/***********************************************************
Copyright (C) 2015 VeriSign, Inc.

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

http://www.verisign.com/nds/naming/namestore/techdocs.html
 ***********************************************************/

package com.verisign.epp.framework;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.verisign.epp.codec.gen.EPPCodecException;
import com.verisign.epp.codec.gen.EPPFactory;
import com.verisign.epp.codec.gen.EPPMessage;
import com.verisign.epp.codec.nv.EPPNameVerificationCheckCmd;
import com.verisign.epp.codec.nv.EPPNameVerificationCreateCmd;
import com.verisign.epp.codec.nv.EPPNameVerificationInfoCmd;
import com.verisign.epp.codec.nv.EPPNameVerificationMapFactory;
import com.verisign.epp.codec.nv.EPPNameVerificationUpdateCmd;

/**
 * The <code>EPPDomainVerificationCodeHandler</code> class provides an interface
 * for handling Domain Verification Code Commands in a Server implementation.
 * EPPEvents are handled by the handleEvent() method here and routed to the
 * appropriate abstract member function. Subclasses should override the abstract
 * methods to define the desired behavior of a particular command when it is
 * received. A subclassed instance of
 * <code>EPPDomainVerificationCodeHandler</code> should be registered with the
 * <code>EPPDispatcher</code> so that EPPEvents related to the Registry Mapping
 * will be handled there.<br>
 * 
 * @see EPPEventHandler
 * @see EPPEvent
 */
public abstract class EPPNameVerificationHandler implements EPPEventHandler {
  /** Category for logging */
  private static Logger cat = LoggerFactory.getLogger(EPPNameVerificationHandler.class);

  /**
   * Construct an instance of <code>EPPDomainVerificationCodeHandler</code>
   */
  /**
   * Whenever an EPPDomainVerificationCodeHandler instance is created load the
   * corresponding Map Factory into the Codec
   */
  public EPPNameVerificationHandler() {
    try {
      EPPFactory.getInstance().addMapFactory(EPPNameVerificationMapFactory.class.getName());
    }
    catch (EPPCodecException e) {
      cat.error("Couldn't load the Map Factory associated with the Name Verification Mapping", e);
      System.exit(1);
    }
  }

  /**
   * Gets the XML Namespace for the Mapping.
   * 
   * @return <code>EPPDomainVerificationCodeMapFactory.NS</code>
   */
  public String getNamespace() {
    return EPPNameVerificationMapFactory.NS;
  }

  /**
   * This method receives an <code>EPPEvent</code> and routes it to the
   * appropriate abstract method.
   * 
   * @param aEvent
   *           An <code>EPPEvent</code> that contains the
   *           <code>EPPCommand</code>
   * @param aData
   *           Any data that a Server needs to send to this
   *           <code>EPPDomainVerificationCodeHandler</code> instance
   * 
   * @return Response to the event
   * 
   * @exception EPPEventException
   *               Thrown if an unrecognized <code>EPPEvent</code> is received
   */
  public EPPEventResponse handleEvent(EPPEvent aEvent, Object aData) throws EPPEventException {
    try {
      this.preHandleEvent(aEvent, aData);
    }
    catch (EPPHandleEventException e) {
      return new EPPEventResponse(e.getResponse());
    }

    EPPMessage message = aEvent.getMessage();
    EPPEventResponse response = null;

    if (message instanceof EPPNameVerificationCheckCmd) {
      response = doNameVerificationCheck(aEvent, aData);
    }
    else if (message instanceof EPPNameVerificationInfoCmd) {
      response = doNameVerificationInfo(aEvent, aData);
    }
    else if (message instanceof EPPNameVerificationCreateCmd) {
      response = doNameVerificationCreate(aEvent, aData);
    }
    else if (message instanceof EPPNameVerificationUpdateCmd) {
      response = doNameVerificationUpdate(aEvent, aData);
    }

    try {
      this.postHandleEvent(aEvent, aData);
    }
    catch (EPPHandleEventException e) {
      return new EPPEventResponse(e.getResponse());
    }

    return response;
  }

  /**
   * Invoked when the Name Verification Check command is received. Subclasses
   * should define the behavior when a Name Verification Check command is
   * received.
   * 
   * @param aEvent
   *           The <code>EPPEvent</code> that is being handled
   * @param aData
   *           Any data that a Server needs to send to this
   *           <code>EPPNameVerificationHandler</code>
   * 
   * @return EPPEventResponse The response that should be sent back to the
   *         client.
   */
  protected abstract EPPEventResponse doNameVerificationCheck(EPPEvent aEvent, Object aData);

  /**
   * Invoked when the Name Verification Info command is received. Subclasses
   * should define the behavior when a Name Verification Info command is
   * received.
   * 
   * @param aEvent
   *           The <code>EPPEvent</code> that is being handled
   * @param aData
   *           Any data that a Server needs to send to this
   *           <code>EPPNameVerificationHandler</code>
   * 
   * @return EPPEventResponse The response that should be sent back to the
   *         client.
   */
  protected abstract EPPEventResponse doNameVerificationInfo(EPPEvent aEvent, Object aData);

  /**
   * Invoked when an Name Verification Create command is received. Subclasses
   * should define the behavior when Name Verification Create command is
   * received.
   * 
   * @param aEvent
   *           The <code>EPPEvent</code> that is being handled
   * @param aData
   *           Any data that a Server needs to send to this
   *           <code>EPPNameVerificationHandler</code>
   * 
   * @return EPPEventResponse The response that should be sent back to the
   *         client.
   */
  protected abstract EPPEventResponse doNameVerificationCreate(EPPEvent aEvent, Object aData);

  /**
   * Invoked when the Name Verification Update command is received. Subclasses
   * should define the behavior when a Name Verification Update command is
   * received.
   * 
   * @param aEvent
   *           The <code>EPPEvent</code> that is being handled
   * @param aData
   *           Any data that a Server needs to send to this
   *           <code>EPPNameVerificationHandler</code>
   * 
   * @return EPPEventResponse The response that should be sent back to the
   *         client.
   */
  protected abstract EPPEventResponse doNameVerificationUpdate(EPPEvent aEvent, Object aData);

  /**
   * Handles any common behavior that all registry commands need to execute
   * before they execute their command specific behavior. The default
   * implementation does nothing.
   * 
   * @param aEvent
   *           The <code>EPPEvent</code> that is being handled
   * @param aData
   *           Any data that a Server needs to send to this
   *           <code>EPPDomainVerificationCodeHandler</code>
   * 
   * @exception EPPHandleEventException
   *               Thrown if an error condition occurs. It must contain an
   *               <code>EPPEventResponse</code>
   */
  protected void preHandleEvent(EPPEvent aEvent, Object aData) throws EPPHandleEventException {
  }

  /**
   * Handles any common behavior that all registry commands need to execute
   * after they execute their command specific behavior. The default
   * implementation does nothing
   * 
   * @param aEvent
   *           The <code>EPPEvent</code> that is being handled
   * @param aData
   *           Any data that a Server needs to send to this
   *           <code>EPPDomainVerificationCodeHandler</code>
   * 
   * @exception EPPHandleEventException
   *               Thrown if an error condition occurs. It must contain an
   *               <code>EPPEventResponse</code>
   */
  protected void postHandleEvent(EPPEvent aEvent, Object aData) throws EPPHandleEventException {
  }
}
