/**
 * <copyright> Copyright 2006 by Know-Center, Graz, Austria </copyright>
 * PDF-AS has been contracted by the E-Government Innovation Center EGIZ, a
 * joint initiative of the Federal Chancellery Austria and Graz University of
 * Technology.
 *
 * Licensed under the EUPL, Version 1.1 or - as soon they will be approved by
 * the European Commission - subsequent versions of the EUPL (the "Licence");
 * You may not use this work except in compliance with the Licence.
 * You may obtain a copy of the Licence at:
 * http://www.osor.eu/eupl/
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the Licence is distributed on an "AS IS" basis,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the Licence for the specific language governing permissions and
 * limitations under the Licence.
 *
 * This product combines work with different licenses. See the "NOTICE" text
 * file for details on the various modules and licenses.
 * The "NOTICE" text file is part of the distribution. Any derivative works
 * that you distribute must include a readable copy of the "NOTICE" text file.
 *
 * $Id: PdfASID.java,v 1.1 2006/08/25 17:04:16 wprinz Exp $
 */
package at.knowcenter.wag.egov.egiz;

import java.io.Serializable;

import at.gv.egiz.pdfas.exceptions.ErrorCode;
import at.knowcenter.wag.egov.egiz.exceptions.InvalidIDException;
import at.knowcenter.wag.egov.egiz.framework.SignatorFactory;

/**
 * This class encapsulates the Pdf-AS ID ("Kennzeichnung") urn.
 * 
 * @author wprinz
 */
public class PdfASID implements Serializable
{

  /**
   * SVUID.
   */
  private static final long serialVersionUID = 4776635173830445739L;

  /**
   * The urn word that leads in the identifier.
   */
  protected static final String URN = "urn";

  /**
   * The namespace of the urn.
   */
  protected static final String NAMESPACE = "pdfsigfilter";

  /**
   * The separator between urn blocks.
   */
  protected static final String SPLIT_STRING = ":";

  /**
   * The vendor.
   */
  protected String vendor = null;

  /**
   * The algorithm type.
   */
  protected String type = null;

  /**
   * The version of the algorithm.
   */
  protected String version = null;

  /**
   * Constructor that fills in the parameters directly.
   * 
   * @param vendor
   * @param type
   * @param version
   */
  public PdfASID(String vendor, String type, String version)
  {
    set(vendor, type, version);
  }

  /**
   * Parses the given id String and throws an Exception if it is not valid.
   * 
   * @param id
   *          The id String to be parsed.
   */
  public PdfASID(String id) throws InvalidIDException
  {
    String[] tokens = id.split(SPLIT_STRING);

    if (tokens.length != 5)
    {
      throw new InvalidIDException(ErrorCode.UNABLE_TO_PARSE_ID, "The method doesn't have enough tokens (" + id + ")");
    }

    if (!tokens[0].equals(URN))
    {
      throw new InvalidIDException(ErrorCode.UNABLE_TO_PARSE_ID, "The method must start with " + URN + " (" + id + ")");
    }

    if (!tokens[1].equals(NAMESPACE))
    {
      throw new InvalidIDException(ErrorCode.UNABLE_TO_PARSE_ID, "The namespace of the method must be " + NAMESPACE + " (" + id + ")");
    }

    set(tokens[2], tokens[3], tokens[4]);
  }

  /**
   * Copy Constructor.
   * 
   * @param other
   *          The other PdfASID to copy the data from.
   */
  public PdfASID(final PdfASID other)
  {
    set(other.vendor, other.type, other.version);
  }

  /**
   * Auxiliary constructor.
   * 
   * @param vendor
   *          The vendor.
   * @param type
   *          The type.
   * @param version
   *          The version.
   */
  private void set(String vendor, String type, String version)
  {
    this.vendor = vendor;
    this.type = type;
    this.version = version;
  }

  /**
   * Returns the type.
   * 
   * @return Returns the type.
   */
  public String getType()
  {
    return this.type;
  }

  /**
   * Returns the vendor.
   * 
   * @return Returns the vendor.
   */
  public String getVendor()
  {
    return this.vendor;
  }

  /**
   * Returns the version.
   * 
   * @return Returns the version.
   */
  public String getVersion()
  {
    return this.version;
  }
  
  

  /**
   * @see java.lang.Object#equals(java.lang.Object)
   */
  //@override
  public boolean equals(Object obj)
  {
    if (obj == null)
    {
      return false;
    }
    if (!(obj instanceof PdfASID))
    {
      return false;
    }
    
    PdfASID other = (PdfASID) obj;
    
    return this.toString().equals(other.toString());
  }

  /**
   * @see java.lang.Object#hashCode()
   */
  public int hashCode()
  {
    return toString().hashCode();
  }

  /**
   * @see java.lang.Object#toString()
   */
  public String toString()
  {
    return URN + SPLIT_STRING + NAMESPACE + SPLIT_STRING + this.vendor + SPLIT_STRING + this.type + SPLIT_STRING + this.version;
  }
  
  /**
   * Returns if it is an old textual signature (pre 1.2.0) that used cp1252 encoding for text extraction (mostly)
   * @return
   */
  public boolean isOldCp1252Version() {     
     return this.getVersion().equals(SignatorFactory.VERSION_1_0_0) 
        || this.getVersion().equals(SignatorFactory.VERSION_1_1_0);
  }

}