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

import java.security.cert.X509Certificate;
import java.util.Properties;

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

import at.knowcenter.wag.egov.egiz.cfg.SettingsReader;
import at.knowcenter.wag.egov.egiz.exceptions.ConnectorException;
import at.knowcenter.wag.egov.egiz.exceptions.SettingsException;
import at.knowcenter.wag.egov.egiz.exceptions.SignatureException;
import at.knowcenter.wag.egov.egiz.sig.SignatureData;
import at.knowcenter.wag.egov.egiz.sig.SignatureResponse;
import at.knowcenter.wag.egov.egiz.sig.connectors.Connector;
import at.knowcenter.wag.egov.egiz.sig.connectors.TemplateReplaces;
import at.knowcenter.wag.egov.egiz.sig.connectors.bku.BKUHelper;
import at.knowcenter.wag.egov.egiz.sig.connectors.bku.BKUPostConnection;
import at.knowcenter.wag.egov.egiz.sig.connectors.bku.DetachedBKUConnector;
import at.knowcenter.wag.egov.egiz.sig.connectors.bku.SignSignatureObject;
import at.knowcenter.wag.egov.egiz.sig.sigid.DetachedLocRefMOAIdFormatter;
import at.knowcenter.wag.egov.egiz.sig.sigkz.SigKZIDHelper;
import at.knowcenter.wag.egov.egiz.tools.CodingHelper;
import at.knowcenter.wag.egov.egiz.tools.DebugHelper;
import at.knowcenter.wag.egov.egiz.tools.FileHelper;

/**
 * Connects to MOA providing the Data detached as LocRef on a local resource.
 * 
 * @author wprinz
 */
public class DetachedLocRefMOAConnector implements Connector
{
  /**
   * The SIG_ID prefix.
   */
  // public static final String SIG_ID_PREFIX = "etsi-bku-detached@"; //$NON-NLS-1$

  /**
   * The log.
   */
  private static Log log = LogFactory.getLog(DetachedLocRefMOAConnector.class);

  /**
   * The environemnt configuration of this connector containing templates and
   * other configurable elements.
   */
  protected Environment environment = null;

  /**
   * Constructor that builds the configuration environment for this connector
   * according to the given profile.
   * 
   * <p>
   * If confuguration parameters are not defined on that profile, the default
   * parameters defined in the configuration are used.
   * </p>
   * 
   * @param profile
   *          The profile from which the Environment should be assembled.
   * @throws SettingsException
   *           f.e.
   * @throws SignatureException
   *           f.e.
   */
  public DetachedLocRefMOAConnector(String profile, String signature_data_url) throws ConnectorException
  {
    this.environment = new Environment(profile, signature_data_url);
  }

  protected String prepareSignRequest(SignatureData data) throws ConnectorException
  {
    log.debug("prepareSignRequestDetached:"); //$NON-NLS-1$

    String sign_request_template = this.environment.getSignRequestTemplate();

    String sign_key_identifier = this.environment.getSignKeyIdentifier();
    String loc_ref_content = this.environment.getSignatureDataUrl();
    String mime_type = data.getMimeType();
    if (log.isDebugEnabled())
    {
      log.debug("sign keybox identifier = " + sign_key_identifier); //$NON-NLS-1$
      log.debug("LocRefContent = " + loc_ref_content); //$NON-NLS-1$
      log.debug("mime type = " + mime_type); //$NON-NLS-1$
    }

    String sign_request_xml = sign_request_template.replaceFirst(TemplateReplaces.KEY_IDENTIFIER_REPLACE, sign_key_identifier);
    sign_request_xml = sign_request_xml.replaceFirst(TemplateReplaces.LOC_REF_CONTENT_REPLACE, loc_ref_content);
    sign_request_xml = sign_request_xml.replaceFirst(TemplateReplaces.MIME_TYPE_REPLACE, mime_type);

    log.debug("prepareSignRequestDetached finished."); //$NON-NLS-1$
    return sign_request_xml;
  }

  /**
   * @see at.knowcenter.wag.egov.egiz.sig.connectors.LocalConnector#analyzeSignResponse(java.util.Properties)
   */
  public SignSignatureObject analyzeSignResponse(Properties response_properties) throws ConnectorException
  {
    log.debug("analyzeSignResponse:"); //$NON-NLS-1$

    String response_string = response_properties.getProperty(BKUPostConnection.RESPONSE_STRING_KEY);

    BKUHelper.checkResponseForError(response_string);

