/**

  * Copyright (c) 2014-2015, Thindeck.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 thindeck.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.thindeck.agents;

 import com.jcabi.aspects.Immutable;

 import com.jcabi.immutable.ArrayMap;

 import com.jcabi.log.Logger;

 import com.jcabi.xml.XML;

 import com.thindeck.api.Agent;

 import java.io.IOException;

 import java.security.SecureRandom;

 import java.util.Collection;

 import java.util.Random;

 import org.apache.commons.lang3.StringUtils;

 import org.xembly.Directive;

 import org.xembly.Directives;

 /**

  * Builds image from repo.

  *

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

  * @version $Id$

  * @since 0.1

  * @checkstyle MultipleStringLiteralsCheck (500 lines)

  */

 @Immutable

 public final class BuildImage implements Agent {

     /**

      * Random.

      */

     private static final Random RND = new SecureRandom();

     /**

      * Script to use.

      */

     private final transient Script script;

     /**

      * Ctor.

      * @throws IOException If fails

      */

     public BuildImage() throws IOException {

         this(

             new Script.Default(

                 BuildImage.class.getResource("build-image.sh")

             )

         );

     }

     /**

      * Ctor.

      * @param spt Script.

      */

     public BuildImage(final Script spt) {

         this.script = spt;

     }

     @Override

     public Iterable<Directive> exec(final XML deck) throws IOException {

         final Collection<XML> repos = deck.nodes(

             "/deck/repo[not(name=/deck/images/image/repo)]"

         );

         final String name = deck.xpath("/deck/@name").get(0);

         final Directives dirs = new Directives().xpath("/deck").addIf("images");

         for (final XML repo : repos) {

             final String rname = repo.xpath("name/text()").get(0);

             Logger.info(

                 this, "There is no Docker image for %s, time to build it",

                 rname

             );

             final String image = this.build(name, repo);

             dirs.xpath("/deck/images").add("image")

                 .add("name").set(image).up()

                 .add("repo").set(rname).up()

                 .add("uri").set(repo.xpath("uri/text() ").get(0)).up()

                 .attr("type", "blue")

                 .xpath("/deck/repo")

                 .remove();

         }

         return dirs;

     }

     /**

      * Build a new image.

      * @param deck Deck name

      * @param repo Repo

      * @return Image name

      * @throws IOException If fails

      */

     private String build(final String deck, final XML repo)

         throws IOException {

         final String name = String.format(

             "%s-%08x", deck,

             BuildImage.RND.nextInt()

         );

         final String hash = "#";

         String uri = repo.xpath("uri/text()").get(0);

         final String branch;

         final String path;

         if (uri.contains(hash)) {

             final String[] tail = StringUtils.substringAfter(uri, hash)

                 .split(":", 2);

             branch = tail[0];

             path = tail[1];

             uri = StringUtils.substringBefore(uri, hash);

         } else {

             branch = "master";

             path = ".";

         }

         final long start = System.currentTimeMillis();

         this.script.exec(

             "t1.thindeck.com",

             new ArrayMap<String, String>()

                 .with("image", name)

                 .with("uri", uri)

                 .with("branch", branch)

                 .with("path", path)

         );

         Logger.info(

             this, "Docker image %s built in %[ms]s",

             name, System.currentTimeMillis() - start

         );

         return name;

     }

 }