/**

  * Copyright (c) 2011-2017, 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.http.wire;

 import com.jcabi.aspects.Immutable;

 import com.jcabi.http.ImmutableHeader;

 import com.jcabi.http.Request;

 import com.jcabi.http.Response;

 import com.jcabi.http.Wire;

 import java.io.IOException;

 import java.io.InputStream;

 import java.util.Collection;

 import java.util.LinkedList;

 import java.util.Map;

 import java.util.concurrent.ConcurrentHashMap;

 import java.util.concurrent.ConcurrentMap;

 import javax.ws.rs.core.HttpHeaders;

 import lombok.EqualsAndHashCode;

 import lombok.ToString;

 /**

  * Wire that compresses cookies before sending.

  *

  * <p>This wire compresses all provided {@code Cookie} headers into one

  * and removes empty cookies, for example:

  *

  * <pre> String html = new JdkRequest("http://goggle.com")

  *   .through(CookieOptimizingWire.class)

  *   .header(HttpHeaders.Cookie, "alpha=test")

  *   .header(HttpHeaders.Cookie, "beta=")

  *   .header(HttpHeaders.Cookie, "gamma=foo")

  *   .fetch()

  *   .body();</pre>

  *

  * <p>An actual HTTP request will be sent with just one {@code Cookie}

  * header with a value {@code alpha=test; gamma=foo}.

  *

  * <p>It is highly recommended to use this wire decorator when you're

  * working with cookies.

  *

  * <p>The class is immutable and thread-safe.

  *

  * @author Yegor Bugayenko (yegor@tpc2.com)

  * @version $Id: 7e8b52de61cbad41840939a3eec129912c0d169e $

  * @since 0.10

  * @see <a href="http://tools.ietf.org/html/rfc2965">RFC 2965 "HTTP State Management Mechanism"</a>

  */

 @Immutable

 @ToString(of = "origin")

 @EqualsAndHashCode(of = "origin")

 public final class CookieOptimizingWire implements Wire {

     /**

      * Original wire.

      */

     private final transient Wire origin;

     /**

      * Public ctor.

      * @param wire Original wire

      */

     public CookieOptimizingWire(final Wire wire) {

         this.origin = wire;

     }

     // @checkstyle ParameterNumber (7 lines)

     @Override

     public Response send(final Request req, final String home,

         final String method,

         final Collection<Map.Entry<String, String>> headers,

         final InputStream content,

         final int connect,

         final int read) throws IOException {

         final Collection<Map.Entry<String, String>> hdrs =

             new LinkedList<Map.Entry<String, String>>();

         final ConcurrentMap<String, String> cookies =

             new ConcurrentHashMap<String, String>(0);

         for (final Map.Entry<String, String> header : headers) {

             if (header.getKey().equals(HttpHeaders.COOKIE)) {

                 final String cookie = header.getValue();

                 final int split = cookie.indexOf('=');

                 final String name = cookie.substring(0, split);

                 final String value = cookie.substring(split + 1);

                 if (value.isEmpty()) {

                     cookies.remove(name);

                 } else {

                     cookies.put(name, value);

                 }

             } else {

                 hdrs.add(header);

             }

         }

         if (!cookies.isEmpty()) {

             final StringBuilder text = new StringBuilder(0);

             for (final Map.Entry<String, String> cookie : cookies.entrySet()) {

                 if (cookie.getValue().isEmpty()) {

                     continue;

                 }

                 if (text.length() > 0) {

                     text.append("; ");

                 }

                 text.append(cookie.getKey())

                     .append('=')

                     .append(cookie.getValue());

             }

             hdrs.add(

                 new ImmutableHeader(

                     HttpHeaders.COOKIE,

                     text.toString()

                 )

             );

         }

         return this.origin.send(

             req, home, method, hdrs, content, connect, read

         );

     }

 }