    SignSignatureObject so = MOAHelper.parseCreateXMLResponse(response_string, new DetachedLocRefMOAIdFormatter());

    log.debug("analyzeSignResponse finished."); //$NON-NLS-1$
    return so;
  }

  /**
   * @see at.knowcenter.wag.egov.egiz.sig.connectors.Connector#doSign(at.knowcenter.wag.egov.egiz.sig.SignatureData)
   */
  public SignSignatureObject doSign(SignatureData data) throws ConnectorException
  {
    log.debug("doSign:"); //$NON-NLS-1$

    String sign_request_xml = prepareSignRequest(data);
//    DebugHelper.debugStringToFile(sign_request_xml, "MOA_DetLocRef_sign_request.xml"); //$NON-NLS-1$

    String url = this.environment.getSignURL();
    Properties response_properties = sendRequest(url, MOASoapConnection.SERVICE_SIGN, sign_request_xml);

//    DebugHelper.debugStringToFile(response_properties.getProperty(BKUPostConnection.RESPONSE_STRING_KEY), "MOA_DetLocRef_sign_response.xml"); //$NON-NLS-1$
    SignSignatureObject sso = analyzeSignResponse(response_properties);

    // TODO this could be made more generic
    sso.response_properties = response_properties;

    log.debug("doSign finished."); //$NON-NLS-1$
    return sso;
  }

  /**
   * @see at.knowcenter.wag.egov.egiz.sig.connectors.Connector#doVerify(at.knowcenter.wag.egov.egiz.sig.SignatureData,
   *      at.knowcenter.wag.egov.egiz.sig.connectors.bku.SignSignatureObject)
   */
  public SignatureResponse doVerify(SignatureData data, SignSignatureObject so) throws ConnectorException
  {
    log.debug("doVerify:"); //$NON-NLS-1$

    String verify_request_xml = prepareVerifyRequest(data, so);
    log.debug("verify_request_xml = " + verify_request_xml); //$NON-NLS-1$

    String url = this.environment.getVerifyURL();
    Properties response_properties = sendRequest(url, MOASoapConnection.SERVICE_VERIFY, verify_request_xml);

    SignatureResponse signature_response = analyzeVerifyResponse(response_properties);

    log.debug("doVerify finished."); //$NON-NLS-1$
    return signature_response;
  }

  /**
   * Prepares the verify request xml to be sent using the verify request
   * template.
   * 
   * @param data
   *          The SignatureData.
   * @param so
   *          The signature information object.
   * @return Returns the verify request xml to be sent.
   * @throws ConnectorException
   *           f.e.
   */
  public String prepareVerifyRequest(SignatureData data, SignSignatureObject so) throws ConnectorException
  {
    String verify_request_template = this.environment.getVerifyRequestTemplate();

    String xml_content = null;
    if (!SigKZIDHelper.isMOASigned(so))
    {
      DetachedBKUConnector bku_connector = new DetachedBKUConnector(this.environment.getProfile(), "not needed here");
      xml_content = bku_connector.prepareXMLContent(data, so);
    }
    else
    {
      xml_content = prepareXMLContent(data, so);
    }

    String verify_request_xml = verify_request_template.replaceFirst(TemplateReplaces.XML_CONTENT_REPLACE, xml_content);
    verify_request_xml = verify_request_xml.replaceFirst(TemplateReplaces.TRUST_PROFILE_ID_REPLACE, this.environment.getVerifyTrustProfileId());
    verify_request_xml = verify_request_xml.replaceFirst(TemplateReplaces.LOC_REF_CONTENT_REPLACE, this.environment.getSignatureDataUrl());

    return verify_request_xml;
  }

  /**
   * Analyzes the verify response string.
   * 
   * @param response_properties
   *          The response properties containing the response XML.
   * @return Returns the SignatureResponse containing the verification result.
   * @throws ConnectorException
   *           f.e.
   */
  public SignatureResponse analyzeVerifyResponse(Properties response_properties) throws ConnectorException
  {
    log.debug("analyzeVerifyResponse:"); //$NON-NLS-1$

    String response_string = response_properties.getProperty(BKUPostConnection.RESPONSE_STRING_KEY);

    BKUHelper.checkResponseForError(response_string);

    SignatureResponse signature_response = BKUHelper.parseVerifyXMLResponse(response_string);

    log.debug("analyzeVerifyResponse finished."); //$NON-NLS-1$
    return signature_response;
  }

  public String prepareXMLContent(SignatureData data, SignSignatureObject so) throws ConnectorException
  {
    log.debug("prepareXMLContent:"); //$NON-NLS-1$
    try
    {

