/**

  * Copyright (c) 2013-2017, 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.github.mock;

 import com.jcabi.aspects.Immutable;

 import com.jcabi.aspects.Loggable;

 import com.jcabi.github.Branch;

 import com.jcabi.github.Branches;

 import com.jcabi.github.Coordinates;

 import com.jcabi.github.Repo;

 import com.jcabi.xml.XML;

 import java.io.IOException;

 import lombok.EqualsAndHashCode;

 import lombok.ToString;

 import org.xembly.Directives;

 /**

  * Mock Git branches.

  *

  * @author Chris Rebert (github@rebertia.com)

  * @version $Id: a21d76ba8a40d7e0facbff7847d506cfce28f9a4 $

  * @since 0.24

  */

 @Immutable

 @Loggable(Loggable.DEBUG)

 @ToString

 @EqualsAndHashCode(of = { "storage", "self", "coords" })

 public final class MkBranches implements Branches {

     /**

      * XPath from a given branch to its commit SHA string.

      */

     private static final String XPATH_TO_SHA = "sha/text()";

     /**

      * Storage.

      */

     private final transient MkStorage storage;

     /**

      * Login of the user logged in.

      */

     private final transient String self;

     /**

      * Repo name.

      */

     private final transient Coordinates coords;

     /**

      * Public ctor.

      * @param stg Storage

      * @param login Username

      * @param rep Repo

      * @throws IOException If there is any I/O problem

      */

     MkBranches(

         final MkStorage stg,

         final String login,

         final Coordinates rep

     ) throws IOException {

         this.storage = stg;

         this.self = login;

         this.coords = rep;

         this.storage.apply(

             new Directives().xpath(

                 String.format(

                     "/github/repos/repo[@coords='%s']",

                     this.coords

                 )

             ).addIf("branches")

         );

     }

     @Override

     public Repo repo() {

         return new MkRepo(this.storage, this.self, this.coords);

     }

     @Override

     public Iterable<Branch> iterate() {

         return new MkIterable<Branch>(

             this.storage,

             String.format("%s/branch", this.xpath()),

             new MkIterable.Mapping<Branch>() {

                 @Override

                 public Branch map(final XML xml) {

                     return new MkBranch(

                         MkBranches.this.storage,

                         MkBranches.this.self,

                         MkBranches.this.coords,

                         xml.xpath("@name").get(0),

                         xml.xpath(MkBranches.XPATH_TO_SHA).get(0)

                     );

                 }

             }

         );

     }

     /**

      * Creates a new branch.

      * @param name Name of branch

      * @param sha Commit SHA

      * @return New branch

      * @throws IOException if there is an I/O problem

      */

     public Branch create(

         final String name,

         final String sha)

         throws IOException {

         final Directives directives = new Directives()

             .xpath(this.xpath())

             .add("branch")

             .attr("name", name)

             .add("sha").set(sha).up();

         this.storage.apply(directives);

         return new MkBranch(this.storage, this.self, this.coords, name, sha);

     }

     /**

      * Gets a branch by name.

      * @param name Name of branch.

      * @return The branch with the given name

      * @throws IOException If there is an I/O problem

      */

     public Branch get(

         final String name

     ) throws IOException {

         return new MkBranch(

             this.storage,

             this.self,

             this.coords,

             name,

             this.storage.xml()

                 .nodes(

                     String.format(

                         "%s/branch[@name='%s']",

                         this.xpath(),

                         name

                     )

                 )

                 .get(0)

                 .xpath(MkBranches.XPATH_TO_SHA)

                 .get(0)

         );

     }

     /**

      * XPath of this element in XML tree.

      * @return XPath

      */

     private String xpath() {

         return String.format(

             "/github/repos/repo[@coords='%s']/branches",

             this.coords

         );

     }

 }