/**
 * 
 */
package uk.ac.vamsas.client;

import java.net.URI;
import java.util.Hashtable;

/**
 * @author jimp
 * base class for vamsas session/document types
 * uses java.net.URI internally for construction of URN
 */
public abstract class SessionUrn {
  protected URI urn;
  /**
   * The types of URI protocols we understand
   */
  protected static final Hashtable TYPES=new Hashtable();
  
  
  protected SessionUrn()
  {
    //
  }
  /**
   * construct urn for a locally stored session file
   * @param type
   * @param url
   */
  protected SessionUrn(String type, java.net.URL url) {
    if (!TYPES.containsKey(type.toLowerCase()))
      throw new Error("Unknown "+this.getClass().getName()+" type '"+type+"' for URL '"+url+"'");
    try {
      
        this.setURN(type+"://"+url.getPath());
    //  urn = URI.create(type+"://"+url.getPath());
    } catch (Exception e) {
      // TODO: something better than throwing an error should be done here.
      e.printStackTrace(System.err);
      throw new Error(e);
    }
  }
  
  protected SessionUrn(String type, URI uri) {
    if (!TYPES.containsKey(type.toLowerCase()))
      throw new Error("Unknown "+this.getClass().getName()+" type '"+type+"' for URI '"+uri+"'");
    try {
      //  this.setURN(type+"://"+uri.getPath());
      //bad hack but should do the trick
      this.setURN(type+"://"+uri.getRawPath());
   } catch (Exception e) {
      // TODO: something better than throwing an error should be done here.
      e.printStackTrace(System.err);
      throw new Error(e);
    }
  }
  
  public String getSessionUrn() {
    return this.urn.toString();
  }
  
  /**
   * Set the urn attribute
   * create a URI from the provided String
   * 
   * @param urnString urn to convert to a URN
   */
  protected void setURN(String urnString) throws    InvalidSessionUrnException// NullPointerException, IllegalArgumentException 
    {
      try {
        this.urn = URI.create(urnString);
      } catch (Exception e) {
        throw new InvalidSessionUrnException(e);
      }
    }
  
}