package at.gv.egovernment.moa.id.auth.parser;

import java.io.IOException;

import at.gv.egovernment.moa.id.ParseException;
import at.gv.egovernment.moa.util.Base64Utils;

/**
 * Parser for a SAML artifact.
 * @author Paul Ivancsics
 * @version $Id$
 */
public class SAMLArtifactParser {
  /** byte array containing the SamlArtifact bytes */
  private byte[] samlArtifactBytes;

  /**
   * Constructor
   * @param samlArtifact as String
   * @throws ParseException on any parsing error
   */
  public SAMLArtifactParser(String samlArtifact) throws ParseException {
    try {
      samlArtifactBytes = Base64Utils.decode(samlArtifact, false);
    }
    catch (IOException ex) {
      throw new ParseException("parser.02", new Object[] {ex.toString()}, ex);
    }
  }
  /**
   * Parses the type code.
   * @return type code
   * @throws ParseException when SAML artifact is invalid
   */
  public byte[] parseTypeCode() throws ParseException {
    try {
      byte[] typeCode = new byte[] {samlArtifactBytes[0], samlArtifactBytes[1]};
      return typeCode;
    }
    catch (Throwable ex) {
      throw new ParseException("parser.02", new Object[] {ex.toString()}, ex);
    }
  }
  /**
   * Parses the assertion handle.
   * @return assertion handle
   * @throws ParseException when SAML artifact is invalid
   */
  public String parseAssertionHandle() throws ParseException {
    try {
      return new String(samlArtifactBytes, 22, 20);
    }
    catch (Throwable ex) {
      throw new ParseException("parser.02", new Object[] {ex.toString()}, ex);
    }
  }

}