/*
   Copyright (C) 2005-2012, by the President and Fellows of Harvard College.

   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.

   Dataverse Network - A web application to share, preserve and analyze research data.
   Developed at the Institute for Quantitative Social Science, Harvard University.
   Version 3.0.
*/
/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package edu.harvard.iq.dvn.core.web.util;

import edu.harvard.iq.dvn.core.util.StringUtil;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

/**
 *
 * @author Ellen Kraffmiller
 */
public class DvnDate {
    String year;
    String month;
    String day;
    String era;
    String errMessage;
    
    DvnDate( String formattedDate ) {
        setDateParts(formattedDate);
                
        
    }
    private boolean validate() {
      
        errMessage=null;
        
        // If day is set, then month and year must be set
        if (!StringUtil.isEmpty(day)) {
            if (StringUtil.isEmpty(month) || StringUtil.isEmpty(year)) {
                errMessage="If day is entered, then month and year must be entered.";
                return false;
            }
        }
        // If month is set, then year must be set
        if (!StringUtil.isEmpty(month)) {
            if ( StringUtil.isEmpty(year)) {
                errMessage="If month is entered, then year must be entered.";
                return false;
            }
        }
      //  if (convertStringToDate(getDateString())==null) {
      //      errMessage="Invalid date.";
      //  }
        return true;
    }
    
    private void setDateParts(String formattedDate) {
        Date date = convertStringToDate(formattedDate);
        if (date!=null) {
            Calendar calendar = Calendar.getInstance();
            calendar.setTime(date);
            year = new Integer(calendar.get(Calendar.YEAR)).toString();
            month = new Integer(calendar.get(Calendar.MONTH)+1).toString();
            day = new Integer(calendar.get(Calendar.DAY_OF_MONTH)).toString();
            int eraInt = calendar.get(Calendar.ERA);
            if (eraInt==0) {
                era="BC";
            }       
        }
        else {
            // we couldn't separate date into it's component parts, 
            // so put it all in year.
            year= formattedDate;
        }
    }
    
    public static Date convertStringToDate(String dateString) {
          Date date = convertFromPattern(dateString,"yyyy-MM-dd");
        if (date==null ) {
            date = convertFromPattern(dateString, "yyyy-MM");
        }
         if (date==null) {
            date = convertFromPattern(dateString,"yyyy GG");
        }
        if (date==null) {
            date = convertFromPattern(dateString,"yyyyGG");
        }
        if (date==null) {
            date = convertFromPattern(dateString,"yyyy");
        }
        return date;
    }
    public static Date convertFromPattern(String dateString, String pattern) {
        if( dateString == null)
            return null;
        Date date=null;
        SimpleDateFormat sdf = new SimpleDateFormat(pattern);
        sdf.setLenient(false);
        
        
        try {
            dateString = dateString.trim();
            date = sdf.parse(dateString);
            Calendar calendar = Calendar.getInstance();
            calendar.setTime(date);
            int year = calendar.get(Calendar.YEAR);
          //  System.out.println("pattern is "+ pattern);
          //  System.out.println("Year is "+year);
          //  System.out.println("Calendar date is "+date.toString());
          //  System.out.println("Era is "+calendar.get(Calendar.ERA));
        } catch(ParseException e) {
            date=null;
        }
        if (dateString.length()>pattern.length()) {
          date=null;
        }
        return date;
    }
     
     public String toString() {
         String str = new String();
         str = "Year: "+year+"; Month: "+month+", Day: "+day+"; Era: "+era;
         return str;
     }
     
     public static void main(String args[]) {
         String testString ="2008 BC";
         System.out.println("Testing: "+testString);
         DvnDate dvnDate = new DvnDate(testString);
         System.out.println(dvnDate);
     }

}