package at.gv.egovernment.moa.id.proxy.invoke;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Vector;

import javax.xml.namespace.QName;
import javax.xml.rpc.Call;
import javax.xml.rpc.Service;
import javax.xml.rpc.ServiceFactory;

import org.apache.axis.message.SOAPBodyElement;
import org.w3c.dom.Element;

import at.gv.egovernment.moa.id.AuthenticationException;
import at.gv.egovernment.moa.id.BuildException;
import at.gv.egovernment.moa.id.ParseException;
import at.gv.egovernment.moa.id.ServiceException;
import at.gv.egovernment.moa.id.config.ConfigurationException;
import at.gv.egovernment.moa.id.config.ConnectionParameter;
import at.gv.egovernment.moa.id.config.proxy.ProxyConfigurationProvider;
import at.gv.egovernment.moa.id.data.AuthenticationData;
import at.gv.egovernment.moa.id.data.SAMLStatus;
import at.gv.egovernment.moa.id.proxy.builder.SAMLRequestBuilder;
import at.gv.egovernment.moa.id.proxy.parser.SAMLResponseParser;
import at.gv.egovernment.moa.id.proxy.servlet.ProxyException;
import at.gv.egovernment.moa.id.util.Random;

/**
 * Invoker of 
 * <ul>
 * <li>either the GetAuthenticationData web service of MOA-ID Auth</li>
 * <li>or the API call {@link at.gv.egovernment.moa.id.auth.AuthenticationServer#getAuthenticationData},</li>
 * </ul>
 * depending of the configuration.
 * 
 * @author Paul Ivancsics
 * @version $Id$
 */
public class GetAuthenticationDataInvoker {
  /** Create a new QName object for the webservice endpoint */
  private static final QName SERVICE_QNAME = new QName("GetAuthenticationData");

  /** invoked object for API call of MOA-ID Auth */
  private static Object apiServer = null;
  /** invoked method for API call of MOA-ID Auth */
  private static Method apiMethod = null;
  
  /**
   * Invokes the service passing domain model objects.
   * @param samlArtifact SAML artifact
   * @return AuthenticationData object
   * @throws ServiceException on any exception thrown
   */
  /**
   * Get authentication data from the MOA-ID Auth component,
   * either via API call or via web service call. 
   * @param samlArtifact SAML artifact to be used as a parameter
   * @return AuthenticationData
   */
  public AuthenticationData getAuthenticationData(String samlArtifact) 
    throws ConfigurationException, ProxyException, BuildException, ServiceException, ParseException, AuthenticationException {
    
    ConnectionParameter authConnParam = 
      ProxyConfigurationProvider.getInstance().getAuthComponentConnectionParameter();
    if (authConnParam == null) {
      try {
        if (apiServer == null) {
          Class serverClass = Class.forName("at.gv.egovernment.moa.id.auth.AuthenticationServer");
          Method getInstanceMethod = serverClass.getMethod("getInstance", null);
          apiServer = getInstanceMethod.invoke(null, null);
          apiMethod = serverClass.getMethod(
            "getAuthenticationData", new Class[] {String.class});
        }
        AuthenticationData authData = (AuthenticationData)apiMethod.invoke(apiServer, new Object[] {samlArtifact});
        return authData;
      }
      catch (InvocationTargetException ex) {
        Throwable targetEx = ex.getTargetException();
        if (targetEx instanceof AuthenticationException)
          throw (AuthenticationException) targetEx;
        else
          throw new ProxyException("proxy.09", new Object[] {targetEx.toString()});
      } 
      catch (Throwable ex) {
        throw new ProxyException("proxy.09", new Object[] {ex.toString()});
      } 
    }
    else {
      Element samlpRequest = new SAMLRequestBuilder().build(Random.nextRandom(), samlArtifact);
      Element samlpResponse = getAuthenticationData(samlpRequest);
      SAMLResponseParser srp = new SAMLResponseParser(samlpResponse);
      SAMLStatus status = srp.parseStatusCode();
      if (! "samlp:Success".equals(status.getStatusCode())) {
        // on error status throw exception
        String code = status.getStatusCode();
        if (status.getSubStatusCode() != null && status.getSubStatusCode().length() > 0)
          code += "(" + status.getSubStatusCode() + ")";
        throw new ServiceException("service.02", new Object[] {code, status.getStatusMessage()});
      }
      return srp.parseAuthenticationData();
    }
  }

  /**
   * Invokes the service passing DOM elements.
   * @param request request DOM element
   * @return response DOM element
   * @throws ServiceException on any exception thrown
   */
  public Element getAuthenticationData(Element request) throws ServiceException {
    try {
      Service service = ServiceFactory.newInstance().createService(SERVICE_QNAME);
      Call call = service.createCall();
      SOAPBodyElement body =
        new SOAPBodyElement(request);
      SOAPBodyElement[] params = new SOAPBodyElement[] {body};
      Vector responses;
      SOAPBodyElement response;
      
      String endPoint; 
      ConnectionParameter authConnParam = 
        ProxyConfigurationProvider.getInstance().getAuthComponentConnectionParameter();
      
      //If the ConnectionParameter do NOT exist, we throw an exception ....
      if (authConnParam!=null) {  
        endPoint = authConnParam.getUrl();
        call.setTargetEndpointAddress(endPoint);
        responses = (Vector) call.invoke(SERVICE_QNAME, params);     
        response = (SOAPBodyElement) responses.get(0);
        return response.getAsDOM();
      }
      else
      {
        throw new ServiceException("service.01", null);
      }            
    }
    catch (Exception ex) {
      throw new ServiceException("service.00", new Object[] {ex.toString()}, ex);
    }
  }

}