/**
 * 
 */
package at.knowcenter.wag.egov.egiz.sig.connectors.moa;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.security.cert.CertificateException;
import java.security.cert.CertificateFactory;
import java.security.cert.X509Certificate;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import at.knowcenter.wag.egov.egiz.exceptions.ConnectorException;
import at.knowcenter.wag.egov.egiz.sig.SignatureObject;
import at.knowcenter.wag.egov.egiz.sig.X509Cert;
import at.knowcenter.wag.egov.egiz.sig.connectors.bku.BKUHelper;
import at.knowcenter.wag.egov.egiz.sig.connectors.bku.SignSignatureObject;
import at.knowcenter.wag.egov.egiz.sig.sigid.IdFormatter;
import at.knowcenter.wag.egov.egiz.tools.CodingHelper;

/**
 * @author wprinz
 * 
 */
public class MOAHelper
{
  /**
   * The log.
   */
  private static Log log = LogFactory.getLog(MOAHelper.class);

  /**
   * This method parses the MOA-Response string.
   * 
   * <p>
   * It separates the SignatureValue, X509IssuerName, SigningTime,
   * X509SerialNumber, X509Certificate, CertDigest and DigestValues. If the
   * X509Certificate is extracted it would be stored in the certificates
   * directory.
   * </p>
   * 
   * @param xmlResponse
   *          the response string from the MOA sign-request
   * @throws ConnectorException
   *           ErrorCode (303, 304)
   * @see SignatureObject
   * @see CodingHelper
   * @see X509Cert
   */
  public static SignSignatureObject parseCreateXMLResponse(String xmlResponse, IdFormatter id_formatter) throws ConnectorException
  {
    Pattern sig_val_p_s = Pattern.compile("<[\\w]*:?SignatureValue>"); //$NON-NLS-1$
    Pattern sig_val_p_e = Pattern.compile("</[\\w]*:?SignatureValue>"); //$NON-NLS-1$
    Pattern iss_nam_p_s = Pattern.compile("<[\\w]*:?X509IssuerName>"); //$NON-NLS-1$
    Pattern iss_nam_p_e = Pattern.compile("</[\\w]*:?X509IssuerName>"); //$NON-NLS-1$
    Pattern sig_tim_p_s = Pattern.compile("<[\\w]*:?SigningTime>"); //$NON-NLS-1$
    Pattern sig_tim_p_e = Pattern.compile("</[\\w]*:?SigningTime>"); //$NON-NLS-1$
    Pattern ser_num_p_s = Pattern.compile("<[\\w]*:?X509SerialNumber>"); //$NON-NLS-1$
    Pattern ser_num_p_e = Pattern.compile("</[\\w]*:?X509SerialNumber>"); //$NON-NLS-1$
    Pattern sig_cer_p_s = Pattern.compile("<[\\w]*:?X509Certificate>"); //$NON-NLS-1$
    Pattern sig_cer_p_e = Pattern.compile("</[\\w]*:?X509Certificate>"); //$NON-NLS-1$

    // Pattern sig_cer_d_p_s = Pattern.compile("<[\\w]*:?CertDigest>");
    // //$NON-NLS-1$
    // Pattern sig_cer_d_p_e = Pattern.compile("</[\\w]*:?CertDigest>");
    // //$NON-NLS-1$
    // Pattern dig_val_p_s = Pattern.compile("<[\\w]*:?DigestValue>");
    // //$NON-NLS-1$
    // Pattern dig_val_p_e = Pattern.compile("</[\\w]*:?DigestValue>");
    // //$NON-NLS-1$

    Matcher sig_val_m_s = sig_val_p_s.matcher(xmlResponse);
    Matcher sig_val_m_e = sig_val_p_e.matcher(xmlResponse);
    Matcher iss_nam_m_s = iss_nam_p_s.matcher(xmlResponse);
    Matcher iss_nam_m_e = iss_nam_p_e.matcher(xmlResponse);
    Matcher sig_tim_m_s = sig_tim_p_s.matcher(xmlResponse);
    Matcher sig_tim_m_e = sig_tim_p_e.matcher(xmlResponse);
    Matcher ser_num_m_s = ser_num_p_s.matcher(xmlResponse);
    Matcher ser_num_m_e = ser_num_p_e.matcher(xmlResponse);
    Matcher sig_cer_m_s = sig_cer_p_s.matcher(xmlResponse);
    Matcher sig_cer_m_e = sig_cer_p_e.matcher(xmlResponse);

