/**

  * 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.response;

 import com.jcabi.aspects.Immutable;

 import com.jcabi.http.Request;

 import com.jcabi.http.Response;

 import com.jcabi.immutable.ArrayMap;

 import com.jcabi.matchers.XhtmlMatchers;

 import com.jcabi.xml.XML;

 import com.jcabi.xml.XMLDocument;

 import com.jcabi.xml.XPathContext;

 import java.net.URI;

 import java.util.Map;

 import javax.xml.namespace.NamespaceContext;

 import lombok.EqualsAndHashCode;

 /**

  * XML response.

  *

  * <p>This response decorator is able to parse HTTP response body as

  * an XML document and manipulate with it afterwords, for example:

  *

  * <pre> String name = new JdkRequest("http://my.example.com")

  *   .header(HttpHeaders.ACCEPT, MediaType.TEXT_XML)

  *   .fetch()

  *   .as(XmlResponse.class)

  *   .assertXPath("/user/name")

  *   .xml()

  *   .xpath("/user/name/text()")

  *   .get(0);</pre>

  *

  * <p>In <a href="http://en.wikipedia.org/wiki/HATEOAS">HATEOAS</a>

  * responses it is convenient to use this decorator's

  * method {@link #rel(String)}

  * in order to follow the link provided in {@code <link>} XML element,

  * for example:

  *

  * <pre> String data = new JdkRequest("http://my.example.com")

  *   .header(HttpHeaders.ACCEPT, MediaType.TEXT_XML)

  *   .fetch()

  *   .as(XmlResponse.class)

  *   .rel("/user/links/link[@rel='next']/@href")

  *   .fetch()

  *   .body();</pre>

  *

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

  *

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

  * @version $Id: 9441436bbd0e41473e29063e0be22884f666a2c3 $

  * @since 0.8

  */

 @Immutable

 @EqualsAndHashCode(callSuper = true)

 public final class XmlResponse extends AbstractResponse {

     /**

      * Map of namespaces.

      */

     private final transient ArrayMap<String, String> namespaces;

     /**

      * Public ctor.

      * @param resp Response

      */

     public XmlResponse(final Response resp) {

         this(resp, new ArrayMap<String, String>());

     }

     /**

      * Public ctor.

      * @param resp Response

      * @param map Map of namespaces

      */

     private XmlResponse(final Response resp,

         final ArrayMap<String, String> map) {

         super(resp);

         this.namespaces = map;

     }

     /**

      * Get XML body.

      * @return XML body

      */

     public XML xml() {

         return new XMLDocument(this.body()).merge(this.context());

     }

     /**

      * Register this new namespace.

      * @param prefix Prefix to use

      * @param uri Namespace URI

      * @return This object

      */

     public XmlResponse registerNs(final String prefix, final String uri) {

         return new XmlResponse(this, this.namespaces.with(prefix, uri));

     }

     /**

      * Verifies HTTP response body XHTML/XML content against XPath query,

      * and throws {@link AssertionError} in case of mismatch.

      * @param xpath Query to use

      * @return This object

      */

     public XmlResponse assertXPath(final String xpath) {

         final String body = this.body();

         if (!XhtmlMatchers.hasXPath(xpath, this.context()).matches(body)) {

             throw new AssertionError(

                 String.format(

                     "XML doesn't contain required XPath '%s':%n%s",

                     xpath, body

                 )

             );

         }

         return this;

     }

     /**

      * Follow XML link.

      * @param query XPath query to fetch new URI

      * @return New request

      */

     public Request rel(final String query) {

         this.assertXPath(query);

         return new RestResponse(this).jump(

             URI.create(this.xml().xpath(query).get(0))

         );

     }

     /**

      * Create XPath context.

      * @return Context

      */

     private NamespaceContext context() {

         XPathContext context = new XPathContext();

         for (final Map.Entry<String, String> entry

             : this.namespaces.entrySet()) {

             context = context.add(entry.getKey(), entry.getValue());

         }

         return context;

     }

 }