      String verify_template = this.environment.getVerifyTemplate();

      X509Certificate cert = so.getX509Certificate();
      String cert_alg = this.environment.getCertAlgEcdsa();
      if (cert.getPublicKey().getAlgorithm().indexOf("RSA") >= 0) //$NON-NLS-1$
      {
        cert_alg = this.environment.getCertAlgRsa();
      }

      // cert alg replace
      String verify_xml = verify_template.replaceFirst(TemplateReplaces.CERT_ALG_REPLACE, cert_alg);

      // data digest replace
      {
        byte[] data_value = data.getData();
        byte[] data_value_hash = CodingHelper.buildDigest(data_value);
        String object_data_hash = CodingHelper.encodeBase64(data_value_hash);

        verify_xml = verify_xml.replaceFirst(TemplateReplaces.DIGEST_VALUE_SIGNED_DATA_REPLACE, object_data_hash);
      }

      verify_xml = verify_xml.replaceFirst(TemplateReplaces.SIGNATURE_VALUE_REPLACE, so.getSignatureValue());

      // X.509 Certificate replace
      byte[] der = cert.getEncoded();
      byte[] cert_hash = CodingHelper.buildDigest(der);
      String certDigest = CodingHelper.encodeBase64(cert_hash);
      String x509_cert_string = CodingHelper.encodeBase64(der);
      verify_xml = verify_xml.replaceFirst(TemplateReplaces.X509_CERTIFICATE_REPLACE, x509_cert_string);

      // Qualified Properties replaces
      verify_xml = verify_xml.replaceFirst(TemplateReplaces.SIGNING_TIME_REPLACE, so.getDate());
      verify_xml = verify_xml.replaceFirst(TemplateReplaces.DIGEST_VALUE_CERTIFICATE_REPLACE, certDigest);
      verify_xml = verify_xml.replaceFirst(TemplateReplaces.X509_ISSUER_NAME_REPLACE, so.getIssuer());
      verify_xml = verify_xml.replaceFirst(TemplateReplaces.X509_SERIAL_NUMBER_REPLACE, so.getSerialNumber());
      // SigDataRefReplace already done above
      verify_xml = verify_xml.replaceFirst(TemplateReplaces.MIME_TYPE_REPLACE, data.getMimeType());

      // Signed Properties hash
      {
        final String ETSI_SIGNED_PROPERTIES_START_TAG = "<etsi:SignedProperties"; //$NON-NLS-1$
        final String ETSI_SIGNED_PROPERTIES_END_TAG = "</etsi:SignedProperties>"; //$NON-NLS-1$

        final int hash_start = verify_xml.indexOf(ETSI_SIGNED_PROPERTIES_START_TAG);
        assert hash_start >= 0;
        final int hash_end = verify_xml.indexOf(ETSI_SIGNED_PROPERTIES_END_TAG, hash_start) + ETSI_SIGNED_PROPERTIES_END_TAG.length();
        assert hash_end - ETSI_SIGNED_PROPERTIES_END_TAG.length() >= 0;
        assert hash_end > hash_start;

        final String string_to_be_hashed = verify_xml.substring(hash_start, hash_end);
        log.debug("etsi:SignedProperties string to be hashed: " + string_to_be_hashed); //$NON-NLS-1$

        final byte[] bytes_to_be_hashed = string_to_be_hashed.getBytes("UTF-8"); //$NON-NLS-1$
        byte[] sig_prop_code = CodingHelper.buildDigest(bytes_to_be_hashed);
        String sig_prop_hash = CodingHelper.encodeBase64(sig_prop_code);

        verify_xml = verify_xml.replaceFirst(TemplateReplaces.DIGEST_VALUE_SIGNED_PROPERTIES_REPLACE, sig_prop_hash);
      }

      log.debug("prepareXMLContent finished."); //$NON-NLS-1$
      return verify_xml;
    }
    catch (Exception e)
    {
      log.debug(e);
      throw new ConnectorException(310, e);
    }
  }

  protected Properties sendRequest(String url, String mode,
      String request_string) throws ConnectorException
  {
    try
    {
      Properties response_properties = MOASoapConnection.connectMOA(request_string, MOASoapConnection.SERVICE_SIGN, url);
      return response_properties;
    }
    catch (Exception e)
    {
      throw new ConnectorException(330, e);
    }
  }

