/**

  * 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.request;

 import com.jcabi.aspects.Immutable;

 import com.jcabi.aspects.Loggable;

 import com.jcabi.http.ImmutableHeader;

 import com.jcabi.http.Request;

 import com.jcabi.http.RequestBody;

 import com.jcabi.http.RequestURI;

 import com.jcabi.http.Response;

 import com.jcabi.http.Wire;

 import com.jcabi.immutable.Array;

 import java.io.ByteArrayOutputStream;

 import java.io.IOException;

 import java.io.InputStream;

 import java.io.OutputStream;

 import java.net.HttpURLConnection;

 import java.net.URI;

 import java.net.URL;

 import java.net.URLConnection;

 import java.util.Collection;

 import java.util.LinkedList;

 import java.util.List;

 import java.util.Map;

 import lombok.EqualsAndHashCode;

 import lombok.ToString;

 /**

  * Implementation of {@link Request}, based on JDK.

  *

  * <p>This implementation will be enough in most situations. However,

  * sometimes you may need better tuning or an ability to fetch custom

  * HTTP methods (JDK doesn't support PATCH, for example). In this case,

  * use {@link ApacheRequest}.

  *

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

  *

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

  * @version $Id: 4f121de7e53e852ab14924e03a5be11cdd718fd5 $

  * @since 0.8

  * @checkstyle ClassDataAbstractionCoupling (500 lines)

  */

 @Immutable

 @EqualsAndHashCode(of = "base")

 @ToString(of = "base")

 @Loggable(Loggable.DEBUG)

 @SuppressWarnings("PMD.TooManyMethods")

 public final class JdkRequest implements Request {

     /**

      * The wire to use.

      * @checkstyle AnonInnerLength (200 lines)

      */

     private static final Wire WIRE = new Wire() {

         // @checkstyle ParameterNumber (6 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 URLConnection raw = new URL(home).openConnection();

             if (!(raw instanceof HttpURLConnection)) {

                 throw new IOException(

                     String.format(

                         "'%s' opens %s instead of expected HttpURLConnection",

                         home, raw.getClass().getName()

                     )

                 );

             }

             final HttpURLConnection conn = HttpURLConnection.class.cast(raw);

             try {

                 conn.setConnectTimeout(connect);

                 conn.setReadTimeout(read);

                 conn.setRequestMethod(method);

                 conn.setUseCaches(false);

                 conn.setInstanceFollowRedirects(false);

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

                     conn.addRequestProperty(header.getKey(), header.getValue());

                 }

                 if (method.equals(Request.POST) || method.equals(Request.PUT)

                     || method.equals(Request.PATCH)) {

                     conn.setDoOutput(true);

                     final OutputStream output = conn.getOutputStream();

                     try {

                         this.writeFully(content, output);

                     } finally {

                         output.close();

                         content.close();

                     }

                 }

                 return new DefaultResponse(

                     req,

                     conn.getResponseCode(),

                     conn.getResponseMessage(),

                     this.headers(conn.getHeaderFields()),

                     this.body(conn)

                 );

             } catch (final IOException exp) {

                 throw new IOException(

                     String.format("Failed %s request to %s", method, home),

                     exp

                 );

             } finally {

                 conn.disconnect();

             }

         }

         /**

          * Fully write the input stream contents to the output stream.

          * @param content The content to write

          * @param output The output stream to write to

          * @throws IOException If an IO Exception occurs

          */

         private void writeFully(final InputStream content,

             final OutputStream output) throws IOException {

             // @checkstyle MagicNumber (1 line)

             final byte[] buffer = new byte[8192];

             for (int bytes = content.read(buffer); bytes != -1;

                 bytes = content.read(buffer)) {

                 output.write(buffer, 0, bytes);

             }

         }

         /**

          * Get headers from response.

          * @param fields ImmutableHeader fields

          * @return Headers

          */

         private Array<Map.Entry<String, String>> headers(

             final Map<String, List<String>> fields) {

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

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

             for (final Map.Entry<String, List<String>> field

                 : fields.entrySet()) {

                 if (field.getKey() == null) {

                     continue;

                 }

                 for (final String value : field.getValue()) {

                     headers.add(new ImmutableHeader(field.getKey(), value));

                 }

             }

             return new Array<>(headers);

         }

         /**

          * Get response body of connection.

          * @param conn Connection

          * @return Body

          * @throws IOException

          */

         private byte[] body(final HttpURLConnection conn) throws IOException {

             final InputStream input;

             if (conn.getResponseCode() >= HttpURLConnection.HTTP_BAD_REQUEST) {

                 input = conn.getErrorStream();

             } else {

                 input = conn.getInputStream();

             }

             final byte[] body;

             if (input == null) {

                 body = new byte[0];

             } else {

                 try {

                     // @checkstyle MagicNumber (1 line)

                     final byte[] buffer = new byte[8192];

                     final ByteArrayOutputStream output =

                         new ByteArrayOutputStream();

                     for (int bytes = input.read(buffer); bytes != -1;

                         bytes = input.read(buffer)) {

                         output.write(buffer, 0, bytes);

                     }

                     body = output.toByteArray();

                 } finally {

                     input.close();

                 }

             }

             return body;

         }

     };

     /**

      * Base request.

      */

     private final transient Request base;

     /**

      * Public ctor.

      * @param url The resource to work with

      */

     public JdkRequest(final URL url) {

         this(url.toString());

     }

     /**

      * Public ctor.

      * @param uri The resource to work with

      */

     public JdkRequest(final URI uri) {

         this(uri.toString());

     }

     /**

      * Public ctor.

      * @param uri The resource to work with

      */

     public JdkRequest(final String uri) {

         this.base = new BaseRequest(JdkRequest.WIRE, uri);

     }

     @Override

     public RequestURI uri() {

         return this.base.uri();

     }

     @Override

     public Request header(final String name, final Object value) {

         return this.base.header(name, value);

     }

     @Override

     public Request reset(final String name) {

         return this.base.reset(name);

     }

     @Override

     public RequestBody body() {

         return this.base.body();

     }

     @Override

     public RequestBody multipartBody() {

         return this.base.multipartBody();

     }

     @Override

     public Request method(final String method) {

         return this.base.method(method);

     }

     @Override

     public Request timeout(final int connect, final int read) {

         return this.base.timeout(connect, read);

     }

     @Override

     public Response fetch() throws IOException {

         return this.base.fetch();

     }

     @Override

     public Response fetch(final InputStream stream) throws IOException {

         return this.base.fetch(stream);

     }

     @Override

     public <T extends Wire> Request through(final Class<T> type,

         final Object... args) {

         return this.base.through(type, args);

     }

 }