    // Matcher sig_cer_d_m_s = sig_cer_d_p_s.matcher(xmlResponse);
    // Matcher sig_cer_d_m_e = sig_cer_d_p_e.matcher(xmlResponse);
    // Matcher dig_val_m_s = dig_val_p_s.matcher(xmlResponse);
    // Matcher dig_val_m_e = dig_val_p_e.matcher(xmlResponse);

    // SignatureValue
    String sig_val = null;
    if (sig_val_m_s.find() && sig_val_m_e.find())
    {
      sig_val = BKUHelper.removeAllWhitespace(xmlResponse.substring(sig_val_m_s.end(), sig_val_m_e.start()));
    }
    log.debug("sig_val = " + sig_val); //$NON-NLS-1$

    // X509IssuerName
    String iss_nam = null;
    if (iss_nam_m_s.find() && iss_nam_m_e.find())
    {
      iss_nam = xmlResponse.substring(iss_nam_m_s.end(), iss_nam_m_e.start());
    }
    log.debug("iss_nam = " + iss_nam); //$NON-NLS-1$

    // X509SerialNumber
    String ser_num = null;
    if (ser_num_m_s.find() && ser_num_m_e.find())
    {
      ser_num = BKUHelper.removeAllWhitespace(xmlResponse.substring(ser_num_m_s.end(), ser_num_m_e.start()));
    }
    log.debug("ser_num = " + ser_num); //$NON-NLS-1$

    // SigningTime
    String sig_tim = null;
    if (sig_tim_m_s.find() && sig_tim_m_e.find())
    {
      sig_tim = xmlResponse.substring(sig_tim_m_s.end(), sig_tim_m_e.start());
    }
    log.debug("sig_tim = " + sig_tim); //$NON-NLS-1$

    // CertDigest
    // if (sig_cer_d_m_s.find() && sig_cer_d_m_e.find())
    // {
    // String cert_digest = xmlResponse.substring(sig_cer_d_m_s.end(),
    // sig_cer_d_m_e.start());
    // if (dig_val_m_s.find() && dig_val_m_e.find())
    // {
    // sig_dig = cert_digest.substring(dig_val_m_s.end(), dig_val_m_e.start());
    // //sigObj.setX509CertificateDigest(sig_dig);
    // }
    // }

    // X509Certificate
    X509Certificate cert = null;
    if (sig_cer_m_s.find() && sig_cer_m_e.find())
    {
      String sig_cer = BKUHelper.removeAllWhitespace(xmlResponse.substring(sig_cer_m_s.end(), sig_cer_m_e.start()));

      try
      {
        byte[] der = CodingHelper.decodeBase64(sig_cer);
        ByteArrayInputStream bais = new ByteArrayInputStream(der);
        CertificateFactory cf = CertificateFactory.getInstance("X.509"); //$NON-NLS-1$
        cert = (X509Certificate) cf.generateCertificate(bais);
        bais.close();
      }
      catch (UnsupportedEncodingException e)
      {
        log.error(e);
        throw new ConnectorException(300, e);
      }
      catch (CertificateException e)
      {
        log.error(e);
        throw new ConnectorException(300, e);
      }
      catch (IOException e)
      {
        log.error(e);
        throw new ConnectorException(300, e);
      }
    }
    log.debug("X509Certificate = " + cert); //$NON-NLS-1$

    if (log.isDebugEnabled())
    {

      String cert_iss = cert.getIssuerDN().getName();
      log.debug("certificate's issuer = " + cert_iss); //$NON-NLS-1$
      log.debug("response's issuer    = " + iss_nam); //$NON-NLS-1$
      log.debug("issuer matches = " + cert_iss.equals(iss_nam)); //$NON-NLS-1$
      log.debug("ser number matches = " + cert.getSerialNumber().toString().equals(ser_num)); //$NON-NLS-1$
    }

    SignSignatureObject so = new SignSignatureObject();
    so.date = sig_tim;
    so.issuer = iss_nam;
    so.signatureValue = sig_val;
    so.x509Certificate = cert;

    so.id = id_formatter.formatIds(null);

    return so;
  }

}