  /**
   * Holds environment configuration information like templates.
   * 
   * @author wprinz
   */
  public static class Environment
  {
    /**
     * The configuration key of the sign keybox identifier.
     */
    protected static final String SIGN_KEY_IDENTIFIER_KEY = "moa.sign.KeyIdentifier"; //$NON-NLS-1$

    /**
     * The configuration key of the sign request template.
     */
    protected static final String SIGN_REQUEST_TEMPLATE_KEY = "moa.sign.request.detached"; //$NON-NLS-1$

    /**
     * The configuration key of the sign URL.
     */
    protected static final String SIGN_URL_KEY = "moa.sign.url"; //$NON-NLS-1$
    
    /**
     * MOA template file prefix
     */
    protected static final String TEMPLATE_FILE_PREFIX = "./templates/moa.";
    
    /**
     * signing file template sufix
     */
    protected static final String SIGN_TEMPLATE_FILE_SUFIX = ".sign.xml";
    
    /**
     * verifing template file sufix
     */
    protected static final String VERIFY_REQUEST_TEMPLATE_FILE_SUFIX = ".verify.request.xml";    

    /**
     * verifing file template key sufix
     */
    protected static final String VERIFY_TEMPLATE_SUFIX = ".verify.template.xml";

    /**
     * The configuration key of the verify request template.
     */
    protected static final String VERIFY_REQUEST_TEMPLATE_KEY = "moa.verify.request.detached"; //$NON-NLS-1$

    /**
     * The configuration key of the verify template.
     */
    protected static final String VERIFY_TEMPLATE_KEY = "moa.verify.template.detached"; //$NON-NLS-1$

    /**
     * The configuration key of the verify URL.
     */
    protected static final String VERIFY_URL_KEY = "moa.verify.url"; //$NON-NLS-1$

    /**
     * The configuration key of the trust profile id.
     */
    protected static final String VERIFY_TRUST_PROFILE_ID = "moa.verify.TrustProfileID"; //$NON-NLS-1$

    /**
     * The configuration key for the ECDSA cert alg property.
     */
    protected static final String ECDSA_CERT_ALG_KEY = "cert.alg.ecdsa"; //$NON-NLS-1$

    /**
     * The configuration key for the RSA cert alg property.
     */
    protected static final String RSA_CERT_ALG_KEY = "cert.alg.rsa"; //$NON-NLS-1$
    
    protected String profile = null;

    protected String signature_data_url = null;

    protected String sign_key_identifier = null;

    protected String sign_request_template = null;

    protected String sign_url = null;

    protected String verify_request_template = null;

    protected String verify_template = null;

    protected String verify_url = null;

    protected String verify_trust_profile_id = null;

    protected String cert_alg_ecdsa = null;

    protected String cert_alg_rsa = null;

    /**
     * Initializes the environment with a given profile.
     * 
     * @param profile
     *          The configuration profile.
     * @throws SettingsException
     *           f.e.
     * @throws ConnectorException
     *           f.e.
     */
    public Environment(String profile, String signature_data_url) throws ConnectorException
    {
      this.profile = profile;
      
      this.signature_data_url = signature_data_url;

      SettingsReader settings = null;
      try
      {
        settings = SettingsReader.getInstance();
      }
      catch (SettingsException e)
      {
        throw new ConnectorException(300, e);
      }

      this.sign_key_identifier = getConnectorValueFromProfile(settings, profile, SIGN_KEY_IDENTIFIER_KEY);
      
      String sign_request_filename = TEMPLATE_FILE_PREFIX + settings.getValueFromKey("default.moa.algorithm.id") + SIGN_TEMPLATE_FILE_SUFIX;
      
      // try to load template from file
      this.sign_request_template = FileHelper.readFromFile(SettingsReader.relocateFile(sign_request_filename));
      
      if(this.sign_request_template == null)
      {
    	sign_request_filename = getConnectorValueFromProfile(settings, profile, SIGN_REQUEST_TEMPLATE_KEY);
    	this.sign_request_template = FileHelper.readFromFile(SettingsReader.relocateFile(sign_request_filename));
      }
      
      log.debug("\r\n\r\n" + sign_request_filename + "\r\n\r\n");

      //this.sign_request_template = FileHelper.readFromFile(SettingsReader.relocateFile(sign_request_filename));
      if (this.sign_request_template == null)
      {
        // TODO make this a settings exception
        throw new ConnectorException(300, "Can not read the create xml request template"); //$NON-NLS-1$
      }

      this.sign_url = getConnectorValueFromProfile(settings, profile, SIGN_URL_KEY);
      
