package ixa.kaflib;
   
   import java.util.regex.Matcher;
   import java.util.regex.Pattern;
   
   /**
    * Created with IntelliJ IDEA.
    * User: alessio
    * Date: 07/08/14
   * Time: 21:41
   * To change this template use File | Settings | File Templates.
   */
  
  public class GenericId {
  	private String prefix;
  	private int counter = 0;
  	private boolean inconsistent = false;
  
  	public String getNext() {
  		if (inconsistent) {
  			throw new IllegalStateException("Inconsistent WF IDs. Can't create new WF IDs.");
  		}
  		return prefix + Integer.toString(++counter);
  	}
  
  	public void update(String id) {
  		try {
  			Integer idNum = extractCounterFromId(id);
  			if (counter < idNum) {
  				counter = idNum;
  			}
  		} catch (IllegalStateException e) {
  			inconsistent = true;
  		}
  	}
  
  	GenericId(String prefix) {
  		this.prefix = prefix;
  	}
  
  	private static int extractCounterFromId(String id) {
  		Matcher matcher = Pattern.compile("\\d+$").matcher(id);
  		if (!matcher.find()) {
  			throw new IllegalStateException("GenericId doesn't recognise the given id's (" + id + ") format.");
  		}
  		return Integer.valueOf(matcher.group(0));
  	}
  
  	public String getPrefix() {
  		return prefix;
  	}
  }