/**

  * 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.dynamo;

 import com.amazonaws.services.dynamodbv2.model.Select;

 import com.google.common.base.Function;

 import com.google.common.collect.Iterables;

 import com.jcabi.aspects.Immutable;

 import com.jcabi.dynamo.Attributes;

 import com.jcabi.dynamo.Item;

 import com.jcabi.dynamo.QueryValve;

 import com.jcabi.dynamo.Region;

 import com.thindeck.api.Deck;

 import com.thindeck.api.Decks;

 import java.io.IOException;

 import java.util.Iterator;

 import lombok.EqualsAndHashCode;

 import lombok.ToString;

 /**

  * Dynamo implementation of {@link com.thindeck.api.Decks}.

  *

  * @author Krzysztof Krason (Krzysztof.Krason@gmail.com)

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

  * @version $Id$

  */

 @ToString

 @Immutable

 @EqualsAndHashCode(of = { "region", "user" })

 final class DyDecks implements Decks {

     /**

      * Region.

      */

     private final transient Region region;

     /**

      * Name of the owner.

      */

     private final transient String user;

     /**

      * Ctor.

      * @param reg Region

      * @param usr URN

      */

     DyDecks(final Region reg, final String usr) {

         this.region = reg;

         this.user = usr;

     }

     @Override

     public Deck get(final String name) throws IOException {

         final Iterator<Item> items = this.region

             .table(DyDeck.TBL)

             .frame()

             .through(new QueryValve().withLimit(1))

             .where(DyDeck.HASH, this.user)

             .where(DyDeck.RANGE, name)

             .iterator();

         if (!items.hasNext()) {

             throw new IOException(

                 String.format("deck '%s' not found", name)

             );

         }

         return new DyDeck(

             this.region, this.user, name

         );

     }

     @Override

     public void add(final String name) throws IOException {

         if (!name.matches("[a-z]{3,12}")) {

             throw new IllegalStateException(

                 String.format(

                     "invalid deck name '%s', must be 3-12 English letters",

                     name

                 )

             );

         }

         final Iterator<Item> items = this.region.table(DyDeck.TBL)

             .frame()

             .through(new QueryValve().withLimit(1))

             .where(DyDeck.HASH, this.user)

             .where(DyDeck.RANGE, name)

             .iterator();

         if (items.hasNext()) {

             throw new IllegalStateException(

                 String.format(

                     "deck '%s' already exists, can't add it again",

                     name

                 )

             );

         }

         this.region.table(DyDeck.TBL).put(

             new Attributes()

                 .with(DyDeck.HASH, this.user)

                 .with(DyDeck.RANGE, name)

                 .with(DyDeck.ATTR_UPDATED, System.currentTimeMillis())

                 .with(

                     DyDeck.ATTR_MEMO,

                     String.format("<deck name='%s/%s'/>", this.user, name)

                 )

         );

     }

     @Override

     public void delete(final String name) {

         final Iterator<Item> items = this.region.table(DyDeck.TBL)

             .frame()

             .through(new QueryValve().withLimit(1))

             .where(DyDeck.HASH, this.user)

             .where(DyDeck.RANGE, name)

             .iterator();

         if (!items.hasNext()) {

             throw new IllegalStateException(

                 String.format(

                     "deck '%s' not found, can't delete",

                     name

                 )

             );

         }

         items.next();

         items.remove();

     }

     @Override

     public Iterable<Deck> iterate() {

         return Iterables.transform(

             this.region.table(DyDeck.TBL)

                 .frame()

                 .through(new QueryValve().withSelect(Select.ALL_ATTRIBUTES))

                 .where(DyDeck.HASH, this.user),

             new Function<Item, Deck>() {

                 @Override

                 public Deck apply(final Item input) {

                     try {

                         return DyDecks.this.get(input.get(DyDeck.RANGE).getS());

                     } catch (final IOException ex) {

                         throw new IllegalStateException(ex);

                     }

                 }

             }

         );

     }

 }