      String verify_request_filename = TEMPLATE_FILE_PREFIX + settings.getValueFromKey("default.moa.algorithm.id") + VERIFY_REQUEST_TEMPLATE_FILE_SUFIX;
      
      // try to load template file for verifing
      this.verify_request_template = FileHelper.readFromFile(SettingsReader.relocateFile(verify_request_filename));
      
      if(this.verify_request_template == null)
      {
        verify_request_filename = getConnectorValueFromProfile(settings, profile, VERIFY_REQUEST_TEMPLATE_KEY);
        this.verify_request_template = FileHelper.readFromFile(SettingsReader.relocateFile(verify_request_filename));
      }

      if (this.verify_request_template == null)
      {
        // TODO make this a settings exception
        throw new ConnectorException(300, "Can not read the verify xml request template"); //$NON-NLS-1$
      }
      
      // load template key file
      String verify_filename = TEMPLATE_FILE_PREFIX + settings.getValueFromKey("default.moa.algorithm.id") + VERIFY_TEMPLATE_SUFIX;
      this.verify_template = FileHelper.readFromFile(SettingsReader.relocateFile(verify_filename));
      
      if(this.verify_template == null)
      {
    	verify_filename = getConnectorValueFromProfile(settings, profile, VERIFY_TEMPLATE_KEY);
    	this.verify_template = FileHelper.readFromFile(SettingsReader.relocateFile(verify_filename));
      }

      if (this.verify_template == null)
      {
        // TODO make this a settings exception
        throw new ConnectorException(300, "Can not read the verify template"); //$NON-NLS-1$
      }

      this.verify_url = getConnectorValueFromProfile(settings, profile, VERIFY_URL_KEY);

      this.verify_trust_profile_id = settings.getValueFromKey(VERIFY_TRUST_PROFILE_ID);

      this.cert_alg_ecdsa = settings.getValueFromKey(ECDSA_CERT_ALG_KEY);

      this.cert_alg_rsa = settings.getValueFromKey(RSA_CERT_ALG_KEY);

    }

    
    
    public String getProfile()
    {
      return this.profile;
    }

    /**
     * Returns the URL where to load the detached data from.
     * 
     * @return Returns the URL where to load the detached data from.
     */
    public String getSignatureDataUrl()
    {
      return this.signature_data_url;
    }

    /**
     * Returns the sign key identifier.
     * 
     * @return Returns the sign key identifier.
     */
    public String getSignKeyIdentifier()
    {
      return this.sign_key_identifier;
    }

    /**
     * Returns the sign request template.
     * 
     * @return Returns the sign request template.
     */
    public String getSignRequestTemplate()
    {
      return this.sign_request_template;
    }

    /**
     * Returns the sign URL.
     * 
     * @return Returns the sign URL.
     */
    public String getSignURL()
    {
      return this.sign_url;
    }

    /**
     * Returns the verify request template.
     * 
     * @return Returns the verify request template.
     */
    public String getVerifyRequestTemplate()
    {
      return this.verify_request_template;
    }

    /**
     * Returns the verify template.
     * 
     * @return Returns the verify template.
     */
    public String getVerifyTemplate()
    {
      return this.verify_template;
    }

    /**
     * Returns the verify URL.
     * 
     * @return Returns the verify URL.
     */
    public String getVerifyURL()
    {
      return this.verify_url;
    }

    /**
     * Returns the verify trust profile id.
     * 
     * @return Returns the verify trust profile id.
     */
    public String getVerifyTrustProfileId()
    {
      return this.verify_trust_profile_id;
    }

    /**
     * Returns the ecdsa cert alg property.
     * 
     * @return Returns the ecdsa cert alg property.
     */
    public String getCertAlgEcdsa()
    {
      return this.cert_alg_ecdsa;
    }

    /**
     * Returns the rsa cert alg property.
     * 
     * @return Returns the rsa cert alg property.
     */
    public String getCertAlgRsa()
    {
      return this.cert_alg_rsa;
    }

    /**
     * Reads the configuration entry given by the key, first from the given
     * profile, if not found from the defaults.
     * 
     * @param settings
     *          The settings.
     * @param profile
     *          The profile.
     * @param key
     *          The configuration key.
     * @return Returns the configuration entry.
     */
    public static String getConnectorValueFromProfile(SettingsReader settings,
        String profile, String key)
    {
      String value = settings.getValueFromKey("sig_obj." + profile + "." + key); //$NON-NLS-1$//$NON-NLS-2$
      if (value == null)
      {
        value = settings.getValueFromKey(key);
      }
      return value;
    }

  }

}