/**

  * Copyright (c) 2014-2017, jcabi.com

  * All rights reserved.

  *

  * Redistribution and use in source and binary forms, with or without

  * modification, are permitted provided that the following conditions

  * are met: 1) Redistributions of source code must retain the above

  * copyright notice, this list of conditions and the following

  * disclaimer. 2) Redistributions in binary form must reproduce the above

  * copyright notice, this list of conditions and the following

  * disclaimer in the documentation and/or other materials provided

  * with the distribution. 3) Neither the name of the jcabi.com nor

  * the names of its contributors may be used to endorse or promote

  * products derived from this software without specific prior written

  * permission.

  *

  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT

  * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND

  * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL

  * THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,

  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES

  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR

  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,

  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED

  * OF THE POSSIBILITY OF SUCH DAMAGE.

  */

 package com.jcabi.email.postman;

 import com.jcabi.aspects.Immutable;

 import com.jcabi.aspects.Loggable;

 import com.jcabi.email.Envelope;

 import com.jcabi.email.Postman;

 import com.jcabi.log.Logger;

 import java.io.IOException;

 import java.util.ArrayList;

 import java.util.Arrays;

 import java.util.Collection;

 import javax.mail.Address;

 import javax.mail.Message;

 import javax.mail.MessagingException;

 import lombok.EqualsAndHashCode;

 import lombok.ToString;

 /**

  * Postman that ignores loops (sender equals to recipient).

  *

  * @author Yegor Bugayenko (yegor@teamed.io)

  * @version $Id: 270b070ccacc9a95b535aed55c51666b95681b8f $

  * @since 1.6

  */

 @Immutable

 @ToString

 @EqualsAndHashCode(of = "origin")

 @Loggable(Loggable.DEBUG)

 public final class PostNoLoops implements Postman {

     /**

      * Original postman.

      */

     private final transient Postman origin;

     /**

      * Ctor.

      * @param post Original postman

      */

     public PostNoLoops(final Postman post) {

         this.origin = post;

     }

     @Override

     public void send(final Envelope env) throws IOException {

         final Message msg = env.unwrap();

         try {

             final Address[] rcpts = msg.getAllRecipients();

             final Address[] reply = msg.getReplyTo();

             final Address[] from = msg.getFrom();

             final boolean intersects =

                 this.intersect(rcpts, reply, "Reply-To and Recipients")

                 || this.intersect(rcpts, from, "Recipients and From");

             if (!intersects) {

                 this.origin.send(env);

             }

         } catch (final MessagingException ex) {

             throw new IOException(ex);

         }

     }

     /**

      * Check these two arrays for intersection.

      * @param first Array of addresses

      * @param second Second array

      * @param msg Text for log

      * @return TRUE if they intersect

      */

     private boolean intersect(final Address[] first, final Address[] second,

         final String msg) {

         final Collection<Address> intersection =

             new ArrayList<>(Arrays.asList(first));

         intersection.retainAll(Arrays.asList(second));

         final boolean intersect = !intersection.isEmpty();

         if (intersect) {

             Logger.info(

                 this,

                 "Address(es) %s exist in both %s",

                 intersection, msg

             );

         }

         return intersect;

     }

 }