month);

			}

			if (day != null && day != 0){

				partial = partial.with(DAY_TYPE, day);

			}

		} catch (NumberFormatException e) {

			logger.debug("Not a Integer format somewhere in " + singleDateString);

			throw new IllegalArgumentException(e);

		}

		return partial;

	}

	private class TimePeriodPartialFormatter extends DateTimeFormatter{

		private TimePeriodPartialFormatter(){

			super(null, null);

		}

		public String print(ReadablePartial partial){

			//TODO

			String result = "";

			String year = (partial.isSupported(YEAR_TYPE))? String.valueOf(partial.get(YEAR_TYPE)):null;

			String month = (partial.isSupported(MONTH_TYPE))? String.valueOf(partial.get(MONTH_TYPE)):null;;

			String day = (partial.isSupported(DAY_TYPE))? String.valueOf(partial.get(DAY_TYPE)):null;;

			if (month !=null){

				if (year == null){

					year = "xxxx";

				}

			}

			if (day != null){

				if (month == null){

					month = "xx";

				}

				if (year == null){

					year = "xxxx";

				}

			}

			result = (day != null)? day + "." : "";

			result += (month != null)? month + "." : "";

			result += (year != null)? year : "";

			return result;

		}

	}

//**************************** to String ****************************************	

	/** 

	 * Returns the {@link #getFreeText()} value if free text is not <code>null</code>.

	 * Otherwise the concatenation of <code>start</code> and <code>end</code> is returned. 

	 * 

	 * @see java.lang.Object#toString()

	 */

	public String toString(){

		String result = null;

		DateTimeFormatter formatter = new TimePeriodPartialFormatter();

		if ( CdmUtils.isNotEmpty(this.getFreeText())){

			result = this.getFreeText();

		}else{

			String strStart = start != null ? start.toString(formatter): null;

			String strEnd = end != null ? end.toString(formatter): null;

			result = CdmUtils.concat("-", strStart, strEnd);

		}

		return result;

	}

//*********** EQUALS **********************************/	

	/* (non-Javadoc)

	 * @see java.lang.Object#equals(java.lang.Object)

	 */

	@Override

	public boolean equals(Object obj) {

		if (obj == null){

			return false;

		}

		if (! (obj instanceof TimePeriod)){

			return false;

		}

		TimePeriod that = (TimePeriod)obj;

		if (! CdmUtils.nullSafeEqual(this.start, that.start)){

			return false;

		}

		if (! CdmUtils.nullSafeEqual(this.end, that.end)){

			return false;

		}

		if (! CdmUtils.nullSafeEqual(this.freeText, that.freeText)){

			return false;

		}

		return true;

	}

	/* (non-Javadoc)

	 * @see java.lang.Object#hashCode()

	 */

	@Override

	public int hashCode() {

		int hashCode = 7;

		hashCode = 29*hashCode +  

					(start== null? 33: start.hashCode()) + 

					(end== null? 39: end.hashCode()) + 

					(freeText== null? 41: freeText.hashCode()); 

		return super.hashCode();

	}	

//*********** CLONE **********************************/	

	/* (non-Javadoc)

	 * @see java.lang.Object#clone()

	 */

	@Override

	public Object clone()  {

		try {

			TimePeriod result = (TimePeriod)super.clone();

			result.setStart(this.start);   //DateTime is immutable

			result.setEnd(this.end);	

			result.setFreeText(this.freeText);

			return result;

		} catch (CloneNotSupportedException e) {

			logger.warn("Clone not supported exception. Should never occurr !!");

			return null;

		}

	}

}